const pptxgen = require("pptxgenjs");

const pres = new pptxgen();
pres.layout = "LAYOUT_16x9";
pres.title = "Muscle Tone";
pres.author = "Medical Education";

// ─── Color Palette ───────────────────────────────────────────────────────────
const DARK_BG   = "0D1B2A";   // deep navy (dominant dark)
const MID_BG    = "1B3A5C";   // steel blue
const ACCENT    = "2ECC71";   // vivid green (accent)
const ACCENT2   = "F39C12";   // amber (secondary accent)
const LIGHT_TXT = "FFFFFF";
const SOFT_TXT  = "BFD7ED";
const DARK_TXT  = "0D1B2A";
const CARD_BG   = "163350";   // card background
const DIVIDER   = "2ECC71";

// ─── Helper: slide background ────────────────────────────────────────────────
function darkSlide(pres) {
  const s = pres.addSlide();
  s.background = { color: DARK_BG };
  return s;
}
function midSlide(pres) {
  const s = pres.addSlide();
  s.background = { color: MID_BG };
  return s;
}
function lightSlide(pres) {
  const s = pres.addSlide();
  s.background = { color: "EAF2FB" };
  return s;
}

// ─── Helper: section header bar ──────────────────────────────────────────────
function addTopBar(slide, color = ACCENT) {
  slide.addShape("rect", { x: 0, y: 0, w: 10, h: 0.12, fill: { color } });
}
function addBottomBar(slide, color = ACCENT) {
  slide.addShape("rect", { x: 0, y: 5.5, w: 10, h: 0.125, fill: { color } });
}

// ─── SLIDE 1: Title Slide ────────────────────────────────────────────────────
{
  const s = darkSlide(pres);
  // Top accent bar
  s.addShape("rect", { x: 0, y: 0, w: 10, h: 0.18, fill: { color: ACCENT } });
  // Left accent bar
  s.addShape("rect", { x: 0, y: 0, w: 0.22, h: 5.625, fill: { color: ACCENT } });
  // Decorative circle
  s.addShape("ellipse", { x: 6.8, y: 1.0, w: 3.5, h: 3.5, fill: { color: MID_BG }, line: { color: ACCENT, width: 3 } });
  s.addShape("ellipse", { x: 7.1, y: 1.3, w: 2.9, h: 2.9, fill: { color: DARK_BG }, line: { color: ACCENT2, width: 1.5 } });

  // Icon area text
  s.addText("💪", { x: 7.5, y: 2.0, w: 1.8, h: 1.8, fontSize: 60, align: "center", valign: "middle" });

  // Title
  s.addText("MUSCLE TONE", {
    x: 0.5, y: 1.2, w: 6.0, h: 1.2,
    fontSize: 46, bold: true, color: LIGHT_TXT,
    fontFace: "Calibri", align: "left", charSpacing: 4
  });
  // Subtitle
  s.addText("Physiology, Neural Control & Clinical Significance", {
    x: 0.5, y: 2.55, w: 6.0, h: 0.55,
    fontSize: 16, color: ACCENT, fontFace: "Calibri", align: "left", italic: true
  });
  // Divider line
  s.addShape("rect", { x: 0.5, y: 3.2, w: 5.5, h: 0.04, fill: { color: SOFT_TXT } });
  // Tagline
  s.addText("Understanding the foundation of posture, movement & neurological assessment", {
    x: 0.5, y: 3.35, w: 6.0, h: 0.7,
    fontSize: 12, color: SOFT_TXT, fontFace: "Calibri", align: "left"
  });
  // Bottom tag
  s.addText("Medical Physiology & Neurology", {
    x: 0.5, y: 5.1, w: 4.0, h: 0.35,
    fontSize: 11, color: ACCENT2, fontFace: "Calibri", align: "left"
  });
}

// ─── SLIDE 2: Overview / Outline ─────────────────────────────────────────────
{
  const s = midSlide(pres);
  addTopBar(s);
  addBottomBar(s);

  s.addText("OVERVIEW", {
    x: 0.5, y: 0.25, w: 9, h: 0.5,
    fontSize: 11, color: ACCENT, bold: true, charSpacing: 5, fontFace: "Calibri"
  });
  s.addText("Topics Covered", {
    x: 0.5, y: 0.8, w: 9, h: 0.6,
    fontSize: 28, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  const topics = [
    ["01", "Definition & Concept of Muscle Tone"],
    ["02", "Structural Basis – Muscle Spindle & Golgi Tendon Organ"],
    ["03", "Neural Control – Alpha & Gamma Motor Neurons"],
    ["04", "Stretch Reflex & Gamma Loop"],
    ["05", "Central Nervous System Influences"],
    ["06", "Classification: Normotonia, Hypertonia, Hypotonia"],
    ["07", "Hypertonia – Spasticity"],
    ["08", "Hypertonia – Rigidity"],
    ["09", "Hypotonia – Causes & Features"],
    ["10", "Clinical Assessment of Muscle Tone"],
    ["11", "UMN vs LMN Lesions & Tone"],
    ["12", "Clasp-Knife vs Lead-Pipe Phenomenon"],
    ["13", "Clonus & Hyperreflexia"],
    ["14", "Tone in Special Conditions"],
    ["15", "Summary & Clinical Pearls"],
  ];

