Successfully replaced 1 instance(s) of the string in '/tmp/workspace/finals-study-guide/generate_guide.py'

from reportlab.lib.pagesizes import A4
from reportlab.lib import colors
from reportlab.lib.units import cm, mm
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle,
    PageBreak, HRFlowable, KeepTogether
)
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.enums import TA_CENTER, TA_LEFT, TA_RIGHT
from reportlab.pdfgen import canvas
from reportlab.platypus import BaseDocTemplate, Frame, PageTemplate
import textwrap

OUTPUT = '/tmp/workspace/finals-study-guide/FLASHCARD_DECK.pdf'

# ── palette ──────────────────────────────────────────────────────────────────
C_NAVY    = colors.HexColor('#1A3F6F')
C_BLUE    = colors.HexColor('#1E6BB8')
C_SKY     = colors.HexColor('#E8F4FD')
C_GREEN   = colors.HexColor('#1F6B2E')
C_LIME    = colors.HexColor('#EBF8EE')
C_RED     = colors.HexColor('#B30000')
C_ORANGE  = colors.HexColor('#E65C00')
C_YELLOW  = colors.HexColor('#FFF9E6')
C_PINK    = colors.HexColor('#FFF0F0')
C_PURPLE  = colors.HexColor('#4B0082')
C_LAVENDER= colors.HexColor('#F3EEFF')
C_GREY    = colors.HexColor('#F5F5F5')
C_DARK    = colors.HexColor('#222222')
C_MID     = colors.HexColor('#555555')
C_LITE    = colors.HexColor('#EEEEEE')
C_WHITE   = colors.white
C_STAR    = colors.HexColor('#FFD700')
C_TEAL    = colors.HexColor('#00766C')
C_TEAL_LT = colors.HexColor('#E0F5F3')

PAGE_W, PAGE_H = A4  # 595 x 842 pt
MARGIN = 1.5*cm

# ── styles ────────────────────────────────────────────────────────────────────
styles = getSampleStyleSheet()

def S(name, **kw):
    base = kw.pop('parent', 'Normal')
    s = ParagraphStyle(name, parent=styles[base], **kw)
    return s

sTitle  = S('sTitle',  fontSize=28, textColor=C_WHITE, fontName='Helvetica-Bold',
             alignment=TA_CENTER, leading=34, spaceAfter=4)
sSub    = S('sSub',    fontSize=13, textColor=colors.HexColor('#BDD9F2'),
             fontName='Helvetica', alignment=TA_CENTER, leading=16, spaceAfter=0)
sSection= S('sSection',fontSize=15, textColor=C_WHITE, fontName='Helvetica-Bold',
             alignment=TA_CENTER, leading=19)
sTag    = S('sTag',    fontSize=8,  textColor=C_WHITE,  fontName='Helvetica-Bold',
             alignment=TA_CENTER, leading=10, spaceBefore=0, spaceAfter=0)
sTagDark= S('sTagDark',fontSize=8, textColor=C_NAVY,   fontName='Helvetica-Bold',
             alignment=TA_CENTER, leading=10)

sCardQ  = S('sCardQ',  fontSize=12, textColor=C_NAVY, fontName='Helvetica-Bold',
             leading=16, spaceAfter=4)
sCardA  = S('sCardA',  fontSize=12, textColor=C_GREEN, fontName='Helvetica-Bold',
             leading=16, spaceAfter=4)
sCardExp= S('sCardExp',fontSize=9.5,textColor=C_DARK,  fontName='Helvetica',
             leading=13, spaceAfter=0)
sCardWrong= S('sCardWrong', fontSize=9.5, textColor=C_RED, fontName='Helvetica-Oblique',
               leading=13, spaceAfter=0)
sTF_T   = S('sTF_T',   fontSize=11, textColor=C_GREEN, fontName='Helvetica-Bold', leading=15)
sTF_F   = S('sTF_F',   fontSize=11, textColor=C_RED,   fontName='Helvetica-Bold', leading=15)
sSmall  = S('sSmall',  fontSize=8,  textColor=C_MID,   fontName='Helvetica',
             leading=10, alignment=TA_RIGHT)
sNum    = S('sNum',    fontSize=20, textColor=C_WHITE,  fontName='Helvetica-Bold',
             alignment=TA_CENTER, leading=24)
sRepeat = S('sRepeat', fontSize=7.5,textColor=C_STAR,   fontName='Helvetica-Bold',
             alignment=TA_LEFT, leading=9, spaceBefore=0, spaceAfter=0)
sSysSub = S('sSysSub', fontSize=10, textColor=C_BLUE,   fontName='Helvetica-Bold',
             alignment=TA_LEFT, leading=13)

# ── flashcard data ─────────────────────────────────────────────────────────────
# Format: (category_color, tag_label, question, answer, explanation, wrong_answer_note, is_repeated)
# category_color options: 'anatomy','histo','physio','emb'

CARDS = [
    # ══════ ANATOMY ══════
    ('anatomy', '⭐ REPEATED', 'Blood leaving the LEFT VENTRICLE passes through which valve?',
     'Aortic semilunar valve',
     'The LV pumps oxygenated blood into the AORTA via the AORTIC valve. The bicuspid (mitral) valve sits between LA and LV — it does NOT receive blood leaving the LV.',
     'Common wrong answer: Bicuspid valve', True),

    ('anatomy', '⭐ REPEATED', 'The "skeleton" of the heart:',
     'Provides internal support for cardiac chambers (annulus fibrosus)',
     'The fibrous skeleton electrically ISOLATES atria from ventricles and prevents overdilation of valve openings. It is NOT the fibrous pericardium.',
     'Wrong: "fibrous pericardium" or "Purkinje fibers"', True),

    ('anatomy', '⭐ REPEATED', 'Tricuspid valve has 3 cusps. Name them:',
     'Anterior, Septal, Posterior cusps',
     'Right AV valve = tricuspid = 3 cusps. Left AV valve = mitral/bicuspid = 2 cusps (anterior + posterior). Chordae tendineae prevent inversion into atria during systole.',
     '', True),

    ('anatomy', '⭐ REPEATED', 'Cusps of the PULMONARY valve are named:',
     'Left, Right, and Anterior cusps',
     'Pulmonary valve (semilunar) = left, right, anterior. Aortic valve (semilunar) = left, right, posterior (non-coronary). Both have 3 cusps.',
     '', True),

    ('anatomy', 'ANATOMY', 'Epicardium is the same as:',
     'Visceral layer of serous pericardium',
     'Pericardium layers (outside → in): Fibrous → Parietal serous → Pericardial cavity → Visceral serous = EPICARDIUM (covers heart directly). Common exam trap!',
     'Wrong: Parietal pericardium', True),

    ('anatomy', 'ANATOMY', 'AV valves cannot be inverted because of attachment of:',
     'Chordae tendineae (tendinous cords)',
     'Chordae tendineae connect AV valve cusps to papillary muscles, preventing prolapse into the atria during ventricular systole. The fibrous skeleton prevents valve OVERDILATION.',
     'Wrong: interventricular ligament', True),

    ('anatomy', 'ANATOMY', 'Inflammation of the heart\'s pericardium is called:',
     'Pericarditis',
     'Pericarditis: key feature = chest pain RELIEVED by sitting/leaning forward. This distinguishes it from MI. The pericardial friction rub is the classic auscultatory finding.',
     '', True),

    ('anatomy', '⭐ REPEATED', 'Which vein does NOT drain into the coronary sinus?',
     'Anterior cardiac veins',
     'Anterior cardiac veins drain DIRECTLY into the RIGHT ATRIUM — bypassing the coronary sinus. The coronary sinus receives: great, middle, small cardiac veins + oblique vein.',
     'Wrong answer in old version: "Great cardiac vein"', True),

    ('anatomy', '⭐ REPEATED', 'Trachea extends approximately between levels of:',
     'C6 (CVI) to T4 (TIV)',
     'Trachea: starts below cricoid cartilage at C6, bifurcates at T4/T5 (sternal angle = angle of Louis). Tracheal rings = C-shaped HYALINE cartilage (16-20 rings).',
     '', True),

    ('anatomy', '⭐ REPEATED', 'The trachea bifurcates at level:',
     'T4/T5 (TIV/TV) — at the sternal angle (angle of Louis)',
     'The carina is the internal ridge at the bifurcation. In midclavicular line, the inferior lung margin crosses rib VI; in midaxillary line, rib VIII; paravertebral, rib X.',
     'Common wrong: TIV/I or TII', True),

    ('anatomy', '⭐ REPEATED', 'The LEFT main bronchus compared to the RIGHT:',
     'Longer, narrower, and MORE HORIZONTAL',
     'Right bronchus: shorter, wider, more vertical (~25°) → foreign bodies lodge here more often. Left bronchus: longer, narrower, more horizontal (~45°). Left crosses the midline.',
     '', True),

    ('anatomy', '⭐ REPEATED', 'Ciliated pseudostratified columnar epithelium is found in bronchioles — TRUE or FALSE?',
     'FALSE ✗',
     'Ciliated pseudostratified columnar epithelium is found in TRACHEA and larger BRONCHI — NOT bronchioles. Bronchioles have simple columnar/cuboidal + CLARA (Club) cells. No cartilage in bronchioles.',
     'This was answered WRONG in multiple exam versions', True),

    ('anatomy', '⭐ REPEATED', 'The space between visceral and parietal pleura is the _____ cavity:',
     'Pleural cavity',
     'Visceral pleura covers the lung directly. Parietal pleura lines the thoracic wall. The pleural cavity (potential space) contains a small amount of serous fluid. Air entry = PNEUMOTHORAX.',
     '', True),

    ('anatomy', 'ANATOMY', 'The rima glottidis is:',
     'The space between the vocal cords — critical for sound production',
     'The rima glottidis is the opening between the vocal cords. The epiglottis (elastic cartilage) covers the laryngeal inlet during swallowing. Vocal cords covered by NON-KERATINIZED STRATIFIED SQUAMOUS epithelium.',
     '', True),

    ('anatomy', '⭐ REPEATED', 'The largest cartilage of the larynx:',
     'Thyroid cartilage',
     'Thyroid = largest. Forms the "Adam\'s apple." Angle more ACUTE in males (~90°), more OBTUSE in females (~120°). Epiglottis = elastic cartilage. Cricoid = complete ring below thyroid.',
     '', True),

    ('anatomy', '⭐ REPEATED', 'Structure NOT found in the MIDDLE mediastinum:',
     'Thymus (and lungs)',
     'Middle = heart + pericardium, SVC, IVC, ascending aorta, pulmonary trunk/veins, phrenic nerves. THYMUS is in ANTERIOR mediastinum. LUNGS are outside mediastinum entirely.',
     'Wrong: said "aorta" in old version exam', True),

    ('anatomy', '⭐ REPEATED', 'Posterior mediastinal structure closest to the posterior surface of the pericardial sac:',
     'Esophagus',
     'The esophagus lies directly behind the LA/pericardial sac. This is why TEE (transesophageal echo) gives excellent views of the LA. A tumor in the posterior mediastinum → can compress esophagus or descending aorta.',
     '', True),

    ('anatomy', '⭐ REPEATED', 'All structures seen in superior mediastinum EXCEPT:',
     'Right recurrent laryngeal nerve',
     'The RIGHT RLN hooks around the right subclavian artery at the ROOT OF THE NECK — it does NOT descend into the superior mediastinum. The LEFT RLN hooks under the aortic arch IN the superior mediastinum.',
     '', True),

    ('anatomy', 'ANATOMY', 'The thoracic duct lies immediately posterior to (in mid-thorax):',
     'Esophagus',
     'Thoracic duct path: begins at cisterna chyli (L1-L2) → enters thorax at T12 → ascends posterior to esophagus → drains into LEFT subclavian + left IJV junction. Drains ALL lymph except right upper body.',
     '', True),

    ('anatomy', '⭐ REPEATED', 'Left brachiocephalic vein is formed by confluence of:',
     'Left subclavian vein + Left internal jugular vein',
     'Both left and right brachiocephalic veins = subclavian + IJV on each side. The LEFT brachiocephalic crosses the superior mediastinum HORIZONTALLY (longer). The right is short and nearly vertical.',
     'Wrong answer in old version: "right subclavian + right IJV"', True),

    ('anatomy', '⭐ REPEATED', 'Right subclavian artery arises from: (TRUE or FALSE: arises directly from aorta)',
     'FALSE — right subclavian arises from the BRACHIOCEPHALIC TRUNK',
     'Brachiocephalic trunk (from aortic arch) gives: right subclavian + right common carotid. Aortic arch directly gives: brachiocephalic trunk, left CCA, left subclavian (L→R: think "BALD").',
     '', True),

    ('anatomy', '⭐ REPEATED', 'Aortic intima is split from media — what condition is this?',
     'Aortic dissection',
     'Aortic dissection = tear in intima → blood enters aortic wall, splitting intima from media. Stanford A: ascending aorta (surgical emergency). Stanford B: descending (medical management). Risk: Marfan, hypertension.',
     '', True),

    ('anatomy', '⭐ REPEATED', 'Which is NOT a branch of the inferior mesenteric artery (IMA)?',
     'Right colic artery — that is a branch of the SUPERIOR mesenteric artery (SMA)',
     'IMA branches: left colic, sigmoid arteries, superior rectal. SMA branches: ileocolic, right colic, MIDDLE colic, intestinal arteries. IMA = hindgut supply (descending colon → upper anal canal).',
     '', True),

    ('anatomy', '⭐ REPEATED', 'Celiac trunk branches into THREE arteries — which are they?',
     'Left gastric artery, Splenic artery, Common hepatic artery',
     'Remember: "Left Sideshow Comic Hero" or just LEFT GASTRIC + SPLENIC + COMMON HEPATIC. These supply the FOREGUT. IMA is a SEPARATE aortic branch supplying hindgut — it is NOT a celiac branch.',
     'Wrong: "inferior mesenteric artery"', True),

    ('anatomy', '⭐ REPEATED', 'The internal iliac artery branch that supplies the UTERUS:',
     'Uterine artery',
     'Uterine artery from anterior division of internal iliac. It crosses the ureter ("water under the bridge") — key landmark in hysterectomy. The superior gluteal exits ABOVE piriformis; inferior gluteal BELOW.',
     '', True),

    ('anatomy', 'ANATOMY', 'Brachial artery bifurcates into radial and ulnar arteries at:',
     'Level of the ELBOW (apex of cubital fossa) — TRUE',
     'The brachial artery is in the ANTERIOR compartment of the arm (NOT posterior). Its pulse is auscultated for BP measurement. It bifurcates at the cubital fossa into radial (lateral) and ulnar (medial).',
     '', True),

    ('anatomy', 'ANATOMY', 'Basilic vein — deep or superficial?',
     'SUPERFICIAL vein (on MEDIAL side of forearm/arm)',
     'Superficial veins of arm: BASILIC (medial) + CEPHALIC (lateral). They connect at the MEDIAN CUBITAL vein in the cubital fossa (used for venipuncture). Deep veins: brachial, axillary.',
     'This was answered wrong as "deep vein" in multiple exam versions', True),

    ('anatomy', 'ANATOMY', 'Which artery courses through the ANATOMICAL SNUFFBOX?',
     'Radial artery',
     'The anatomical snuffbox is bounded by: abductor pollicis longus, extensor pollicis brevis (anterior), extensor pollicis longus (posterior). Floor = scaphoid + trapezium. Radial pulse felt here.',
     '', True),

    # ══════ HISTOLOGY & EMBRYOLOGY ══════
    ('histo', '⭐ REPEATED', 'The cardiovascular system begins to develop during:',
     'Third week (Week 3) — TRUE',
     'CV system is one of the FIRST organ systems to develop. Heart tube forms at ~day 18-19 from splanchnic mesoderm. The heart begins to beat at ~day 21 (3 weeks). The brain develops later.',
     '', True),

    ('histo', '⭐ REPEATED', 'Primitive heart is partitioned into 4 chambers during the FOURTH week — TRUE or FALSE?',
     'FALSE ✗ — partitioning occurs weeks 5-8 (completed at end of 8th week)',
     'The heart TUBE forms in week 3-4. LOOPING occurs week 4. SEPTATION (creating 4 chambers) occurs weeks 5-8. Do NOT confuse tube formation with chamber septation!',
     'This FALSE statement appeared as TRUE in wrong answer versions', True),

    ('histo', '⭐ REPEATED', 'The two parts of the primitive heart tube that form the OUTFLOW TRACT:',
     'Bulbus cordis + Truncus arteriosus',
     'Primitive heart tube (cranio-caudal): Truncus arteriosus → Bulbus cordis → Primitive ventricle → Primitive atrium → Sinus venosus. Spiral septation of truncus/bulbus → aorta and pulmonary trunk.',
     'Wrong: "Bulbus cordis and primitive ventricles"', True),

    ('histo', '⭐ REPEATED', 'The fetal LEFT ATRIUM is mainly derived from:',
     'Primitive pulmonary vein',
     'The LA is incorporated with the primitive pulmonary vein and its branches during development. The RIGHT ATRIUM is mainly from the right horn of the sinus venosus.',
     '', True),

    ('histo', '⭐ REPEATED', 'Fetal shunt between the aorta and pulmonary artery:',
     'Ductus arteriosus',
     'Ductus arteriosus = connects pulmonary trunk to aortic arch → bypasses lungs (fetal lungs not yet functional). Closes after birth → becomes LIGAMENTUM ARTERIOSUM. Origin = 6th pharyngeal arch artery.',
     'Wrong: "Foramen ovale" (that is the atrial shunt)', True),

    ('histo', '⭐ REPEATED', 'The ductus venosus becomes after it closes:',
     'Ligamentum venosum',
     'Fetal remnants: ductus arteriosus → lig. arteriosum | ductus venosus → lig. venosum | umbilical arteries → medial umbilical ligaments | umbilical vein → lig. teres hepatis (in falciform ligament).',
     'Wrong: "Ligamentum arteriosum"', True),

    ('histo', '⭐ REPEATED', 'The foramen ovale: what is it? What leads to its closure?',
     'Hole between atria. Closes when LEFT atrial pressure EXCEEDS right atrial pressure (at birth)',
     'FO allows oxygenated blood from IVC to bypass right ventricle → go directly to LA. At birth: lungs open → LA pressure rises → FO closes functionally. Probe patent FO exists in ~25% of adults.',
     '', True),

