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

styles = getSampleStyleSheet()
normal = ParagraphStyle('normal', parent=styles['Normal'], fontSize=10.5, leading=13)
bold = ParagraphStyle('bold', parent=normal, fontName='Helvetica-Bold')
center = ParagraphStyle('center', parent=normal, alignment=TA_CENTER)
center_bold = ParagraphStyle('center_bold', parent=bold, alignment=TA_CENTER)
italic_small = ParagraphStyle('italic_small', parent=normal, fontName='Helvetica-Oblique', fontSize=9.5)
subpart = ParagraphStyle('subpart', parent=normal, leftIndent=6)

doc = SimpleDocTemplate(
    "/tmp/workspace/ouhs-anatomy-paper1/output/OUHS_Anatomy_Paper1_Predicted.pdf",
    pagesize=A4,
    topMargin=1.4*cm, bottomMargin=1.4*cm, leftMargin=1.6*cm, rightMargin=1.6*cm
)

elements = []

# ---------- Registration number row ----------
reg_boxes = Table([[""]*8], colWidths=[1.6*cm]*8, rowHeights=0.7*cm)
reg_boxes.setStyle(TableStyle([
    ('BOX', (0,0), (-1,-1), 0.8, colors.black),
    ('INNERGRID', (0,0), (-1,-1), 0.8, colors.black),
]))
reg_row = Table([[Paragraph("Registration no:", bold), reg_boxes]],
                colWidths=[4.2*cm, 12.8*cm])
reg_row.setStyle(TableStyle([
    ('VALIGN', (0,0), (-1,-1), 'MIDDLE'),
]))
elements.append(reg_row)
elements.append(Spacer(1, 6))

# ---------- Header info block ----------
header_data = [
    [Paragraph("Total Number of Pages: 04", bold), Paragraph("Course: MBBS", bold)],
    ["", Paragraph("SUB_CODE: 525051", bold)],
]
header_tbl = Table(header_data, colWidths=[10.5*cm, 6.5*cm])
header_tbl.setStyle(TableStyle([
    ('BOX', (0,0), (-1,-1), 0.8, colors.black),
    ('LINEBELOW', (0,0), (-1,0), 0.5, colors.black),
    ('VALIGN', (0,0), (-1,-1), 'MIDDLE'),
]))

exam_line = Paragraph(
    "( <u>&nbsp;X&nbsp;</u> Professional Regular / Supplementary / Attempt / Detained Examination: 2026 - August)",
    normal
)

info_rows = [
    [exam_line],
    [Paragraph("SUBJECT NAME: <b>HUMAN ANATOMY</b>", normal)],
    [Paragraph("BRANCH: MBBS &ndash; Phase I", normal)],
    [Table([[Paragraph("Max Time: 3 Hours", normal), Paragraph("Sitting: 1st 10.00 AM to 1.00 PM", normal)]],
           colWidths=[8.5*cm, 8.5*cm], style=TableStyle([('LEFTPADDING',(0,0),(-1,-1),0),('TOPPADDING',(0,0),(-1,-1),0),('BOTTOMPADDING',(0,0),(-1,-1),0)]))],
    [Paragraph("Max Marks: 100", normal)],
    [Paragraph("Q. CODE: <i>(To be allotted by the University)</i>", normal)],
]

info_tbl = Table(info_rows, colWidths=[17*cm])
info_tbl.setStyle(TableStyle([
    ('BOX', (0,0), (-1,-1), 0.8, colors.black),
    ('LINEBELOW', (0,0), (-2,-1), 0.4, colors.black),
    ('TOPPADDING', (0,0), (-1,-1), 3),
    ('BOTTOMPADDING', (0,0), (-1,-1), 3),
    ('LEFTPADDING', (0,0), (-1,-1), 6),
]))

full_header = Table([[header_tbl]], colWidths=[17*cm])
full_header.setStyle(TableStyle([('BOX',(0,0),(-1,-1),0.8,colors.black)]))

elements.append(full_header)
elements.append(info_tbl)

