const pptxgen = require("pptxgenjs");

const pres = new pptxgen();
pres.layout = "LAYOUT_16x9";
pres.title = "Normal Breast Anatomy and Histology";
pres.author = "Medical Education";

// ── COLOUR PALETTE ──────────────────────────────────────────────────────────
const C = {
  navy:      "0D2B45",   // dominant dark (title BG, accent bars)
  teal:      "1A7A8A",   // supporting
  rose:      "C0395E",   // accent (headings, highlights)
  cream:     "F5F0EB",   // light slide BG
  white:     "FFFFFF",
  lightTeal: "D4EEF1",   // content card BG
  lightGray: "EAE8E4",   // alt content BG
  darkText:  "1A1A2E",
  midText:   "3A3A5C",
};

// ── HELPERS ──────────────────────────────────────────────────────────────────
function addSlide(bg) {
  const s = pres.addSlide();
  s.background = { color: bg || C.cream };
  return s;
}

function titleBar(s, label, yPos = 0) {
  s.addShape(pres.ShapeType.rect, { x: 0, y: yPos, w: 10, h: 0.55, fill: { color: C.navy } });
  s.addText(label, {
    x: 0.2, y: yPos, w: 9.6, h: 0.55, fontSize: 9, color: C.white,
    bold: true, valign: "middle", charSpacing: 2
  });
}

function sectionHeading(s, text, x, y, w, color) {
  s.addShape(pres.ShapeType.rect, { x, y, w, h: 0.06, fill: { color: color || C.teal } });
  s.addText(text, {
    x, y: y + 0.1, w, h: 0.5, fontSize: 16, bold: true,
    color: color || C.teal, margin: 0
  });
}

function accentLine(s, x, y, w, color) {
  s.addShape(pres.ShapeType.rect, { x, y, w, h: 0.05, fill: { color: color || C.rose } });
}

function card(s, x, y, w, h, fillColor) {
  s.addShape(pres.ShapeType.roundRect, {
    x, y, w, h,
    fill: { color: fillColor || C.lightTeal },
    line: { color: C.teal, width: 1 },
    rectRadius: 0.08
  });
}

function bullets(s, items, x, y, w, h, opts = {}) {
  const textArr = items.map((t, i) => ({
    text: t,
    options: { bullet: { indent: 12 }, breakLine: i < items.length - 1, fontSize: opts.fontSize || 13, color: opts.color || C.darkText }
  }));
  s.addText(textArr, { x, y, w, h, valign: "top", ...opts });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 1 – TITLE
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.navy);
  // Decorative shapes
  s.addShape(pres.ShapeType.rect, { x: 0, y: 0, w: 0.25, h: 5.625, fill: { color: C.rose } });
  s.addShape(pres.ShapeType.rect, { x: 0.25, y: 0, w: 0.12, h: 5.625, fill: { color: C.teal } });
  s.addShape(pres.ShapeType.rect, { x: 0, y: 4.8, w: 10, h: 0.825, fill: { color: "091E30" } });

  s.addText("NORMAL BREAST", {
    x: 0.7, y: 1.0, w: 8.8, h: 0.9, fontSize: 44, bold: true,
    color: C.white, charSpacing: 4, align: "center"
  });
  s.addText("ANATOMY & HISTOLOGY", {
    x: 0.7, y: 1.85, w: 8.8, h: 0.8, fontSize: 36, bold: false,
    color: C.rose, charSpacing: 3, align: "center"
  });
  accentLine(s, 2, 2.75, 6, C.teal);
  s.addText("A comprehensive overview of gross anatomy, microstructure,\nvascular supply, lymphatics, and physiological changes", {
    x: 0.7, y: 2.85, w: 8.8, h: 0.9, fontSize: 13, color: "A8C8D0",
    align: "center", italic: true
  });
  s.addText("Sources: Gray's Anatomy for Students | Robbins & Kumar Basic Pathology\nHistology: A Text and Atlas | Robbins, Cotran & Kumar Pathologic Basis of Disease", {
    x: 0.7, y: 4.85, w: 8.8, h: 0.6, fontSize: 9, color: "7090A0",
    align: "center"
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 2 – OUTLINE
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.navy);
  titleBar(s, "PRESENTATION OUTLINE");
  s.addText("What We Will Cover", {
    x: 0.5, y: 0.65, w: 9, h: 0.6, fontSize: 26, bold: true,
    color: C.rose, align: "center"
  });

  const topics = [
    ["01", "Introduction & Overview of the Breast"],
    ["02", "Gross Anatomy – Position & Extent"],
    ["03", "External Features – Nipple & Areola"],
    ["04", "Internal Structure – Lobes, Lobules & Ducts"],
    ["05", "Suspensory Ligaments of Cooper"],
    ["06", "Arterial Supply"],
    ["07", "Venous Drainage"],
    ["08", "Lymphatic Drainage"],
    ["09", "Innervation"],
    ["10", "Histology – Overview of Cell Types"],
    ["11", "Histology – Terminal Duct Lobular Unit (TDLU)"],
    ["12", "Histology – Ductal System & Nipple"],
    ["13", "Histology – Stromal Components"],
    ["14", "Physiological Changes (Puberty, Menstrual Cycle, Pregnancy, Involution)"],
    ["15", "Summary & Clinical Correlations"],
  ];

  const cols = [topics.slice(0, 8), topics.slice(8, 15)];
  const xs = [0.4, 5.3];
  const startY = 1.35;