    ('histo', '⭐ REPEATED', 'Changes after birth — umbilical arteries become:',
     'Medial umbilical ligaments',
     'At birth ALL shunts close: (1) DA → lig. arteriosum (2) DV → lig. venosum (3) FO → fossa ovalis (4) Umbilical arteries → medial umbilical ligaments (5) Umbilical vein → lig. teres hepatis.',
     'Wrong: "umbilical vein becomes ligamentum venosum"', True),

    ('histo', '⭐ REPEATED', 'Each statement correctly paired EXCEPT: Right umbilical vein – definitive umbilical vein',
     'INCORRECT pairing — LEFT umbilical vein is definitive (right regresses early)',
     'The RIGHT umbilical vein DEGRESSES during development. Only the LEFT persists as the definitive umbilical vein carrying oxygenated blood from placenta to fetus.',
     '', True),

    ('histo', '⭐ REPEATED', '4th aortic arch develops into (left vs right):',
     'Left 4th = ARCH OF THE AORTA | Right 4th = RIGHT SUBCLAVIAN ARTERY',
     'Pharyngeal arch arteries: 1st → maxillary, 2nd → stapedial/hyoid, 3rd → common carotid+ICA, 4th left → aortic arch, 4th right → right subclavian, 6th left → ductus arteriosus.',
     '', True),

    ('histo', '⭐ REPEATED', 'Internal surface of all CV system components is lined by:',
     'Simple squamous epithelium (endothelium) — TRUE',
     'Endothelium = monolayer of simple squamous cells. Functions: barrier, vasomotor regulation, anti-thrombosis, inflammation control. Found in ALL vessels and heart chambers.',
     '', True),

    ('histo', '⭐ REPEATED', 'Pericytes — TRUE or FALSE: found in wall of ALL blood vessels?',
     'FALSE — pericytes are found only in CAPILLARIES and postcapillary venules',
     'Pericytes are mesenchymal cells that wrap around capillaries/venules. They regulate capillary diameter, support the endothelium, and participate in angiogenesis. Larger vessels have smooth muscle instead.',
     'This was answered TRUE (wrong) in multiple versions', True),

    ('histo', 'HISTO', 'Thickest layer in ARTERIES vs VEINS:',
     'Arteries = Tunica MEDIA (smooth muscle) | Veins = Tunica ADVENTITIA (connective tissue)',
     'Arteries withstand high pressure → thick media with smooth muscle + elastic. Veins carry low-pressure blood → thick adventitia. Capillaries = only intima (endothelium + basement membrane).',
     '', True),

    ('histo', '⭐ REPEATED', 'Lining of lymphatic vessels is composed of:',
     'Simple squamous epithelium (same as blood vessel endothelium)',
     'Lymphatic capillaries are lined by simple squamous endothelium with NO continuous basement membrane. They are more permeable than blood capillaries (have open intercellular junctions). Absent in CNS.',
     'Wrong answers in exam: "stratified squamous" or "simple columnar"', True),

    ('histo', 'HISTO', 'Most immature recognizable cell in the MYELOID series:',
     'Myeloblast',
     'Myeloid series: Myeloblast → Promyelocyte → Myelocyte → Metamyelocyte → Band → Mature granulocyte. Granulocytes have 3 types of granules. Lymphoblast is for lymphoid series.',
     '', True),

    ('histo', '⭐ REPEATED', 'Surfactant — what does it do to surface tension?',
     'DECREASES surface tension — prevents alveolar collapse',
     'Surfactant (DPPC = dipalmitoyl phosphatidylcholine) produced by TYPE II PNEUMOCYTES (septal cells). Reduces surface tension → prevents alveoli from collapsing at end of expiration. Starts forming at ~20-22 wk gestation.',
     'CRITICAL: Surfactant DECREASES (not increases) surface tension', True),

    ('histo', '⭐ REPEATED', 'Cells found in large numbers in terminal bronchioles:',
     'Clara (Club) cells',
     'Club cells (formerly Clara cells): non-ciliated, dome-shaped cells in terminal bronchioles. They produce surfactant components, detoxify inhaled substances, and serve as stem cells for bronchiolar epithelium.',
     '', True),

    ('histo', 'HISTO', 'Connective tissue of the trachea is derived from:',
     'Splanchnic mesenchyme',
     'Tracheal EPITHELIUM = endodermal origin. CARTILAGE and CONNECTIVE TISSUE = splanchnic mesenchyme. The trachea has C-shaped hyaline cartilage rings, incomplete posteriorly (trachealis muscle bridges the gap).',
     '', True),

    ('histo', '⭐ REPEATED', 'Laryngotracheal diverticulum maintains communication with _____ through primordial laryngeal inlet:',
     'Primordial pharynx',
     'The laryngotracheal diverticulum grows from the ventral wall of the pharynx. It communicates with the pharynx through the laryngeal inlet. The tracheoesophageal septum separates it from the esophagus.',
     'Wrong: "pharyngeal cavity and primordial cavity"', True),

    ('histo', 'HISTO', 'Primordial alveoli appear as small bulges on walls of TERMINAL bronchioles — TRUE or FALSE?',
     'FALSE — they appear on walls of RESPIRATORY BRONCHIOLES and alveolar sacs',
     'Terminal bronchioles → respiratory bronchioles → alveolar ducts → alveolar sacs → alveoli. Primordial alveoli appear at the alveolar stage (~36 wks to birth). After birth: ~50 million → 300 million alveoli.',
     '', True),

    ('histo', 'HISTO', 'Olfactory neurons are replaced by basal cells every:',
     '1-2 months',
     'Olfactory epithelium is one of the rare sites of ongoing neurogenesis in adults. Basal (stem) cells replenish olfactory receptor neurons approximately every 1-2 months throughout life.',
     '', False),

    # ══════ PHYSIOLOGY ══════
    ('physio', '⭐ REPEATED', 'Cardiac Output (CO) formula:',
     'CO = Heart Rate × Stroke Volume',
     'Normal CO ≈ 5 L/min (70 bpm × 70 mL). Ejection fraction = SV/EDV × 100% (normal 55-70%). Cardiac index = CO / body surface area. Frank-Starling: ↑EDV → ↑SV → ↑CO.',
     '', True),

    ('physio', '⭐ REPEATED', 'Cardiac conduction system — correct order:',
     'SA node → AV node → Bundle of His → Bundle Branches → Purkinje fibers → Ventricles',
     'SA node = pacemaker (60-100 bpm), right atrium near SVC. AV node: delays impulse 0.1s (allows atrial emptying). Bundle of His → L+R branches → Purkinje fibers (fastest: 1-4 m/s).',
     'Wrong order appeared multiple times in exams', True),

    ('physio', '⭐ REPEATED', 'Acetylcholine causes _____ of the SA node:',
     'Hyperpolarization (slows heart rate)',
     'ACh (parasympathetic/vagal) → M2 receptors → opens IKACh (K+ channels) → hyperpolarization → slower pacemaker rate. Opposite effect: NE/sympathetic → opens Ca²⁺ channels → faster HR.',
     'Wrong: "repolarization" or "depolarization"', True),

    ('physio', '⭐ REPEATED', 'Cardiac weakness is caused by deficiency of _____ in the extracellular fluid:',
     'Calcium (Ca²⁺)',
     'Ca²⁺ is essential for cardiac muscle contraction. Most calcium for cardiac muscle comes from the EXTRACELLULAR space (unlike skeletal muscle which mainly uses SR). Hypocalcemia → reduced contractility → weakness.',
     '', True),

    ('physio', '⭐ REPEATED', 'Active hyperemia occurs when tissue _____ rate increases:',
     'Metabolic rate',
     'Active (functional) hyperemia: ↑metabolism → local vasodilatory metabolites (CO₂, adenosine, K⁺, H⁺, ↓O₂) → vasodilation → ↑blood flow. Examples: exercise-induced, post-meal GI hyperemia.',
     '', True),

    ('physio', '⭐ REPEATED', 'Reactive and active _____ are examples of metabolic control of local blood flow:',
     'Hyperemia',
     'Active hyperemia = ↑flow during activity. Reactive hyperemia = ↑flow AFTER temporary occlusion (repaying oxygen debt). Both are autoregulatory. The most important factor for precapillary sphincter = oxygen level.',
     '', True),

    ('physio', '⭐ REPEATED', 'The _____ are called capacitance vessels or blood reservoirs:',
     'Veins (and venules)',
     'Veins contain ~64% of total blood volume. They are highly compliant (distensible). Arteries = pressure vessels. Capillaries = exchange vessels. Arterioles = resistance vessels (control distribution).',
     '', True),

    ('physio', '⭐ REPEATED', 'Factors that create arterial pressure:',
     'Cardiac output AND Total peripheral resistance',
     'MAP = CO × SVR. BP is controlled by: (1) cardiac output (HR × SV), (2) total peripheral resistance (arterioles), (3) blood volume (kidneys/RAAS). Long-term: kidneys dominate.',
     '', True),

    ('physio', 'PHYSIO', 'According to Poiseuille\'s law, which factor has the GREATEST impact on resistance?',
     'Vessel RADIUS — to the 4th power (R = 8ηL / πr⁴)',
     'Halving vessel radius increases resistance 16-fold (2⁴=16). This is why small changes in arteriole diameter dramatically affect blood flow. Arterioles are the MAJOR site of resistance.',
     '', True),

    ('physio', '⭐ REPEATED', 'Structure that opens and closes the entrance to the capillary:',
     'Precapillary sphincter',
     'Precapillary sphincters regulate entry of blood into individual capillary beds. Most important factor controlling them = tissue O₂ concentration (↓O₂ → sphincters open → more blood flow).',
     '', True),

    ('physio', '⭐ REPEATED', 'During isovolumetric relaxation time (IVRT) — what state are the valves?',
     'ALL valves are CLOSED (mitral AND aortic both closed)',
     'IVRT = from aortic valve closure to mitral valve opening. Ventricular pressure drops rapidly but volume stays constant. Once ventricular pressure < atrial pressure, mitral opens → rapid filling begins.',
     'Wrong: "mitral opens, aortic closed"', True),

    ('physio', '⭐ REPEATED', 'The "a" wave on atrial pressure curve is caused by:',
     'Atrial contraction',
     'JVP/atrial pressure waves: "a" = atrial contraction | "c" = tricuspid bulging | "x" = atrial relaxation | "v" = venous filling during ventricular systole | "y" = tricuspid valve opening.',
     '', True),

    ('physio', '⭐ REPEATED', 'Frank-Starling law — explain:',
     'Increased venous return → more EDV → more stretch → stronger contraction → increased SV',
     'The heart automatically pumps whatever amount of blood it receives. Greater ventricular filling → greater stretch → greater force (up to a limit). This matches cardiac output to venous return without needing neural input.',
     '', True),

    ('physio', '⭐ REPEATED', 'Coronary blood flow mostly occurs during:',
     'DIASTOLE',
     'Left coronary flow is mainly in DIASTOLE because the contracting myocardium compresses left coronary vessels during systole. Right coronary has continuous flow (less wall tension). High HR reduces diastolic time → risk of ischemia.',
     'Wrong: systole', True),

    ('physio', '⭐ REPEATED', 'The afterload for the left ventricle equals:',
     'Aortic pressure (= systemic vascular resistance)',
     'Afterload = resistance against which the ventricle pumps. LV afterload = aortic pressure. RV afterload = pulmonary artery pressure. Increased afterload → ↓SV (unless contractility or preload compensates).',
     '', True),

    ('physio', '⭐ REPEATED', 'Cardiac tamponade — does it increase cardiac output?',
     'FALSE — tamponade DECREASES cardiac output',
     'Pericardial fluid accumulation → compresses heart → impaired filling → ↓CO. Beck\'s triad: (1) hypotension, (2) muffled heart sounds, (3) JVD. Treatment: pericardiocentesis.',
     '', True),

    ('physio', '⭐ REPEATED', 'Collateral flow can damage the myocardium — TRUE or FALSE?',
     'FALSE — collateral flow PROTECTS the myocardium',
     'Collateral vessels provide alternative pathways around blocked coronary arteries. They PROTECT the myocardium from ischemia. The more developed the collaterals, the smaller the infarct.',
     'This wrong answer appeared in 4+ exam versions', True),

    ('physio', 'PHYSIO', 'Pulse pressure: what is it? Where is it highest?',
     'Pulse pressure = Systolic – Diastolic BP. Highest in LARGE ARTERIES',
     'Normal pulse pressure ≈ 40 mmHg (120-80). MAP = DBP + (PP/3) ≈ 93 mmHg. Pulse pressure dampens as blood moves peripherally (capillaries and veins have no pulsatile flow).',
     '', True),

    ('physio', 'PHYSIO', 'What are the normal right atrial pressure values?',
     '~0 mmHg (range: 0-5 mmHg)',
     'Normal pressures: RA ≈ 0 mmHg | RV systolic = 25 mmHg | PA systolic = 25 mmHg | LA = 5-10 mmHg | LV systolic = 120 mmHg | Aorta = 120/80 mmHg.',
     'Wrong answers: 9 mmHg, 20 mmHg', True),

    ('physio', '⭐ REPEATED', 'Edema may be caused by:',
     'All: ↑capillary hydrostatic pressure + ↓oncotic pressure + lymphatic obstruction + ↑capillary permeability',
     'Starling forces: edema when filtration > reabsorption. Causes: (1) heart failure → ↑hydrostatic P, (2) hypoalbuminemia → ↓oncotic P, (3) lymphedema, (4) inflammation → ↑permeability.',
     '', True),

    ('physio', '⭐ REPEATED', 'Lymph capillaries differ from systemic blood capillaries in that they:',
     'Are absent in the CNS (also: no basement membrane, blind-ended, more permeable)',
     'Lymph capillaries are absent in: CNS, bone marrow, cartilage, cornea. They are blind-ended tubes that pick up excess interstitial fluid and return it to circulation.',
     '', True),

    ('physio', 'PHYSIO', 'What does the PR interval on ECG represent?',
     'AV nodal conduction time (onset of atrial depolarization to onset of ventricular depolarization)',
     'Normal PR = 0.12-0.20 sec. Prolonged PR = 1st degree AV block (AV node damage). Short PR = WPW syndrome (accessory pathway bypasses AV node). PR interval prolonged by vagal stimulation.',
     '', True),

    ('physio', 'PHYSIO', 'Vagal stimulation of the SA node — what happens to Ca²⁺ influx?',
     'FALSE — vagal stimulation DECREASES Ca²⁺ influx (and increases K⁺ permeability → slows HR)',
     'Parasympathetic → ACh → M2 receptors → ↑K⁺ permeability → hyperpolarization → slows SA node. Sympathetic → NE → β1 → ↑Ca²⁺/funny channel activity → faster HR.',
     'Wrong: "increases Ca²⁺ influx"', True),

    ('physio', 'PHYSIO', 'Norepinephrine stimulates _____ receptors to affect heart rate:',
     'Beta-1 (β1) adrenergic receptors',
     'β1 in heart: NE/Epi → ↑HR (chronotropy), ↑contractility (inotropy), ↑conduction (dromotropy). β2 in lungs/vessels: bronchodilation, vasodilation. α1 in vessels: vasoconstriction.',
     'Wrong: "alpha-1, alpha-2" or "chemoreceptors"', True),

    ('physio', 'PHYSIO', 'Velocity of blood flow is SLOWEST in:',
     'Capillaries (because they have the LARGEST total cross-sectional area)',
     'Velocity ∝ 1/cross-sectional area. Aorta = smallest CSA → fastest. Capillaries = largest total CSA → slowest. Slow capillary flow = maximum time for gas and nutrient exchange.',
     '', True),

    ('physio', '⭐ REPEATED', 'Peripheral chemoreceptors are located in the carotid SINUS and aortic arch — TRUE or FALSE?',
     'FALSE — they are in the CAROTID BODY (not sinus) and AORTIC BODIES',
     'Peripheral chemoreceptors (O₂ sensors): carotid BODY and aortic BODIES. Carotid SINUS = BARORECEPTOR (senses pressure). Central chemoreceptors = brainstem, sense CO₂/pH (not O₂).',
     '', True),

    ('physio', 'PHYSIO', 'The smaller the alveolus, the _____ the alveolar pressure from surface tension:',
     'GREATER (Law of Laplace: P = 2T/r — smaller radius = greater pressure)',
     'By Laplace\'s law, smaller alveoli would collapse into larger ones without surfactant. Surfactant reduces surface tension MORE in smaller alveoli (it concentrates more), stabilizing alveolar size.',
     '', True),

    ('physio', 'PHYSIO', 'Most CO₂ (~70%) is removed from tissues as:',
     'Bicarbonate ions (HCO₃⁻)',
     'CO₂ transport: 70% as HCO₃⁻ (CO₂ + H₂O → H₂CO₃ → H⁺ + HCO₃⁻, catalyzed by carbonic anhydrase), 23% bound to hemoglobin (carbaminohemoglobin), 7% dissolved in plasma.',
     '', True),

    ('physio', 'PHYSIO', 'How to distinguish pericarditis from MI?',
     'Pericarditis pain is RELIEVED by sitting/leaning FORWARD. MI pain is not.',
     'Pericarditis: sharp, pleuritic pain, worse lying flat, relieved leaning forward. MI: crushing, pressure-like, radiates to L arm/jaw. Pericarditis has friction rub; MI has no friction rub.',
     '', True),

    ('physio', 'PHYSIO', 'Cardiac pain can irradiate to:',
     'Back, left arm (or right arm), jaw',
     'Referred cardiac pain follows dermatomes T1-T4. It can radiate to: left arm (most classic), jaw, neck, back, right arm. This is due to convergence of visceral and somatic afferent fibers in the spinal cord.',
     '', True),
]

# ── colour mapping ────────────────────────────────────────────────────────────
def card_colors(cat):
    if cat == 'anatomy':
        return C_NAVY, C_SKY,    C_BLUE,   'ANATOMY'
    elif cat == 'histo':
        return C_PURPLE, C_LAVENDER, C_PURPLE, 'HISTO / EMBRYO'
    elif cat == 'physio':
        return C_TEAL,  C_TEAL_LT, C_TEAL,  'PHYSIOLOGY'
    else:
        return C_ORANGE, C_YELLOW, C_ORANGE, 'MIXED'

# ── PDF build ─────────────────────────────────────────────────────────────────
def make_pdf(cards, out_path):
    doc = SimpleDocTemplate(
        out_path, pagesize=A4,
        leftMargin=MARGIN, rightMargin=MARGIN,
        topMargin=MARGIN, bottomMargin=MARGIN,
        title='Human Body Finals — Flashcard Deck',
        author='Orris AI'
    )
    story = []