  // Two columns
  const col1 = topics.slice(0, 8);
  const col2 = topics.slice(8);

  col1.forEach((t, i) => {
    s.addShape("rect", { x: 0.4, y: 1.55 + i * 0.47, w: 0.38, h: 0.32, fill: { color: ACCENT }, rounding: "0.1" });
    s.addText(t[0], { x: 0.4, y: 1.55 + i * 0.47, w: 0.38, h: 0.32, fontSize: 9, bold: true, color: DARK_TXT, align: "center", valign: "middle" });
    s.addText(t[1], { x: 0.86, y: 1.56 + i * 0.47, w: 4.2, h: 0.3, fontSize: 12, color: LIGHT_TXT, fontFace: "Calibri" });
  });

  col2.forEach((t, i) => {
    s.addShape("rect", { x: 5.2, y: 1.55 + i * 0.47, w: 0.38, h: 0.32, fill: { color: ACCENT2 }, rounding: "0.1" });
    s.addText(t[0], { x: 5.2, y: 1.55 + i * 0.47, w: 0.38, h: 0.32, fontSize: 9, bold: true, color: DARK_TXT, align: "center", valign: "middle" });
    s.addText(t[1], { x: 5.66, y: 1.56 + i * 0.47, w: 4.0, h: 0.3, fontSize: 12, color: LIGHT_TXT, fontFace: "Calibri" });
  });
}

// ─── SLIDE 3: Definition ─────────────────────────────────────────────────────
{
  const s = darkSlide(pres);
  addTopBar(s);
  addBottomBar(s);

  s.addText("01 — DEFINITION", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: ACCENT, bold: true, charSpacing: 4, fontFace: "Calibri"
  });
  s.addText("Definition & Concept of Muscle Tone", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 28, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  // Big quote box
  s.addShape("rect", { x: 0.5, y: 1.4, w: 9, h: 1.2, fill: { color: CARD_BG }, line: { color: ACCENT, width: 2 } });
  s.addText('"The resistance of a muscle to passive stretch — reflecting the background level of continuous, low-grade activation maintained in skeletal muscle."', {
    x: 0.7, y: 1.5, w: 8.6, h: 1.0,
    fontSize: 15, italic: true, color: ACCENT, fontFace: "Calibri", align: "center", valign: "middle"
  });

  const points = [
    "Muscle tone is present even at rest — the muscle is never completely electrically silent",
    "It is produced by a low-frequency, asynchronous discharge of alpha motor neurons",
    "The term 'tonus' comes from Greek — meaning tension or sustained contraction",
    "Clinically tone is assessed by resistance to passive movement of a limb",
    "Normal tone keeps posture upright without conscious effort",
    "Tone differs from strength: tone = resting state; strength = voluntary contraction",
  ];

  points.forEach((p, i) => {
    s.addShape("ellipse", { x: 0.5, y: 2.78 + i * 0.44, w: 0.22, h: 0.22, fill: { color: ACCENT } });
    s.addText(p, { x: 0.82, y: 2.75 + i * 0.44, w: 8.8, h: 0.32, fontSize: 13, color: SOFT_TXT, fontFace: "Calibri" });
  });
}

// ─── SLIDE 4: Structural Basis ────────────────────────────────────────────────
{
  const s = lightSlide(pres);
  addTopBar(s, MID_BG);
  addBottomBar(s, MID_BG);

  s.addText("02 — STRUCTURAL BASIS", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: MID_BG, bold: true, charSpacing: 4, fontFace: "Calibri"
  });
  s.addText("Muscle Spindle & Golgi Tendon Organ", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 26, bold: true, color: DARK_TXT, fontFace: "Calibri"
  });

  // Left card - Muscle Spindle
  s.addShape("rect", { x: 0.3, y: 1.45, w: 4.5, h: 3.8, fill: { color: "D6EAF8" }, line: { color: MID_BG, width: 1.5 } });
  s.addShape("rect", { x: 0.3, y: 1.45, w: 4.5, h: 0.45, fill: { color: MID_BG } });
  s.addText("MUSCLE SPINDLE (Intrafusal Fiber)", {
    x: 0.4, y: 1.47, w: 4.3, h: 0.4,
    fontSize: 12, bold: true, color: LIGHT_TXT, fontFace: "Calibri", align: "center"
  });
  const spindlePoints = [
    "Specialized sensory receptor within the muscle belly",
    "Contains intrafusal muscle fibers (nuclear bag & chain)",
    "Innervated by Ia (primary) & II (secondary) afferents",
    "Detects CHANGES in muscle length (stretch)",
    "Gamma motor neurons adjust spindle sensitivity",
    "Responds to both rate of change and absolute length",
    "Activated when muscle is stretched → reflex contraction",
  ];
  spindlePoints.forEach((p, i) => {
    s.addText("• " + p, {
      x: 0.45, y: 2.0 + i * 0.43, w: 4.25, h: 0.38,
      fontSize: 11.5, color: DARK_TXT, fontFace: "Calibri"
    });
  });

  // Right card - GTO
  s.addShape("rect", { x: 5.2, y: 1.45, w: 4.5, h: 3.8, fill: { color: "FDEBD0" }, line: { color: ACCENT2, width: 1.5 } });
  s.addShape("rect", { x: 5.2, y: 1.45, w: 4.5, h: 0.45, fill: { color: ACCENT2 } });
  s.addText("GOLGI TENDON ORGAN (GTO)", {
    x: 5.3, y: 1.47, w: 4.3, h: 0.4,
    fontSize: 12, bold: true, color: DARK_TXT, fontFace: "Calibri", align: "center"
  });
  const gtoPoints = [
    "Located at the musculotendinous junction",
    "Innervated by Ib afferent fibers",
    "Detects TENSION (force) generated by contraction",
    "Triggers inhibition of agonist muscle (inverse stretch reflex)",
    "Prevents excessive force → protects tendons",
    "Activated by active contraction more than passive stretch",
    "Mediates the 'clasp-knife' relaxation phenomenon",
  ];
  gtoPoints.forEach((p, i) => {
    s.addText("• " + p, {
      x: 5.35, y: 2.0 + i * 0.43, w: 4.25, h: 0.38,
      fontSize: 11.5, color: DARK_TXT, fontFace: "Calibri"
    });
  });
}