  cols.forEach((col, ci) => {
    col.forEach((item, i) => {
      const y = startY + i * 0.52;
      s.addShape(pres.ShapeType.roundRect, {
        x: xs[ci], y, w: 4.5, h: 0.44,
        fill: { color: i % 2 === 0 ? "0F3558" : "122E48" },
        line: { color: C.teal, width: 0.5 },
        rectRadius: 0.05
      });
      s.addShape(pres.ShapeType.roundRect, {
        x: xs[ci], y, w: 0.44, h: 0.44,
        fill: { color: C.teal },
        rectRadius: 0.05
      });
      s.addText(item[0], {
        x: xs[ci], y, w: 0.44, h: 0.44, fontSize: 10, bold: true,
        color: C.white, align: "center", valign: "middle"
      });
      s.addText(item[1], {
        x: xs[ci] + 0.5, y, w: 3.9, h: 0.44, fontSize: 10.5,
        color: "C8DCE8", valign: "middle"
      });
    });
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 3 – INTRODUCTION & OVERVIEW
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 1 – INTRODUCTION");

  s.addText("Introduction & Overview", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 4, C.rose);

  card(s, 0.3, 1.4, 9.4, 1.4, C.lightTeal);
  s.addText("The breast (mamma) is a modified tubuloalveolar apocrine sweat gland that forms part of the reproductive system in females. It lies in the superficial fascia of the anterior thoracic wall. Each breast consists of mammary glands together with associated connective tissue, fat, overlying skin, a nipple, and an areola.", {
    x: 0.5, y: 1.5, w: 9.1, h: 1.2, fontSize: 13, color: C.darkText, valign: "top"
  });

  sectionHeading(s, "Key Facts", 0.3, 2.95, 4.5);

  const facts = [
    "Paired organs on the anterior thoracic wall",
    "Derived embryologically from modified sweat glands (ectoderm)",
    "Functional role: produce milk (lactation) for newborn nourishment",
    "Respond to a complex interplay of hormones across a female's lifespan",
    "Both males and females have rudimentary mammary glands",
  ];
  bullets(s, facts, 0.3, 3.5, 4.5, 1.8, { fontSize: 12 });

  sectionHeading(s, "Developmental Origin", 5.1, 2.95, 4.5, C.rose);
  const dev = [
    "Arise from milk lines (ectodermal ridges) extending axilla to perineum",
    "Supernumerary nipples / breasts arise from persistence of these ridges",
    "Rudimentary at birth; undergo dramatic change at puberty",
    "Complete morphological maturation occurs only during pregnancy",
  ];
  bullets(s, dev, 5.1, 3.5, 4.5, 1.8, { fontSize: 12 });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 4 – GROSS ANATOMY
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 2 – GROSS ANATOMY");

  s.addText("Position & Extent", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 3.5, C.teal);

  // Left column
  sectionHeading(s, "Surface Landmarks", 0.3, 1.35, 4.5);
  const landmarks = [
    "Lies on deep fascia of pectoralis major muscle",
    "Extends vertically: rib II to rib VI",
    "Extends horizontally: sternum to midaxillary line",
    "Separated from deep fascia by retromammary space (loose connective tissue) – allows movement",
    "Axillary tail of Spence: projection into axillary fossa",
  ];
  bullets(s, landmarks, 0.3, 1.9, 4.5, 2.3, { fontSize: 12 });

  sectionHeading(s, "Structural Layers (Superficial to Deep)", 0.3, 4.3, 4.5);
  const layers = [
    "Skin (with Montgomery tubercles near areola)",
    "Subcutaneous fat",
    "Glandular parenchyma (lobes/lobules/ducts)",
    "Suspensory ligaments (Cooper's)",
    "Retromammary space",
    "Deep fascia over pectoralis major",
  ];
  bullets(s, layers, 0.3, 4.7, 4.5, 0.85, { fontSize: 11 });

  // Right column
  card(s, 5.1, 1.35, 4.6, 2.5, "EDF5F7");
  sectionHeading(s, "Relations", 5.2, 1.4, 4.3, C.rose);
  const rels = [
    "Anterior: skin, superficial fascia",
    "Posterior: pectoralis major, serratus anterior, external oblique, upper rectus abdominis",
    "Medial: sternum and costal cartilages",
    "Lateral: axillary vessels and nerves",
    "Superior: clavicle (2nd rib level)",
    "Inferior: 6th rib/anterior abdominal wall",
  ];
  bullets(s, rels, 5.2, 1.95, 4.3, 1.8, { fontSize: 11.5 });

  card(s, 5.1, 3.95, 4.6, 1.55, "EDF5F7");
  sectionHeading(s, "Retromammary Space", 5.2, 4.0, 4.3, C.rose);
  s.addText("The retromammary space is a layer of loose areolar connective tissue between the posterior surface of the breast and the deep fascia of pectoralis major. It allows the breast to slide on the chest wall. Obliteration of this space (by deep tumor invasion) restricts mobility and is a clinical sign.", {
    x: 5.2, y: 4.55, w: 4.2, h: 0.9, fontSize: 11, color: C.darkText
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 5 – NIPPLE & AREOLA
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 3 – EXTERNAL FEATURES");
  s.addText("Nipple & Areola Complex (NAC)", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 5, C.rose);