    # ── COVER ────────────────────────────────────────────────────────────────
    cover_bg  = colors.HexColor('#0D2B4E')
    cover_acc = colors.HexColor('#1E6BB8')
    cover_tab = Table(
        [[Paragraph('🃏  HUMAN BODY SYSTEMS', sTitle)],
         [Paragraph('FINALS FLASHCARD DECK', S('cSub', fontSize=18, textColor=colors.HexColor('#90CAF9'),
                    fontName='Helvetica-Bold', alignment=TA_CENTER, leading=22))],
         [Spacer(1, 0.3*cm)],
         [Paragraph('Anatomy  •  Histology & Embryology  •  Physiology', sSub)],
         [Spacer(1, 0.2*cm)],
         [Paragraph(f'{len(cards)} High-Yield Flashcards  •  ⭐ = Repeated on multiple exams', sSub)],
         [Spacer(1, 0.5*cm)],
         [Paragraph('📋  HOW TO USE', S('htuH', fontSize=12, textColor=C_STAR, fontName='Helvetica-Bold', alignment=TA_CENTER, leading=16))],
         [Paragraph('Read the QUESTION, cover the answer, test yourself.\nGreen box = Answer  •  Grey box = Explanation\n⭐ REPEATED cards are highest priority for finals!',
                    S('htuB', fontSize=10, textColor=colors.HexColor('#B0C8E8'), fontName='Helvetica', alignment=TA_CENTER, leading=14))],
        ],
        colWidths=[PAGE_W - 2*MARGIN],
    )
    cover_tab.setStyle(TableStyle([
        ('BACKGROUND', (0,0), (-1,-1), cover_bg),
        ('TOPPADDING',    (0,0), (-1,-1), 8),
        ('BOTTOMPADDING', (0,0), (-1,-1), 8),
        ('LEFTPADDING',   (0,0), (-1,-1), 20),
        ('RIGHTPADDING',  (0,0), (-1,-1), 20),
        ('ROUNDEDCORNERS', (0,0), (-1,-1), [8,8,8,8]),
        ('LINEABOVE', (0,1),(0,1), 1, cover_acc),
        ('LINEABOVE', (0,7),(0,7), 1, cover_acc),
    ]))
    story.append(cover_tab)
    story.append(Spacer(1, 0.4*cm))

    # colour legend
    legend_data = [
        [Paragraph('🟦 ANATOMY', S('la', fontSize=9, textColor=C_NAVY, fontName='Helvetica-Bold', alignment=TA_CENTER)),
         Paragraph('🟪 HISTO / EMBRYO', S('lh', fontSize=9, textColor=C_PURPLE, fontName='Helvetica-Bold', alignment=TA_CENTER)),
         Paragraph('🟩 PHYSIOLOGY', S('lp', fontSize=9, textColor=C_TEAL, fontName='Helvetica-Bold', alignment=TA_CENTER)),
         Paragraph('⭐ = Repeated exam question', S('lr', fontSize=9, textColor=C_ORANGE, fontName='Helvetica-Bold', alignment=TA_CENTER))],
    ]
    leg_tab = Table(legend_data, colWidths=[(PAGE_W-2*MARGIN)/4]*4)
    leg_tab.setStyle(TableStyle([
        ('BACKGROUND', (0,0),(0,0), C_SKY),
        ('BACKGROUND', (1,0),(1,0), C_LAVENDER),
        ('BACKGROUND', (2,0),(2,0), C_TEAL_LT),
        ('BACKGROUND', (3,0),(3,0), C_YELLOW),
        ('BOX', (0,0),(-1,-1), 0.5, C_LITE),
        ('INNERGRID', (0,0),(-1,-1), 0.5, C_LITE),
        ('TOPPADDING', (0,0),(-1,-1), 5),
        ('BOTTOMPADDING', (0,0),(-1,-1), 5),
    ]))
    story.append(leg_tab)
    story.append(PageBreak())

    # ── CARDS ────────────────────────────────────────────────────────────────
    CARDS_PER_PAGE = 3
    card_w = PAGE_W - 2*MARGIN

    for i, (cat, tag, question, answer, explanation, wrong, repeated) in enumerate(cards):
        hdr_c, bg_c, acc_c, cat_label = card_colors(cat)

        # ── card number badge ─────────────────────────────────────────────
        num_cell = Table([[Paragraph(f'{i+1}', sNum)]], colWidths=[1.1*cm], rowHeights=[1.1*cm])
        num_cell.setStyle(TableStyle([
            ('BACKGROUND', (0,0),(-1,-1), hdr_c),
            ('VALIGN', (0,0),(-1,-1), 'MIDDLE'),
            ('TOPPADDING', (0,0),(-1,-1), 0),
            ('BOTTOMPADDING', (0,0),(-1,-1), 0),
            ('ROUNDEDCORNERS', (0,0),(-1,-1), [6,6,0,0]),
        ]))

        # ── category tag ───────────────────────────────────────────────────
        tag_text = f'{tag}' if repeated else cat_label
        tag_style = sTag if tag.startswith('⭐') else S(f'tagS{i}', fontSize=8, textColor=hdr_c,
                    fontName='Helvetica-Bold', alignment=TA_CENTER, leading=10)
        tag_bg = hdr_c if tag.startswith('⭐') else bg_c
        tag_cell = Table([[Paragraph(tag_text, sTag if tag.startswith('⭐') else sTagDark)]],
                          colWidths=[card_w - 1.1*cm - 0.2*cm])
        tag_cell.setStyle(TableStyle([
            ('BACKGROUND', (0,0),(-1,-1), hdr_c if tag.startswith('⭐') else bg_c),
            ('TOPPADDING', (0,0),(-1,-1), 4),
            ('BOTTOMPADDING', (0,0),(-1,-1), 4),
            ('ROUNDEDCORNERS', (0,0),(-1,-1), [0,6,0,0]),
        ]))

        header_row = Table([[num_cell, Spacer(0.2*cm, 1), tag_cell]],
                            colWidths=[1.1*cm, 0.2*cm, card_w - 1.3*cm])
        header_row.setStyle(TableStyle([
            ('VALIGN', (0,0),(-1,-1), 'TOP'),
            ('LEFTPADDING', (0,0),(-1,-1), 0),
            ('RIGHTPADDING', (0,0),(-1,-1), 0),
            ('TOPPADDING', (0,0),(-1,-1), 0),
            ('BOTTOMPADDING', (0,0),(-1,-1), 0),
        ]))

        # ── question ──────────────────────────────────────────────────────
        q_para = Paragraph(f'<b>Q:</b>  {question}', sCardQ)
        q_cell = Table([[q_para]], colWidths=[card_w])
        q_cell.setStyle(TableStyle([
            ('BACKGROUND', (0,0),(-1,-1), C_WHITE),
            ('TOPPADDING', (0,0),(-1,-1), 8),
            ('BOTTOMPADDING', (0,0),(-1,-1), 8),
            ('LEFTPADDING', (0,0),(-1,-1), 10),
            ('RIGHTPADDING', (0,0),(-1,-1), 10),
            ('LINEBELOW', (0,0),(-1,-1), 1.5, acc_c),
        ]))

        # ── answer ────────────────────────────────────────────────────────
        a_para = Paragraph(f'<b>✔  {answer}</b>', sCardA)
        a_rows = [[a_para]]
        if wrong:
            a_rows.append([Paragraph(f'✗  {wrong}', sCardWrong)])
        if explanation:
            a_rows.append([Spacer(1, 2)])
            a_rows.append([Paragraph(explanation, sCardExp)])

        a_cell = Table(a_rows, colWidths=[card_w])
        a_cell.setStyle(TableStyle([
            ('BACKGROUND', (0,0),(-1,-1), C_LIME if cat != 'physio' else C_TEAL_LT),
            ('TOPPADDING', (0,0),(-1,-1), 7),
            ('BOTTOMPADDING', (0,0),(-1,-1), 7),
            ('LEFTPADDING', (0,0),(-1,-1), 10),
            ('RIGHTPADDING', (0,0),(-1,-1), 10),
        ]))

        # ── assemble card ─────────────────────────────────────────────────
        card = Table(
            [[header_row], [q_cell], [a_cell]],
            colWidths=[card_w],
        )
        card.setStyle(TableStyle([
            ('BOX', (0,0),(-1,-1), 1.5, acc_c),
            ('TOPPADDING', (0,0),(-1,-1), 0),
            ('BOTTOMPADDING', (0,0),(-1,-1), 0),
            ('LEFTPADDING', (0,0),(-1,-1), 0),
            ('RIGHTPADDING', (0,0),(-1,-1), 0),
            ('ROUNDEDCORNERS', (0,0),(-1,-1), [8,8,8,8]),
        ]))

        story.append(KeepTogether([card]))
        story.append(Spacer(1, 0.55*cm))

    # ── BACK COVER ────────────────────────────────────────────────────────────
    story.append(PageBreak())
    back = Table(
        [[Paragraph('🏁  STUDY TIPS FOR FINALS', S('bT', fontSize=16, textColor=C_WHITE,
                    fontName='Helvetica-Bold', alignment=TA_CENTER, leading=20))],
         [Paragraph('''
<b>⭐ Highest priority cards:</b> Any card with ⭐ REPEATED appeared in 3–4 exam versions. Master these first.<br/><br/>
<b>🔑 Common traps to avoid:</b><br/>
• Surfactant <b>DECREASES</b> (NOT increases) surface tension<br/>
• Heart chambers partition in weeks <b>5–8</b> (NOT week 4)<br/>
• Anterior cardiac veins drain into <b>right atrium</b> (NOT coronary sinus)<br/>
• Basilic vein is <b>superficial</b> (NOT deep)<br/>
• Right subclavian arises from <b>brachiocephalic trunk</b> (NOT aorta directly)<br/>
• Pericytes are only in <b>capillaries/venules</b> (NOT all vessels)<br/>
• Collateral flow <b>PROTECTS</b> the myocardium (does NOT damage it)<br/>
• Left bronchus: <b>longer, narrower, more horizontal</b> (right = wider, more vertical)<br/>
• Ciliated pseudostratified epithelium in bronchioles = <b>FALSE</b><br/>
• Peripheral chemoreceptors = carotid <b>BODY</b> (not sinus — sinus is a baroreceptor!)<br/>
• Cardiac tamponade <b>DECREASES</b> cardiac output (not increases)<br/>
• IMA branches: left colic, sigmoid, superior rectal — <b>NOT</b> right colic (that's SMA)<br/><br/>
<b>🩺 Murmurs quick ref:</b><br/>
Mitral: <b>apex, 5th ICS, midclavicular</b> | Aortic: <b>2nd ICS right sternal border</b><br/>
Pericarditis pain: relieved by <b>sitting/leaning forward</b><br/><br/>
<b>📐 Numbers to remember:</b><br/>
Normal BP = <b>120/80</b> | Right atrial pressure = <b>~0 mmHg</b> | RV systolic = <b>25 mmHg</b><br/>
Trachea = C6–T4 | Bifurcation = T4/T5 | Thoracic duct from = T12/L2<br/>
Lung lobes: Right = <b>3</b>, Left = <b>2</b>
         ''', S('bB', fontSize=9.5, textColor=colors.HexColor('#D0E8FF'),
                fontName='Helvetica', alignment=TA_LEFT, leading=14, spaceBefore=0, spaceAfter=0))],
        ],
        colWidths=[PAGE_W - 2*MARGIN],
    )
    back.setStyle(TableStyle([
        ('BACKGROUND', (0,0),(-1,-1), colors.HexColor('#0D2B4E')),
        ('TOPPADDING', (0,0),(-1,-1), 12),
        ('BOTTOMPADDING', (0,0),(-1,-1), 12),
        ('LEFTPADDING', (0,0),(-1,-1), 20),
        ('RIGHTPADDING', (0,0),(-1,-1), 20),
        ('LINEBELOW', (0,0),(0,0), 1, colors.HexColor('#1E6BB8')),
        ('ROUNDEDCORNERS', (0,0),(-1,-1), [8,8,8,8]),
    ]))
    story.append(back)

    doc.build(story)
    print(f'Done: {out_path}')

make_pdf(CARDS, OUTPUT)

import random
from reportlab.lib.pagesizes import A4
from reportlab.lib import colors
from reportlab.lib.units import cm, mm
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle,
    PageBreak, KeepTogether, HRFlowable
)
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.enums import TA_CENTER, TA_LEFT, TA_RIGHT, TA_JUSTIFY

OUTPUT_EXAM = '/tmp/workspace/finals-study-guide/PRACTICE_EXAM.pdf'
PAGE_W, PAGE_H = A4
MARGIN = 1.8*cm
random.seed(42)   # reproducible shuffle

# ── palette ──────────────────────────────────────────────────────────────────
C_NAVY   = colors.HexColor('#1A3F6F')
C_BLUE   = colors.HexColor('#1E6BB8')
C_SKY    = colors.HexColor('#DFF0FF')
C_GREEN  = colors.HexColor('#1F6B2E')
C_LIME   = colors.HexColor('#EBF8EE')
C_RED    = colors.HexColor('#B30000')
C_PINK   = colors.HexColor('#FFF0F0')
C_ORANGE = colors.HexColor('#C05000')
C_YELLOW = colors.HexColor('#FFF8DC')
C_PURPLE = colors.HexColor('#4A007A')
C_LAV    = colors.HexColor('#F3EEFF')
C_TEAL   = colors.HexColor('#005F58')
C_TEAL_L = colors.HexColor('#E0F5F3')
C_GREY   = colors.HexColor('#F5F5F5')
C_DARK   = colors.HexColor('#1A1A1A')
C_MID    = colors.HexColor('#555555')
C_LITE   = colors.HexColor('#DDDDDD')
C_WHITE  = colors.white
C_GOLD   = colors.HexColor('#B8860B')

def S(name, **kw):
    s = ParagraphStyle(name, parent=getSampleStyleSheet()['Normal'], **kw)
    return s

# subject tag colours
SUBJ_COLORS = {
    'A': (C_NAVY,   C_SKY,   'ANATOMY'),
    'H': (C_PURPLE, C_LAV,   'HISTO/EMB'),
    'P': (C_TEAL,   C_TEAL_L,'PHYSIOLOGY'),
}

# ── QUESTION BANK ─────────────────────────────────────────────────────────────
# Each entry:
# (subject, qtype, stem, options_list, correct_letter, explanation, is_repeated)
# qtype = 'mcq' | 'tf' | 'fill'  (fill = short answer; rendered as MCQ with 4 plausible choices)
# For tf: options = ['True','False'], correct = 'A' or 'B'

QUESTIONS = [
    # ══════════ ANATOMY ══════════
    ('A','mcq',
     'Blood leaving the LEFT VENTRICLE passes through which valve?',
     ['A) Bicuspid (mitral) valve',
      'B) Tricuspid valve',
      'C) Aortic semilunar valve',
      'D) Pulmonary semilunar valve'],
     'C',
     'The LV ejects oxygenated blood into the AORTA via the AORTIC SEMILUNAR valve. The mitral valve sits BETWEEN LA and LV — it does not receive outflow from the LV.',
     True),

    ('A','mcq',
     'Which vein does NOT drain into the coronary sinus?',
     ['A) Great cardiac vein',
      'B) Middle cardiac vein',
      'C) Anterior cardiac veins',
      'D) Small cardiac vein'],
     'C',
     'Anterior cardiac veins drain DIRECTLY into the right atrium, bypassing the coronary sinus. All other major cardiac veins (great, middle, small, oblique, posterior) drain into the coronary sinus.',
     True),

    ('A','mcq',
     'The tricuspid valve has 3 cusps named:',
     ['A) Superior, inferior, and medial',
      'B) Anterior, posterior, and lateral',
      'C) Anterior, septal, and posterior',
      'D) Medial, lateral, and posterior'],
     'C',
     'RIGHT AV valve (tricuspid) = anterior, septal, posterior cusps. LEFT AV valve (mitral) = 2 cusps: anterior + posterior. The pulmonary semilunar valve cusps = left, right, anterior.',
     True),

    ('A','tf',
     'The epicardium is the same as the visceral layer of serous pericardium.',
     ['A) True', 'B) False'],
     'A',
     'Epicardium = visceral pericardium. It directly covers the heart. Layers outside → in: fibrous pericardium → parietal serous → pericardial cavity → visceral serous (= epicardium).',
     True),

    ('A','mcq',
     'The atrioventricular valves cannot be inverted during ventricular systole because of the attachment of:',
     ['A) Interventricular septum',
      'B) Chordae tendineae',
      'C) Cardiac fibrous skeleton',
      'D) Pectinate muscles'],
     'B',
     'Chordae tendineae connect AV valve cusps to papillary muscles, preventing inversion (prolapse) into the atria during systole. The fibrous skeleton prevents OVERDILATION of valve openings — a separate function.',
     True),

    ('A','mcq',
     'Which structure is NOT found in the middle mediastinum?',
     ['A) Heart and pericardium',
      'B) Ascending aorta',
      'C) Thymus',
      'D) Phrenic nerves'],
     'C',
     'The THYMUS is in the ANTERIOR mediastinum (major structure in children). The middle mediastinum contains: heart + pericardium, ascending aorta, SVC, IVC, pulmonary trunk/veins, phrenic nerves.',
     True),

    ('A','mcq',
     'The trachea bifurcates at which vertebral level?',
     ['A) C6',
      'B) T1/T2',
      'C) T4/T5 (sternal angle)',
      'D) T8'],
     'C',
     'Trachea bifurcates at T4/T5 = sternal angle (angle of Louis). The carina is the internal ridge at this point. Trachea starts at C6 (below cricoid cartilage). Range = C6 to T4.',
     True),

    ('A','mcq',
     'Compared to the RIGHT main bronchus, the LEFT main bronchus is:',
     ['A) Shorter, wider, and more vertical',
      'B) Shorter, narrower, and more horizontal',
      'C) Longer, narrower, and more horizontal',
      'D) Longer, wider, and more vertical'],
     'C',
     'Left bronchus: longer, narrower, ~45° angle (horizontal). Right: shorter, wider, ~25° angle (vertical). Because right is wider + more vertical → inhaled foreign bodies lodge in right bronchus more commonly.',
     True),

    ('A','tf',
     'Ciliated pseudostratified columnar epithelium is found in bronchioles.',
     ['A) True', 'B) False'],
     'B',
     'Ciliated pseudostratified columnar epithelium = trachea and larger BRONCHI, NOT bronchioles. Bronchioles have simple columnar/cuboidal with CLARA (Club) cells. No cartilage in bronchioles either.',
     True),