// ─── SLIDE 5: Neural Control ──────────────────────────────────────────────────
{
  const s = darkSlide(pres);
  addTopBar(s);
  addBottomBar(s);

  s.addText("03 — NEURAL CONTROL", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: ACCENT, bold: true, charSpacing: 4, fontFace: "Calibri"
  });
  s.addText("Alpha & Gamma Motor Neurons", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 28, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  // Alpha MN card
  s.addShape("rect", { x: 0.3, y: 1.45, w: 4.5, h: 3.8, fill: { color: CARD_BG }, line: { color: ACCENT, width: 1.5 } });
  s.addShape("rect", { x: 0.3, y: 1.45, w: 4.5, h: 0.4, fill: { color: ACCENT } });
  s.addText("α (Alpha) Motor Neurons", {
    x: 0.35, y: 1.47, w: 4.4, h: 0.38,
    fontSize: 13, bold: true, color: DARK_TXT, align: "center", fontFace: "Calibri"
  });
  const alphaPts = [
    "Large myelinated neurons — fastest conduction",
    "Innervate extrafusal (working) muscle fibers",
    "Direct producers of muscle force",
    "Located in the anterior horn of spinal cord",
    "Receive inputs from: cortex, brainstem, Ia afferents, interneurons",
    "Low-frequency tonic discharge → resting muscle tone",
    "High-frequency phasic discharge → voluntary contraction",
  ];
  alphaPts.forEach((p, i) => {
    s.addText("→ " + p, {
      x: 0.45, y: 2.0 + i * 0.43, w: 4.25, h: 0.38,
      fontSize: 11.5, color: SOFT_TXT, fontFace: "Calibri"
    });
  });

  // Gamma MN card
  s.addShape("rect", { x: 5.2, y: 1.45, w: 4.5, h: 3.8, fill: { color: CARD_BG }, line: { color: ACCENT2, width: 1.5 } });
  s.addShape("rect", { x: 5.2, y: 1.45, w: 4.5, h: 0.4, fill: { color: ACCENT2 } });
  s.addText("γ (Gamma) Motor Neurons", {
    x: 5.25, y: 1.47, w: 4.4, h: 0.38,
    fontSize: 13, bold: true, color: DARK_TXT, align: "center", fontFace: "Calibri"
  });
  const gammaPts = [
    "Small neurons — slower conduction velocity",
    "Innervate intrafusal (spindle) muscle fibers",
    "Do NOT directly generate external muscle force",
    "Regulate the SENSITIVITY of muscle spindles",
    "Maintain spindle sensitivity during contraction",
    "High γ discharge → spindle taut → hyperactive reflexes",
    "Low γ discharge → spindle slack → reduced tone",
  ];
  gammaPts.forEach((p, i) => {
    s.addText("→ " + p, {
      x: 5.35, y: 2.0 + i * 0.43, w: 4.25, h: 0.38,
      fontSize: 11.5, color: SOFT_TXT, fontFace: "Calibri"
    });
  });
}

// ─── SLIDE 6: Stretch Reflex & Gamma Loop ────────────────────────────────────
{
  const s = midSlide(pres);
  addTopBar(s, ACCENT2);
  addBottomBar(s, ACCENT2);

  s.addText("04 — STRETCH REFLEX", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: ACCENT2, bold: true, charSpacing: 4, fontFace: "Calibri"
  });
  s.addText("Stretch Reflex Arc & Gamma Loop", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 28, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  // Flow boxes
  const steps = [
    { label: "STRETCH", sub: "Muscle lengthened\n(passive or active)", col: ACCENT },
    { label: "Ia AFFERENT", sub: "Spindle → spinal cord\n(monosynaptic)", col: "3498DB" },
    { label: "α MOTOR\nNEURON", sub: "Anterior horn\nactivation", col: ACCENT2 },
    { label: "MUSCLE\nCONTRACTION", sub: "Opposes\nstretch", col: "E74C3C" },
  ];

  steps.forEach((st, i) => {
    s.addShape("rect", { x: 0.35 + i * 2.4, y: 1.55, w: 2.0, h: 1.3, fill: { color: st.col }, rounding: "0.15" });
    s.addText(st.label, {
      x: 0.35 + i * 2.4, y: 1.6, w: 2.0, h: 0.55,
      fontSize: 13, bold: true, color: LIGHT_TXT, align: "center", fontFace: "Calibri"
    });
    s.addText(st.sub, {
      x: 0.35 + i * 2.4, y: 2.15, w: 2.0, h: 0.6,
      fontSize: 10, color: LIGHT_TXT, align: "center", fontFace: "Calibri"
    });
    if (i < 3) {
      s.addText("→", { x: 2.38 + i * 2.4, y: 1.85, w: 0.35, h: 0.7, fontSize: 28, color: LIGHT_TXT, align: "center", bold: true });
    }
  });