  // Three cards in a row
  const cards = [
    {
      title: "NIPPLE", color: C.rose,
      points: [
        "Conical protrusion at centre of areola",
        "Situated at 4th intercostal space (in nulliparous women)",
        "Contains 15–20 lactiferous duct orifices",
        "Lined by keratinising squamous epithelium near surface",
        "Smooth muscle fibres cause erection in response to stimulation",
        "Innervated mainly by T4 intercostal nerve",
      ]
    },
    {
      title: "AREOLA", color: C.teal,
      points: [
        "Circular, pigmented skin surrounding nipple",
        "Darkens during pregnancy",
        "Contains sebaceous glands (Montgomery tubercles/glands)",
        "Montgomery tubercles: 10–15 small nodules visible on surface",
        "Secrete sebum to lubricate nipple during breastfeeding",
        "Sympathetic innervation mediates pigmentation changes",
      ]
    },
    {
      title: "CLINICAL NOTES", color: C.navy,
      points: [
        "Congenital nipple inversion: failure to evert during development",
        "Acquired inversion may signal subareolar carcinoma",
        "Paget's disease: intraepidermal carcinoma of nipple skin",
        "Bloody nipple discharge: consider intraductal papilloma",
        "NAC preservation in nipple-sparing mastectomy preserves identity",
        "Cooper stated up to 22 ducts but <12 typically patent",
      ]
    },
  ];
  cards.forEach((c, i) => {
    const x = 0.25 + i * 3.22;
    s.addShape(pres.ShapeType.roundRect, { x, y: 1.4, w: 3.1, h: 3.9, fill: { color: "F0F8FA" }, line: { color: c.color, width: 1.5 }, rectRadius: 0.1 });
    s.addShape(pres.ShapeType.roundRect, { x, y: 1.4, w: 3.1, h: 0.45, fill: { color: c.color }, line: { color: c.color, width: 0 }, rectRadius: 0.1 });
    s.addText(c.title, { x, y: 1.4, w: 3.1, h: 0.45, fontSize: 11, bold: true, color: C.white, align: "center", valign: "middle" });
    bullets(s, c.points, x + 0.1, 1.9, 2.9, 3.3, { fontSize: 11 });
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 6 – INTERNAL STRUCTURE
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 4 – INTERNAL STRUCTURE");
  s.addText("Lobes, Lobules & Ductal System", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 5, C.teal);

  // Summary box
  card(s, 0.3, 1.35, 9.4, 0.9, "E3F2F5");
  s.addText("The mammary gland is composed of 15–20 lobes arranged radially around the nipple. Each lobe drains via a single lactiferous duct into the nipple. These lobes are subdivided into lobules, the functional secretory units.", {
    x: 0.5, y: 1.42, w: 9.1, h: 0.76, fontSize: 12.5, color: C.darkText, valign: "middle"
  });

  const levels = [
    { num: "1", name: "LOBE", color: C.navy, desc: "15–20 lobes per breast, each separated by fibrous septa. Each lobe drains via one lactiferous duct that opens independently at the nipple." },
    { num: "2", name: "LACTIFEROUS DUCT", color: C.teal, desc: "Each lobe's duct dilates beneath the areola forming a lactiferous sinus (ampulla) that stores milk. Duct narrows again before the nipple orifice." },
    { num: "3", name: "SEGMENTAL & SUBSEGMENTAL DUCTS", color: "2A6E7A", desc: "Progressively branch within each lobe, ultimately leading to terminal ductules." },
    { num: "4", name: "TERMINAL DUCT LOBULAR UNIT (TDLU)", color: C.rose, desc: "The functional unit: a terminal intralobular duct with its cluster of acini (alveoli). Site of origin of most breast carcinomas. Surrounded by specialised intralobular stroma." },
    { num: "5", name: "ACINUS (ALVEOLUS)", color: "A0303F", desc: "Blind-ending sac lined by secretory (luminal) epithelial cells and outer myoepithelial cells. Produces milk during lactation." },
  ];
  levels.forEach((lv, i) => {
    const y = 2.35 + i * 0.62;
    s.addShape(pres.ShapeType.roundRect, { x: 0.3, y, w: 0.5, h: 0.5, fill: { color: lv.color }, rectRadius: 0.08 });
    s.addText(lv.num, { x: 0.3, y, w: 0.5, h: 0.5, fontSize: 16, bold: true, color: C.white, align: "center", valign: "middle" });
    s.addText(lv.name + ":", { x: 0.88, y: y + 0.03, w: 2.2, h: 0.44, fontSize: 11.5, bold: true, color: lv.color, valign: "middle" });
    s.addText(lv.desc, { x: 3.1, y: y + 0.03, w: 6.6, h: 0.44, fontSize: 11, color: C.darkText, valign: "middle" });
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 7 – COOPER'S LIGAMENTS
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 5 – SUPPORTING STRUCTURES");
  s.addText("Suspensory Ligaments of Cooper", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 5.5, C.rose);

  card(s, 0.3, 1.38, 9.4, 0.8, C.lightTeal);
  s.addText("Cooper's ligaments (suspensory ligaments of the breast) are well-defined fibrous bands of connective tissue that pass from the skin of the breast through its substance to attach to the overlying dermis and the deep fascia covering pectoralis major, providing structural support.", {
    x: 0.5, y: 1.44, w: 9.1, h: 0.68, fontSize: 12.5, color: C.darkText, valign: "middle"
  });

