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

OUTPUT = "/tmp/workspace/ent-ear-anatomy/ENT_Ear_Anatomy.pdf"

# ── Colour palette ──────────────────────────────────────────────────────────
C_DEEP_BLUE   = HexColor("#1A3A5C")   # title / major headings
C_TEAL        = HexColor("#0B7A75")   # section banners
C_ORANGE      = HexColor("#E07B39")   # sub-section headings
C_GOLD        = HexColor("#F4B942")   # accent / key-point boxes
C_LIGHT_TEAL  = HexColor("#D0EFED")   # section banner bg
C_LIGHT_ORANGE= HexColor("#FFF0E6")   # sub-section bg
C_LIGHT_BLUE  = HexColor("#EBF3FA")   # table alternating row
C_KEY_BG      = HexColor("#FFFBE6")   # key-points background
C_RED         = HexColor("#C0392B")   # clinical notes
C_LIGHT_RED   = HexColor("#FDEDEC")   # clinical box bg
C_GREEN       = HexColor("#1D6A3A")   # mnemonic headings
C_LIGHT_GREEN = HexColor("#E8F8F0")   # mnemonic box bg
C_WHITE       = colors.white
C_BLACK       = colors.black
C_GRAY        = HexColor("#555555")
C_LIGHT_GRAY  = HexColor("#F2F2F2")

# ── Page template with header/footer ────────────────────────────────────────
def make_page(canvas, doc):
    canvas.saveState()
    w, h = A4
    # Top stripe
    canvas.setFillColor(C_DEEP_BLUE)
    canvas.rect(0, h - 18*mm, w, 18*mm, fill=1, stroke=0)
    canvas.setFillColor(C_WHITE)
    canvas.setFont("Helvetica-Bold", 11)
    canvas.drawString(15*mm, h - 12*mm, "ENT EAR ANATOMY")
    canvas.setFont("Helvetica", 9)
    canvas.drawRightString(w - 15*mm, h - 12*mm, "Cummings Otolaryngology | Gray's Anatomy")
    # Bottom stripe
    canvas.setFillColor(C_DEEP_BLUE)
    canvas.rect(0, 0, w, 10*mm, fill=1, stroke=0)
    canvas.setFillColor(C_GOLD)
    canvas.setFont("Helvetica-Bold", 8)
    canvas.drawCentredString(w / 2, 3.5*mm, f"Page {doc.page}")
    canvas.restoreState()

# ── Document ─────────────────────────────────────────────────────────────────
doc = BaseDocTemplate(
    OUTPUT,
    pagesize=A4,
    leftMargin=18*mm,
    rightMargin=18*mm,
    topMargin=24*mm,
    bottomMargin=18*mm,
    title="ENT Ear Anatomy",
    author="Orris Medical AI",
    subject="Structured colour notes on ear anatomy",
)
frame = Frame(
    doc.leftMargin, doc.bottomMargin,
    A4[0] - doc.leftMargin - doc.rightMargin,
    A4[1] - doc.topMargin - doc.bottomMargin,
    id="main"
)
doc.addPageTemplates([PageTemplate(id="main", frames=frame, onPage=make_page)])

# ── Styles ───────────────────────────────────────────────────────────────────
base = getSampleStyleSheet()

def S(name, parent="Normal", **kw):
    return ParagraphStyle(name, parent=base[parent], **kw)

title_s = S("Title", "Normal",
    fontName="Helvetica-Bold", fontSize=26, textColor=C_DEEP_BLUE,
    spaceAfter=4, leading=30, alignment=TA_CENTER)

subtitle_s = S("Subtitle", "Normal",
    fontName="Helvetica", fontSize=13, textColor=C_TEAL,
    spaceAfter=2, leading=16, alignment=TA_CENTER)

banner_s = S("Banner", "Normal",
    fontName="Helvetica-Bold", fontSize=14, textColor=C_WHITE,
    spaceAfter=0, leading=18, leftIndent=4)

sub_s = S("Sub", "Normal",
    fontName="Helvetica-Bold", fontSize=11, textColor=C_ORANGE,
    spaceAfter=3, leading=14, leftIndent=2)

body_s = S("Body", "Normal",
    fontName="Helvetica", fontSize=9.5, textColor=C_GRAY,
    spaceAfter=4, leading=14, alignment=TA_JUSTIFY)

bullet_s = S("Bullet", "Normal",
    fontName="Helvetica", fontSize=9.5, textColor=C_GRAY,
    spaceAfter=2, leading=13, leftIndent=12, bulletIndent=4)

kp_s = S("KP", "Normal",
    fontName="Helvetica", fontSize=9, textColor=C_DEEP_BLUE,
    spaceAfter=3, leading=13, leftIndent=8)

clin_s = S("Clin", "Normal",
    fontName="Helvetica-Oblique", fontSize=9, textColor=C_RED,
    spaceAfter=3, leading=13, leftIndent=8)

mnem_s = S("Mnem", "Normal",
    fontName="Helvetica-Bold", fontSize=9, textColor=C_GREEN,
    spaceAfter=3, leading=13, leftIndent=8)

label_s = S("Label", "Normal",
    fontName="Helvetica-Bold", fontSize=9, textColor=C_DEEP_BLUE,
    leading=12)

val_s = S("Val", "Normal",
    fontName="Helvetica", fontSize=9, textColor=C_GRAY,
    leading=12)

tbl_head_s = S("TblHead", "Normal",
    fontName="Helvetica-Bold", fontSize=9, textColor=C_WHITE,
    leading=12, alignment=TA_CENTER)

tbl_cell_s = S("TblCell", "Normal",
    fontName="Helvetica", fontSize=8.5, textColor=C_GRAY,
    leading=12)