instr_data = [
    [Paragraph("All Questions are compulsory. Illustrate answer with diagrams wherever relevant / required", center)],
    [Paragraph("The figures in the right-hand margin indicate marks", center)],
    [Paragraph("This paper covers: General Anatomy, General &amp; Systematic Embryology, Head, Neck &amp; Face, "
               "Neuroanatomy, and Thorax", center)],
]
instr_tbl = Table(instr_data, colWidths=[17*cm])
instr_tbl.setStyle(TableStyle([
    ('BOX', (0,0), (-1,-1), 0.8, colors.black),
    ('LINEBELOW', (0,0), (-1,-2), 0.4, colors.black),
    ('TOPPADDING', (0,0), (-1,-1), 3),
    ('BOTTOMPADDING', (0,0), (-1,-1), 3),
]))
elements.append(instr_tbl)
elements.append(Spacer(1, 8))

# ---------- helper to build a question block table ----------
def q_row(qno, label, marks, rowspan_label=True):
    return [Paragraph(qno, bold), Paragraph(label, normal), Paragraph(marks, bold)]

def sub_row(letter, text, marks=""):
    return [ "", Paragraph(f"{letter}) {text}", subpart), Paragraph(marks, normal)]

def build_qtable(rows, col_widths=(1.6*cm, 12.9*cm, 2.5*cm)):
    t = Table(rows, colWidths=list(col_widths))
    style = [
        ('BOX', (0,0), (-1,-1), 0.8, colors.black),
        ('INNERGRID', (0,0), (-1,-1), 0.4, colors.black),
        ('VALIGN', (0,0), (-1,-1), 'TOP'),
        ('TOPPADDING', (0,0), (-1,-1), 4),
        ('BOTTOMPADDING', (0,0), (-1,-1), 4),
        ('LEFTPADDING', (0,0), (-1,-1), 5),
        ('ALIGN', (2,0), (2,-1), 'CENTER'),
    ]
    t.setStyle(TableStyle(style))
    return t

# ===================== Q1 =====================
q1_rows = [q_row("Q 1", "<b>Scenario Based MCQ</b>", "(10 x 2 = 20 Marks)")]
mcqs = [
 "A 45-year-old man undergoes parotidectomy for a pleomorphic adenoma. Post-operatively he develops "
 "asymmetry of the face with inability to close the right eye and drooping of the angle of mouth. "
 "Injury to which structure best explains this presentation, and through which part of the parotid "
 "gland does it pass?",
 "A newborn presents with a midline swelling in the neck that moves upward on protrusion of the tongue. "
 "Name the embryological structure responsible and the arch/pouch derivative involved in its descent.",
 "A cyclist falls on an outstretched hand and sustains a fracture of the scaphoid. Which artery is most "
 "at risk, and what complication may follow due to its pattern of blood supply?",
 "A patient presents with claw hand deformity and loss of sensation over the medial one and a half "
 "fingers following a stab injury at the wrist. Which nerve is injured and which muscles are spared?",
 "A young man involved in a road traffic accident presents with a 'winged scapula' on attempting to push "
 "against a wall. Which nerve and muscle are implicated, and from which roots does the nerve arise?",
 "During a difficult forceps delivery, a neonate shows the arm adducted and medially rotated, forearm "
 "pronated and extended, the 'waiter's tip' posture. Which roots of the brachial plexus are involved?",
 "A patient with a stab wound in the 5th intercostal space just lateral to the sternum on the left develops "
 "muffled heart sounds, distended neck veins and hypotension. Which anatomical space has been breached?",
 "A trauma patient requires an emergency tube thoracostomy. Name the anatomical landmark ('triangle of "
 "safety') and the structure at risk if the incision is placed too low.",
 "A 6-week-old infant presents with projectile vomiting and a palpable olive-sized mass; workup reveals "
 "hypertrophic pyloric stenosis. From which part of the primitive gut and its rotation does this anomaly arise? (Applied embryology cross-link)",
 "A patient develops sudden contralateral hemiplegia with sparing of the face after a lacunar infarct. "
 "Occlusion of which branch of which major cerebral artery best explains this, and which internal capsule "
 "region is affected?",
]
for i, m in enumerate(mcqs):
    letter = chr(ord('a')+i)
    q1_rows.append(sub_row(letter, m, ""))
elements.append(build_qtable(q1_rows))
elements.append(Spacer(1, 10))