  sectionHeading(s, "Structure & Function", 0.3, 2.28, 4.5);
  const struct = [
    "Fibrous extensions of interlobular stroma",
    "Run from skin dermis to deep fascia (pectoralis major)",
    "Divide the breast into compartments (lobes)",
    "Provide structural support and shape to the breast",
    "Continuous with the septa that separate lobes",
    "Allow some mobility of breast over chest wall",
  ];
  bullets(s, struct, 0.3, 2.82, 4.5, 2.0, { fontSize: 12 });

  sectionHeading(s, "Clinical Significance", 5.1, 2.28, 4.6, C.rose);
  const clin = [
    "Breast carcinoma infiltrating ligaments causes skin dimpling (peau d'orange sign when lymphatics also blocked)",
    "Pitting: carcinoma creates tension on these ligaments, drawing skin inward",
    "Loss of ligament integrity: breast ptosis (sagging) with age / post-lactation",
    "Cooper's ligaments are used in plastic surgery as anchor points for mastopexy",
    "Ultrasound: hyperechoic bands traversing breast parenchyma",
  ];
  bullets(s, clin, 5.1, 2.82, 4.6, 2.0, { fontSize: 12 });

  // bottom note
  s.addShape(pres.ShapeType.rect, { x: 0.3, y: 4.88, w: 9.4, h: 0.55, fill: { color: C.navy } });
  s.addText("Named after Sir Astley Cooper (1768–1841) who first described them in 'On the Anatomy of the Breast' (1840)", {
    x: 0.5, y: 4.88, w: 9.2, h: 0.55, fontSize: 11, color: "A8C8D0", align: "center", valign: "middle", italic: true
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 8 – ARTERIAL SUPPLY
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 6 – VASCULAR SUPPLY");
  s.addText("Arterial Supply of the Breast", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 5, C.teal);

  const arteries = [
    {
      source: "Internal Thoracic Artery\n(Internal Mammary Artery)",
      detail: "Perforating branches from 2nd–4th intercostal spaces supply the ANTEROMEDIAL breast (50–60% of total supply). A major vessel in surgical planning.",
      color: C.rose
    },
    {
      source: "Lateral Thoracic Artery\n(branch of axillary artery)",
      detail: "Supplies the LATERAL and central breast. External mammary branches are the main lateral supply.",
      color: C.teal
    },
    {
      source: "Thoracoacromial Artery\n(pectoral branch)",
      detail: "Pectoral branch runs behind pectoralis minor and perforates to supply superolateral breast.",
      color: C.navy
    },
    {
      source: "Posterior Intercostal Arteries\n(2nd–4th)",
      detail: "Lateral cutaneous branches contribute to breast supply via perforators through intercostal spaces.",
      color: "2A6E7A"
    },
    {
      source: "Subscapular Artery\n(branch of axillary artery)",
      detail: "Minor contribution. Relevant in flap-based reconstruction (latissimus dorsi flap is based on thoracodorsal branch).",
      color: "5A3060"
    },
  ];

  arteries.forEach((a, i) => {
    const y = 1.38 + i * 0.83;
    s.addShape(pres.ShapeType.roundRect, { x: 0.3, y, w: 9.4, h: 0.76, fill: { color: i % 2 === 0 ? "EAF4F6" : "F4F4EF" }, line: { color: a.color, width: 1.2 }, rectRadius: 0.07 });
    s.addShape(pres.ShapeType.roundRect, { x: 0.3, y, w: 3.1, h: 0.76, fill: { color: a.color }, line: { color: a.color, width: 0 }, rectRadius: 0.07 });
    s.addText(a.source, { x: 0.35, y, w: 3.0, h: 0.76, fontSize: 11, bold: true, color: C.white, align: "center", valign: "middle" });
    s.addText(a.detail, { x: 3.55, y: y + 0.05, w: 6.0, h: 0.68, fontSize: 11.5, color: C.darkText, valign: "middle" });
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 9 – VENOUS & LYMPHATIC DRAINAGE
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTIONS 7 & 8 – DRAINAGE");
  s.addText("Venous & Lymphatic Drainage", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 6, C.rose);

  // Venous (left)
  sectionHeading(s, "Venous Drainage", 0.3, 1.35, 4.5);
  card(s, 0.3, 1.88, 4.5, 2.55, "EDF5F7");
  s.addText("Veins parallel the arteries and drain into three main trunks:", {
    x: 0.45, y: 1.96, w: 4.2, h: 0.44, fontSize: 12, bold: true, color: C.navy
  });
  const veins = [
    ["Axillary vein", "via lateral thoracic and subscapular veins"],
    ["Internal thoracic vein", "drains anteromedial tributaries"],
    ["Intercostal veins", "connect to vertebral venous plexus (Batson's plexus) – CLINICALLY IMPORTANT: hematogenous spread of breast cancer to vertebrae"],
  ];
  veins.forEach(([v, d], i) => {
    s.addShape(pres.ShapeType.ellipse, { x: 0.38, y: 2.45 + i * 0.65, w: 0.15, h: 0.15, fill: { color: C.rose } });
    s.addText(v + ":", { x: 0.58, y: 2.42 + i * 0.65, w: 1.8, h: 0.5, fontSize: 11.5, bold: true, color: C.rose, valign: "middle" });
    s.addText(d, { x: 0.58, y: 2.57 + i * 0.65, w: 4.0, h: 0.55, fontSize: 11, color: C.darkText });
  });