  // Gamma loop section
  s.addShape("rect", { x: 0.3, y: 3.15, w: 9.4, h: 0.4, fill: { color: DARK_BG } });
  s.addText("THE GAMMA LOOP", {
    x: 0.3, y: 3.15, w: 9.4, h: 0.4,
    fontSize: 12, bold: true, color: ACCENT2, align: "center", fontFace: "Calibri", charSpacing: 3
  });

  const gammaLoop = [
    "CNS descending signals activate γ motor neurons (co-activation with α)",
    "γ neurons contract intrafusal fibers → spindle stays taut during muscle shortening",
    "This preserves spindle sensitivity even as the whole muscle contracts",
    "Result: spindle can continue signaling stretch even mid-contraction",
    "Dysfunction of γ loop → flaccidity (low) or hypertonicity (high)",
  ];
  gammaLoop.forEach((p, i) => {
    s.addText("▸ " + p, {
      x: 0.45, y: 3.65 + i * 0.36, w: 9.1, h: 0.32,
      fontSize: 12.5, color: SOFT_TXT, fontFace: "Calibri"
    });
  });
}

// ─── SLIDE 7: CNS Influences ──────────────────────────────────────────────────
{
  const s = darkSlide(pres);
  addTopBar(s, ACCENT2);
  addBottomBar(s, ACCENT2);

  s.addText("05 — CNS INFLUENCES", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: ACCENT2, bold: true, charSpacing: 4
  });
  s.addText("Central Nervous System Control of Muscle Tone", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 26, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  const cnsData = [
    { center: "Cerebral Cortex", effect: "Inhibitory (via corticospinal tract)", detail: "Lesion → spasticity (disinhibition of stretch reflexes)" },
    { center: "Basal Ganglia", effect: "Modulates/inhibitory", detail: "Lesion → rigidity & bradykinesia (Parkinson disease)" },
    { center: "Cerebellum", effect: "Inhibitory (via Purkinje cells)", detail: "Lesion → hypotonia, ataxia, decomposition of movement" },
    { center: "Reticular Formation", effect: "Dual (pontine excites; medullary inhibits)", detail: "Reticulospinal tracts fine-tune postural tone" },
    { center: "Vestibular Nuclei", effect: "Excitatory (via vestibulospinal tract)", detail: "Maintains extensor tone for upright posture" },
    { center: "Spinal Cord", effect: "Local segmental reflex arc", detail: "Final common pathway; integrates all signals" },
  ];

  cnsData.forEach((d, i) => {
    const y = 1.45 + i * 0.68;
    s.addShape("rect", { x: 0.3, y, w: 2.5, h: 0.55, fill: { color: CARD_BG }, line: { color: ACCENT2, width: 1 } });
    s.addText(d.center, { x: 0.35, y: y + 0.05, w: 2.4, h: 0.45, fontSize: 12, bold: true, color: ACCENT2, align: "center", fontFace: "Calibri" });

    s.addShape("rect", { x: 2.9, y, w: 2.8, h: 0.55, fill: { color: CARD_BG }, line: { color: ACCENT, width: 1 } });
    s.addText(d.effect, { x: 2.95, y: y + 0.05, w: 2.7, h: 0.45, fontSize: 11, color: ACCENT, align: "center", fontFace: "Calibri" });

    s.addShape("rect", { x: 5.8, y, w: 4.1, h: 0.55, fill: { color: "112233" } });
    s.addText(d.detail, { x: 5.9, y: y + 0.05, w: 3.9, h: 0.45, fontSize: 11, color: SOFT_TXT, fontFace: "Calibri" });
  });

  // Column headers
  s.addText("CNS CENTER", { x: 0.3, y: 1.3, w: 2.5, h: 0.3, fontSize: 10, bold: true, color: ACCENT2, align: "center" });
  s.addText("NET EFFECT", { x: 2.9, y: 1.3, w: 2.8, h: 0.3, fontSize: 10, bold: true, color: ACCENT, align: "center" });
  s.addText("CLINICAL SIGNIFICANCE", { x: 5.8, y: 1.3, w: 4.1, h: 0.3, fontSize: 10, bold: true, color: SOFT_TXT, align: "center" });
}

// ─── SLIDE 8: Classification ──────────────────────────────────────────────────
{
  const s = lightSlide(pres);
  addTopBar(s, MID_BG);
  addBottomBar(s, MID_BG);

  s.addText("06 — CLASSIFICATION", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: MID_BG, bold: true, charSpacing: 4
  });
  s.addText("Types of Muscle Tone", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 28, bold: true, color: DARK_TXT, fontFace: "Calibri"
  });

  const types = [
    {
      name: "NORMOTONIA", emoji: "✅", bg: "D5F5E3", border: "27AE60",
      def: "Normal resting muscle tone",
      features: [
        "Smooth, moderate resistance to passive movement",
        "Resistance is VELOCITY-INDEPENDENT",
        "Muscle is neither floppy nor rigid",
        "Normal tendon reflexes (grade 2+)",
        "Good postural control"
      ]
    },
    {
      name: "HYPERTONIA", emoji: "⬆️", bg: "FDEBD0", border: "E67E22",
      def: "Increased resistance to passive movement",
      features: [
        "Two main types: Spasticity & Rigidity",
        "UMN or extrapyramidal lesion",
        "Enhanced stretch reflexes (hyperreflexia)",
        "May impair voluntary movement",
        "Leads to contractures if untreated"
      ]
    },
    {
      name: "HYPOTONIA", emoji: "⬇️", bg: "D6EAF8", border: "2980B9",
      def: "Decreased resistance — 'floppy' muscle",
      features: [
        "LMN lesion, cerebellar, or early UMN injury",
        "Reduced or absent tendon reflexes",
        "Muscle feels soft and doughy",
        "Joints hyperextensible passively",
        "Seen in infants — 'floppy baby' syndrome"
      ]
    },
  ];