# ===================== Q2 =====================
q2_rows = [q_row("Q 2", "<b>Long Answer Question</b>", "(1 x 10 Marks)")]
q2_rows.append(sub_row("", "Describe the Brachial Plexus under the following headings: Formation and roots "
                            "(2), Trunks, divisions and cords with relation to the axillary artery (2), Branches "
                            "arising from the plexus (3), Applied anatomy of Erb's palsy and Klumpke's palsy (3).", "(2+2+3+3)"))
elements.append(build_qtable(q2_rows))
elements.append(Spacer(1, 10))

# ===================== Q3 =====================
q3_rows = [q_row("Q 3", "<b>Reasoning Questions</b> &ndash; Give reasons for the following:", "(5 x 3 = 15 Marks)")]
reasons = [
 "Sensations from the lateral three and a half fingers are lost in carpal tunnel syndrome but sensation "
 "over the thenar eminence is retained.",
 "Hoarseness of voice is a recognised complication of thyroidectomy.",
 "A fracture of the surgical neck of the humerus can result in wrist drop.",
 "Congenital diaphragmatic hernia most commonly occurs through the left posterolateral defect (foramen of Bochdalek).",
 "Infection of the 'danger area' of the scalp can spread intracranially to cause cavernous sinus thrombosis.",
]
for i, r in enumerate(reasons):
    letter = chr(ord('a')+i)
    q3_rows.append(sub_row(letter, r, "3"))
elements.append(build_qtable(q3_rows))
elements.append(Spacer(1, 10))

# ===================== Q4 =====================
q4_rows = [q_row("Q 4", "<b>Short Notes (Applied Aspects)</b>", "(4 x 5 = 20 Marks)")]
q4_items = [
 "Applied anatomy of the cubital fossa (venepuncture, supracondylar fracture).",
 "Applied anatomy of the pleura and pleural recesses (thoracocentesis, pneumothorax).",
 "Applied anatomy of the cavernous sinus (cavernous sinus thrombosis, III, IV, VI nerve palsy).",
 "Applied anatomy of the axilla (axillary lymph node clearance in breast carcinoma).",
]
for i, t in enumerate(q4_items):
    letter = chr(ord('a')+i)
    q4_rows.append(sub_row(letter, t, "5"))
elements.append(build_qtable(q4_rows))
elements.append(Spacer(1, 10))

# ===================== Q5 =====================
q5_rows = [q_row("Q 5", "<b>Short Notes</b>", "(3 x 5 = 15 Marks)")]
q5_items = [
 "Development of the interatrial septum and its clinical correlation with atrial septal defects.",
 "Circle of Willis &ndash; formation, branches and clinical significance.",
 "Thymus gland &ndash; development, gross anatomy and applied anatomy.",
]
for i, t in enumerate(q5_items):
    letter = chr(ord('a')+i)
    q5_rows.append(sub_row(letter, t, "5"))
elements.append(build_qtable(q5_rows))
elements.append(Spacer(1, 10))

# ===================== Q6 =====================
q6_rows = [q_row("Q 6", "<b>Short Notes</b> (5 marks from AETCOM to be included)", "(4 x 5 = 20 Marks)")]
q6_items = [
 "Dermatomes of the upper limb and their clinical importance in localising nerve root lesions.",
 "Development of the face and pharyngeal (branchial) arches; embryological basis of cleft lip.",
 "Median cubital vein &ndash; anatomy, surface marking and clinical importance.",
 "AETCOM: As the treating doctor, describe how you would empathetically communicate the diagnosis and "
 "prognosis of a permanent lower motor neuron facial nerve palsy (Bell's palsy) to an anxious patient, "
 "highlighting principles of breaking bad news and informed communication.",
]
for i, t in enumerate(q6_items):
    letter = chr(ord('a')+i)
    q6_rows.append(sub_row(letter, t, "5"))
elements.append(build_qtable(q6_rows))
elements.append(Spacer(1, 14))

elements.append(Paragraph("*" * 40, center))

doc.build(elements)
print("PDF generated.")