# ── Helper builders ──────────────────────────────────────────────────────────

def section_banner(text):
    """Coloured banner for major section."""
    t = Table([[Paragraph(text, banner_s)]], colWidths=[174*mm])
    t.setStyle(TableStyle([
        ("BACKGROUND", (0,0), (-1,-1), C_TEAL),
        ("TOPPADDING", (0,0), (-1,-1), 6),
        ("BOTTOMPADDING", (0,0), (-1,-1), 6),
        ("LEFTPADDING", (0,0), (-1,-1), 8),
        ("ROUNDEDCORNERS", [4,4,4,4]),
    ]))
    return t

def sub_heading(text):
    t = Table([[Paragraph(text, sub_s)]], colWidths=[174*mm])
    t.setStyle(TableStyle([
        ("BACKGROUND", (0,0), (-1,-1), C_LIGHT_ORANGE),
        ("TOPPADDING", (0,0), (-1,-1), 4),
        ("BOTTOMPADDING", (0,0), (-1,-1), 4),
        ("LEFTPADDING", (0,0), (-1,-1), 6),
        ("LINEBELOW", (0,0), (-1,-1), 1, C_ORANGE),
    ]))
    return t

def key_points_box(points):
    rows = [[Paragraph("⭐  KEY POINTS", S("KPH","Normal",
                fontName="Helvetica-Bold", fontSize=10, textColor=C_GOLD,
                leading=13))]]
    for p in points:
        rows.append([Paragraph(f"• {p}", kp_s)])
    t = Table(rows, colWidths=[174*mm])
    t.setStyle(TableStyle([
        ("BACKGROUND", (0,0), (-1,-1), C_KEY_BG),
        ("TOPPADDING", (0,0), (-1,-1), 4),
        ("BOTTOMPADDING", (0,0), (-1,-1), 4),
        ("LEFTPADDING", (0,0), (-1,-1), 10),
        ("BOX", (0,0), (-1,-1), 1.5, C_GOLD),
        ("LINEBELOW", (0,0), (0,0), 1, C_GOLD),
    ]))
    return t

def clinical_box(points):
    rows = [[Paragraph("🩺  CLINICAL NOTES", S("CN","Normal",
                fontName="Helvetica-Bold", fontSize=10, textColor=C_RED,
                leading=13))]]
    for p in points:
        rows.append([Paragraph(f"• {p}", clin_s)])
    t = Table(rows, colWidths=[174*mm])
    t.setStyle(TableStyle([
        ("BACKGROUND", (0,0), (-1,-1), C_LIGHT_RED),
        ("TOPPADDING", (0,0), (-1,-1), 4),
        ("BOTTOMPADDING", (0,0), (-1,-1), 4),
        ("LEFTPADDING", (0,0), (-1,-1), 10),
        ("BOX", (0,0), (-1,-1), 1.5, C_RED),
    ]))
    return t

def mnemonic_box(title, content):
    rows = [
        [Paragraph(f"💡  MNEMONIC: {title}", S("MH","Normal",
                fontName="Helvetica-Bold", fontSize=10, textColor=C_GREEN,
                leading=13))],
        [Paragraph(content, mnem_s)],
    ]
    t = Table(rows, colWidths=[174*mm])
    t.setStyle(TableStyle([
        ("BACKGROUND", (0,0), (-1,-1), C_LIGHT_GREEN),
        ("TOPPADDING", (0,0), (-1,-1), 4),
        ("BOTTOMPADDING", (0,0), (-1,-1), 4),
        ("LEFTPADDING", (0,0), (-1,-1), 10),
        ("BOX", (0,0), (-1,-1), 1.5, C_GREEN),
    ]))
    return t

def two_col_table(headers, rows_data, col_widths=None):
    if col_widths is None:
        col_widths = [60*mm, 114*mm]
    header_row = [Paragraph(h, tbl_head_s) for h in headers]
    table_rows = [header_row]
    for i, row in enumerate(rows_data):
        bg = C_LIGHT_BLUE if i % 2 == 0 else C_WHITE
        table_rows.append([Paragraph(str(c), tbl_cell_s) for c in row])
    t = Table(table_rows, colWidths=col_widths)
    style = [
        ("BACKGROUND", (0, 0), (-1, 0), C_DEEP_BLUE),
        ("ROWBACKGROUNDS", (0, 1), (-1, -1), [C_LIGHT_BLUE, C_WHITE]),
        ("GRID", (0, 0), (-1, -1), 0.5, HexColor("#CCCCCC")),
        ("TOPPADDING", (0, 0), (-1, -1), 4),
        ("BOTTOMPADDING", (0, 0), (-1, -1), 4),
        ("LEFTPADDING", (0, 0), (-1, -1), 6),
        ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
    ]
    t.setStyle(TableStyle(style))
    return t

def sp(n=4):
    return Spacer(1, n*mm)

def hr():
    return HRFlowable(width="100%", thickness=0.5, color=HexColor("#CCCCCC"), spaceAfter=2*mm)

def bp(text):
    return Paragraph(f"<bullet>&bull;</bullet> {text}", bullet_s)

# ── CONTENT ──────────────────────────────────────────────────────────────────
story = []

# =========== COVER ===========
story += [
    sp(20),
    Paragraph("ENT EAR ANATOMY", title_s),
    sp(2),
    Paragraph("Structured Colour Notes for Medical Students", subtitle_s),
    sp(1),
    Paragraph("Based on Cummings Otolaryngology &amp; Gray's Anatomy", subtitle_s),
    sp(8),
    HRFlowable(width="60%", thickness=3, color=C_GOLD, spaceAfter=6*mm),
    sp(2),
]