  types.forEach((t, i) => {
    const x = 0.25 + i * 3.25;
    s.addShape("rect", { x, y: 1.5, w: 3.05, h: 3.75, fill: { color: t.bg }, line: { color: t.border, width: 2 } });
    s.addShape("rect", { x, y: 1.5, w: 3.05, h: 0.52, fill: { color: t.border } });
    s.addText(t.emoji + " " + t.name, {
      x: x + 0.05, y: 1.52, w: 2.95, h: 0.48,
      fontSize: 13, bold: true, color: LIGHT_TXT, align: "center", fontFace: "Calibri"
    });
    s.addText(t.def, {
      x: x + 0.1, y: 2.1, w: 2.85, h: 0.45,
      fontSize: 11, italic: true, color: DARK_TXT, align: "center", fontFace: "Calibri"
    });
    s.addShape("rect", { x: x + 0.1, y: 2.6, w: 2.85, h: 0.04, fill: { color: t.border } });
    t.features.forEach((f, j) => {
      s.addText("• " + f, {
        x: x + 0.1, y: 2.72 + j * 0.43, w: 2.85, h: 0.38,
        fontSize: 11, color: DARK_TXT, fontFace: "Calibri"
      });
    });
  });
}

// ─── SLIDE 9: Spasticity ──────────────────────────────────────────────────────
{
  const s = darkSlide(pres);
  addTopBar(s, "E74C3C");
  addBottomBar(s, "E74C3C");

  s.addText("07 — HYPERTONIA (I)", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: "E74C3C", bold: true, charSpacing: 4
  });
  s.addText("Spasticity", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 34, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  // Definition box
  s.addShape("rect", { x: 0.3, y: 1.4, w: 9.4, h: 0.7, fill: { color: "E74C3C" } });
  s.addText('Velocity-dependent increase in tonic stretch reflexes — due to UPPER MOTOR NEURON (corticospinal tract) lesion', {
    x: 0.5, y: 1.45, w: 9.0, h: 0.6,
    fontSize: 14, color: LIGHT_TXT, bold: true, align: "center", fontFace: "Calibri"
  });

  const spastCol1 = [
    ["Pathophysiology", "Loss of cortical inhibition → hyperactive Ia-mediated stretch reflex"],
    ["Distribution", "Upper limb: flexors dominant; Lower limb: extensors dominant"],
    ["Velocity Dependent", "Resistance INCREASES with faster passive movement"],
    ["Clasp-Knife Sign", "Initial resistance then sudden release (GTO-mediated)"],
  ];
  const spastCol2 = [
    ["Reflexes", "Hyperreflexia, clonus, Babinski sign positive"],
    ["Onset", "After spinal shock phase following acute UMN lesion"],
    ["Common Causes", "Stroke, spinal cord injury, cerebral palsy, MS"],
    ["Treatment", "Baclofen, tizanidine, botulinum toxin, physio"],
  ];

  spastCol1.forEach((item, i) => {
    s.addShape("rect", { x: 0.3, y: 2.3 + i * 0.72, w: 2.0, h: 0.6, fill: { color: "E74C3C" } });
    s.addText(item[0], { x: 0.3, y: 2.32 + i * 0.72, w: 2.0, h: 0.56, fontSize: 11, bold: true, color: LIGHT_TXT, align: "center", fontFace: "Calibri" });
    s.addShape("rect", { x: 2.35, y: 2.3 + i * 0.72, w: 2.35, h: 0.6, fill: { color: CARD_BG } });
    s.addText(item[1], { x: 2.4, y: 2.32 + i * 0.72, w: 2.25, h: 0.56, fontSize: 11, color: SOFT_TXT, fontFace: "Calibri" });
  });

  spastCol2.forEach((item, i) => {
    s.addShape("rect", { x: 5.0, y: 2.3 + i * 0.72, w: 2.0, h: 0.6, fill: { color: "C0392B" } });
    s.addText(item[0], { x: 5.0, y: 2.32 + i * 0.72, w: 2.0, h: 0.56, fontSize: 11, bold: true, color: LIGHT_TXT, align: "center", fontFace: "Calibri" });
    s.addShape("rect", { x: 7.05, y: 2.3 + i * 0.72, w: 2.6, h: 0.6, fill: { color: CARD_BG } });
    s.addText(item[1], { x: 7.1, y: 2.32 + i * 0.72, w: 2.5, h: 0.56, fontSize: 11, color: SOFT_TXT, fontFace: "Calibri" });
  });
}