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

styles = getSampleStyleSheet()
title_style = ParagraphStyle('title', parent=styles['Title'], fontSize=18, spaceAfter=4)
sub_title = ParagraphStyle('sub', parent=styles['Normal'], fontSize=11, alignment=TA_CENTER,
                            textColor=colors.HexColor('#444444'), spaceAfter=14)
h1 = ParagraphStyle('h1', parent=styles['Heading1'], fontSize=14, textColor=colors.HexColor('#1a3d6d'),
                     spaceBefore=14, spaceAfter=6)
h2 = ParagraphStyle('h2', parent=styles['Heading2'], fontSize=11.5, textColor=colors.HexColor('#8a1c1c'),
                     spaceBefore=8, spaceAfter=3)
body = ParagraphStyle('body', parent=styles['Normal'], fontSize=9.7, leading=12.5)
bullet_style = ParagraphStyle('bullet', parent=body, leftIndent=10, spaceAfter=2)

doc = SimpleDocTemplate(
    "/tmp/workspace/ouhs-anatomy-paper1/output/OUHS_Anatomy_Paper1_StudyGuide.pdf",
    pagesize=A4, topMargin=1.3*cm, bottomMargin=1.3*cm, leftMargin=1.6*cm, rightMargin=1.6*cm
)

elements = []
elements.append(Paragraph("OUHS MBBS Anatomy - Paper 1", title_style))
elements.append(Paragraph("High-Yield Study Guide: General Anatomy, General & Systematic Embryology, "
                           "Head-Neck-Face, Neuroanatomy, Upper Limb, Thorax", sub_title))

def add_section(heading, subsections):
    elements.append(Paragraph(heading, h1))
    for sub_h, points in subsections:
        if sub_h:
            elements.append(Paragraph(sub_h, h2))
        items = [ListItem(Paragraph(p, bullet_style), leftIndent=12, bulletFontSize=8) for p in points]
        elements.append(ListFlowable(items, bulletType='bullet', start='circle', bulletFontSize=6,
                                      leftIndent=14, spaceAfter=4))

# 1. General Anatomy
add_section("1. General Anatomy", [
    ("Terminology & Planes", [
        "Anatomical position; sagittal, coronal (frontal) and transverse (axial) planes; terms of relation (superior/inferior, medial/lateral, proximal/distal) and movement.",
    ]),
    ("Joints", [
        "Classification: fibrous (suture, syndesmosis, gomphosis), cartilaginous (primary - synchondrosis; secondary - symphysis), synovial.",
        "Synovial joint types by shape: hinge, pivot, saddle, condylar, ball-and-socket, plane - with one example of each (high-yield MCQ area).",
    ]),
    ("Fascia", [
        "Superficial fascia: fatty layer (Camper's) and membranous layer (Scarpa's) - clinical relevance in perineal/abdominal wall infections.",
        "Deep fascia - investing layer, forms retinacula and compartments; clinical correlation with compartment syndrome.",
    ]),
    ("Muscle & Skin", [
        "Types of muscle (skeletal, smooth, cardiac) and naming conventions (action, shape, location, attachments).",
        "Skin layers - epidermis (5 layers, mnemonic 'Come Let's Get Sun Burnt') and dermis (papillary, reticular); appendages.",
    ]),
    ("Vessels, Nerves & Lymphatics", [
        "Artery vs vein histology; end arteries vs anastomotic arteries and clinical significance (e.g. retina, coronary vessels).",
        "Structure of a peripheral nerve (endoneurium, perineurium, epineurium) and classification of nerve fibres (A, B, C).",
        "Basic lymph node structure and lymphatic drainage principles - often tested via applied questions on regional nodes.",
    ]),
])