# Quick-reference box on cover
cover_data = [
    ["Section", "Topic"],
    ["1", "Overview of the Ear"],
    ["2", "Temporal Bone Osteology"],
    ["3", "External Ear (Auricle + EAC)"],
    ["4", "Tympanic Membrane"],
    ["5", "Middle Ear (Tympanic Cavity)"],
    ["6", "Ossicular Chain"],
    ["7", "Eustachian Tube"],
    ["8", "Inner Ear (Cochlea + Vestibule)"],
    ["9", "Nerve Supply of the Ear"],
    ["10", "Blood Supply of the Ear"],
    ["11", "Embryology Summary"],
    ["12", "Clinical Correlations"],
]
cover_tbl = Table(cover_data, colWidths=[20*mm, 140*mm])
cover_tbl.setStyle(TableStyle([
    ("BACKGROUND", (0,0), (-1,0), C_DEEP_BLUE),
    ("TEXTCOLOR", (0,0), (-1,0), C_WHITE),
    ("FONTNAME", (0,0), (-1,0), "Helvetica-Bold"),
    ("FONTSIZE", (0,0), (-1,0), 10),
    ("ROWBACKGROUNDS", (0,1), (-1,-1), [C_LIGHT_BLUE, C_WHITE]),
    ("FONTNAME", (0,1), (-1,-1), "Helvetica"),
    ("FONTSIZE", (0,1), (-1,-1), 9.5),
    ("GRID", (0,0), (-1,-1), 0.5, HexColor("#CCCCCC")),
    ("ALIGN", (0,0), (0,-1), "CENTER"),
    ("TOPPADDING", (0,0), (-1,-1), 5),
    ("BOTTOMPADDING", (0,0), (-1,-1), 5),
    ("LEFTPADDING", (0,0), (-1,-1), 8),
]))
story += [cover_tbl, sp(6)]
story.append(PageBreak())

# =========== SECTION 1: OVERVIEW ===========
story += [section_banner("SECTION 1 — OVERVIEW OF THE EAR"), sp(3)]
story.append(Paragraph(
    "The ear is a complex sensory organ responsible for both hearing (audition) and balance (vestibular function). "
    "It is divided into three anatomically and functionally distinct regions: the external ear, middle ear, and inner ear. "
    "All three regions are housed within the temporal bone of the skull.",
    body_s))
story += [sp(3)]

# Overview table
story.append(two_col_table(
    ["Region", "Components & Function"],
    [
        ["External Ear", "Auricle (pinna) + External auditory canal (EAC). Collects and funnels sound waves. Acoustic → kinetic energy transfer."],
        ["Middle Ear (Tympanic Cavity)", "Tympanic membrane (TM), ossicles (malleus, incus, stapes), Eustachian tube, mastoid air cells. Amplifies and transmits vibrations."],
        ["Inner Ear (Labyrinth)", "Bony labyrinth: vestibule, semicircular canals, cochlea. Membranous labyrinth within. Converts vibration → electrical impulse (hair cells)."],
    ],
    col_widths=[50*mm, 124*mm]
))
story += [sp(3)]
story.append(key_points_box([
    "Outer ear: acoustic → kinetic energy",
    "Middle ear: increases kinetic energy ~18× (impedance matching)",
    "Inner ear: kinetic → hydraulic → electrical energy",
    "Two sensory organs in inner ear: Organ of Corti (hearing) + Macula/Crista (balance)",
]))
story += [sp(4)]

# =========== SECTION 2: TEMPORAL BONE ===========
story += [section_banner("SECTION 2 — TEMPORAL BONE OSTEOLOGY"), sp(3)]
story.append(Paragraph(
    "The temporal bone forms part of the lateral skull base and houses the entire auditory and vestibular apparatus. "
    "It articulates with the sphenoid, parietal, occipital, and zygomatic bones.",
    body_s))
story += [sp(3), sub_heading("Four Parts of the Temporal Bone"), sp(2)]

story.append(two_col_table(
    ["Part", "Key Features"],
    [
        ["Squamous", "Thin, flat lateral plate. Forms roof of infratemporal fossa. Contains temporal line (~5 mm below middle fossa floor)."],
        ["Mastoid", "Posterior part. Contains mastoid air cells (pneumatised). MacEwen triangle: cribriform area posterior to spine of Henle - marks mastoid antrum."],
        ["Petrous", "Dense, pyramidal. Houses inner ear structures. Contains internal auditory canal (IAC), jugular foramen, carotid canal."],
        ["Tympanic", "Curved plate forming anterior, inferior and posterior walls of EAC. Forms tympanic ring (sulcus for TM)."],
    ],
    col_widths=[40*mm, 134*mm]
))
story += [sp(3)]
story.append(clinical_box([
    "MacEwen triangle - surgical landmark for mastoid antrum (cortical mastoidectomy entry point).",
    "Temporal line: ~5 mm below middle fossa floor - safe reference for dissection.",
    "Stylomastoid foramen: located at anterior limit of digastric groove - facial nerve exits here.",
    "Arcuate eminence: prominence of superior SCC visible on middle fossa floor.",
]))
story += [sp(4)]