// ─── SLIDE 10: Rigidity ───────────────────────────────────────────────────────
{
  const s = darkSlide(pres);
  addTopBar(s, ACCENT2);
  addBottomBar(s, ACCENT2);

  s.addText("08 — HYPERTONIA (II)", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: ACCENT2, bold: true, charSpacing: 4
  });
  s.addText("Rigidity", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 34, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  s.addShape("rect", { x: 0.3, y: 1.4, w: 9.4, h: 0.7, fill: { color: ACCENT2 } });
  s.addText('Velocity-INDEPENDENT increased resistance to passive movement — due to EXTRAPYRAMIDAL (basal ganglia) lesion', {
    x: 0.5, y: 1.45, w: 9.0, h: 0.6,
    fontSize: 14, color: DARK_TXT, bold: true, align: "center", fontFace: "Calibri"
  });

  const rigData = [
    ["Type: Lead Pipe", "Continuous uniform resistance throughout full ROM — like bending a lead pipe"],
    ["Type: Cogwheel", "Ratchet-like intermittent resistance — tremor superimposed on rigidity"],
    ["Velocity Dependence", "DOES NOT increase with velocity (distinguishes from spasticity)"],
    ["Distribution", "Affects both flexor AND extensor groups; tends toward flexed posture"],
    ["Reflexes", "Tendon reflexes are NOT enhanced (unlike spasticity)"],
    ["Pathology", "Extrapyramidal — basal ganglia: Parkinson disease, Wilson disease, drug-induced"],
    ["Paratonia", "Gegenhalten — patient resists all passive movements equally (frontal lobe lesion)"],
  ];

  rigData.forEach((d, i) => {
    s.addShape("rect", { x: 0.3, y: 2.25 + i * 0.46, w: 2.2, h: 0.38, fill: { color: ACCENT2 } });
    s.addText(d[0], { x: 0.35, y: 2.27 + i * 0.46, w: 2.1, h: 0.34, fontSize: 11, bold: true, color: DARK_TXT, align: "center", fontFace: "Calibri" });
    s.addText(d[1], { x: 2.65, y: 2.27 + i * 0.46, w: 7.0, h: 0.34, fontSize: 12, color: SOFT_TXT, fontFace: "Calibri" });
  });
}

// ─── SLIDE 11: Hypotonia ──────────────────────────────────────────────────────
{
  const s = midSlide(pres);
  addTopBar(s, "3498DB");
  addBottomBar(s, "3498DB");

  s.addText("09 — HYPOTONIA", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: "3498DB", bold: true, charSpacing: 4
  });
  s.addText("Hypotonia — Causes & Features", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 28, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  s.addShape("rect", { x: 0.3, y: 1.4, w: 9.4, h: 0.6, fill: { color: "2471A3" } });
  s.addText("Decreased resistance to passive movement — muscle feels soft, floppy, and overly compliant", {
    x: 0.45, y: 1.45, w: 9.0, h: 0.5,
    fontSize: 14, color: LIGHT_TXT, italic: true, align: "center", fontFace: "Calibri"
  });

  // Features column
  s.addText("Clinical Features", {
    x: 0.3, y: 2.1, w: 4.5, h: 0.4,
    fontSize: 14, bold: true, color: "3498DB", fontFace: "Calibri"
  });
  const features = [
    "Limb feels floppy and offers no resistance to passive movement",
    "Joints passively hyperextensible",
    "Muscle bulk may be reduced (atrophy in chronic LMN)",
    "Reduced or absent deep tendon reflexes (hyporeflexia / areflexia)",
    "Infant: 'floppy baby' — slip-through sign on axillary suspension",
    "Posture: limbs hang loosely in gravity-dependent positions",
  ];
  features.forEach((f, i) => {
    s.addShape("ellipse", { x: 0.3, y: 2.62 + i * 0.46, w: 0.2, h: 0.2, fill: { color: "3498DB" } });
    s.addText(f, { x: 0.6, y: 2.6 + i * 0.46, w: 4.3, h: 0.4, fontSize: 12, color: SOFT_TXT, fontFace: "Calibri" });
  });

  // Causes column
  s.addText("Common Causes", {
    x: 5.2, y: 2.1, w: 4.5, h: 0.4,
    fontSize: 14, bold: true, color: ACCENT2, fontFace: "Calibri"
  });
  const causes = [
    ["LMN Lesion", "Peripheral nerve, anterior horn cell"],
    ["Cerebellar", "Cerebellar lesion → hypotonia + ataxia"],
    ["Acute UMN", "Spinal shock phase after cord injury"],
    ["Muscle Disease", "Muscular dystrophy, myopathy"],
    ["Neuromuscular Jn", "Myasthenia gravis, botulism"],
    ["Metabolic", "Hypothyroidism, electrolyte disturbance"],
  ];
  causes.forEach((c, i) => {
    s.addShape("rect", { x: 5.2, y: 2.6 + i * 0.46, w: 1.7, h: 0.36, fill: { color: ACCENT2 } });
    s.addText(c[0], { x: 5.2, y: 2.62 + i * 0.46, w: 1.7, h: 0.32, fontSize: 10.5, bold: true, color: DARK_TXT, align: "center", fontFace: "Calibri" });
    s.addText(c[1], { x: 7.0, y: 2.62 + i * 0.46, w: 2.7, h: 0.32, fontSize: 11, color: SOFT_TXT, fontFace: "Calibri" });
  });
}