  // Lymphatic (right)
  sectionHeading(s, "Lymphatic Drainage", 5.0, 1.35, 4.7, C.teal);
  card(s, 5.0, 1.88, 4.7, 2.55, "EDF5F7");

  const lymph = [
    { pct: "~75%", dest: "Axillary nodes", detail: "Main pathway. Lateral superior drainage. Nodes: pectoral, subscapular, humeral, central, apical.", color: C.teal },
    { pct: "~20%", dest: "Parasternal nodes", detail: "Internal thoracic chain; medial breast. Drains to bronchomediastinal trunk.", color: C.navy },
    { pct: "~5%", dest: "Interpectoral / other", detail: "Via Rotter's nodes between pectoralis muscles; posterior intercostal nodes; subdiaphragmatic.", color: C.rose },
  ];
  lymph.forEach((l, i) => {
    const y = 1.98 + i * 0.82;
    s.addShape(pres.ShapeType.roundRect, { x: 5.1, y, w: 4.5, h: 0.72, fill: { color: C.white }, line: { color: l.color, width: 1 }, rectRadius: 0.06 });
    s.addShape(pres.ShapeType.roundRect, { x: 5.1, y, w: 0.8, h: 0.72, fill: { color: l.color }, rectRadius: 0.06 });
    s.addText(l.pct, { x: 5.1, y, w: 0.8, h: 0.72, fontSize: 11, bold: true, color: C.white, align: "center", valign: "middle" });
    s.addText(l.dest + "\n" + l.detail, { x: 6.0, y: y + 0.05, w: 3.5, h: 0.62, fontSize: 10.5, color: C.darkText });
  });

  // Bottom note
  s.addShape(pres.ShapeType.rect, { x: 0.3, y: 4.52, w: 9.4, h: 0.88, fill: { color: C.navy } });
  s.addText("Sentinel Lymph Node: The first axillary node to receive lymph from the breast tumour. Identified by blue dye or radiotracer injection and biopsied before full axillary clearance in staging.", {
    x: 0.5, y: 4.55, w: 9.2, h: 0.82, fontSize: 11.5, color: "A8C8D0", valign: "middle", italic: true
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 10 – INNERVATION
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 9 – INNERVATION");
  s.addText("Nerve Supply of the Breast", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 4, C.teal);

  card(s, 0.3, 1.38, 9.4, 0.72, C.lightTeal);
  s.addText("The breast receives somatic sensory innervation from intercostal nerves (T2–T6) via their anterior and lateral cutaneous branches. Autonomic (sympathetic) fibres accompany the arteries and control glandular secretion and smooth muscle in nipple and blood vessels.", {
    x: 0.5, y: 1.43, w: 9.1, h: 0.62, fontSize: 12.5, color: C.darkText, valign: "middle"
  });

  const nerves = [
    { n: "T2–T6 Intercostal Nerves", type: "Sensory", detail: "Anterior and lateral cutaneous branches provide sensation to the breast skin. The supraclavicular nerves (C3/C4) innervate the upper breast skin.", color: C.teal },
    { n: "4th Intercostal Nerve (T4)", type: "Key nerve", detail: "Primary innervation of the nipple-areola complex. Essential to preserve in mastectomy / breast reduction to maintain nipple sensation.", color: C.rose },
    { n: "Medial Pectoral Nerve", type: "Motor", detail: "Innervates pectoralis minor and part of pectoralis major. At risk in axillary dissection.", color: C.navy },
    { n: "Long Thoracic Nerve (C5–C7)", type: "Motor", detail: "Innervates serratus anterior. Injury during axillary surgery causes 'winged scapula'.", color: "5A3060" },
    { n: "Thoracodorsal Nerve (C6–C8)", type: "Motor", detail: "Innervates latissimus dorsi. Injury during axillary dissection causes weakness in adduction and extension.", color: "2A6E7A" },
    { n: "Intercostobrachial Nerve (T2)", type: "Sensory", detail: "Lateral cutaneous branch of T2; crosses axilla to supply medial upper arm skin. Often cut in axillary clearance causing altered sensation.", color: "7A4020" },
  ];

  nerves.forEach((nv, i) => {
    const col = i < 3 ? 0 : 1;
    const row = i % 3;
    const x = col === 0 ? 0.3 : 5.1;
    const y = 2.22 + row * 1.05;
    s.addShape(pres.ShapeType.roundRect, { x, y, w: 4.6, h: 0.92, fill: { color: "EAF4F6" }, line: { color: nv.color, width: 1.2 }, rectRadius: 0.07 });
    s.addText(nv.n, { x: x + 0.1, y, w: 4.4, h: 0.35, fontSize: 12, bold: true, color: nv.color, valign: "bottom" });
    s.addText("[" + nv.type + "] " + nv.detail, { x: x + 0.1, y: y + 0.35, w: 4.4, h: 0.55, fontSize: 10.5, color: C.darkText, valign: "top" });
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 11 – HISTOLOGY OVERVIEW
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 10 – HISTOLOGY: CELL TYPES");
  s.addText("Histology – Overview of Cell Types", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 5, C.rose);