# 2. General Embryology
add_section("2. General Embryology", [
    ("Gametogenesis & Fertilization", [
        "Spermatogenesis and oogenesis - key differences and timing (oogenesis arrest at MII until fertilization).",
        "Fertilization occurs in the ampulla of the uterine tube; capacitation and acrosome reaction are prerequisites.",
    ]),
    ("Early Development", [
        "Cleavage -> morula -> blastocyst; implantation typically day 6-7, usually in the posterior superior wall of the uterus.",
        "Bilaminar disc (epiblast/hypoblast) -> gastrulation via the primitive streak forms the trilaminar disc (ectoderm, mesoderm, endoderm).",
        "Notochord formation - induces neural plate; defines the future vertebral axis.",
    ]),
    ("Neurulation & Folding", [
        "Neural tube formation; cranial and caudal neuropore closure (day 25 and 27) - failure causes anencephaly/spina bifida.",
        "Neural crest cell derivatives - a favourite high-yield list (melanocytes, adrenal medulla, cranial ganglia, facial cartilage, etc.).",
        "Cephalocaudal and lateral folding of the embryo - establishes body cavity and gut tube.",
    ]),
    ("Placenta, Membranes & Teratology", [
        "Placenta - development, layers (syncytiotrophoblast/cytotrophoblast), functions, and basic types.",
        "Fetal membranes: amnion, chorion, yolk sac, allantois - and their fate/clinical remnants (Meckel's diverticulum from yolk stalk).",
        "Monozygotic vs dizygotic twinning and timing-dependent placental/amniotic configurations.",
        "Teratogen concept - critical period of vulnerability (weeks 3-8 for major organs).",
    ]),
])

# 3. Head and Neck
add_section("3. Head and Neck", [
    ("Skull & Cranial Fossae", [
        "Norma views, major sutures and fontanelles (anterior fontanelle closes ~18 months).",
        "Anterior, middle and posterior cranial fossae - boundaries and structures traversing each foramen (foramen ovale, rotundum, spinosum, jugular foramen, internal acoustic meatus) - classic reasoning/MCQ topic.",
    ]),
    ("Neck Regions", [
        "Triangles of the neck (anterior and posterior, with subdivisions) and their contents.",
        "Deep cervical fascia - layers (investing, pretracheal, prevertebral) and fascial spaces (retropharyngeal space, danger space) - route of infection spread into the mediastinum.",
    ]),
    ("Glands", [
        "Parotid gland - relations, facial nerve branches traversing it, parotid duct opening (upper second molar).",
        "Submandibular gland - superficial/deep parts, relation to lingual and hypoglossal nerves, Wharton's duct.",
        "Thyroid gland - relations, blood supply (superior/inferior thyroid arteries), close relation of recurrent laryngeal nerve to inferior thyroid artery (surgical importance).",
        "Parathyroid glands - number, location, embryological origin (superior from 4th pouch, inferior from 3rd pouch).",
    ]),
    ("Larynx & Pharynx", [
        "Laryngeal cartilages, muscles and nerve supply (recurrent laryngeal - all intrinsic muscles except cricothyroid; external laryngeal - cricothyroid).",
        "Pharynx subdivisions (naso-, oro-, laryngopharynx), Waldeyer's ring, muscles of deglutition.",
    ]),
])

# 4. Face
add_section("4. Face", [
    ("Facial Nerve", [
        "Course: nuclear origin, intracranial, intratemporal (through facial canal, geniculate ganglion, chorda tympani given off), and extracranial course through parotid gland.",
        "Terminal branches (mnemonic 'Two Zulu Ministers Broke Camp' = Temporal, Zygomatic, Buccal, Marginal mandibular, Cervical).",
        "UMN vs LMN facial palsy - forehead sparing distinguishes UMN (stroke) from LMN (Bell's palsy) lesions - classic reasoning question.",
    ]),
    ("Vessels & Sensory Supply", [
        "Facial artery course and branches; 'danger area of the face' (nose to angle of mouth) drains via facial vein -> ophthalmic veins -> cavernous sinus (route for intracranial spread of infection).",
        "Trigeminal nerve - three divisions (ophthalmic, maxillary, mandibular) providing sensory supply to the face.",
    ]),
    ("Scalp", [
        "Layers - mnemonic SCALP (Skin, Connective tissue, Aponeurosis, Loose areolar tissue, Pericranium).",
        "Danger area of the scalp = loose areolar tissue layer - emissary veins connect to intracranial venous sinuses, risking cavernous sinus thrombosis.",
    ]),
])