// ─── SLIDE 12: Clinical Assessment ───────────────────────────────────────────
{
  const s = darkSlide(pres);
  addTopBar(s, ACCENT);
  addBottomBar(s, ACCENT);

  s.addText("10 — ASSESSMENT", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: ACCENT, bold: true, charSpacing: 4
  });
  s.addText("Clinical Assessment of Muscle Tone", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 26, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  const steps = [
    {
      num: "1", title: "Inspection",
      text: "Observe resting posture. Spastic upper limb: flexed arm, extended leg. Hypotonic: limbs hang loosely."
    },
    {
      num: "2", title: "Palpation",
      text: "Feel the muscle at rest. Hypertonic muscles feel firm; hypotonic muscles feel soft and doughy."
    },
    {
      num: "3", title: "Passive Resistance",
      text: "Move the joint through full ROM. Ask patient: 'Don't help or resist — just let go.' Note velocity dependence."
    },
    {
      num: "4", title: "Velocity Test",
      text: "Perform slow then rapid passive movement. Spasticity increases with speed; rigidity does not change."
    },
    {
      num: "5", title: "Leg Drop Test",
      text: "Supine: lift knee and briskly flex hip. In spasticity, heel lifts off table. Normally heel stays down."
    },
    {
      num: "6", title: "Pendulum Test",
      text: "Seated, let leg swing freely. Hypotonic: swings many times. Hypertonic: stops quickly after 1-2 swings."
    },
    {
      num: "7", title: "Reflexes",
      text: "Tendon reflexes supplement tone assessment: hyperreflexia (UMN), hyporeflexia/areflexia (LMN/cerebellar)."
    },
  ];

  steps.forEach((st, i) => {
    const row = Math.floor(i / 4);
    const col = i % 4;
    if (i < 4) {
      s.addShape("ellipse", { x: 0.25 + col * 2.4, y: 1.45, w: 0.42, h: 0.42, fill: { color: ACCENT } });
      s.addText(st.num, { x: 0.25 + col * 2.4, y: 1.45, w: 0.42, h: 0.42, fontSize: 14, bold: true, color: DARK_TXT, align: "center", valign: "middle" });
      s.addShape("rect", { x: 0.25 + col * 2.4, y: 1.9, w: 2.1, h: 1.5, fill: { color: CARD_BG }, line: { color: ACCENT, width: 1 } });
      s.addText(st.title, { x: 0.3 + col * 2.4, y: 1.95, w: 2.0, h: 0.35, fontSize: 12, bold: true, color: ACCENT, fontFace: "Calibri" });
      s.addText(st.text, { x: 0.3 + col * 2.4, y: 2.35, w: 2.0, h: 1.0, fontSize: 10.5, color: SOFT_TXT, fontFace: "Calibri" });
    } else {
      const ci = i - 4;
      s.addShape("ellipse", { x: 0.25 + ci * 3.18, y: 3.55, w: 0.42, h: 0.42, fill: { color: ACCENT2 } });
      s.addText(st.num, { x: 0.25 + ci * 3.18, y: 3.55, w: 0.42, h: 0.42, fontSize: 14, bold: true, color: DARK_TXT, align: "center", valign: "middle" });
      s.addShape("rect", { x: 0.25 + ci * 3.18, y: 4.0, w: 2.8, h: 1.22, fill: { color: CARD_BG }, line: { color: ACCENT2, width: 1 } });
      s.addText(st.title, { x: 0.3 + ci * 3.18, y: 4.05, w: 2.65, h: 0.35, fontSize: 12, bold: true, color: ACCENT2, fontFace: "Calibri" });
      s.addText(st.text, { x: 0.3 + ci * 3.18, y: 4.45, w: 2.65, h: 0.7, fontSize: 10.5, color: SOFT_TXT, fontFace: "Calibri" });
    }
  });
}

// ─── SLIDE 13: UMN vs LMN ─────────────────────────────────────────────────────
{
  const s = lightSlide(pres);
  addTopBar(s, MID_BG);
  addBottomBar(s, MID_BG);

  s.addText("11 — UMN vs LMN", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: MID_BG, bold: true, charSpacing: 4
  });
  s.addText("Upper vs Lower Motor Neuron Lesions & Tone", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 24, bold: true, color: DARK_TXT, fontFace: "Calibri"
  });

  const headers = ["Feature", "UMN Lesion", "LMN Lesion"];
  const rows = [
    ["Tone", "Hypertonia (spasticity)", "Hypotonia (flaccidity)"],
    ["Reflexes", "Hyperreflexia, clonus", "Hyporeflexia / areflexia"],
    ["Babinski Sign", "Positive (extensor plantar)", "Absent / flexor response"],
    ["Muscle Bulk", "Mild disuse atrophy (late)", "Marked atrophy (early)"],
    ["Fasciculations", "Absent", "Present (denervation)"],
    ["Weakness Pattern", "Pyramidal distribution", "Flaccid, individual muscle"],
    ["Examples", "Stroke, cord injury, MS", "Polio, GBS, nerve palsy"],
  ];

  const colW = [2.4, 3.4, 3.4];
  const colX = [0.3, 2.8, 6.3];
  const rowH = 0.44;

  // Header row
  headers.forEach((h, ci) => {
    const bg = ci === 0 ? MID_BG : ci === 1 ? "D5522A" : "1A6DA8";
    s.addShape("rect", { x: colX[ci], y: 1.45, w: colW[ci], h: 0.42, fill: { color: bg } });
    s.addText(h, { x: colX[ci], y: 1.47, w: colW[ci], h: 0.38, fontSize: 13, bold: true, color: LIGHT_TXT, align: "center", fontFace: "Calibri" });
  });

  rows.forEach((row, ri) => {
    const y = 1.9 + ri * rowH;
    const bg = ri % 2 === 0 ? "EBF5FB" : "D6EAF8";
    row.forEach((cell, ci) => {
      const bgc = ci === 0 ? "D6EAF8" : bg;
      s.addShape("rect", { x: colX[ci], y, w: colW[ci], h: rowH - 0.04, fill: { color: bgc }, line: { color: "AED6F1", width: 0.5 } });
      s.addText(cell, {
        x: colX[ci] + 0.05, y: y + 0.04, w: colW[ci] - 0.1, h: rowH - 0.12,
        fontSize: 12, color: DARK_TXT, fontFace: "Calibri",
        bold: ci === 0
      });
    });
  });
}