    ('A','mcq',
     'The space between the visceral and parietal pleura is known as the:',
     ['A) Pericardial cavity',
      'B) Peritoneal cavity',
      'C) Mediastinum',
      'D) Pleural cavity'],
     'D',
     'The pleural cavity is the potential space between visceral (covers lung) and parietal (lines thoracic wall) pleura. Contains a small amount of serous fluid. Air entry = PNEUMOTHORAX.',
     True),

    ('A','mcq',
     'The largest cartilage of the larynx is the:',
     ['A) Cricoid cartilage',
      'B) Thyroid cartilage',
      'C) Epiglottis',
      'D) Arytenoid cartilage'],
     'B',
     'Thyroid cartilage is the LARGEST laryngeal cartilage (forms the "Adam\'s apple"). Cricoid = only complete ring, directly below thyroid. Epiglottis = elastic cartilage. Arytenoids = paired, have vocal + muscular processes.',
     True),

    ('A','mcq',
     'Which type of tissue makes up the epiglottis?',
     ['A) Hyaline cartilage',
      'B) Fibrocartilage',
      'C) Elastic cartilage',
      'D) Dense fibrous connective tissue'],
     'C',
     'Epiglottis = ELASTIC cartilage (flexible, springs back). The thyroid, cricoid, and most of arytenoid cartilages = HYALINE cartilage. The corniculate and cuneiform cartilages are also elastic.',
     True),

    ('A','mcq',
     'The left brachiocephalic vein is formed by the confluence of which two veins?',
     ['A) Left subclavian + Left internal jugular',
      'B) Right subclavian + Right internal jugular',
      'C) Left subclavian + Left external jugular',
      'D) Left common carotid + Left subclavian'],
     'A',
     'Both brachiocephalic veins = subclavian + IJV on each side. The LEFT brachiocephalic crosses the superior mediastinum HORIZONTALLY to join the right brachiocephalic → forming the SVC.',
     True),

    ('A','tf',
     'The right subclavian artery arises directly from the aortic arch.',
     ['A) True', 'B) False'],
     'B',
     'The RIGHT subclavian arises from the BRACHIOCEPHALIC TRUNK (which arises from the aortic arch). The LEFT subclavian artery arises DIRECTLY from the aortic arch. The brachiocephalic trunk gives: right subclavian + right CCA.',
     True),

    ('A','mcq',
     'The azygos vein terminates by draining into the:',
     ['A) Inferior vena cava',
      'B) Right brachiocephalic vein',
      'C) Superior vena cava',
      'D) Pulmonary veins'],
     'C',
     'The azygos vein ascends on the RIGHT side of the vertebral column, arches over the right main bronchus at T4, and drains into the SVC. It drains the thoracic wall. The hemiazygos drains the left lower thoracic wall.',
     True),

    ('A','mcq',
     'Splitting of the aortic intima from the media is called:',
     ['A) Aortic aneurysm',
      'B) Aortic dissection',
      'C) Aortic stenosis',
      'D) Aortic coarctation'],
     'B',
     'Aortic dissection = intimal tear → blood enters the aortic wall, creating a false lumen. Stanford A: ascending aorta (surgical emergency). Stanford B: descending aorta (medical management). Risk: Marfan syndrome, hypertension.',
     True),

    ('A','mcq',
     'Which of the following is NOT a branch of the inferior mesenteric artery?',
     ['A) Left colic artery',
      'B) Sigmoid arteries',
      'C) Right colic artery',
      'D) Superior rectal artery'],
     'C',
     'IMA branches: left colic, sigmoid arteries, superior rectal. RIGHT COLIC is a branch of the SUPERIOR MESENTERIC ARTERY (SMA). IMA supplies hindgut derivatives: descending colon, sigmoid, rectum, upper anal canal.',
     True),

    ('A','mcq',
     'The celiac trunk divides into three major branches. Which of the following is one of them?',
     ['A) Inferior mesenteric artery',
      'B) Superior mesenteric artery',
      'C) Splenic artery',
      'D) Renal artery'],
     'C',
     'Celiac trunk (T12) = left gastric + splenic + common hepatic arteries. Supplies FOREGUT. IMA (L3) and SMA (L1) are SEPARATE branches of the abdominal aorta — NOT branches of the celiac trunk.',
     True),

    ('A','mcq',
     'The internal iliac artery branch that supplies the uterus is the:',
     ['A) Ovarian artery',
      'B) Obturator artery',
      'C) Uterine artery',
      'D) Vaginal artery'],
     'C',
     'Uterine artery = branch of the anterior division of the internal iliac. It crosses the ureter ("water under the bridge") — key landmark in hysterectomy to avoid ureteric injury.',
     True),

    ('A','mcq',
     'At the apex of the cubital fossa, the brachial artery divides into:',
     ['A) Radial and median arteries',
      'B) Ulnar and axillary arteries',
      'C) Radial and ulnar arteries',
      'D) Anterior and posterior interosseous arteries'],
     'C',
     'The brachial artery (in the ANTERIOR compartment of the arm) bifurcates at the apex of the cubital fossa into the RADIAL (lateral) and ULNAR (medial) arteries. Its pulse is used for blood pressure measurement.',
     True),

    ('A','tf',
     'The basilic vein is considered a deep vein of the upper limb.',
     ['A) True', 'B) False'],
     'B',
     'The basilic vein is a SUPERFICIAL vein on the MEDIAL side of the arm/forearm. The cephalic vein is superficial on the LATERAL side. Deep veins of the arm = brachial, axillary veins.',
     True),

    ('A','mcq',
     'Which artery passes through the anatomical snuffbox?',
     ['A) Ulnar artery',
      'B) Brachial artery',
      'C) Radial artery',
      'D) Anterior interosseous artery'],
     'C',
     'The radial artery crosses the floor of the anatomical snuffbox (floor = scaphoid + trapezium). The radial pulse can be palpated here. The Allen test checks patency of radial and ulnar arteries.',
     True),

    ('A','mcq',
     'In a fracture of the midshaft of the humerus, which artery is most likely injured?',
     ['A) Axillary artery',
      'B) Anterior circumflex humeral artery',
      'C) Profunda brachii artery',
      'D) Ulnar artery'],
     'C',
     'The profunda brachii (deep brachial artery) and the RADIAL NERVE travel together in the radial groove (spiral groove) of the humerus. Midshaft fracture → radial nerve palsy + profunda brachii injury.',
     True),

    ('A','mcq',
     'In the posterior mediastinum, which structure is most closely applied to the posterior surface of the pericardial sac?',
     ['A) Descending thoracic aorta',
      'B) Thoracic duct',
      'C) Esophagus',
      'D) Azygos vein'],
     'C',
     'The esophagus lies directly posterior to the left atrium/pericardial sac. This anatomical relationship is why transesophageal echocardiography (TEE) provides excellent views of the left atrium.',
     True),

    ('A','mcq',
     'All structures are seen in the superior mediastinum EXCEPT:',
     ['A) Left recurrent laryngeal nerve',
      'B) Trachea',
      'C) Right recurrent laryngeal nerve',
      'D) Esophagus'],
     'C',
     'The RIGHT RLN hooks around the right subclavian artery at the ROOT OF THE NECK — it does NOT descend into the superior mediastinum. The LEFT RLN hooks under the aortic arch inside the superior mediastinum.',
     True),

    # ══════════ HISTOLOGY / EMBRYOLOGY ══════════
    ('H','mcq',
     'The cardiovascular system begins to develop during:',
     ['A) First week',
      'B) Third week',
      'C) Fifth week',
      'D) Eighth week'],
     'B',
     'The CV system is one of the FIRST organ systems to develop. The heart tube forms at ~day 18-19. The heart begins to beat at day ~21 (week 3). Septation into 4 chambers occurs weeks 5-8.',
     True),

    ('H','tf',
     'The primitive heart is partitioned into four separate chambers during the fourth week of development.',
     ['A) True', 'B) False'],
     'B',
     'The heart TUBE forms in weeks 3-4 and undergoes LOOPING in week 4. SEPTATION (creating 4 chambers) occurs weeks 5-8, completed at the end of the 8th week. Do NOT confuse tube formation with chamber septation.',
     True),

    ('H','mcq',
     'Which two parts of the primitive heart tube form the OUTFLOW TRACT?',
     ['A) Sinus venosus and primitive atrium',
      'B) Primitive ventricle and sinus venosus',
      'C) Bulbus cordis and truncus arteriosus',
      'D) Primitive atrium and bulbus cordis'],
     'C',
     'Primitive heart tube (cranio-caudal): TRUNCUS ARTERIOSUS → BULBUS CORDIS → Primitive ventricle → Primitive atrium → Sinus venosus. Spiral septation of the truncus/bulbus creates the aorta and pulmonary trunk.',
     True),

    ('H','mcq',
     'The fetal left atrium is mainly derived from the:',
     ['A) Sinus venosus',
      'B) Primitive pulmonary vein',
      'C) Common cardinal vein',
      'D) Bulbus cordis'],
     'B',
     'The LA is mainly formed by incorporation of the PRIMITIVE PULMONARY VEIN and its branches into the posterior atrial wall. The RIGHT ATRIUM derives mainly from the right horn of the sinus venosus.',
     True),

    ('H','mcq',
     'The fetal shunt between the pulmonary trunk and aorta is the:',
     ['A) Foramen ovale',
      'B) Ductus venosus',
      'C) Ductus arteriosus',
      'D) Umbilical vein'],
     'C',
     'Ductus arteriosus connects pulmonary trunk to aortic arch → bypasses fetal (non-functional) lungs. After birth, it closes and becomes the LIGAMENTUM ARTERIOSUM. Embryonic origin = 6th pharyngeal arch artery.',
     True),

    ('H','mcq',
     'After birth, the ductus venosus becomes the:',
     ['A) Ligamentum arteriosum',
      'B) Medial umbilical ligament',
      'C) Ligamentum teres hepatis',
      'D) Ligamentum venosum'],
     'D',
     'Fetal structure → adult remnant: ductus arteriosus → ligamentum ARTERIOSUM | ductus venosus → ligamentum VENOSUM | umbilical arteries → medial umbilical ligaments | umbilical vein → lig. TERES HEPATIS.',
     True),

    ('H','mcq',
     'The foramen ovale closes after birth because:',
     ['A) The ductus arteriosus closes first',
      'B) Left atrial pressure exceeds right atrial pressure',
      'C) The lungs deflate and reduce pulmonary pressure',
      'D) Aldosterone causes fluid retention'],
     'B',
     'At birth: lungs expand → pulmonary resistance drops → LA pressure rises above RA pressure → pushes septum primum against septum secundum → FO closes functionally. Anatomical closure may take weeks to months.',
     True),

    ('H','mcq',
     'Each of the following statements is correctly paired EXCEPT:',
     ['A) Ductus arteriosus → ligamentum arteriosum',
      'B) Right umbilical vein → definitive umbilical vein',
      'C) Umbilical arteries → medial umbilical ligaments',
      'D) Ductus venosus → ligamentum venosum'],
     'B',
     'The RIGHT umbilical vein REGRESSES early in development. The LEFT umbilical vein persists as the definitive umbilical vein. After birth: left umbilical vein → ligamentum teres hepatis (in the falciform ligament).',
     True),

    ('H','mcq',
     'The left 4th aortic arch artery develops into the:',
     ['A) Right subclavian artery',
      'B) Common carotid artery',
      'C) Ductus arteriosus',
      'D) Arch of the aorta'],
     'D',
     '4th arch LEFT → ARCH OF THE AORTA. 4th arch RIGHT → right subclavian artery. 6th arch LEFT → ductus arteriosus. 3rd arch → common carotid + ICA. 1st arch → maxillary artery.',
     True),

    ('H','tf',
     'The internal surface of all components of the cardiovascular system is lined by simple squamous epithelium.',
     ['A) True', 'B) False'],
     'A',
     'All blood vessels, lymphatics, and heart chambers are lined by ENDOTHELIUM — a monolayer of simple squamous epithelial cells. Endothelium regulates vasomotor tone, prevents thrombosis, and controls permeability.',
     True),

    ('H','tf',
     'Pericytes are found in the wall of ALL blood vessels.',
     ['A) True', 'B) False'],
     'B',
     'Pericytes are associated specifically with CAPILLARIES and postcapillary VENULES — NOT all vessels. Larger vessels have smooth muscle cells in their tunica media. Pericytes regulate capillary diameter and support angiogenesis.',
     True),

    ('H','mcq',
     'The thickest layer in the wall of ARTERIES is the:',
     ['A) Tunica intima',
      'B) Tunica media',
      'C) Tunica adventitia',
      'D) Basement membrane'],
     'B',
     'ARTERIES: thickest = tunica MEDIA (smooth muscle + elastic fibers) — resists high pressure. VEINS: thickest = tunica ADVENTITIA (connective tissue). Capillaries = only tunica intima (endothelium + basement membrane).',
     True),

    ('H','mcq',
     'The lining of lymphatic vessels is composed of which cell type?',
     ['A) Stratified squamous epithelium',
      'B) Simple columnar epithelium',
      'C) Pseudostratified columnar epithelium',
      'D) Simple squamous epithelium'],
     'D',
     'Lymphatic vessels are lined by SIMPLE SQUAMOUS endothelium (same lineage as blood vessel endothelium). They have NO continuous basement membrane, making them more permeable. Absent in CNS, bone marrow, cartilage, cornea.',
     True),

    ('H','mcq',
     'The most immature recognizable cell in the myeloid series is the:',
     ['A) Metamyelocyte',
      'B) Myelocyte',
      'C) Promyelocyte',
      'D) Myeloblast'],
     'D',
     'Myeloid development: MYELOBLAST → Promyelocyte → Myelocyte → Metamyelocyte → Band cell → Mature granulocyte. The myeloblast is the first recognizable committed myeloid cell by morphology.',
     True),

    ('H','tf',
     'Pulmonary surfactant prevents alveolar collapse by INCREASING surface tension.',
     ['A) True', 'B) False'],
     'B',
     'Surfactant DECREASES (REDUCES) surface tension of the fluid lining alveoli — this prevents collapse. It is produced by TYPE II PNEUMOCYTES (septal cells). Deficiency causes RDS (hyaline membrane disease) in premature infants.',
     True),

    ('H','mcq',
     'Which cells are found in large numbers in the terminal bronchioles?',
     ['A) Type I pneumocytes',
      'B) Goblet cells',
      'C) Clara (Club) cells',
      'D) Alveolar macrophages'],
     'C',
     'Clara cells (Club cells): non-ciliated, dome-shaped cells in terminal bronchioles. They produce surfactant-like compounds, detoxify inhaled substances, and act as progenitor stem cells for bronchiolar epithelium.',
     True),

    ('H','mcq',
     'The connective tissue of the trachea is derived from:',
     ['A) Surface ectoderm',
      'B) Paraxial mesoderm',
      'C) Neural crest cells',
      'D) Splanchnic mesenchyme'],
     'D',
     'Tracheal EPITHELIUM = endodermal. CARTILAGE and CONNECTIVE TISSUE = splanchnic mesenchyme (splanchnic lateral plate mesoderm). This is the same origin as gut smooth muscle and connective tissue.',
     True),

    ('H','mcq',
     'The laryngotracheal diverticulum maintains communication with what structure through the primordial laryngeal inlet?',
     ['A) Esophagus',
      'B) Primordial pharynx',
      'C) Sinus venosus',
      'D) Foregut'],
     'B',
     'The laryngotracheal diverticulum grows from the ventral wall of the PRIMORDIAL PHARYNX. It maintains communication through the laryngeal inlet. The tracheoesophageal septum separates it from the esophagus dorsally.',
     True),

    ('H','tf',
     'Before birth, the primordial alveoli appear as small bulges on the walls of terminal bronchioles.',
     ['A) True', 'B) False'],
     'B',
     'Primordial alveoli appear as bulges on walls of RESPIRATORY BRONCHIOLES and alveolar SACS (NOT terminal bronchioles). They develop in the alveolar stage (~36 weeks to birth). Alveoli multiply rapidly after birth.',
     True),

    # ══════════ PHYSIOLOGY ══════════
    ('P','mcq',
     'The correct formula for calculating cardiac output is:',
     ['A) CO = Stroke volume ÷ Heart rate',
      'B) CO = Heart rate × Stroke volume',
      'C) CO = End-diastolic volume − End-systolic volume',
      'D) CO = Blood pressure ÷ Vascular resistance'],
     'B',
     'CO = HR × SV. Normal ≈ 5 L/min (70 bpm × 70 mL). SV = EDV − ESV. Ejection fraction = SV/EDV × 100% (normal 55-70%). Cardiac index = CO / body surface area.',
     True),

    ('P','mcq',
     'The correct sequence of the cardiac conduction system is:',
     ['A) AV node → SA node → Bundle of His → Purkinje fibers',
      'B) SA node → AV node → Bundle of His → Bundle branches → Purkinje fibers',
      'C) SA node → Bundle of His → AV node → Purkinje fibers',
      'D) SA node → AV node → Purkinje fibers → Bundle of His'],
     'B',
     'SA node (60-100 bpm) → AV node (delays ~0.1 sec) → Bundle of His → Left + Right bundle branches → Purkinje fibers (fastest conduction: 1-4 m/s) → Ventricles. The AV node allows atrial contraction before ventricular.',
     True),

    ('P','mcq',
     'Acetylcholine (vagal stimulation) causes which effect on the SA node?',
     ['A) Depolarization, increasing heart rate',
      'B) Increased calcium influx, increasing contraction',
      'C) Hyperpolarization, decreasing heart rate',
      'D) Repolarization, causing arrhythmias'],
     'C',
     'ACh → M2 receptors → opens IKACh (K+ channels) → hyperpolarization → slower pacemaker depolarization → ↓HR. Opposite: NE/sympathetic → β1 receptors → ↑If and Ca²⁺ currents → ↑HR.',
     True),

    ('P','mcq',
     'Cardiac weakness can be caused by deficiency of which substance in the extracellular fluid?',
     ['A) Sodium',
      'B) Chloride',
      'C) Calcium',
      'D) Bicarbonate'],
     'C',
     'Ca²⁺ is essential for cardiac muscle contraction (enters via L-type channels → triggers Ca²⁺-induced Ca²⁺ release from SR). Most Ca²⁺ for cardiac muscle comes from EXTRACELLULAR space. Hypocalcemia → reduced contractility.',
     True),