# =========== SECTION 3: EXTERNAL EAR ===========
story += [section_banner("SECTION 3 — EXTERNAL EAR"), sp(3)]

story += [sub_heading("3.1 Auricle (Pinna)"), sp(2)]
story.append(Paragraph(
    "The auricle is a funnel-shaped cartilaginous structure that is continuous with the external auditory canal. "
    "Its framework is elastic fibrocartilage covered by tightly adherent perichondrium and skin.",
    body_s))
story += [sp(2)]

auricle_data = [
    ["Structure", "Description"],
    ["Helix", "Curved outer rim of auricle"],
    ["Antihelix", "Inner curved ridge parallel to helix; bifurcates superiorly into crura"],
    ["Tragus", "Small projection anterior to EAC opening"],
    ["Antitragus", "Small projection opposite to tragus"],
    ["Concha", "Deep bowl-shaped depression leading to EAC"],
    ["Fossa triangularis", "Triangular depression between crura of antihelix"],
    ["Scapha", "Groove between helix and antihelix"],
    ["Lobule", "Inferior, fat-filled, non-cartilaginous portion"],
    ["Cymba conchae", "Superior part of concha; bounded by crus of helix"],
]
story.append(two_col_table(auricle_data[0], auricle_data[1:], col_widths=[55*mm, 119*mm]))
story += [sp(3)]

story.append(mnemonic_box(
    "Auricular Hillocks of His",
    "Hillocks 1-3 from 1st arch → Tragus, Helix crus, Helix\n"
    "Hillocks 4-6 from 2nd arch → Antihelix, Antitragus, Lobule\n"
    "Memory: '1st arch = Tragus & Helix (T-H); 2nd arch = Antihelix to Lobule (A-L)'"
))
story += [sp(3)]

story += [sub_heading("3.2 External Auditory Canal (EAC)"), sp(2)]
story.append(Paragraph(
    "The EAC is approximately 2.5 cm in length and is S-shaped. It extends from the concha of the auricle "
    "to the tympanic membrane.",
    body_s))
story += [sp(2)]

eac_data = [
    ["Feature", "Detail"],
    ["Length", "~2.5 cm total"],
    ["Outer 1/3 (Cartilaginous)", "Lateral third. Skin is thick and mobile. Contains sebaceous glands, apocrine (ceruminous) glands, hair follicles."],
    ["Inner 2/3 (Bony)", "Medial two-thirds. Skin is thin, immobile, no glands/hair. Continuous with TM epithelium."],
    ["Isthmus", "Bony-cartilaginous junction; narrowest point of EAC. Site of malignant otitis externa granulations."],
    ["Foramen of Huschke", "Incomplete ossification of anterior bony canal → opening to infratemporal fossa. Pathway for tumour spread to parotid."],
    ["Fissures of Santorini", "Natural defects in cartilaginous EAC → route to superficial parotid lobe."],
    ["Direction", "Lateral portion: directed upward, backward. To straighten EAC: pull pinna up and back (adult), down and back (child)."],
]
story.append(two_col_table(eac_data[0], eac_data[1:], col_widths=[55*mm, 119*mm]))
story += [sp(3)]
story.append(clinical_box([
    "Malignant otitis externa: granulation at bony-cartilaginous junction is pathognomonic.",
    "Failed involution of meatal plug → canal atresia with conductive hearing loss.",
    "En bloc resection needed for EAC malignancies due to spread via foramen of Huschke and fissures of Santorini.",
]))
story += [sp(4), PageBreak()]

# =========== SECTION 4: TYMPANIC MEMBRANE ===========
story += [section_banner("SECTION 4 — TYMPANIC MEMBRANE (TM)"), sp(3)]
story.append(Paragraph(
    "The tympanic membrane (eardrum) forms the medial wall of the EAC and the lateral wall of the middle ear. "
    "It is a four-layered, concave, pearlescent membrane that vibrates in response to sound waves.",
    body_s))
story += [sp(3)]

story += [sub_heading("4.1 Layers of the TM"), sp(2)]
story.append(two_col_table(
    ["Layer", "Details"],
    [
        ["Outer (Epithelial)", "Keratinising stratified squamous epithelium; continuous with EAC skin"],
        ["Outer Fibrous (Radiate)", "Fibres radiate from umbo/manubrium outward — provides structural support"],
        ["Inner Fibrous (Circular)", "Circumferential arrangement at periphery; integrates with annular ligament"],
        ["Inner (Mucosal)", "Simple cuboidal/squamous mucosa; continuous with middle ear mucosa"],
    ],
    col_widths=[55*mm, 119*mm]
))
story += [sp(3)]

story += [sub_heading("4.2 Landmarks of the TM"), sp(2)]
story.append(two_col_table(
    ["Landmark", "Description"],
    [
        ["Umbo", "Central depression; tip of malleus manubrium attaches here"],
        ["Mallear stria", "Light streak from umbo to lateral process of malleus (manubrium visible through TM)"],
        ["Lateral process (short process)", "Small projection of malleus; creates anterior & posterior mallear folds"],
        ["Anterior mallear fold", "Superior demarcation between pars flaccida and pars tensa (anteriorly)"],
        ["Posterior mallear fold", "Superior demarcation between pars flaccida and pars tensa (posteriorly)"],
        ["Pars tensa", "Inferior, thicker portion; has all 4 layers; taut due to fibrous layers"],
        ["Pars flaccida (Shrapnell's membrane)", "Superior, flaccid; lacks fibrous layer; attached to notch of Rivinus"],
        ["Annular ligament", "Fibrocartilaginous ring anchoring TM periphery to tympanic sulcus"],
        ["Light reflex (cone of light)", "Triangular reflection: anterior-inferior quadrant; absent in otitis media"],
        ["Tympanic annulus", "Fibrocartilaginous ring; absent superiorly at notch of Rivinus"],
    ],
    col_widths=[65*mm, 109*mm]
))
story += [sp(3)]

story.append(mnemonic_box(
    "TM Quadrants",
    "Divided into 4 quadrants by manubrium (vertical) + horizontal line through umbo:\n"
    "Antero-superior | Antero-inferior | Postero-superior | Postero-inferior\n"
    "Light reflex = Antero-inferior | Incudostapedial joint visible = Postero-inferior\n"
    "Chorda tympani = Postero-superior | Round window shadow = visible through pars tensa"
))
story += [sp(3)]
story.append(clinical_box([
    "Pars flaccida: most common site for acquired cholesteatoma (lacks fibrous layer, weakest).",
    "Cone of light lost in otitis media with effusion / middle ear effusion.",
    "Traumatic perforation: usually pars tensa (large central perforations); pars flaccida → cholesteatoma.",
    "Retraction pockets of pars flaccida are the earliest sign of attic cholesteatoma.",
]))
story += [sp(4), PageBreak()]