# 5. Neuroanatomy
add_section("5. Neuroanatomy", [
    ("Meninges & CSF", [
        "Dura mater and its venous sinuses (superior sagittal, cavernous, transverse); arachnoid mater and subarachnoid space; pia mater.",
        "CSF circulation: produced by choroid plexus in ventricles -> lateral ventricles -> 3rd ventricle -> cerebral aqueduct -> 4th ventricle -> subarachnoid space -> absorbed at arachnoid granulations into superior sagittal sinus.",
    ]),
    ("Blood Supply of Brain", [
        "Circle of Willis - formation (ACA, MCA, PCA, anterior and posterior communicating arteries, internal carotid, basilar) - a very frequently asked short note.",
        "Cerebral artery territories and correlated stroke syndromes (MCA - face/arm weakness; ACA - leg weakness; PCA - visual field defects).",
        "Internal capsule - parts (anterior limb, genu, posterior limb) and tracts carried; lacunar infarcts causing pure motor/sensory stroke.",
    ]),
    ("Cranial Nerves", [
        "Nuclei location (midbrain, pons, medulla), course and function of each of the 12 cranial nerves.",
        "High-yield lesions: CN III (ptosis, dilated pupil, down-and-out eye), CN IV, CN VI (diplopia), CN VII (facial palsy), CN X (hoarseness, gag reflex), CN XII (tongue deviation).",
    ]),
    ("Spinal Cord & ANS", [
        "Ascending tracts - dorsal column (fine touch/proprioception), spinothalamic (pain/temperature).",
        "Descending tract - corticospinal tract (voluntary motor control).",
        "Clinical correlations: Brown-Sequard syndrome, syringomyelia (spinothalamic loss with preserved dorsal column).",
        "Autonomic nervous system - sympathetic chain, cranial and sacral parasympathetic outflow; Horner's syndrome (ptosis, miosis, anhidrosis).",
    ]),
])

# 6. Upper Limb
add_section("6. Upper Limb", [
    ("Axilla & Brachial Plexus", [
        "Axilla - boundaries, contents (axillary artery/vein, cords of brachial plexus, lymph nodes) and relevance to axillary node clearance in breast carcinoma.",
        "Axillary artery - 3 parts relative to pectoralis minor, and branches of each part.",
        "Brachial plexus - roots (C5-T1), trunks, divisions, cords, and terminal branches; relation to axillary artery.",
        "Applied: Erb's palsy (C5-C6, 'waiter's tip' deformity), Klumpke's palsy (C8-T1, claw hand + Horner's syndrome).",
    ]),
    ("Arm & Cubital Fossa", [
        "Compartments of the arm and their nerve supply; radial nerve in the spiral groove - vulnerable in mid-shaft humeral fractures (wrist drop).",
        "Cubital fossa - boundaries and contents (from lateral to medial: biceps tendon, brachial artery, median nerve - mnemonic 'TAN').",
    ]),
    ("Forearm & Wrist", [
        "Flexor and extensor compartments; course of median, ulnar and radial nerves through the forearm.",
        "Carpal tunnel - boundaries (flexor retinaculum), contents, median nerve compression (carpal tunnel syndrome - thenar sensation spared as palmar cutaneous branch arises proximal to the tunnel).",
        "Carpal bones and mnemonic; scaphoid fracture and risk of avascular necrosis due to retrograde blood supply.",
    ]),
    ("Hand & Nerve Injury Summary", [
        "Palmar spaces and their surgical importance; Dupuytren's contracture.",
        "Nerve injury patterns: ulnar claw hand (more marked in distal lesions - 'ulnar paradox'), median claw ('hand of benediction'), wrist drop (radial), winging of scapula (long thoracic nerve/serratus anterior).",
    ]),
])