    ('P','mcq',
     'Active hyperemia occurs when the tissue _____ rate increases:',
     ['A) Respiration',
      'B) Metabolic',
      'C) Filtration',
      'D) Excretion'],
     'B',
     'Active (functional) hyperemia: ↑metabolism → local vasodilatory metabolites (CO₂, adenosine, K⁺, H⁺, ↓O₂) → vasodilation → ↑blood flow. Classic example: skeletal muscle during exercise.',
     True),

    ('P','mcq',
     'Veins are called capacitance vessels because they:',
     ['A) Have the highest blood flow velocity',
      'B) Contain the greatest percentage (~64%) of total blood volume',
      'C) Generate the most blood pressure',
      'D) Have the thickest walls in the vasculature'],
     'B',
     'Veins are highly compliant and contain ~64% of total blood volume. Arteries = pressure vessels. Capillaries = exchange vessels. Arterioles = resistance vessels. Veins serve as blood reservoirs.',
     True),

    ('P','mcq',
     'Arterial blood pressure is a product of:',
     ['A) Heart rate and stroke volume only',
      'B) Cardiac output and total peripheral resistance',
      'C) Blood volume and venous return',
      'D) Heart rate and blood viscosity'],
     'B',
     'MAP = CO × SVR (systemic vascular resistance). BP = CO × TPR. Both cardiac output (HR × SV) and total peripheral resistance (mainly arterioles) must be addressed to treat hypertension.',
     True),

    ('P','mcq',
     'According to Poiseuille\'s law, which factor has the GREATEST impact on vascular resistance?',
     ['A) Blood viscosity (η)',
      'B) Vessel length (L)',
      'C) Vessel radius (r) — to the 4th power',
      'D) Blood density'],
     'C',
     'Resistance = 8ηL / πr⁴. Radius has the dominant effect (r⁴). Halving the radius increases resistance 16-fold (2⁴=16). This is why arterioles (which can constrict/dilate) are the primary regulators of blood flow distribution.',
     True),

    ('P','mcq',
     'The structure that opens and closes the entrance to a capillary bed is the:',
     ['A) Metarteriole',
      'B) Arteriole',
      'C) Precapillary sphincter',
      'D) Thoroughfare channel'],
     'C',
     'Precapillary sphincters are smooth muscle rings at the origin of capillaries. The most important factor controlling them = tissue O₂ concentration (↓O₂ → sphincters OPEN → more blood flow = autoregulation).',
     True),

    ('P','mcq',
     'During isovolumetric relaxation time (IVRT), which statement is correct?',
     ['A) Only the mitral valve is open',
      'B) Only the aortic valve is open',
      'C) Both mitral and aortic valves are closed',
      'D) Both mitral and aortic valves are open'],
     'C',
     'IVRT = period from AORTIC valve closure to MITRAL valve opening. Ventricular pressure drops rapidly but no valves are open → volume stays constant. IVRT ends when ventricular pressure falls below atrial pressure.',
     True),

    ('P','mcq',
     'The "a" wave on the atrial pressure/JVP curve is caused by:',
     ['A) Tricuspid valve closure',
      'B) Ventricular systole',
      'C) Atrial contraction',
      'D) Venous filling of the atrium'],
     'C',
     'JVP waves: "a" = ATRIAL CONTRACTION | "c" = tricuspid bulging into RA | "x" = atrial relaxation | "v" = venous filling during ventricular systole | "y" = tricuspid opening. The "a" wave is absent in atrial fibrillation.',
     True),

    ('P','mcq',
     'The Frank-Starling law states that:',
     ['A) Heart rate is directly proportional to blood pressure',
      'B) The greater the venous return, the stronger the ventricular contraction and the greater the stroke volume',
      'C) Stroke volume is inversely proportional to end-diastolic volume',
      'D) Cardiac output is independent of preload'],
     'B',
     'Frank-Starling: ↑venous return → ↑EDV → ↑myocardial fiber stretch → ↑force of contraction → ↑SV → ↑CO. The heart automatically pumps whatever blood it receives. This intrinsic mechanism needs no neural input.',
     True),

    ('P','mcq',
     'Coronary blood flow mostly occurs during which phase of the cardiac cycle?',
     ['A) Isovolumetric contraction',
      'B) Systole',
      'C) Diastole',
      'D) Isovolumetric relaxation'],
     'C',
     'Left coronary flow is mainly in DIASTOLE — the contracting myocardium compresses left coronary vessels during systole, reducing flow. High HR shortens diastole → less filling time → risk of ischemia. Right coronary is less affected.',
     True),

    ('P','mcq',
     'Afterload for the LEFT ventricle is equivalent to:',
     ['A) End-diastolic ventricular volume',
      'B) Central venous pressure',
      'C) Aortic pressure (systemic vascular resistance)',
      'D) Pulmonary artery pressure'],
     'C',
     'Afterload = resistance against which the ventricle pumps. LV afterload = AORTIC PRESSURE / SVR. RV afterload = pulmonary artery pressure. ↑Afterload (e.g., hypertension, aortic stenosis) → ↓SV → LV hypertrophy.',
     True),

    ('P','tf',
     'Cardiac tamponade increases cardiac output.',
     ['A) True', 'B) False'],
     'B',
     'Cardiac tamponade = pericardial fluid compresses the heart → impaired diastolic filling → ↓CO. Beck\'s triad: (1) hypotension, (2) muffled heart sounds, (3) distended neck veins. Treatment: urgent pericardiocentesis.',
     True),

    ('P','tf',
     'Collateral coronary flow can damage the myocardium.',
     ['A) True', 'B) False'],
     'B',
     'Collateral vessels PROTECT the myocardium by providing alternative blood supply routes around blocked coronary arteries. The more developed the collaterals, the smaller the infarct. Collateral flow ≠ reperfusion injury.',
     True),

    ('P','mcq',
     'Pulse pressure is defined as:',
     ['A) Mean arterial pressure divided by diastolic pressure',
      'B) The difference between systolic and diastolic blood pressure',
      'C) The product of heart rate and stroke volume',
      'D) Systolic pressure divided by diastolic pressure'],
     'B',
     'Pulse pressure = Systolic BP − Diastolic BP (normal ≈ 40 mmHg). MAP = DBP + (PP/3) ≈ 93 mmHg. Pulse pressure is highest in LARGE ARTERIES and diminishes progressively toward capillaries/veins.',
     True),

    ('P','mcq',
     'The normal right atrial pressure is approximately:',
     ['A) 0 mmHg',
      'B) 10 mmHg',
      'C) 25 mmHg',
      'D) 80 mmHg'],
     'A',
     'Normal pressures: RA ≈ 0 mmHg | RV systolic = 25 mmHg | Pulmonary artery systolic = 25 mmHg | LA = 5-10 mmHg | LV systolic = 120 mmHg | Aorta = 120/80 mmHg. RA pressure ≈ CVP (central venous pressure).',
     True),

    ('P','mcq',
     'Edema is BEST described as:',
     ['A) Decreased plasma volume',
      'B) Accumulation of excess fluid in the interstitium',
      'C) Increased lymphatic flow',
      'D) Decreased capillary hydrostatic pressure'],
     'B',
     'Edema = excess fluid in interstitial space. Causes: (1) ↑capillary hydrostatic P (heart failure), (2) ↓plasma oncotic P (hypoalbuminemia), (3) lymphatic obstruction, (4) ↑capillary permeability (inflammation). ALL are valid causes.',
     True),

    ('P','mcq',
     'Lymph capillaries differ from systemic blood capillaries in that they:',
     ['A) Are present in the central nervous system',
      'B) Have continuous basement membranes',
      'C) Are absent in the central nervous system',
      'D) Are lined by stratified squamous epithelium'],
     'C',
     'Lymph capillaries are absent in: CNS, bone marrow, avascular tissues (cartilage, cornea). They are blind-ended, lack a continuous basement membrane (more permeable), and pick up excess interstitial fluid + proteins.',
     True),

    ('P','mcq',
     'Flow of fluid through the lymphatic vessels will be DECREASED if there is an increase in:',
     ['A) Capillary hydrostatic pressure',
      'B) Capillary permeability',
      'C) Capillary oncotic pressure',
      'D) Interstitial fluid volume'],
     'C',
     '↑Capillary oncotic pressure → more fluid is reabsorbed BACK into the capillary (by osmosis) → LESS fluid enters lymphatics → decreased lymph flow. Conversely, ↑hydrostatic pressure → more filtration → more lymph.',
     True),

    ('P','mcq',
     'The PQ (PR) interval on ECG represents:',
     ['A) Ventricular depolarization',
      'B) Ventricular repolarization',
      'C) AV nodal conduction time',
      'D) Atrial repolarization'],
     'C',
     'PR interval = onset of P wave to onset of QRS = AV conduction time (normal 0.12-0.20 sec). Prolonged PR = 1st degree AV block. Short PR (< 0.12 sec) = WPW syndrome (accessory pathway bypasses AV node).',
     True),

    ('P','tf',
     'Vagal stimulation of the SA node increases Ca²⁺ influx into pacemaker cells.',
     ['A) True', 'B) False'],
     'B',
     'Vagal stimulation releases ACh → M2 receptors → ↑K⁺ permeability (IKACh) → HYPERPOLARIZATION → slower rate. Ca²⁺ influx is DECREASED (not increased). Sympathetic stimulation INCREASES Ca²⁺ and funny (If) channel activity.',
     True),

    ('P','mcq',
     'Norepinephrine stimulates _____ receptors, which mediate effects on heart rate:',
     ['A) Alpha-1 adrenergic receptors',
      'B) Muscarinic receptors',
      'C) Beta-2 adrenergic receptors',
      'D) Beta-1 adrenergic receptors'],
     'D',
     'Beta-1 (β1) receptors are in the HEART. NE/Epi → β1 → ↑HR (chronotropy), ↑contractility (inotropy), ↑conduction speed (dromotropy). β2 = lungs (bronchodilation) + vessels (vasodilation). α1 = vessels (vasoconstriction).',
     True),

    ('P','tf',
     'Peripheral chemoreceptors are located in the carotid sinus and aortic arch.',
     ['A) True', 'B) False'],
     'B',
     'Peripheral O₂ chemoreceptors = carotid BODY + aortic BODIES. The carotid SINUS is a BARORECEPTOR (senses pressure, not O₂). Central chemoreceptors (in the brainstem) sense CO₂ and pH, not O₂.',
     True),

    ('P','mcq',
     'The velocity of blood flow is slowest in capillaries because:',
     ['A) They have the thickest walls',
      'B) They carry the least total blood volume',
      'C) They have the largest total cross-sectional area',
      'D) Their blood pressure is the highest'],
     'C',
     'Velocity ∝ 1/total cross-sectional area. Capillaries have the LARGEST total CSA → SLOWEST velocity. Aorta = smallest CSA → fastest velocity. Slow capillary flow allows maximum time for O₂/nutrient exchange.',
     True),

    ('P','mcq',
     'The smaller the alveolus, the _____ the alveolar pressure due to surface tension (Law of Laplace):',
     ['A) Lower',
      'B) Greater',
      'C) Equal',
      'D) Negligible'],
     'B',
     'Law of Laplace: P = 2T/r. Smaller radius → GREATER pressure → tendency to collapse into larger alveoli. Surfactant reduces T more in smaller alveoli (higher concentration) → stabilises all alveoli equally.',
     True),

    ('P','mcq',
     'How to distinguish pericarditis from myocardial infarction clinically?',
     ['A) Pericarditis pain radiates to the left arm',
      'B) Pericarditis pain is relieved by sitting/leaning forward',
      'C) Pericarditis causes ST depression in all leads',
      'D) Pericarditis presents with a Q wave on ECG'],
     'B',
     'Pericarditis: sharp, pleuritic pain, worse lying flat, RELIEVED leaning forward (reduces friction between pericardial layers). MI: crushing pain, radiates to left arm/jaw, NOT relieved by position. Friction rub = pericarditis.',
     True),

    ('P','mcq',
     'Most carbon dioxide (~70%) is transported from tissues in the blood as:',
     ['A) Dissolved CO₂',
      'B) Carbaminohemoglobin',
      'C) Bicarbonate ions (HCO₃⁻)',
      'D) Carbonic acid'],
     'C',
     'CO₂ transport: 70% as HCO₃⁻ (CO₂+H₂O→H₂CO₃→H⁺+HCO₃⁻, catalysed by carbonic anhydrase in RBCs), 23% as carbaminoHb, 7% dissolved. The HCO₃⁻ is exchanged for Cl⁻ (chloride shift).',
     True),
]

# ── SHUFFLE ───────────────────────────────────────────────────────────────────
random.shuffle(QUESTIONS)

# ── helper styles ─────────────────────────────────────────────────────────────
sH1  = S('sH1', fontSize=22, textColor=C_WHITE, fontName='Helvetica-Bold',
          alignment=TA_CENTER, leading=26, spaceAfter=4)
sH2  = S('sH2', fontSize=13, textColor=colors.HexColor('#90CAF9'),
          fontName='Helvetica', alignment=TA_CENTER, leading=16)
sHdr = S('sHdr', fontSize=11, textColor=C_WHITE, fontName='Helvetica-Bold',
          alignment=TA_CENTER, leading=14)
sQnum= S('sQnum', fontSize=13, textColor=C_WHITE, fontName='Helvetica-Bold',
          alignment=TA_CENTER, leading=16)
sStem= S('sStem', fontSize=11, textColor=C_DARK, fontName='Helvetica-Bold',
          leading=15, spaceAfter=4)
sOpt = S('sOpt', fontSize=10.5, textColor=C_DARK, fontName='Helvetica',
          leading=14, leftIndent=8, spaceAfter=1)
sTag2= S('sTag2', fontSize=7.5, textColor=C_WHITE, fontName='Helvetica-Bold',
          alignment=TA_CENTER, leading=9)
sSmall=S('sSmall', fontSize=8, textColor=C_MID, fontName='Helvetica',
          alignment=TA_RIGHT, leading=10)
sAnsHdr=S('sAnsHdr',fontSize=12,textColor=C_WHITE,fontName='Helvetica-Bold',
           alignment=TA_CENTER,leading=15)
sAnsQ= S('sAnsQ', fontSize=10, textColor=C_DARK, fontName='Helvetica-Bold', leading=14)
sAnsC= S('sAnsC', fontSize=10, textColor=C_GREEN, fontName='Helvetica-Bold', leading=14)
sAnsE= S('sAnsE', fontSize=9, textColor=C_DARK, fontName='Helvetica',
          leading=13, leftIndent=8)
sBox = S('sBox', fontSize=9, textColor=C_DARK, fontName='Helvetica',
          leading=13, alignment=TA_CENTER)
sRepPh= S('sRepPh', fontSize=7.5, textColor=C_GOLD, fontName='Helvetica-Bold',
           alignment=TA_LEFT, leading=9)
sCovSub=S('sCovSub',fontSize=11,textColor=colors.HexColor('#AACCEE'),
           fontName='Helvetica',alignment=TA_CENTER,leading=14)

W = PAGE_W - 2*MARGIN

def subj_tag_cell(subj, repeated):
    hdr_c, bg_c, label = SUBJ_COLORS[subj]
    tag_text = f'⭐ REPEATED  |  {label}' if repeated else label
    tc = Table([[Paragraph(tag_text, sTag2)]], colWidths=[W])
    tc.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), hdr_c),
        ('TOPPADDING',(0,0),(-1,-1),3),
        ('BOTTOMPADDING',(0,0),(-1,-1),3),
    ]))
    return tc

def build_question_block(num, subj, qtype, stem, opts, correct, expl, repeated):
    hdr_c, bg_c, label = SUBJ_COLORS[subj]

    # number badge
    num_tab = Table([[Paragraph(str(num), sQnum)]], colWidths=[1.1*cm], rowHeights=[1.1*cm])
    num_tab.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1),hdr_c),
        ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
        ('TOPPADDING',(0,0),(-1,-1),0),
        ('BOTTOMPADDING',(0,0),(-1,-1),0),
    ]))

    # TF badge
    tf_label = 'TRUE / FALSE' if qtype=='tf' else 'MCQ'
    type_tab = Table([[Paragraph(tf_label, sTag2)]], colWidths=[1.8*cm], rowHeights=[1.1*cm])
    type_tab.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), C_GOLD if qtype=='tf' else C_BLUE),
        ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
        ('TOPPADDING',(0,0),(-1,-1),0),
        ('BOTTOMPADDING',(0,0),(-1,-1),0),
    ]))

    # subject tag
    tag_text = f'⭐ {label}' if repeated else label
    subj_tab = Table([[Paragraph(tag_text, sTag2)]], colWidths=[W-1.1*cm-1.8*cm-0.4*cm],
                      rowHeights=[1.1*cm])
    subj_tab.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), hdr_c),
        ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
        ('TOPPADDING',(0,0),(-1,-1),0),
        ('BOTTOMPADDING',(0,0),(-1,-1),0),
        ('ALIGN',(0,0),(-1,-1),'RIGHT'),
    ]))

    header = Table([[num_tab, type_tab, Spacer(0.2*cm,1), subj_tab]],
                    colWidths=[1.1*cm, 1.8*cm, 0.2*cm, W-1.1*cm-1.8*cm-0.2*cm])
    header.setStyle(TableStyle([
        ('VALIGN',(0,0),(-1,-1),'TOP'),
        ('LEFTPADDING',(0,0),(-1,-1),0),
        ('RIGHTPADDING',(0,0),(-1,-1),0),
        ('TOPPADDING',(0,0),(-1,-1),0),
        ('BOTTOMPADDING',(0,0),(-1,-1),0),
    ]))