  card(s, 0.3, 1.36, 9.4, 0.72, C.lightTeal);
  s.addText("The cellular constituents of the breast include two major structures (ducts and lobules), two types of epithelial cells (luminal and myoepithelial), and two types of stromal cells (interlobular and intralobular). Each element is a source of both benign and malignant lesions.   — Robbins, Cotran & Kumar Pathologic Basis of Disease", {
    x: 0.5, y: 1.4, w: 9.1, h: 0.62, fontSize: 12, color: C.darkText, italic: true, valign: "middle"
  });

  const cells = [
    {
      title: "LUMINAL EPITHELIAL CELLS",
      color: C.rose,
      points: [
        "Line the inner surface of ducts and acini",
        "Columnar to cuboidal shape",
        "Produce milk proteins and fat during lactation",
        "Express oestrogen and progesterone receptors (ER/PR)",
        "Express cytokeratins 8 & 18",
        "Site of origin of most breast carcinomas",
      ]
    },
    {
      title: "MYOEPITHELIAL CELLS",
      color: C.teal,
      points: [
        "Basally located between luminal cells and basement membrane",
        "Contractile – aid milk ejection via oxytocin response",
        "Support and maintain basement membrane integrity",
        "Express cytokeratins 5/6, 14; also p63, SMA (smooth muscle actin)",
        "Absent in invasive carcinoma (important diagnostic marker)",
        "Act as 'tumour suppressors' – inhibit invasion",
      ]
    },
    {
      title: "STROMAL CELLS",
      color: C.navy,
      points: [
        "Intralobular stroma: loose, hormone-sensitive; surrounds TDLU",
        "Interlobular stroma: dense fibrous/collagenous; between lobes",
        "Fibroblasts maintain extracellular matrix",
        "Adipocytes: predominant in non-lactating adult breast",
        "Endothelial cells (capillaries) & pericytes",
        "Scattered inflammatory cells in normal breast",
      ]
    },
  ];
  cells.forEach((c, i) => {
    const x = 0.25 + i * 3.22;
    s.addShape(pres.ShapeType.roundRect, { x, y: 2.2, w: 3.1, h: 3.2, fill: { color: "F0F8FA" }, line: { color: c.color, width: 1.5 }, rectRadius: 0.1 });
    s.addShape(pres.ShapeType.roundRect, { x, y: 2.2, w: 3.1, h: 0.45, fill: { color: c.color }, line: { color: c.color, width: 0 }, rectRadius: 0.1 });
    s.addText(c.title, { x, y: 2.2, w: 3.1, h: 0.45, fontSize: 9.5, bold: true, color: C.white, align: "center", valign: "middle", charSpacing: 1 });
    bullets(s, c.points, x + 0.1, 2.7, 2.9, 2.65, { fontSize: 11 });
  });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 12 – TDLU
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 11 – HISTOLOGY: TDLU");
  s.addText("Terminal Duct Lobular Unit (TDLU)", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 6, C.teal);

  // Definition card
  card(s, 0.3, 1.38, 9.4, 0.86, "E3F2F5");
  s.addText("The TDLU is the fundamental morphological and functional unit of the breast. It comprises a terminal intralobular duct and the cluster of acini (alveoli) that bud from it, all surrounded by specialised hormone-responsive intralobular stroma. The TDLU is the site of origin of the vast majority of breast pathologies.", {
    x: 0.5, y: 1.43, w: 9.1, h: 0.76, fontSize: 12.5, color: C.darkText, valign: "middle"
  });

  sectionHeading(s, "TDLU Components", 0.3, 2.38, 4.6);
  const comp = [
    "Terminal intralobular duct: connects the lobule to the subsegmental duct system",
    "Acini (alveoli): blind-ending secretory sacs, 10–100 per lobule",
    "Intralobular stroma: loose connective tissue, rich in cells, hormone-sensitive",
    "Basement membrane: surrounds the entire ductal-lobular system",
    "Capillary network: dense within intralobular stroma",
  ];
  bullets(s, comp, 0.3, 2.92, 4.6, 2.35, { fontSize: 12 });

  sectionHeading(s, "Histological Appearance", 5.1, 2.38, 4.6, C.rose);
  const hist = [
    "H&E: lobule appears as cluster of small round acini embedded in loose pale stroma, distinct from the denser interlobular stroma",
    "Acini: lined by inner columnar luminal cells (pale cytoplasm) and outer flat myoepithelial cells",
    "Basement membrane: PAS positive; not visible on routine H&E but seen with Reticulin/PAS stains",
    "Intralobular stroma: loose, oedematous, pink on H&E; more cellular than interlobular stroma",
    "IHC: luminal cells CK8/18+; myoepithelial cells p63+, SMA+, CK5/6+",
  ];
  bullets(s, hist, 5.1, 2.92, 4.6, 2.35, { fontSize: 12 });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 13 – DUCTAL SYSTEM & NIPPLE HISTOLOGY
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 12 – HISTOLOGY: DUCTAL SYSTEM");
  s.addText("Ductal System & Nipple Histology", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 5.5, C.rose);