# =========== SECTION 5: MIDDLE EAR ===========
story += [section_banner("SECTION 5 — MIDDLE EAR (TYMPANIC CAVITY)"), sp(3)]
story.append(Paragraph(
    "The middle ear (tympanic cavity) is an air-filled space within the temporal bone connecting the "
    "nasopharynx (via Eustachian tube) to the mastoid air cells (via the aditus and antrum). "
    "Its epithelial lining is columnar ciliated (near ET) and pavement epithelium elsewhere.",
    body_s))
story += [sp(3)]

story += [sub_heading("5.1 Boundaries of the Tympanic Cavity"), sp(2)]
story.append(two_col_table(
    ["Wall", "Boundary & Contents"],
    [
        ["Lateral (membranous)", "Tympanic membrane (pars tensa + pars flaccida); bony tympanic ring superiorly"],
        ["Medial (labyrinthine)", "Promontory (basal cochlea); oval window (with stapes footplate); round window (secondary TM); facial nerve canal (horizontal); lateral semicircular canal prominence"],
        ["Roof (tegmental)", "Tegmen tympani — thin plate of petrous bone separating middle ear from middle cranial fossa"],
        ["Floor (jugular)", "Thin plate overlying jugular bulb; contains tympanic branch of IX (Jacobson's nerve)"],
        ["Anterior (carotid)", "Eustachian tube opening (superiorly); carotid canal below; tensor tympani muscle canal"],
        ["Posterior (mastoid)", "Aditus ad antrum (→ mastoid antrum); pyramid (contains stapedius muscle); chorda tympani enters here"],
    ],
    col_widths=[50*mm, 124*mm]
))
story += [sp(3)]

story += [sub_heading("5.2 Divisions of the Tympanic Cavity"), sp(2)]
story.append(two_col_table(
    ["Division", "Level", "Contents"],
    [
        ["Epitympanum (Attic)", "Above level of TM", "Head of malleus, body of incus, ossicular ligaments, chorda tympani"],
        ["Mesotympanum", "Level of TM (pars tensa)", "Manubrium, long process of incus, stapes, oval window, round window"],
        ["Hypotympanum", "Below level of TM", "Floor; jugular bulb nearby"],
    ],
    col_widths=[40*mm, 40*mm, 94*mm]
))
story += [sp(3)]
story.append(clinical_box([
    "Tegmen tympani erosion: middle fossa CSF leak or meningitis.",
    "High jugular bulb (on floor): risk of bleeding during myringotomy.",
    "Promontory biopsy: do NOT biopsy without imaging — aberrant carotid artery or glomus tumour risk.",
    "Epitympanum and mesotympanum separated by ossicular chain → narrow communication (important in cholesteatoma spread).",
]))
story += [sp(4), PageBreak()]

# =========== SECTION 6: OSSICULAR CHAIN ===========
story += [section_banner("SECTION 6 — OSSICULAR CHAIN"), sp(3)]
story.append(Paragraph(
    "The ossicular chain transmits sound vibrations from the TM to the oval window of the inner ear. "
    "It consists of three bones: the malleus, incus, and stapes — the three smallest bones in the human body.",
    body_s))
story += [sp(3)]

story.append(two_col_table(
    ["Ossicle", "Parts", "Attachments & Notes"],
    [
        ["Malleus (Hammer)", "Head, neck, manubrium (handle), lateral process, anterior process",
         "Manubrium attached to TM (at umbo). Head in epitympanum. Tensor tympani attaches to neck. Most lateral ossicle."],
        ["Incus (Anvil)", "Body, short process (posterior), long process (inferior)",
         "Body articulates with malleus head (incudomalleal joint). Long process descends to lenticular process → stapes head. Most vulnerable ossicle (avascular long process)."],
        ["Stapes (Stirrup)", "Head, neck, anterior crus, posterior crus, footplate",
         "Footplate sits in oval window sealed by annular ligament. Stapedius attaches to neck. Smallest bone in body (~3 mm)."],
    ],
    col_widths=[30*mm, 50*mm, 94*mm]
))
story += [sp(3)]

story += [sub_heading("6.1 Muscles of the Middle Ear"), sp(2)]
story.append(two_col_table(
    ["Muscle", "Origin", "Insertion", "Nerve", "Action"],
    [
        ["Tensor Tympani", "Cartilage of ET + sphenoid", "Manubrium of malleus", "Medial pterygoid nerve (V3)", "Pulls malleus medially; tenses TM; dampens loud sounds"],
        ["Stapedius", "Pyramidal eminence", "Neck of stapes", "Facial nerve (CN VII)", "Pulls stapes posteriorly; protective reflex against loud noise (stapedial reflex)"],
    ],
    col_widths=[28*mm, 32*mm, 32*mm, 36*mm, 46*mm]
))
story += [sp(3)]
story.append(key_points_box([
    "Impedance matching: TM area (~85 mm²) vs oval window (~3.2 mm²) → 17:1 area ratio.",
    "Ossicular lever mechanism adds further ~1.3× amplification → total ~22× pressure gain.",
    "Acoustic reflex (stapedial reflex): bilateral; latency ~25 ms; tests CN VII integrity.",
    "Long process of incus is most vulnerable: single nutrient vessel, no collateral circulation → first to erode in chronic OM.",
]))
story += [sp(3)]
story.append(clinical_box([
    "Ossicular discontinuity (erosion of long process of incus): common cause of conductive hearing loss in CSOM.",
    "Stapedial reflex absent ipsilaterally in Bell's palsy / CN VII lesion distal to nerve to stapedius.",
    "Otosclerosis: abnormal bone growth at footplate → fixation of stapes → conductive hearing loss.",
]))
story += [sp(4), PageBreak()]