    # stem + options
    rows = [[Paragraph(stem, sStem)]]
    rows.append([Spacer(1, 3)])
    for opt in opts:
        rows.append([Paragraph(opt, sOpt)])
    # answer blank
    rows.append([Spacer(1, 4)])
    rows.append([Paragraph('My answer: ______', S(f'blank{num}', fontSize=9.5,
                  textColor=C_MID, fontName='Helvetica-Oblique', leading=14))])

    body = Table(rows, colWidths=[W])
    body.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1),C_WHITE),
        ('TOPPADDING',(0,0),(-1,-1),5),
        ('BOTTOMPADDING',(0,0),(-1,-1),2),
        ('LEFTPADDING',(0,0),(-1,-1),10),
        ('RIGHTPADDING',(0,0),(-1,-1),10),
        ('LINEBELOW',(0,-1),(-1,-1),0.5,C_LITE),
    ]))

    card = Table([[header],[body]], colWidths=[W])
    card.setStyle(TableStyle([
        ('BOX',(0,0),(-1,-1),1.2, hdr_c),
        ('TOPPADDING',(0,0),(-1,-1),0),
        ('BOTTOMPADDING',(0,0),(-1,-1),0),
        ('LEFTPADDING',(0,0),(-1,-1),0),
        ('RIGHTPADDING',(0,0),(-1,-1),0),
    ]))
    return card

def build_answer_block(num, subj, qtype, stem_short, correct, expl):
    hdr_c, bg_c, label = SUBJ_COLORS[subj]
    opt_letter = correct
    rows = [
        [Paragraph(f'<b>Q{num}.</b> {stem_short[:80]}{"..." if len(stem_short)>80 else ""}', sAnsQ)],
        [Paragraph(f'✔  Correct Answer: <b>{opt_letter}</b>', sAnsC)],
        [Paragraph(expl, sAnsE)],
        [Spacer(1,3)],
    ]
    body = Table(rows, colWidths=[W])
    body.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,0), bg_c),
        ('BACKGROUND',(0,1),(-1,1), C_LIME),
        ('BACKGROUND',(0,2),(-1,2), C_GREY),
        ('TOPPADDING',(0,0),(-1,-1),4),
        ('BOTTOMPADDING',(0,0),(-1,-1),4),
        ('LEFTPADDING',(0,0),(-1,-1),8),
        ('RIGHTPADDING',(0,0),(-1,-1),8),
        ('LINEBELOW',(0,-1),(-1,-1),0.5,hdr_c),
    ]))
    return body

# ── BUILD PDF ─────────────────────────────────────────────────────────────────
doc = SimpleDocTemplate(
    OUTPUT_EXAM, pagesize=A4,
    leftMargin=MARGIN, rightMargin=MARGIN,
    topMargin=MARGIN, bottomMargin=MARGIN,
    title='Human Body Finals — Practice Exam',
    author='Orris AI'
)
story = []

# ── COVER ─────────────────────────────────────────────────────────────────────
cover = Table([
    [Paragraph('📝  PRACTICE EXAM', sH1)],
    [Paragraph('Human Body Systems — Finals Preparation', sH2)],
    [Spacer(1, 0.3*cm)],
    [Paragraph('Anatomy  •  Histology & Embryology  •  Physiology', sCovSub)],
    [Spacer(1, 0.5*cm)],
    [Paragraph(f'<b>{len(QUESTIONS)} Questions</b>  (MCQ + True/False)  •  Questions in random order  •  Answer Key at end',
               S('cI', fontSize=10, textColor=colors.HexColor('#90CAF9'),
                 fontName='Helvetica', alignment=TA_CENTER, leading=14))],
    [Spacer(1, 0.4*cm)],
    [Table([
        [Paragraph('📋  INSTRUCTIONS', S('iH',fontSize=11,textColor=C_GOLD,fontName='Helvetica-Bold',alignment=TA_LEFT,leading=14))],
        [Paragraph(
            '• For MCQ: circle or write the letter (A / B / C / D) of the best answer.\n'
            '• For True/False: write A for True, B for False.\n'
            '• ⭐ = appeared in multiple past exams — highest priority.\n'
            '• 🟦 Navy border = Anatomy  |  🟪 Purple = Histo/Embryo  |  🟩 Teal = Physiology\n'
            '• Time yourself: aim for ~1 minute per question.',
            S('iB',fontSize=9,textColor=colors.HexColor('#CCDFF5'),
              fontName='Helvetica',alignment=TA_LEFT,leading=13))],
    ], colWidths=[W-3*cm])],
], colWidths=[W])
cover.setStyle(TableStyle([
    ('BACKGROUND',(0,0),(-1,-1),colors.HexColor('#0D2B4E')),
    ('TOPPADDING',(0,0),(-1,-1),10),
    ('BOTTOMPADDING',(0,0),(-1,-1),10),
    ('LEFTPADDING',(0,0),(-1,-1),20),
    ('RIGHTPADDING',(0,0),(-1,-1),20),
    ('LINEBELOW',(0,1),(0,1),1,C_BLUE),
    ('LINEBELOW',(0,5),(0,5),1,C_BLUE),
    ('ROUNDEDCORNERS',(0,0),(-1,-1),[8,8,8,8]),
]))
story.append(cover)
story.append(Spacer(1, 0.4*cm))

# summary stats
anat_n = sum(1 for q in QUESTIONS if q[0]=='A')
hist_n = sum(1 for q in QUESTIONS if q[0]=='H')
phys_n = sum(1 for q in QUESTIONS if q[0]=='P')
rep_n  = sum(1 for q in QUESTIONS if q[6])
mcq_n  = sum(1 for q in QUESTIONS if q[1]=='mcq')
tf_n   = sum(1 for q in QUESTIONS if q[1]=='tf')

stats = Table([[
    Paragraph(f'🟦 Anatomy\n<b>{anat_n} Qs</b>', sBox),
    Paragraph(f'🟪 Histo/Emb\n<b>{hist_n} Qs</b>', sBox),
    Paragraph(f'🟩 Physiology\n<b>{phys_n} Qs</b>', sBox),
    Paragraph(f'🔵 MCQ\n<b>{mcq_n} Qs</b>', sBox),
    Paragraph(f'🟡 True/False\n<b>{tf_n} Qs</b>', sBox),
    Paragraph(f'⭐ Repeated\n<b>{rep_n} Qs</b>', sBox),
]], colWidths=[W/6]*6)
stats.setStyle(TableStyle([
    ('BACKGROUND',(0,0),(0,0), C_SKY),
    ('BACKGROUND',(1,0),(1,0), C_LAV),
    ('BACKGROUND',(2,0),(2,0), C_TEAL_L),
    ('BACKGROUND',(3,0),(3,0), colors.HexColor('#E0EEFF')),
    ('BACKGROUND',(4,0),(4,0), C_YELLOW),
    ('BACKGROUND',(5,0),(5,0), colors.HexColor('#FFF3CD')),
    ('INNERGRID',(0,0),(-1,-1),0.5,C_LITE),
    ('BOX',(0,0),(-1,-1),0.5,C_LITE),
    ('TOPPADDING',(0,0),(-1,-1),6),
    ('BOTTOMPADDING',(0,0),(-1,-1),6),
    ('ALIGN',(0,0),(-1,-1),'CENTER'),
    ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
]))
story.append(stats)
story.append(PageBreak())

# ── QUESTIONS ─────────────────────────────────────────────────────────────────
for i, (subj, qtype, stem, opts, correct, expl, repeated) in enumerate(QUESTIONS):
    block = build_question_block(i+1, subj, qtype, stem, opts, correct, expl, repeated)
    story.append(KeepTogether([block, Spacer(1, 0.5*cm)]))

# ── ANSWER SHEET ─────────────────────────────────────────────────────────────
story.append(PageBreak())
ans_sheet_hdr = Table([[Paragraph('📋  QUICK ANSWER SHEET', sAnsHdr)]],
                       colWidths=[W])
ans_sheet_hdr.setStyle(TableStyle([
    ('BACKGROUND',(0,0),(-1,-1),C_NAVY),
    ('TOPPADDING',(0,0),(-1,-1),8),
    ('BOTTOMPADDING',(0,0),(-1,-1),8),
    ('ROUNDEDCORNERS',(0,0),(-1,-1),[6,6,0,0]),
]))
story.append(ans_sheet_hdr)
story.append(Spacer(1,0.15*cm))

# build grid: 10 per row
grid_rows = []
COLS = 10
for row_start in range(0, len(QUESTIONS), COLS):
    num_row = []
    ans_row = []
    for j in range(COLS):
        idx = row_start + j
        if idx < len(QUESTIONS):
            subj, qtype, stem, opts, correct, expl, repeated = QUESTIONS[idx]
            hdr_c, _, _ = SUBJ_COLORS[subj]
            num_row.append(Paragraph(f'<b>Q{idx+1}</b>', S(f'gs{idx}', fontSize=8,
                           textColor=C_WHITE, fontName='Helvetica-Bold', alignment=TA_CENTER)))
            ans_row.append(Paragraph('___', S(f'ga{idx}', fontSize=9,
                           textColor=C_DARK, fontName='Helvetica', alignment=TA_CENTER)))
        else:
            num_row.append(Paragraph('', sBox))
            ans_row.append(Paragraph('', sBox))
    grid_rows.append(num_row)
    grid_rows.append(ans_row)

col_w = W / COLS
grid = Table(grid_rows, colWidths=[col_w]*COLS)
grid_style = [
    ('INNERGRID',(0,0),(-1,-1),0.4,C_LITE),
    ('BOX',(0,0),(-1,-1),0.8,C_NAVY),
    ('TOPPADDING',(0,0),(-1,-1),4),
    ('BOTTOMPADDING',(0,0),(-1,-1),4),
    ('ALIGN',(0,0),(-1,-1),'CENTER'),
    ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
]
# Colour number rows
for row_start in range(0, len(QUESTIONS), COLS):
    row_idx = (row_start // COLS) * 2
    grid_style.append(('BACKGROUND',(0,row_idx),(-1,row_idx), C_NAVY))
    grid_style.append(('BACKGROUND',(0,row_idx+1),(-1,row_idx+1), C_GREY))
grid.setStyle(TableStyle(grid_style))
story.append(grid)
story.append(Spacer(1,0.3*cm))
story.append(Paragraph('Fill in your answers above, then check against the Answer Key on the next pages.',
    S('hint', fontSize=9, textColor=C_MID, fontName='Helvetica-Oblique',
      alignment=TA_CENTER, leading=12)))

# ── ANSWER KEY ────────────────────────────────────────────────────────────────
story.append(PageBreak())
key_hdr = Table([[Paragraph('🔑  ANSWER KEY  WITH  EXPLANATIONS', sAnsHdr)]],
                 colWidths=[W])
key_hdr.setStyle(TableStyle([
    ('BACKGROUND',(0,0),(-1,-1),C_GREEN),
    ('TOPPADDING',(0,0),(-1,-1),10),
    ('BOTTOMPADDING',(0,0),(-1,-1),10),
    ('ROUNDEDCORNERS',(0,0),(-1,-1),[6,6,0,0]),
]))
story.append(key_hdr)
story.append(Spacer(1,0.2*cm))

for i, (subj, qtype, stem, opts, correct, expl, repeated) in enumerate(QUESTIONS):
    # find option text for correct letter
    correct_text = next((o for o in opts if o.startswith(f'{correct})')), correct)
    block = build_answer_block(i+1, subj, qtype, stem, correct_text, expl)
    story.append(KeepTogether([block]))

story.append(Spacer(1,0.4*cm))

# ── SCORE GUIDE ───────────────────────────────────────────────────────────────
total = len(QUESTIONS)
score_data = [
    [Paragraph('<b>Score</b>', sBox),
     Paragraph(f'<b>{int(total*0.9)}-{total}</b>', sBox),
     Paragraph(f'<b>{int(total*0.75)}-{int(total*0.9)-1}</b>', sBox),
     Paragraph(f'<b>{int(total*0.6)}-{int(total*0.75)-1}</b>', sBox),
     Paragraph(f'<b>Below {int(total*0.6)}</b>', sBox)],
    [Paragraph('<b>Grade</b>', sBox),
     Paragraph('🏆 Excellent', sBox),
     Paragraph('✅ Good', sBox),
     Paragraph('⚠️ Review needed', sBox),
     Paragraph('❌ Must restudy', sBox)],
]
score_tab = Table(score_data, colWidths=[W/5]*5)
score_tab.setStyle(TableStyle([
    ('BACKGROUND',(0,0),(-1,0), C_NAVY),
    ('TEXTCOLOR',(0,0),(-1,0), C_WHITE),
    ('BACKGROUND',(1,1),(1,1), C_LIME),
    ('BACKGROUND',(2,1),(2,1), C_SKY),
    ('BACKGROUND',(3,1),(3,1), C_YELLOW),
    ('BACKGROUND',(4,1),(4,1), C_PINK),
    ('INNERGRID',(0,0),(-1,-1),0.5,C_LITE),
    ('BOX',(0,0),(-1,-1),1,C_NAVY),
    ('TOPPADDING',(0,0),(-1,-1),6),
    ('BOTTOMPADDING',(0,0),(-1,-1),6),
    ('ALIGN',(0,0),(-1,-1),'CENTER'),
    ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
]))
story.append(score_tab)

doc.build(story)
print(f'Done → {OUTPUT_EXAM}')
print(f'Total questions: {total}  |  MCQ: {mcq_n}  |  T/F: {tf_n}  |  Repeated: {rep_n}')

from reportlab.lib.pagesizes import A4
from reportlab.lib import colors
from reportlab.lib.units import cm
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle,
    PageBreak, KeepTogether
)
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.lib.enums import TA_CENTER, TA_LEFT, TA_RIGHT

OUTPUT = '/tmp/workspace/finals-study-guide/TOP30_LAST_MINUTE.pdf'
PAGE_W, PAGE_H = A4
M = 1.5 * cm
W = PAGE_W - 2 * M

# ── palette ───────────────────────────────────────────────────────────────────
CN   = colors.HexColor('#0D2A4E')   # deep navy
CB   = colors.HexColor('#1668B0')   # blue
CSK  = colors.HexColor('#DFF0FF')   # sky
CPU  = colors.HexColor('#4A006A')   # purple
CLAV = colors.HexColor('#F0E8FF')   # lavender
CTL  = colors.HexColor('#005850')   # teal
CTLL = colors.HexColor('#DCF5F2')   # teal light
CRD  = colors.HexColor('#B30000')   # red
CPK  = colors.HexColor('#FFF0F0')   # pink bg
CGN  = colors.HexColor('#1A5C28')   # green
CLM  = colors.HexColor('#E8F8EE')   # lime
COR  = colors.HexColor('#C04800')   # orange
CYL  = colors.HexColor('#FFF5D0')   # yellow
CGD  = colors.HexColor('#9A7200')   # gold dark
CGD2 = colors.HexColor('#FFD700')   # gold
CWH  = colors.white
CGY  = colors.HexColor('#F4F4F4')   # grey bg
CML  = colors.HexColor('#777777')   # mid grey
CLT  = colors.HexColor('#DDDDDD')   # light grey

def S(n, **k):
    return ParagraphStyle(n, parent=getSampleStyleSheet()['Normal'], **k)

# ── TOP 30 DATA ───────────────────────────────────────────────────────────────
# Format per entry:
# (rank, subj, appearances, topic_title,
#  key_fact,           ← the ONE sentence answer you must know
#  trap,               ← the wrong answer that appeared in exams
#  detail)             ← 1-2 extra lines of supporting detail
#
# subj: 'A'=Anatomy  'H'=Histo/Embryo  'P'=Physiology

TOP30 = [
    (1, 'H', 6,
     "Surfactant & Surface Tension",
     "Surfactant DECREASES surface tension, preventing alveolar collapse.",
     "TRAP: 'increases surface tension' — this is FALSE and appeared as the wrong answer 4× across files.",
     "Produced by Type II pneumocytes (septal cells). Deficiency → RDS in premature babies. "
     "Starts forming at ~20-22 weeks gestation. By LaPlace's law: smaller alveoli have greater collapse pressure — surfactant compensates."),

    (2, 'P', 6,
     "Cardiac Conduction Order",
     "SA node → AV node → Bundle of His → Bundle branches → Purkinje fibers → Ventricles",
     "TRAP: wrong orders appeared in almost every exam version (e.g. 'SA → Bundle of His → AV node').",
     "SA node = pacemaker (60-100 bpm), right atrium near SVC. AV node DELAYS 0.1 s (allows atrial emptying). "
     "Purkinje fibers conduct fastest (1-4 m/s). AV node = slowest. 'Ectopic pacemaker' = any site other than SA node."),

    (3, 'A', 6,
     "Ciliated Epithelium in Bronchioles",
     "Ciliated pseudostratified columnar epithelium is NOT found in bronchioles — this statement is FALSE.",
     "TRAP: answered TRUE in multiple exams. Ciliated pseudostratified = trachea + large bronchi ONLY.",
     "Bronchioles have simple columnar/cuboidal epithelium with CLARA (Club) cells. "
     "No cartilage in bronchioles. Clara cells: non-ciliated, dome-shaped, produce surfactant-like compounds."),

    (4, 'P', 6,
     "Collateral Coronary Flow",
     "Collateral flow PROTECTS the myocardium — it does NOT damage it.",
     "TRAP: 'collateral flow damages myocardium' appeared as the wrong answer in 4+ versions.",
     "Collateral vessels are alternative pathways that open when a coronary artery is occluded. "
     "More developed collaterals = smaller infarct. Coronary blood flow mainly occurs in DIASTOLE "
     "(myocardium compresses vessels during systole)."),

    (5, 'H', 5,
     "Fetal Cardiac Shunts & Their Adult Remnants",
     "Ductus arteriosus → Ligamentum arteriosum | Ductus venosus → Ligamentum venosum | Umbilical arteries → Medial umbilical ligaments | Umbilical vein → Lig. teres hepatis",
     "TRAP: 'ductus venosus → ligamentum arteriosum' — completely reversed. Appeared multiple times.",
     "Foramen ovale → fossa ovalis (closes when LA pressure > RA pressure at birth). "
     "Ductus arteriosus = 6th arch artery. RIGHT umbilical vein regresses; LEFT persists as definitive UV."),

    (6, 'A', 5,
     "Left vs Right Main Bronchus",
     "Left: LONGER, NARROWER, MORE HORIZONTAL (~45°). Right: shorter, wider, more vertical (~25°).",
     "TRAP: reversed — 'left is wider and more vertical' appeared in old exam versions.",
     "Foreign bodies lodge in the RIGHT bronchus (wider + more vertical). "
     "Left bronchus crosses midline. Both primary bronchi are derivatives of the lung buds at week 5."),

    (7, 'P', 5,
     "Acetylcholine Effect on SA Node",
     "ACh causes HYPERPOLARIZATION of the SA node → decreased heart rate.",
     "TRAP: 'repolarization' or 'depolarization' appeared as wrong answers. Also wrong: 'increases Ca²⁺ influx'.",
     "ACh → M2 receptors → opens IKACh (K⁺ channels) → hyperpolarization → slowed pacemaker. "
     "Opposite: NE/sympathetic → β1 → ↑If + Ca²⁺ channels → ↑HR. "
     "Vagal stimulation does NOT increase Ca²⁺ influx."),