  const ductLevels = [
    {
      name: "Nipple Surface / Lactiferous Sinus",
      lining: "Keratinising stratified squamous epithelium at surface; transitions to non-keratinising squamous near orifice",
      other: "Contains smooth muscle fibres, sebaceous glands; Montgomery tubercles are visible at areola surface",
      color: C.navy
    },
    {
      name: "Main Lactiferous Ducts (2–4 mm diameter)",
      lining: "Double-layered: inner columnar/cuboidal luminal cells + outer myoepithelial cells",
      other: "Surrounded by elastic fibres; subareolar region may have lactiferous sinus (ampulla) storing milk",
      color: C.rose
    },
    {
      name: "Segmental & Subsegmental Ducts",
      lining: "Two-layered epithelium becomes progressively more cuboidal; myoepithelial layer remains present",
      other: "Surrounded by dense interlobular collagenous stroma; elastic fibres present around larger ducts",
      color: C.teal
    },
    {
      name: "Terminal Intralobular Duct & Acini",
      lining: "Cuboidal luminal cells (may show secretory vacuoles in luteal phase); myoepithelial cells persist",
      other: "Surrounded by loose intralobular stroma; basement membrane present throughout; IHC identifies cell layers",
      color: "2A8070"
    },
  ];

  ductLevels.forEach((d, i) => {
    const y = 1.36 + i * 1.02;
    s.addShape(pres.ShapeType.roundRect, { x: 0.3, y, w: 9.4, h: 0.9, fill: { color: i % 2 === 0 ? "EAF5F6" : "F5F0EA" }, line: { color: d.color, width: 1.2 }, rectRadius: 0.07 });
    s.addShape(pres.ShapeType.roundRect, { x: 0.3, y, w: 2.5, h: 0.9, fill: { color: d.color }, rectRadius: 0.07 });
    s.addText(d.name, { x: 0.35, y, w: 2.4, h: 0.9, fontSize: 11, bold: true, color: C.white, align: "center", valign: "middle" });
    s.addText("Lining: " + d.lining, { x: 2.9, y: y + 0.03, w: 6.7, h: 0.4, fontSize: 11, color: C.darkText });
    s.addText("Note: " + d.other, { x: 2.9, y: y + 0.46, w: 6.7, h: 0.4, fontSize: 10.5, color: C.midText, italic: true });
  });

  s.addShape(pres.ShapeType.rect, { x: 0.3, y: 5.48, w: 9.4, h: 0.02, fill: { color: C.teal } });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 14 – STROMA
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 13 – HISTOLOGY: STROMA");
  s.addText("Stromal Components", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 4, C.teal);

  // Two stroma types
  const stromaTypes = [
    {
      title: "INTRALOBULAR STROMA",
      color: C.teal,
      desc: "Specialised, loose, myxoid connective tissue that immediately surrounds the acini and terminal ductules within each TDLU.",
      points: [
        "Rich in fibroblasts, myofibroblasts, and proteoglycans",
        "Highly hormone-responsive (oestrogen, progesterone)",
        "Expands during proliferative phase of menstrual cycle",
        "Source of fibroadenomas (when fibroblasts overgrow)",
        "Dense capillary network within it",
        "Loosely structured – appears pale blue/grey on H&E",
      ]
    },
    {
      title: "INTERLOBULAR STROMA",
      color: C.rose,
      desc: "Dense fibro-collagenous tissue that forms the bulk of the non-glandular breast. Separates the lobes and lobules from one another.",
      points: [
        "Predominantly collagen (type I) and elastic fibres",
        "Abundant adipose tissue (main determinant of breast size in non-pregnant women)",
        "Less cellular than intralobular stroma",
        "Involutes progressively after 3rd decade – replaced by fat",
        "Source of phyllodes tumour (stromal overgrowth > fibroadenoma)",
        "Radiologically dense in young women (fibroglandular density on mammogram)",
      ]
    },
  ];
  stromaTypes.forEach((st, i) => {
    const x = i === 0 ? 0.3 : 5.1;
    s.addShape(pres.ShapeType.roundRect, { x, y: 1.38, w: 4.5, h: 3.95, fill: { color: "EAF5F6" }, line: { color: st.color, width: 1.5 }, rectRadius: 0.08 });
    s.addShape(pres.ShapeType.roundRect, { x, y: 1.38, w: 4.5, h: 0.44, fill: { color: st.color }, line: { color: st.color, width: 0 }, rectRadius: 0.08 });
    s.addText(st.title, { x, y: 1.38, w: 4.5, h: 0.44, fontSize: 12, bold: true, color: C.white, align: "center", valign: "middle", charSpacing: 1 });
    s.addText(st.desc, { x: x + 0.15, y: 1.88, w: 4.2, h: 0.72, fontSize: 11.5, color: C.midText, italic: true });
    bullets(s, st.points, x + 0.15, 2.65, 4.2, 2.6, { fontSize: 11.5 });
  });

  // Bottom note
  s.addShape(pres.ShapeType.rect, { x: 0.3, y: 5.38, w: 9.4, h: 0.1, fill: { color: C.rose } });
}

// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 15 – PHYSIOLOGICAL CHANGES
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.cream);
  titleBar(s, "SECTION 14 – PHYSIOLOGICAL CHANGES");
  s.addText("Dynamic Changes Across the Lifespan", {
    x: 0.4, y: 0.65, w: 9.2, h: 0.55, fontSize: 24, bold: true, color: C.navy
  });
  accentLine(s, 0.4, 1.25, 7, C.rose);