# =========== SECTION 7: EUSTACHIAN TUBE ===========
story += [section_banner("SECTION 7 — EUSTACHIAN (PHARYNGOTYMPANIC) TUBE"), sp(3)]
story.append(Paragraph(
    "The Eustachian tube (auditory tube / pharyngotympanic tube) connects the anterior wall of the middle ear "
    "to the nasopharynx. Its primary function is pressure equalisation of the middle ear cleft.",
    body_s))
story += [sp(3)]

story.append(two_col_table(
    ["Feature", "Details"],
    [
        ["Length", "~35-40 mm in adults"],
        ["Direction", "Runs anteromedially, inferiorly from middle ear to nasopharynx"],
        ["Isthmus", "Narrowest point at bony-cartilaginous junction (~1 mm)"],
        ["Bony portion", "Posterior 1/3; rigid; always open"],
        ["Cartilaginous portion", "Anterior 2/3; normally closed at rest; opens with swallowing/yawning"],
        ["Opening mechanism", "Tensor veli palatini (primary), levator veli palatini & salpingopharyngeus (assist) — all via V3"],
        ["Pharyngeal opening", "Torus tubarius: cartilaginous elevation on lateral nasopharynx wall"],
        ["Infant vs Adult", "Infant ET: shorter (~18 mm), horizontal, wider → more prone to middle ear infections"],
        ["Functions", "1. Pressure equalisation  2. Mucociliary clearance (toward pharynx)  3. Protective (prevents reflux)"],
    ],
    col_widths=[50*mm, 124*mm]
))
story += [sp(3)]
story.append(clinical_box([
    "ET dysfunction → negative middle ear pressure → retraction pockets → OME (glue ear).",
    "Adenoid hypertrophy in children → ET blockage → recurrent otitis media.",
    "Barotrauma: inability to equalise pressure during descent (flying/diving); TM retraction or rupture.",
    "Patulous (abnormally patent) ET: autophony, breathing sounds heard in ear, relieved by head-down position.",
]))
story += [sp(4), PageBreak()]

# =========== SECTION 8: INNER EAR ===========
story += [section_banner("SECTION 8 — INNER EAR (COCHLEA, VESTIBULE, SCCs)"), sp(3)]
story.append(Paragraph(
    "The inner ear (labyrinth) is embedded within the petrous part of the temporal bone. It consists of "
    "a bony labyrinth housing a membranous labyrinth. The inner ear serves two functions: hearing (cochlea) "
    "and balance (vestibule + semicircular canals).",
    body_s))
story += [sp(3)]

story += [sub_heading("8.1 Fluids"), sp(2)]
story.append(two_col_table(
    ["Fluid", "Location", "Composition", "Function"],
    [
        ["Perilymph", "Between bony and membranous labyrinth (scala vestibuli & scala tympani)", "Similar to extracellular fluid (high Na⁺, low K⁺)", "Transmits hydraulic vibrations"],
        ["Endolymph", "Inside membranous labyrinth (scala media / endolymphatic duct)", "Similar to intracellular fluid (high K⁺, low Na⁺)", "Bathes hair cells; K⁺ influx triggers depolarisation"],
    ],
    col_widths=[30*mm, 50*mm, 50*mm, 44*mm]
))
story += [sp(3)]

story += [sub_heading("8.2 Cochlea"), sp(2)]
story.append(Paragraph(
    "The cochlea is a snail-shaped structure with 2.5 turns. It encodes sound frequency (tonotopy) along "
    "its length: high frequency at base, low frequency at apex.",
    body_s))
story += [sp(2)]
story.append(two_col_table(
    ["Structure", "Details"],
    [
        ["Scala vestibuli", "Perilymph-filled; begins at oval window; connects to scala tympani at helicotrema (apex)"],
        ["Scala tympani", "Perilymph-filled; terminates at round window (secondary TM)"],
        ["Scala media (cochlear duct)", "Endolymph-filled membranous duct; contains Organ of Corti"],
        ["Organ of Corti", "Sensory epithelium on basilar membrane. Contains inner (1 row) and outer (3 rows) hair cells. Inner hair cells: primary auditory transducers."],
        ["Basilar membrane", "Tonotopic: narrow/stiff at base (high freq) → wide/floppy at apex (low freq)"],
        ["Reissner's membrane", "Separates scala vestibuli from scala media; maintains endolymph composition"],
        ["Stria vascularis", "Lateral wall of scala media; produces endolymph; high blood supply"],
        ["Tectorial membrane", "Gelatinous membrane overlying hair cells; stereocilia of outer HCs embedded in it"],
        ["Helicotrema", "Apex of cochlea; connection between scala vestibuli and scala tympani"],
        ["Round window", "Secondary TM; allows perilymph displacement during sound transmission"],
    ],
    col_widths=[55*mm, 119*mm]
))
story += [sp(3)]