    (8, 'H', 5,
     "Heart Chamber Septation Timing",
     "Heart chambers are partitioned (septated) during weeks 5–8, NOT the 4th week.",
     "TRAP: 'partitioned into 4 chambers during the 4th week' — FALSE. Appeared wrong 4+ times.",
     "Week 3 = heart tube forms. Week 4 = looping. Weeks 5-8 = septation completed. "
     "Outflow tract = bulbus cordis + truncus arteriosus. "
     "CV system is one of the FIRST organ systems to develop (begins week 3)."),

    (9, 'A', 5,
     "Anterior Cardiac Veins",
     "Anterior cardiac veins drain directly into the RIGHT ATRIUM — NOT into the coronary sinus.",
     "TRAP: 'great cardiac vein does not drain into coronary sinus' — wrong; it's the anterior cardiac veins.",
     "Coronary sinus receives: great, middle, small cardiac veins + oblique + posterior vein of LV. "
     "Coronary sinus is located in the posterior atrioventricular (coronary) sulcus. Drains into RA."),

    (10, 'P', 5,
     "Cardiac Output Formula",
     "CO = Heart Rate × Stroke Volume (normal ≈ 5 L/min = 70 bpm × 70 mL)",
     "TRAP: 'CO = SV ÷ HR' or 'CO = BP ÷ resistance' appeared as wrong choices.",
     "SV = EDV − ESV. Ejection fraction = SV/EDV × 100% (normal 55-70%). "
     "Frank-Starling: ↑EDV → ↑stretch → ↑SV → ↑CO. "
     "Afterload for LV = aortic pressure. Cardiac tamponade → DECREASES CO."),

    (11, 'A', 5,
     "Epicardium Identity",
     "Epicardium = visceral layer of serous pericardium (innermost layer, directly on heart).",
     "TRAP: 'parietal pericardium' or 'fibrous pericardium' — both wrong.",
     "Layer order (outside → in): Fibrous pericardium → Parietal serous pericardium → "
     "Pericardial cavity → Visceral serous pericardium (= EPICARDIUM). "
     "Pericarditis: pain relieved by leaning forward — distinguishes it from MI."),

    (12, 'P', 5,
     "Calcium & Cardiac Muscle",
     "Cardiac weakness is caused by Ca²⁺ DEFICIENCY in the extracellular fluid.",
     "TRAP: 'sodium deficiency' or 'potassium deficiency' appeared as distractors.",
     "Most Ca²⁺ for cardiac contraction enters from EXTRACELLULAR space via L-type channels "
     "(unlike skeletal muscle which mainly uses SR). Ca²⁺ → Ca²⁺-induced Ca²⁺ release from SR. "
     "K⁺ ions maintain resting membrane potential and are responsible for repolarization."),

    (13, 'H', 5,
     "Left Atrium Embryonic Origin",
     "The fetal LEFT ATRIUM is mainly derived from the primitive pulmonary vein.",
     "TRAP: 'sinus venosus' — that gives rise to the RIGHT atrium.",
     "The sinus venosus (right horn) forms the smooth part of the right atrium, SVC, IVC openings. "
     "The primitive pulmonary vein becomes incorporated into the posterior LA wall. "
     "The left sinus horn becomes the coronary sinus."),

    (14, 'A', 5,
     "Trachea: Level & Bifurcation",
     "Trachea extends C6 → T4/T5. Bifurcates at T4/T5 (sternal angle).",
     "TRAP: 'bifurcates at TIV/I or TII' appeared in old exam answer.",
     "Tracheal rings = 16-20 C-shaped HYALINE cartilage rings. Posterior wall = trachealis muscle. "
     "Elastin fibers allow shape adaptation during breathing. "
     "Carina = internal ridge at bifurcation. During quiet respiration, lung base crosses rib VIII (midaxillary line)."),

    (15, 'P', 4,
     "Isovolumetric Relaxation Time",
     "During IVRT, ALL valves are CLOSED (both mitral AND aortic).",
     "TRAP: 'mitral opens, aortic closes' — wrong. ALL valves closed during IVRT.",
     "IVRT = aortic valve closure → mitral valve opening. "
     "Ventricular pressure drops but volume stays CONSTANT. "
     "Once ventricular pressure < atrial pressure, mitral opens → rapid filling begins (~70% of ventricular filling)."),

    (16, 'A', 4,
     "Middle Mediastinum Contents",
     "Middle mediastinum = heart + pericardium. THYMUS is in the ANTERIOR mediastinum.",
     "TRAP: 'aorta' alone or 'trachea' as the main occupant — both wrong.",
     "Anterior = thymus, lymph nodes, fatty tissue. Middle = heart+pericardium, ascending aorta, "
     "SVC, IVC, pulmonary trunk/veins, phrenic nerves. Posterior = descending aorta, esophagus, "
     "thoracic duct, azygos/hemiazygos, sympathetic trunks."),

    (17, 'A', 4,
     "Superior Mediastinum: Recurrent Laryngeal Nerves",
     "RIGHT RLN does NOT descend into superior mediastinum — it hooks at the ROOT OF THE NECK around the right subclavian artery.",
     "TRAP: 'left recurrent laryngeal nerve' not in superior mediastinum — wrong; LEFT RLN IS there.",
     "LEFT RLN hooks under the aortic arch inside the superior mediastinum — vulnerable in aortic arch surgery. "
     "RIGHT RLN hooks around right subclavian at the root of the neck. "
     "Both RLNs supply intrinsic laryngeal muscles (except cricothyroid)."),

    (18, 'H', 4,
     "Pericytes Location",
     "Pericytes are found ONLY in capillaries and postcapillary venules — NOT in all blood vessels.",
     "TRAP: 'pericytes are found in the wall of ALL blood vessels' — FALSE, appeared 4+ times.",
     "Pericytes = long cytoplasmic processes of mesenchymal cells wrapping capillaries/venules. "
     "They regulate capillary diameter, support endothelium, and participate in angiogenesis. "
     "Larger vessels have smooth muscle cells in tunica media instead."),

    (19, 'H', 4,
     "Artery vs Vein: Thickest Layer",
     "ARTERIES: thickest = tunica MEDIA. VEINS: thickest = tunica ADVENTITIA.",
     "TRAP: 'adventitia thickest in arteries' — wrong. Arteries need thick media to handle high pressure.",
     "Arteries: tunica media dominant (smooth muscle + elastic). Veins: tunica adventitia dominant (collagen). "
     "Capillaries = only intima (endothelium + basement membrane). Vasa vasorum = nutrient vessels for large vessel walls."),

    (20, 'A', 4,
     "Tricuspid & Pulmonary Valve Cusps",
     "Tricuspid = ANTERIOR + SEPTAL + POSTERIOR. Pulmonary semilunar = LEFT + RIGHT + ANTERIOR.",
     "TRAP: 'superior, inferior, medial' for tricuspid — wrong. Aortic semilunar = left, right, posterior (non-coronary).",
     "Mitral (bicuspid) = 2 cusps: anterior + posterior. Chordae tendineae prevent AV valve inversion. "
     "Fibrous skeleton prevents overdilation of valve openings. "
     "Aortic valve auscultated at 2nd ICS right. Mitral at apex (5th ICS, left midclavicular)."),

    (21, 'H', 4,
     "Foramen Ovale: Closure Mechanism",
     "Foramen ovale closes when LEFT ATRIAL pressure exceeds RIGHT ATRIAL pressure (at birth).",
     "TRAP: 'closes because ductus arteriosus closes first' — incorrect sequence.",
     "FO allows oxygenated blood (IVC) to bypass RV → go directly LA → LV → body. "
     "At birth: lungs expand → pulmonary resistance drops → LA pressure rises → FO closes. "
     "Probe-patent FO exists in ~25% of adults. Persistent FO = ASD risk."),

    (22, 'P', 4,
     "Frank-Starling Law",
     "Increased venous return → increased EDV → more stretch → stronger contraction → increased SV.",
     "TRAP: 'SV is inversely proportional to EDV' — completely reversed.",
     "Preload = EDV (end-diastolic volume) = myocardial stretch before contraction. "
     "Afterload = aortic pressure for LV. INCORRECT definition of preload: 'right atrial pressure'. "
     "Cardiac tamponade reduces venous return → decreases CO (NOT increases)."),

    (23, 'A', 4,
     "Right Subclavian Artery Origin",
     "Right subclavian arises from the BRACHIOCEPHALIC TRUNK — NOT directly from the aorta.",
     "TRAP: 'right subclavian arises directly from aorta' — FALSE. Left subclavian DOES arise directly.",
     "Aortic arch branches (left → right): brachiocephalic trunk → left CCA → left subclavian. "
     "Brachiocephalic trunk → right CCA + right subclavian. "
     "Subclavian → axillary (at lateral border of 1st rib) → brachial (at lower border of teres major)."),

    (24, 'H', 4,
     "Lymphatic Vessel Lining",
     "Lymphatic vessels are lined by SIMPLE SQUAMOUS epithelium (endothelium).",
     "TRAP: 'stratified squamous epithelium' or 'simple columnar' appeared as wrong answers in multiple versions.",
     "No continuous basement membrane → more permeable than blood capillaries. "
     "Lymph capillaries are absent in CNS, bone marrow, cartilage, cornea. "
     "They are blind-ended and pick up excess interstitial fluid + proteins."),

    (25, 'A', 4,
     "Celiac Trunk Branches",
     "Celiac trunk (T12) = LEFT GASTRIC + SPLENIC + COMMON HEPATIC arteries.",
     "TRAP: 'inferior mesenteric artery' listed as a celiac branch — it is a SEPARATE aortic branch.",
     "Celiac = foregut supply. SMA (L1) = midgut. IMA (L3) = hindgut. "
     "IMA branches: left colic, sigmoid arteries, superior rectal. "
     "Right colic = SMA branch (NOT IMA). Uterine artery = anterior division of internal iliac."),

    (26, 'P', 4,
     "Blood Pressure Regulation",
     "MAP = CO × TPR (cardiac output × total peripheral resistance). Arterioles = main resistance vessels.",
     "TRAP: 'CO = BP ÷ resistance' used as CO formula — wrong direction.",
     "Pulse pressure = SBP − DBP (≈ 40 mmHg). MAP = DBP + PP/3 ≈ 93 mmHg. "
     "Normal BP = 120/80 mmHg. RA pressure ≈ 0 mmHg. RV systolic = 25 mmHg. "
     "Veins = capacitance vessels (64% of blood volume). Precapillary sphincter opens when O₂ is low."),

    (27, 'P', 4,
     "Edema Causes & Lymphatics",
     "Edema = all causes: ↑capillary hydrostatic P + ↓oncotic P + lymphatic obstruction + ↑permeability.",
     "TRAP: 'lymph flow increases when capillary oncotic pressure increases' — wrong; it DECREASES.",
     "Lymph capillaries are absent in CNS. They lack a continuous basement membrane. "
     "Lymph flow DECREASES with ↑capillary oncotic pressure (more fluid reabsorbed back into capillaries). "
     "Lymphatic vessels have valves to prevent backflow. Thoracic duct → left subclavian + left IJV junction."),

    (28, 'P', 4,
     "Peripheral Chemoreceptors Location",
     "Peripheral O₂ chemoreceptors are in the CAROTID BODY and AORTIC BODIES — NOT the carotid sinus.",
     "TRAP: 'carotid sinus and aortic arch' — the carotid SINUS is a BARORECEPTOR, not a chemoreceptor.",
     "Carotid SINUS = baroreceptor (senses pressure). Carotid BODY = chemoreceptor (senses O₂, CO₂, pH). "
     "Central chemoreceptors (brainstem) sense CO₂/pH, NOT O₂. "
     "Severe hyperventilation (↓CO₂) CAN lead to loss of consciousness."),

    (29, 'H', 4,
     "Laryngotracheal Diverticulum",
     "Laryngotracheal diverticulum communicates with the PRIMORDIAL PHARYNX through the laryngeal inlet.",
     "TRAP: 'pharyngeal cavity and primordial cavity' is vague and wrong as used in exam.",
     "Grows from ventral wall of pharynx. Tracheoesophageal septum separates it from esophagus. "
     "Tracheal epithelium = endodermal. Tracheal connective tissue = splanchnic mesenchyme. "
     "Failure of separation → tracheoesophageal fistula → polyhydramnios (amniotic fluid cannot reach stomach)."),

    (30, 'A', 4,
     "Azygos Vein & Thoracic Duct",
     "Azygos vein drains into SVC. Thoracic duct drains into left subclavian + left IJV junction.",
     "TRAP: 'azygos drains into pulmonary veins' or 'thoracic duct drains right side' — both wrong.",
     "Azygos = right side. Hemiazygos = left lower thorax. Accessory hemiazygos = left upper thorax. "
     "Thoracic duct: begins at cisterna chyli (L1-L2), enters thorax at T12, "
     "lies POSTERIOR to ESOPHAGUS in mid-thorax, drains ALL lymph except right upper body."),
]

# ── styles ────────────────────────────────────────────────────────────────────
sCoverH  = S('sCoverH', fontSize=26, textColor=CWH, fontName='Helvetica-Bold',
              alignment=TA_CENTER, leading=30, spaceAfter=4)
sCoverS  = S('sCoverS', fontSize=13, textColor=colors.HexColor('#A0C8EE'),
              fontName='Helvetica', alignment=TA_CENTER, leading=16)
sRankBig = S('sRankBig',fontSize=22, textColor=CWH, fontName='Helvetica-Bold',
              alignment=TA_CENTER, leading=26)
sTopic   = S('sTopic',  fontSize=12, textColor=CWH, fontName='Helvetica-Bold',
              alignment=TA_LEFT,   leading=15, spaceAfter=0)
sApps    = S('sApps',   fontSize=8.5,textColor=CGD2,fontName='Helvetica-Bold',
              alignment=TA_LEFT,   leading=11)
sKeyFact = S('sKeyFact',fontSize=11, textColor=CN,  fontName='Helvetica-Bold',
              leading=14, spaceAfter=2)
sTrap    = S('sTrap',   fontSize=9.5,textColor=CRD, fontName='Helvetica-Bold',
              leading=13, spaceAfter=2)
sDetail  = S('sDetail', fontSize=9,  textColor=colors.HexColor('#333333'),
              fontName='Helvetica', leading=12, spaceAfter=0)
sBoxLbl  = S('sBoxLbl', fontSize=7.5,textColor=CWH, fontName='Helvetica-Bold',
              alignment=TA_CENTER, leading=9)
sSubj    = S('sSubj',   fontSize=8,  textColor=CWH, fontName='Helvetica-Bold',
              alignment=TA_CENTER, leading=10)
sTocN    = S('sTocN',   fontSize=9,  textColor=CN,  fontName='Helvetica-Bold',
              leading=12)
sTocT    = S('sTocT',   fontSize=9,  textColor=CN,  fontName='Helvetica',
              leading=12)
sTocA    = S('sTocA',   fontSize=8,  textColor=CML, fontName='Helvetica',
              leading=11)
sFooter  = S('sFooter', fontSize=7.5,textColor=CML, fontName='Helvetica',
              alignment=TA_CENTER, leading=10)
sSummHdr = S('sSummHdr',fontSize=14, textColor=CWH, fontName='Helvetica-Bold',
              alignment=TA_CENTER, leading=17)

SUBJ_META = {
    'A': (CN,  CSK,  'ANATOMY'),
    'H': (CPU, CLAV, 'HISTO / EMBRYO'),
    'P': (CTL, CTLL, 'PHYSIOLOGY'),
}

# ── helpers ───────────────────────────────────────────────────────────────────
def rank_bg(rank):
    if rank == 1:   return colors.HexColor('#B8860B'), colors.HexColor('#FFF8DC')
    if rank <= 3:   return colors.HexColor('#888888'), colors.HexColor('#F5F5F5')
    if rank <= 10:  return CN,  CSK
    if rank <= 20:  return CPU, CLAV
    return CTL, CTLL

def stars(n):
    full = min(n, 6)
    return '★' * full + '☆' * (6 - full)

def build_card(rank, subj, apps, topic, key_fact, trap, detail):
    hdr_c, bg_c, subj_label = SUBJ_META[subj]
    rk_c, rk_bg = rank_bg(rank)

    # ── header row: [rank badge | apps stars | topic | subj tag] ──────────
    rank_cell = Table(
        [[Paragraph(f'#{rank}', sRankBig)]],
        colWidths=[1.3*cm], rowHeights=[1.4*cm]
    )
    rank_cell.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), rk_c),
        ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
        ('TOPPADDING',(0,0),(-1,-1),0),
        ('BOTTOMPADDING',(0,0),(-1,-1),0),
    ]))

    stars_text  = stars(apps)
    apps_cell = Table(
        [[Paragraph(f'{stars_text}', sApps)],
         [Paragraph(f'seen {apps}×', S(f'sa{rank}', fontSize=7.5, textColor=CML,
                    fontName='Helvetica', alignment=TA_LEFT, leading=9))]],
        colWidths=[1.6*cm]
    )
    apps_cell.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), rk_bg),
        ('TOPPADDING',(0,0),(-1,-1),4),
        ('BOTTOMPADDING',(0,0),(-1,-1),4),
        ('LEFTPADDING',(0,0),(-1,-1),5),
        ('RIGHTPADDING',(0,0),(-1,-1),5),
    ]))

    topic_cell = Table(
        [[Paragraph(topic, sTopic)]],
        colWidths=[W - 1.3*cm - 1.6*cm - 1.8*cm - 0.4*cm]
    )
    topic_cell.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), hdr_c),
        ('TOPPADDING',(0,0),(-1,-1),6),
        ('BOTTOMPADDING',(0,0),(-1,-1),6),
        ('LEFTPADDING',(0,0),(-1,-1),8),
        ('RIGHTPADDING',(0,0),(-1,-1),4),
        ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
    ]))

    subj_cell = Table(
        [[Paragraph(subj_label, sSubj)]],
        colWidths=[1.8*cm]
    )
    subj_cell.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), hdr_c),
        ('TOPPADDING',(0,0),(-1,-1),4),
        ('BOTTOMPADDING',(0,0),(-1,-1),4),
        ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
        ('ALIGN',(0,0),(-1,-1),'CENTER'),
    ]))

    header = Table(
        [[rank_cell, apps_cell, topic_cell, subj_cell]],
        colWidths=[1.3*cm, 1.6*cm, W-1.3*cm-1.6*cm-1.8*cm-0.4*cm, 1.8*cm],
        spaceBefore=0, spaceAfter=0
    )
    header.setStyle(TableStyle([
        ('VALIGN',(0,0),(-1,-1),'TOP'),
        ('LEFTPADDING',(0,0),(-1,-1),0),
        ('RIGHTPADDING',(0,0),(-1,-1),0),
        ('TOPPADDING',(0,0),(-1,-1),0),
        ('BOTTOMPADDING',(0,0),(-1,-1),0),
        ('LINEBELOW',(0,0),(-1,-1),1, hdr_c),
    ]))