  const phases = [
    {
      phase: "PUBERTY", years: "(age ~10–16)", color: C.teal,
      points: [
        "Oestrogen stimulates ductal elongation and branching",
        "Progesterone promotes lobule/alveolar development",
        "Interlobular stroma and fat increase (breast growth)",
        "Nipple and areola enlarge and become pigmented",
      ]
    },
    {
      phase: "MENSTRUAL CYCLE", years: "(monthly)", color: C.rose,
      points: [
        "Follicular phase: lobules relatively quiescent",
        "Luteal phase: oestrogen/progesterone cause epithelial proliferation, secretory activity, and increased acini/lobule",
        "Menstruation: fall in hormones → partial lobular regression",
        "Cyclic mastalgia: oedema and swelling common in luteal phase",
      ]
    },
    {
      phase: "PREGNANCY", years: "(full maturation)", color: C.navy,
      points: [
        "Lobules increase progressively in number and size",
        "Breast composed almost entirely of lobules at term",
        "Hormones: oestrogen, progesterone, prolactin (pituitary), hPL, gonadocorticoids",
        "Initially colostrum (high protein) → milk (higher fat/calories) at day 3–10 postpartum",
      ]
    },
    {
      phase: "INVOLUTION", years: "(post-30s / menopause)", color: "5A3060",
      points: [
        "Lobules and specialised stroma progressively involute (pre-menopause)",
        "Interlobular stroma converts from dense fibrous → radiolucent adipose",
        "Mammographic density decreases (fatty replacement)",
        "At menopause: further glandular regression, fat replaces parenchyma",
      ]
    },
  ];

  phases.forEach((ph, i) => {
    const col = i % 2;
    const row = Math.floor(i / 2);
    const x = col === 0 ? 0.3 : 5.1;
    const y = 1.4 + row * 2.1;
    s.addShape(pres.ShapeType.roundRect, { x, y, w: 4.5, h: 1.9, fill: { color: "F0F8FA" }, line: { color: ph.color, width: 1.5 }, rectRadius: 0.08 });
    s.addShape(pres.ShapeType.roundRect, { x, y, w: 4.5, h: 0.42, fill: { color: ph.color }, line: { color: ph.color, width: 0 }, rectRadius: 0.08 });
    s.addText(ph.phase + "  " + ph.years, { x, y, w: 4.5, h: 0.42, fontSize: 11, bold: true, color: C.white, align: "center", valign: "middle" });
    bullets(s, ph.points, x + 0.1, y + 0.48, 4.3, 1.38, { fontSize: 11 });
  });
}

// Slide 16 – LACTATION
// (Counts as slide 15 content continuation – relabel as summary/clinical)
// ═══════════════════════════════════════════════════════════════════════════
// SLIDE 16 (last) – SUMMARY & CLINICAL CORRELATIONS
// ═══════════════════════════════════════════════════════════════════════════
{
  const s = addSlide(C.navy);
  // accent bar
  s.addShape(pres.ShapeType.rect, { x: 0, y: 0, w: 10, h: 0.08, fill: { color: C.rose } });
  s.addShape(pres.ShapeType.rect, { x: 0, y: 5.545, w: 10, h: 0.08, fill: { color: C.rose } });

  s.addText("Summary & Clinical Correlations", {
    x: 0.5, y: 0.2, w: 9, h: 0.62, fontSize: 26, bold: true,
    color: C.white, align: "center"
  });
  accentLine(s, 2, 0.88, 6, C.teal);

  const rows = [
    {
      heading: "ANATOMY KEY POINTS",
      color: C.teal,
      items: [
        "15–20 lobes drain individually at nipple via lactiferous ducts",
        "Retromammary space allows breast mobility (obliterated by deep carcinoma)",
        "75% lymph to axillary nodes; 20% to parasternal nodes",
        "T4 nerve innervates nipple-areola (at risk in surgery)",
      ]
    },
    {
      heading: "HISTOLOGY KEY POINTS",
      color: C.rose,
      items: [
        "TDLU = functional unit; origin of most breast carcinomas",
        "Dual cell layer: luminal (CK8/18+, ER+) + myoepithelial (p63+, SMA+)",
        "Myoepithelial layer absent in invasive carcinoma",
        "Intralobular stroma is hormone-responsive; interlobular stroma is fibrous/fatty",
      ]
    },
    {
      heading: "CLINICAL CORRELATIONS",
      color: "A0B830",
      items: [
        "Skin dimpling = Cooper's ligament involvement by carcinoma",
        "Winged scapula = long thoracic nerve injury in axillary surgery",
        "Batson's plexus = vertebral metastasis route via intercostal veins",
        "Mammographic density correlates with fibroglandular stroma (risk factor for cancer)",
      ]
    },
  ];

  rows.forEach((r, i) => {
    const y = 1.0 + i * 1.52;
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    s.addText(r.heading, { x: 0.45, y, w: 2.3, h: 1.4, fontSize: 11, bold: true, color: C.white, align: "center", valign: "middle", charSpacing: 1 });
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  s.addText("Gray's Anatomy for Students (9780323934237)  |  Robbins & Kumar Basic Pathology (9780323790185)  |  Robbins, Cotran & Kumar (9780443264528)  |  Histology A Text and Atlas (9781975181512)", {
    x: 0.4, y: 5.33, w: 9.2, h: 0.22, fontSize: 7.5, color: "506080", align: "center"
  });
}

// ── WRITE FILE ────────────────────────────────────────────────────────────
pres.writeFile({ fileName: "/home/daytona/workspace/breast-anatomy-ppt/Normal_Breast_Anatomy_Histology.pptx" })
  .then(() => console.log("Done: Normal_Breast_Anatomy_Histology.pptx"))
  .catch(e => { console.error(e); process.exit(1); });