story += [sub_heading("8.3 Vestibule & Semicircular Canals"), sp(2)]
story.append(two_col_table(
    ["Structure", "Sensory Organ", "Detects"],
    [
        ["Utricle (horizontal macula)", "Macula utriculi", "Linear acceleration (horizontal); head tilt"],
        ["Saccule (vertical macula)", "Macula sacculi", "Linear acceleration (vertical); gravity"],
        ["Anterior (superior) SCC", "Crista ampullaris", "Rotation in sagittal plane (pitching - head nod)"],
        ["Posterior SCC", "Crista ampullaris", "Rotation in coronal plane (rolling - head tilt)"],
        ["Lateral (horizontal) SCC", "Crista ampullaris", "Rotation in horizontal plane (turning of head)"],
    ],
    col_widths=[50*mm, 45*mm, 79*mm]
))
story += [sp(3)]
story.append(key_points_box([
    "SCCs develop in order: superior → posterior → lateral",
    "Otoliths (otoconia = calcium carbonate crystals) on macula; dislodged otoconia cause BPPV",
    "Endolymphatic sac (in posterior fossa dura): regulates endolymph; implicated in Meniere's disease",
    "Cochlear duct: 10 weeks → 2.5 turns; 20 weeks → full adult size; 21 weeks → organ of Corti functional",
]))
story += [sp(3)]
story.append(clinical_box([
    "BPPV: canalith repositioning (Epley manoeuvre) — posterior canal most commonly affected.",
    "Meniere's disease: endolymphatic hydrops → low-frequency SNHL + tinnitus + episodic vertigo.",
    "Cochlear implants: electrode array placed in scala tympani via round window or cochleostomy.",
    "Presbycusis: high-frequency SNHL first (base of cochlea affected by hair cell loss).",
]))
story += [sp(4), PageBreak()]

# =========== SECTION 9: NERVE SUPPLY ===========
story += [section_banner("SECTION 9 — NERVE SUPPLY OF THE EAR"), sp(3)]

story.append(two_col_table(
    ["Region", "Nerve(s)", "Details"],
    [
        ["Auricle — anterior surface", "Auriculotemporal (V3 — mandibular)", "Greater part of anterior auricle & tragus"],
        ["Auricle — posterior surface", "Greater auricular nerve (C2, C3)", "Most of posterior auricle and lobule"],
        ["Auricle — posterior surface (sup)", "Lesser occipital nerve (C2)", "Superior posterior auricle"],
        ["EAC anterior wall", "Auriculotemporal (V3)", "Anterior + superior EAC wall and anterior TM"],
        ["EAC posterior wall", "Arnold's nerve (auricular branch of CN X)", "Posterior EAC wall; cough reflex on ear examination"],
        ["EAC (additional)", "Facial nerve (CN VII) cutaneous branch", "Small area of EAC/concha"],
        ["TM outer layer", "Auriculotemporal (V3)", "Outer epithelial layer"],
        ["TM inner layer", "Tympanic plexus (IX)", "Mucosal (inner) layer of TM"],
        ["Middle ear mucosa", "Tympanic plexus (Jacobson's nerve, CN IX)", "Tympanic branch of glossopharyngeal nerve"],
        ["Inner ear — hearing", "Cochlear nerve (CN VIII)", "Spiral ganglion → cochlear nucleus"],
        ["Inner ear — balance", "Vestibular nerve (CN VIII)", "Scarpa's ganglion → vestibular nuclei"],
    ],
    col_widths=[45*mm, 50*mm, 79*mm]
))
story += [sp(3)]
story.append(clinical_box([
    "Arnold's nerve reflex: stimulation of posterior EAC (ear syringing, hearing aids) → cough via CN X. Basis for 'ear-cough reflex'.",
    "Referred otalgia: ear pain without local pathology → via CN V (dental), CN IX (tonsil), CN X (larynx), C2/C3 (neck).",
    "Jacobson's nerve (tympanic plexus) gives rise to glomus tympanicum tumour on promontory.",
]))
story += [sp(4), PageBreak()]

# =========== SECTION 10: BLOOD SUPPLY ===========
story += [section_banner("SECTION 10 — BLOOD SUPPLY OF THE EAR"), sp(3)]

story.append(two_col_table(
    ["Region", "Arteries", "Notes"],
    [
        ["Auricle (anterior)", "Superficial temporal artery (ECA)", "Branch of ECA"],
        ["Auricle (posterior)", "Posterior auricular artery (ECA)", "Branch of ECA; also supplies mastoid"],
        ["EAC & TM (outer)", "Posterior auricular + superficial temporal (ECA)", "External supply"],
        ["TM (inner)", "Anterior tympanic artery (maxillary a.) + posterior tympanic (posterior auricular a.)", "Forms vascular circle around TM"],
        ["Middle ear", "Inferior tympanic (ascending pharyngeal) + anterior tympanic (maxillary) + posterior tympanic + superior petrosal (middle meningeal) + caroticotympanic aa.", "Tympanic plexus"],
        ["Inner ear", "Internal auditory (labyrinthine) artery → branch of AICA (anterior inferior cerebellar artery)", "Terminal artery; no collaterals → sudden SNHL"],
    ],
    col_widths=[35*mm, 70*mm, 69*mm]
))
story += [sp(3)]
story.append(key_points_box([
    "Labyrinthine (internal auditory) artery is a terminal branch of AICA - NO collaterals",
    "AICA infarct can cause sudden-onset ipsilateral SNHL + vertigo + facial palsy (lateral pontine syndrome)",
    "Labyrinthine segment of facial nerve is watershed area between vertebrobasilar and ECA supply → vulnerable in viral infections (Bell's palsy / Ramsay Hunt)",
]))
story += [sp(4), PageBreak()]