    # ── body ──────────────────────────────────────────────────────────────
    kf_label = Table([[Paragraph('KEY FACT', sBoxLbl)]],
                      colWidths=[1.5*cm])
    kf_label.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), CGN),
        ('TOPPADDING',(0,0),(-1,-1),3),('BOTTOMPADDING',(0,0),(-1,-1),3),
        ('LEFTPADDING',(0,0),(-1,-1),3),('RIGHTPADDING',(0,0),(-1,-1),3),
        ('ROUNDEDCORNERS',(0,0),(-1,-1),[4,4,4,4]),
    ]))
    kf_text = Table([[Paragraph(key_fact, sKeyFact)]], colWidths=[W - 1.5*cm - 0.3*cm])
    kf_text.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), CLM),
        ('TOPPADDING',(0,0),(-1,-1),5),('BOTTOMPADDING',(0,0),(-1,-1),5),
        ('LEFTPADDING',(0,0),(-1,-1),8),('RIGHTPADDING',(0,0),(-1,-1),8),
    ]))
    kf_row = Table([[kf_label, Spacer(0.3*cm,1), kf_text]],
                    colWidths=[1.5*cm, 0.3*cm, W-1.5*cm-0.3*cm])
    kf_row.setStyle(TableStyle([
        ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
        ('LEFTPADDING',(0,0),(-1,-1),0),('RIGHTPADDING',(0,0),(-1,-1),0),
        ('TOPPADDING',(0,0),(-1,-1),0),('BOTTOMPADDING',(0,0),(-1,-1),0),
    ]))

    tr_label = Table([[Paragraph('⚠ TRAP', sBoxLbl)]],
                      colWidths=[1.5*cm])
    tr_label.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), CRD),
        ('TOPPADDING',(0,0),(-1,-1),3),('BOTTOMPADDING',(0,0),(-1,-1),3),
        ('LEFTPADDING',(0,0),(-1,-1),3),('RIGHTPADDING',(0,0),(-1,-1),3),
        ('ROUNDEDCORNERS',(0,0),(-1,-1),[4,4,4,4]),
    ]))
    tr_text = Table([[Paragraph(trap, sTrap)]], colWidths=[W - 1.5*cm - 0.3*cm])
    tr_text.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), CPK),
        ('TOPPADDING',(0,0),(-1,-1),5),('BOTTOMPADDING',(0,0),(-1,-1),5),
        ('LEFTPADDING',(0,0),(-1,-1),8),('RIGHTPADDING',(0,0),(-1,-1),8),
    ]))
    tr_row = Table([[tr_label, Spacer(0.3*cm,1), tr_text]],
                    colWidths=[1.5*cm, 0.3*cm, W-1.5*cm-0.3*cm])
    tr_row.setStyle(TableStyle([
        ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
        ('LEFTPADDING',(0,0),(-1,-1),0),('RIGHTPADDING',(0,0),(-1,-1),0),
        ('TOPPADDING',(0,0),(-1,-1),0),('BOTTOMPADDING',(0,0),(-1,-1),0),
    ]))

    det_label = Table([[Paragraph('DETAIL', sBoxLbl)]],
                       colWidths=[1.5*cm])
    det_label.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), CB),
        ('TOPPADDING',(0,0),(-1,-1),3),('BOTTOMPADDING',(0,0),(-1,-1),3),
        ('LEFTPADDING',(0,0),(-1,-1),3),('RIGHTPADDING',(0,0),(-1,-1),3),
        ('ROUNDEDCORNERS',(0,0),(-1,-1),[4,4,4,4]),
    ]))
    det_text = Table([[Paragraph(detail, sDetail)]], colWidths=[W - 1.5*cm - 0.3*cm])
    det_text.setStyle(TableStyle([
        ('BACKGROUND',(0,0),(-1,-1), CGY),
        ('TOPPADDING',(0,0),(-1,-1),5),('BOTTOMPADDING',(0,0),(-1,-1),5),
        ('LEFTPADDING',(0,0),(-1,-1),8),('RIGHTPADDING',(0,0),(-1,-1),8),
    ]))
    det_row = Table([[det_label, Spacer(0.3*cm,1), det_text]],
                     colWidths=[1.5*cm, 0.3*cm, W-1.5*cm-0.3*cm])
    det_row.setStyle(TableStyle([
        ('VALIGN',(0,0),(-1,-1),'TOP'),
        ('LEFTPADDING',(0,0),(-1,-1),0),('RIGHTPADDING',(0,0),(-1,-1),0),
        ('TOPPADDING',(0,0),(-1,-1),0),('BOTTOMPADDING',(0,0),(-1,-1),0),
    ]))

    body_rows = [[kf_row],[Spacer(1,4)],[tr_row],[Spacer(1,4)],[det_row]]
    body = Table(body_rows, colWidths=[W])
    body.setStyle(TableStyle([
        ('TOPPADDING',(0,0),(-1,-1),5),
        ('BOTTOMPADDING',(0,0),(-1,-1),5),
        ('LEFTPADDING',(0,0),(-1,-1),8),
        ('RIGHTPADDING',(0,0),(-1,-1),8),
        ('BACKGROUND',(0,0),(-1,-1), CWH),
    ]))

    # ── assemble ──────────────────────────────────────────────────────────
    card = Table([[header],[body]], colWidths=[W])
    card.setStyle(TableStyle([
        ('BOX',(0,0),(-1,-1),1.5, hdr_c),
        ('TOPPADDING',(0,0),(-1,-1),0),
        ('BOTTOMPADDING',(0,0),(-1,-1),0),
        ('LEFTPADDING',(0,0),(-1,-1),0),
        ('RIGHTPADDING',(0,0),(-1,-1),0),
    ]))
    return card

# ── BUILD DOC ─────────────────────────────────────────────────────────────────
doc = SimpleDocTemplate(
    OUTPUT, pagesize=A4,
    leftMargin=M, rightMargin=M, topMargin=M, bottomMargin=M,
    title='Top 30 Most Tested Topics — Last Minute Review',
    author='Orris AI'
)
story = []

# ── COVER ─────────────────────────────────────────────────────────────────────
cover = Table([
    [Paragraph('🏆  TOP 30', sCoverH)],
    [Paragraph('Most Frequently Tested Topics', sCoverS)],
    [Paragraph('Human Body Systems — Finals Last-Minute Review', sCoverS)],
    [Spacer(1, 0.4*cm)],
    [Paragraph('Anatomy  •  Histology & Embryology  •  Physiology', sCoverS)],
    [Spacer(1, 0.4*cm)],
    [Table([[
        Paragraph('Ranked by frequency across all 5 exam versions.\n'
                  'Each topic shows: ✅ KEY FACT to memorise  •  ⚠ TRAP answer to avoid  •  📌 Supporting detail.',
                  S('ci', fontSize=10, textColor=colors.HexColor('#AACCEE'),
                    fontName='Helvetica', alignment=TA_CENTER, leading=14))
    ]], colWidths=[W-2*cm])],
    [Spacer(1, 0.3*cm)],
    [Table([[
        Paragraph('🟦 Blue = Anatomy', S('la', fontSize=10, textColor=colors.HexColor('#60A8FF'),
                  fontName='Helvetica-Bold', alignment=TA_CENTER)),
        Paragraph('🟪 Purple = Histo/Embryo', S('lh', fontSize=10, textColor=colors.HexColor('#CC88FF'),
                  fontName='Helvetica-Bold', alignment=TA_CENTER)),
        Paragraph('🟩 Teal = Physiology', S('lp', fontSize=10, textColor=colors.HexColor('#44DDCC'),
                  fontName='Helvetica-Bold', alignment=TA_CENTER)),
    ]], colWidths=[W/3]*3)],
], colWidths=[W])
cover.setStyle(TableStyle([
    ('BACKGROUND',(0,0),(-1,-1), CN),
    ('TOPPADDING',(0,0),(-1,-1),10),
    ('BOTTOMPADDING',(0,0),(-1,-1),10),
    ('LEFTPADDING',(0,0),(-1,-1),20),
    ('RIGHTPADDING',(0,0),(-1,-1),20),
    ('LINEBELOW',(0,2),(0,2),1,CB),
    ('LINEBELOW',(0,4),(0,4),0.5, colors.HexColor('#2244AA')),
    ('ROUNDEDCORNERS',(0,0),(-1,-1),[8,8,8,8]),
]))
story.append(cover)
story.append(Spacer(1, 0.4*cm))

# ── QUICK INDEX TABLE ─────────────────────────────────────────────────────────
idx_hdr = Table([[Paragraph('QUICK INDEX', S('ih', fontSize=11, textColor=CWH,
    fontName='Helvetica-Bold', alignment=TA_CENTER, leading=14))]],
    colWidths=[W])
idx_hdr.setStyle(TableStyle([
    ('BACKGROUND',(0,0),(-1,-1), colors.HexColor('#2244AA')),
    ('TOPPADDING',(0,0),(-1,-1),5),('BOTTOMPADDING',(0,0),(-1,-1),5),
]))
story.append(idx_hdr)

# 3-column index
idx_rows = []
for i in range(0, 30, 3):
    row = []
    for j in range(3):
        if i+j < 30:
            r, subj, apps, topic = TOP30[i+j][:4]
            hdr_c = SUBJ_META[subj][0]
            row.append(Paragraph(
                f'<font color="#{hdr_c.hexval()[2:]}"><b>#{r}</b></font>  {topic}',
                S(f'idx{r}', fontSize=8.5, textColor=CN, fontName='Helvetica', leading=11)
            ))
        else:
            row.append(Paragraph('', S(f'e{i+j}', fontSize=8)))
    idx_rows.append(row)

idx_tab = Table(idx_rows, colWidths=[W/3]*3)
idx_tab.setStyle(TableStyle([
    ('INNERGRID',(0,0),(-1,-1),0.3,CLT),
    ('BOX',(0,0),(-1,-1),0.5,CB),
    ('TOPPADDING',(0,0),(-1,-1),3),
    ('BOTTOMPADDING',(0,0),(-1,-1),3),
    ('LEFTPADDING',(0,0),(-1,-1),6),
    ('RIGHTPADDING',(0,0),(-1,-1),4),
    ('BACKGROUND',(0,0),(-1,-1),CGY),
    *[('BACKGROUND',(0,r),(2,r),CWH if r%2==0 else CGY) for r in range(len(idx_rows))]
]))
story.append(idx_tab)
story.append(PageBreak())

# ── TOPIC CARDS ───────────────────────────────────────────────────────────────
for entry in TOP30:
    rank, subj, apps, topic, key_fact, trap, detail = entry
    card = build_card(rank, subj, apps, topic, key_fact, trap, detail)
    story.append(KeepTogether([card, Spacer(1, 0.5*cm)]))

# ── FINAL SUMMARY PAGE ────────────────────────────────────────────────────────
story.append(PageBreak())

summ_hdr = Table([[Paragraph('⚡  THE MOST COMMON TRAPS — NEVER GET THESE WRONG', sSummHdr)]],
                  colWidths=[W])
summ_hdr.setStyle(TableStyle([
    ('BACKGROUND',(0,0),(-1,-1),CRD),
    ('TOPPADDING',(0,0),(-1,-1),8),
    ('BOTTOMPADDING',(0,0),(-1,-1),8),
    ('ROUNDEDCORNERS',(0,0),(-1,-1),[6,6,0,0]),
]))
story.append(summ_hdr)
story.append(Spacer(1,0.15*cm))

traps = [
    ("Surfactant DECREASES (not increases) surface tension",
     "appeared WRONG in 4+ exam versions as 'increases'"),
    ("Ciliated pseudostratified columnar epithelium is NOT in bronchioles",
     "FALSE statement repeated 4× and students still answered True"),
    ("Heart chambers partition in WEEKS 5-8, not week 4",
     "'4th week' was the wrong answer most students selected"),
    ("Collateral flow PROTECTS — does NOT damage — the myocardium",
     "'damages' appeared as an option and was chosen incorrectly 4+ times"),
    ("Anterior cardiac veins → RIGHT ATRIUM, not coronary sinus",
     "students confused with great cardiac vein"),
    ("Ductus venosus → Ligamentum VENOSUM (not arteriosum)",
     "ductus arteriosus → ligamentum arteriosum — students mixed these up"),
    ("Right subclavian arises from BRACHIOCEPHALIC TRUNK, not aorta",
     "answered wrong as 'from aorta directly' multiple times"),
    ("Pericytes are in capillaries/venules ONLY, not all vessels",
     "'all blood vessels' was chosen incorrectly 4+ times"),
    ("Peripheral chemoreceptors = carotid BODY (not carotid sinus)",
     "carotid sinus = baroreceptor, appeared confusingly similar"),
    ("Vagal stimulation does NOT increase Ca²⁺ influx — it increases K⁺ permeability",
     "'increases Ca²⁺' was the trap answer for ACh effect"),
    ("Cardiac tamponade DECREASES cardiac output (not increases)",
     "'increases CO' was a chosen wrong answer"),
    ("LEFT bronchus is longer, narrower, more horizontal (not wider/vertical)",
     "reversed descriptions appeared and were selected"),
    ("IMA branches: left colic, sigmoid, superior rectal — RIGHT colic = SMA",
     "right colic was listed as IMA branch in wrong answers"),
    ("IVRT: ALL valves closed (both mitral AND aortic)",
     "'mitral open, aortic closed' was a common wrong answer"),
    ("Lymph flow DECREASES when capillary oncotic pressure INCREASES",
     "students answered 'increased lymph flow' incorrectly"),
]

trap_rows = []
for i, (trap_text, why) in enumerate(traps):
    bg = CPK if i % 2 == 0 else CWH
    trap_rows.append([
        Paragraph(f'<b>{i+1}.</b>  {trap_text}',
                  S(f'tr{i}', fontSize=9.5, textColor=CRD, fontName='Helvetica-Bold', leading=13)),
        Paragraph(f'({why})',
                  S(f'tw{i}', fontSize=8.5, textColor=CML, fontName='Helvetica-Oblique', leading=11)),
    ])

trap_tab = Table(trap_rows, colWidths=[W*0.55, W*0.45])
trap_style = [
    ('BOX',(0,0),(-1,-1),0.8,CRD),
    ('INNERGRID',(0,0),(-1,-1),0.3,CLT),
    ('TOPPADDING',(0,0),(-1,-1),5),
    ('BOTTOMPADDING',(0,0),(-1,-1),5),
    ('LEFTPADDING',(0,0),(-1,-1),8),
    ('RIGHTPADDING',(0,0),(-1,-1),8),
    ('VALIGN',(0,0),(-1,-1),'MIDDLE'),
]
for i in range(len(trap_rows)):
    bg = CPK if i % 2 == 0 else CWH
    trap_style.append(('BACKGROUND',(0,i),(-1,i), bg))
trap_tab.setStyle(TableStyle(trap_style))
story.append(trap_tab)

story.append(Spacer(1, 0.4*cm))

# ── numbers to remember ───────────────────────────────────────────────────────
num_hdr = Table([[Paragraph('🔢  NUMBERS TO REMEMBER', S('nh', fontSize=11, textColor=CWH,
    fontName='Helvetica-Bold', alignment=TA_CENTER, leading=14))]], colWidths=[W])
num_hdr.setStyle(TableStyle([
    ('BACKGROUND',(0,0),(-1,-1), CN),
    ('TOPPADDING',(0,0),(-1,-1),5),('BOTTOMPADDING',(0,0),(-1,-1),5),
    ('ROUNDEDCORNERS',(0,0),(-1,-1),[6,6,0,0]),
]))
story.append(num_hdr)

nums = [
    ['Normal BP', '120/80 mmHg',       'Right atrial pressure', '~0 mmHg'],
    ['RV systolic', '25 mmHg',          'LV systolic', '120 mmHg'],
    ['Trachea', 'C6 → T4',             'Bifurcation', 'T4/T5'],
    ['Right lung lobes', '3',           'Left lung lobes', '2'],
    ['CO normal', '~5 L/min',          'EF normal', '55-70%'],
    ['Lung base (midaxillary)', 'Rib VIII', 'Pleural reflection', 'Rib X'],
    ['Thoracic duct starts', 'L1-L2 (cisterna chyli)', 'Ends', 'Left subclavian + IJV'],
    ['Surfactant starts', '~20-22 wk',  'Heart beats start', 'Day 21 (wk 3)'],
    ['PR interval normal', '0.12-0.20s', 'Veins hold blood', '~64% of total volume'],
    ['IMA originates', 'L3',            'Celiac trunk', 'T12'],
]

num_rows = []
for row in nums:
    num_rows.append([
        Paragraph(f'<b>{row[0]}</b>', S('nl', fontSize=9, textColor=CN, fontName='Helvetica-Bold', leading=12)),
        Paragraph(f'<b>{row[1]}</b>', S('nv', fontSize=9, textColor=CGN, fontName='Helvetica-Bold', leading=12)),
        Paragraph(f'<b>{row[2]}</b>', S('nl2', fontSize=9, textColor=CN, fontName='Helvetica-Bold', leading=12)),
        Paragraph(f'<b>{row[3]}</b>', S('nv2', fontSize=9, textColor=CGN, fontName='Helvetica-Bold', leading=12)),
    ])

num_tab = Table(num_rows, colWidths=[W*0.22, W*0.28, W*0.22, W*0.28])
num_style = [
    ('BOX',(0,0),(-1,-1),0.8, CN),
    ('INNERGRID',(0,0),(-1,-1),0.3, CLT),
    ('TOPPADDING',(0,0),(-1,-1),4),
    ('BOTTOMPADDING',(0,0),(-1,-1),4),
    ('LEFTPADDING',(0,0),(-1,-1),6),
    ('RIGHTPADDING',(0,0),(-1,-1),6),
]
for i in range(len(num_rows)):
    bg = CSK if i % 2 == 0 else CWH
    num_style.append(('BACKGROUND',(0,i),(-1,i), bg))
num_tab.setStyle(TableStyle(num_style))
story.append(num_tab)

doc.build(story)
print(f'Done → {OUTPUT}')