# 7. Thorax
add_section("7. Thorax", [
    ("Thoracic Wall & Pleura", [
        "Typical rib features; intercostal space - order of neurovascular bundle (VAN - Vein, Artery, Nerve, superior to inferior) and the 'triangle of safety' for thoracocentesis/chest tube insertion.",
        "Pleura - parietal and visceral layers, pleural recesses (costodiaphragmatic recess) - clinical correlation with pneumothorax and pleural effusion.",
    ]),
    ("Lungs & Mediastinum", [
        "Lobes, fissures, bronchopulmonary segments, and structures at the root/hilum of each lung.",
        "Mediastinum - subdivisions (superior, anterior, middle, posterior) and key contents of each.",
    ]),
    ("Heart", [
        "Chambers, valves, borders and surfaces of the heart on surface anatomy/imaging.",
        "Coronary arteries (RCA, LCA - LAD and circumflex) and their territories; venous drainage via coronary sinus.",
        "Conducting system - SA node, AV node, bundle of His, Purkinje fibres; clinical correlation with arrhythmias/heart block.",
        "Pericardium - fibrous and serous layers, pericardial sinuses, cardiac tamponade.",
    ]),
    ("Great Vessels & Diaphragm", [
        "Arch of aorta - branches (brachiocephalic, left common carotid, left subclavian) and relations.",
        "Formation of SVC and IVC; azygos venous system as a collateral pathway.",
        "Thymus - location, embryological origin (3rd pharyngeal pouch), age-related involution.",
        "Diaphragm - openings (caval, oesophageal, aortic) and structures passing through each; phrenic nerve supply; congenital diaphragmatic hernia.",
    ]),
])

# 8. Systematic Embryology
add_section("8. Systematic Embryology (Linked to Above Regions)", [
    ("Pharyngeal Apparatus", [
        "Pharyngeal arches (1st-6th) - cartilage, muscle, nerve and artery derivative of each (classic table-based long/short answer).",
        "Pharyngeal pouches - 1st (tympanic cavity/tube), 2nd (palatine tonsil), 3rd (inferior parathyroid + thymus), 4th (superior parathyroid).",
        "Pharyngeal clefts - only 1st persists (external auditory meatus); persistence of others causes branchial cysts/fistulae.",
    ]),
    ("Face & Palate", [
        "Development of the face from frontonasal, maxillary and mandibular prominences.",
        "Palate development and fusion of palatine shelves - failure causes cleft lip/palate (very high-yield applied embryology topic).",
    ]),
    ("Thyroid & Neck Structures", [
        "Thyroid gland develops from foramen cecum at the tongue base and descends via the thyroglossal duct - persistence causes thyroglossal cyst (moves with tongue protrusion, unlike a branchial cyst).",
    ]),
    ("Heart & Great Vessels", [
        "Primitive heart tube formation and cardiac looping.",
        "Septation of atria (septum primum/secundum, foramen ovale) and ventricles - clinical correlation with ASD and VSD.",
        "Aortic arch derivatives (arches 1-6) and anomalies (patent ductus arteriosus, coarctation of aorta).",
        "Fetal circulation shunts - foramen ovale, ductus arteriosus, ductus venosus - and their postnatal closure/remnants.",
    ]),
    ("Diaphragm & Respiratory System", [
        "Diaphragm develops from septum transversum, pleuroperitoneal membranes, dorsal mesentery of oesophagus, and body wall - failure of pleuroperitoneal fold fusion causes congenital diaphragmatic hernia (usually left, foramen of Bochdalek).",
        "Respiratory system - laryngotracheal groove/tube from foregut; lung bud branching; tracheoesophageal fistula as a classic anomaly of incomplete septation.",
    ]),
    ("Neural Tube Defects", [
        "Failure of neuropore closure - anencephaly (cranial) and spina bifida (caudal); folic acid supplementation reduces risk.",
    ]),
])

elements.append(Spacer(1, 10))
elements.append(Paragraph("Exam strategy: prioritise Brachial Plexus, Facial Nerve, Circle of Willis, Heart "
                           "(gross + conduction), Pharyngeal Apparatus, and Cleft Lip/Palate - these recur most "
                           "often as long answers and short notes across OUHS Anatomy Paper 1 sittings.",
                           ParagraphStyle('note', parent=body, fontName='Helvetica-Oblique', spaceBefore=6)))

doc.build(elements)
print("Study guide PDF generated.")