# =========== SECTION 11: EMBRYOLOGY ===========
story += [section_banner("SECTION 11 — EMBRYOLOGY OF THE EAR"), sp(3)]

story += [sub_heading("11.1 External Ear Development"), sp(2)]
story.append(two_col_table(
    ["Structure", "Origin", "Week"],
    [
        ["Auricle", "Hillocks of His (6 condensations): H1-H3 from 1st arch, H4-H6 from 2nd arch", "5-12 weeks"],
        ["EAC", "Dorsal portion of 1st branchial groove (ectoderm)", "4-28 weeks"],
        ["TM (outer layer)", "Ectoderm of 1st branchial groove", "—"],
        ["TM (inner layer)", "Endoderm of 1st pharyngeal pouch", "—"],
        ["TM (fibrous layer)", "Mesoderm of 1st/2nd branchial arch", "—"],
    ],
    col_widths=[45*mm, 95*mm, 34*mm]
))
story += [sp(3)]

story += [sub_heading("11.2 Middle Ear Development"), sp(2)]
story.append(two_col_table(
    ["Structure", "Origin"],
    [
        ["Tympanic cavity + ET lining", "Endoderm of 1st pharyngeal pouch (tubotympanic recess)"],
        ["Malleus + Incus", "Meckel's cartilage (1st arch) — head of malleus + body & short process of incus"],
        ["Manubrium of malleus", "Meckel's + Reichert's cartilage"],
        ["Stapes (most parts)", "Reichert's cartilage (2nd arch) — stapes, styloid, stylohyoid ligament"],
        ["Stapes footplate", "Otic capsule (mesoderm)"],
        ["Tensor tympani", "1st branchial arch (innervated by V3)"],
        ["Stapedius", "2nd branchial arch (innervated by VII)"],
    ],
    col_widths=[50*mm, 124*mm]
))
story += [sp(3)]

story += [sub_heading("11.3 Inner Ear Development"), sp(2)]
story.append(two_col_table(
    ["Week", "Developmental Event"],
    [
        ["3 weeks", "Otic placode appears (thickened ectoderm on surface)"],
        ["3-4 weeks", "Otic placode invaginates → otic cup → otic vesicle (otocyst)"],
        ["5 weeks", "Endolymphatic duct forms (first structure). Otocyst divides into pars superior and pars inferior."],
        ["5-6 weeks", "Pars superior → utricle, ampullae, semicircular canals (superior → posterior → lateral order)"],
        ["5-6 weeks", "Pars inferior → saccule + cochlear duct (coils 2.5 turns by 10 weeks)"],
        ["20 weeks", "Cochlear duct reaches full adult size"],
        ["21 weeks", "Organ of Corti becomes functional"],
    ],
    col_widths=[25*mm, 149*mm]
))
story += [sp(3)]
story.append(clinical_box([
    "Meatal plug failure → congenital canal atresia (conductive HL; requires BAHA or surgical reconstruction).",
    "Thalidomide / rubella / CMV in 1st trimester → sensorineural or mixed HL (inner ear malformation).",
    "Michel aplasia: complete absence of inner ear (most severe malformation).",
    "Mondini dysplasia: incomplete cochlear coiling (1.5 turns instead of 2.5) → congenital SNHL.",
]))
story += [sp(4), PageBreak()]

# =========== SECTION 12: CLINICAL CORRELATIONS SUMMARY ===========
story += [section_banner("SECTION 12 — CLINICAL CORRELATIONS SUMMARY"), sp(3)]

story.append(two_col_table(
    ["Condition", "Key Anatomical Basis"],
    [
        ["Otitis Externa (Swimmer's ear)", "Infection of EAC skin; Pseudomonas commonest. Tragal tenderness pathognomonic."],
        ["Malignant Otitis Externa", "Osteomyelitis of temporal bone; granulation at B-C junction; CN VII at stylomastoid foramen at risk."],
        ["Acute Otitis Media (AOM)", "Middle ear mucosal infection via ET; TM bulging/erythema; pars tensa perforation if ruptures."],
        ["Otitis Media with Effusion (OME / Glue Ear)", "ET dysfunction → negative pressure → transudate; dull retracted TM with fluid level; conductive HL."],
        ["Cholesteatoma", "Keratoma in middle ear; pars flaccida (Attic/acquired); erodes ossicles, SCCs, tegmen, facial canal."],
        ["Otosclerosis", "Abnormal bone at oval window → stapes fixation → conductive HL; Schwartze sign (flamingo pink promontory)."],
        ["Meniere's Disease", "Endolymphatic hydrops; low-freq SNHL + episodic vertigo + tinnitus + aural fullness."],
        ["BPPV", "Otoconia dislodged from macula into SCC (posterior most common); rotatory nystagmus on Dix-Hallpike."],
        ["Acoustic Neuroma (Vestibular Schwannoma)", "CN VIII tumour in IAC/CPA; unilateral progressive SNHL + tinnitus + imbalance."],
        ["Bell's Palsy", "CN VII palsy; stapedial reflex absent; hyperacusis due to loss of stapedius function."],
        ["Presbycusis", "Age-related SNHL; hair cell loss at cochlear base → high-frequency loss first."],
    ],
    col_widths=[55*mm, 119*mm]
))
story += [sp(4)]

# Final page reference box
story.append(mnemonic_box(
    "Quick Anatomy Summary — 3-2-1 Rule",
    "3 ossicles (malleus-incus-stapes) | 3 semicircular canals | 3 layers of TM (fibrous: 2 layers)\n"
    "2 muscles: tensor tympani (V3) + stapedius (VII) | 2 fluids: perilymph + endolymph\n"
    "1 Eustachian tube | 1 oval window | 1 round window | 1 labyrinthine artery (terminal!)"
))

# ── Build ────────────────────────────────────────────────────────────────────
doc.build(story)
print("PDF generated:", OUTPUT)