// ─── SLIDE 14: Clasp-Knife & Lead-Pipe ───────────────────────────────────────
{
  const s = darkSlide(pres);
  addTopBar(s, "E74C3C");
  addBottomBar(s, "E74C3C");

  s.addText("12 — CLINICAL SIGNS", {
    x: 0.5, y: 0.2, w: 9, h: 0.4,
    fontSize: 10, color: "E74C3C", bold: true, charSpacing: 4
  });
  s.addText("Clasp-Knife vs Lead-Pipe Phenomenon", {
    x: 0.5, y: 0.6, w: 9, h: 0.65,
    fontSize: 24, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  // Clasp-knife box
  s.addShape("rect", { x: 0.3, y: 1.45, w: 4.5, h: 3.8, fill: { color: CARD_BG }, line: { color: "E74C3C", width: 2 } });
  s.addShape("rect", { x: 0.3, y: 1.45, w: 4.5, h: 0.45, fill: { color: "E74C3C" } });
  s.addText("🔪 CLASP-KNIFE (Spasticity)", {
    x: 0.35, y: 1.47, w: 4.4, h: 0.41,
    fontSize: 13, bold: true, color: LIGHT_TXT, align: "center", fontFace: "Calibri"
  });
  const ckPts = [
    "Named after closing a pocket knife",
    "Initial high resistance to passive stretch",
    "Then sudden COLLAPSE of resistance",
    "Due to activation of Golgi Tendon Organ (GTO)",
    "GTO-mediated inhibition silences the agonist",
    "Velocity dependent — faster = greater initial resistance",
    "Classic UMN / corticospinal tract sign",
    "Seen at elbow (biceps) and knee (quadriceps)",
  ];
  ckPts.forEach((p, i) => {
    s.addText("• " + p, { x: 0.4, y: 2.02 + i * 0.38, w: 4.3, h: 0.34, fontSize: 11.5, color: SOFT_TXT, fontFace: "Calibri" });
  });

  // Lead-pipe box
  s.addShape("rect", { x: 5.2, y: 1.45, w: 4.5, h: 3.8, fill: { color: CARD_BG }, line: { color: ACCENT2, width: 2 } });
  s.addShape("rect", { x: 5.2, y: 1.45, w: 4.5, h: 0.45, fill: { color: ACCENT2 } });
  s.addText("🔩 LEAD-PIPE (Rigidity)", {
    x: 5.25, y: 1.47, w: 4.4, h: 0.41,
    fontSize: 13, bold: true, color: DARK_TXT, align: "center", fontFace: "Calibri"
  });
  const lpPts = [
    "Named after bending a lead pipe",
    "UNIFORM resistance throughout entire ROM",
    "No collapse — resistance remains constant",
    "Not velocity dependent",
    "Affects both flexors and extensors equally",
    "Extrapyramidal / basal ganglia pathology",
    "Parkinson disease: lead-pipe + cogwheeling",
    "Cogwheeling = lead-pipe + superimposed tremor",
  ];
  lpPts.forEach((p, i) => {
    s.addText("• " + p, { x: 5.3, y: 2.02 + i * 0.38, w: 4.3, h: 0.34, fontSize: 11.5, color: SOFT_TXT, fontFace: "Calibri" });
  });
}

// ─── SLIDE 15: Summary / Outro ────────────────────────────────────────────────
{
  const s = darkSlide(pres);
  s.addShape("rect", { x: 0, y: 0, w: 10, h: 0.2, fill: { color: ACCENT } });
  s.addShape("rect", { x: 0, y: 5.425, w: 10, h: 0.2, fill: { color: ACCENT } });

  s.addText("15 — SUMMARY", {
    x: 0.5, y: 0.3, w: 9, h: 0.4,
    fontSize: 10, color: ACCENT, bold: true, charSpacing: 5
  });
  s.addText("Key Clinical Pearls", {
    x: 0.5, y: 0.72, w: 9, h: 0.6,
    fontSize: 30, bold: true, color: LIGHT_TXT, fontFace: "Calibri"
  });

  const pearls = [
    ["Tone ≠ Strength", "Tone is the resting background state; strength is voluntary force generation"],
    ["Velocity matters", "If resistance increases with speed → spasticity (UMN); if not → rigidity (extrapyramidal)"],
    ["Clasp-knife = UMN", "Sudden release of resistance = GTO activation — marks corticospinal lesion"],
    ["Cogwheeling = PD", "Ratchet-like resistance = lead-pipe rigidity + tremor — hallmark of Parkinson disease"],
    ["Hypotonia + areflexia", "Think LMN lesion (anterior horn, peripheral nerve) or cerebellar disease"],
    ["Spinal shock", "Acute complete cord injury → initial hypotonia/areflexia → later spasticity"],
    ["Gamma loop key", "High γ discharge → hypertonia; low γ → hypotonia — cerebellum modulates γ"],
  ];

  pearls.forEach((p, i) => {
    const col = i < 4 ? 0 : 1;
    const row = col === 0 ? i : i - 4;
    const x = col === 0 ? 0.3 : 5.1;
    const y = 1.52 + row * 0.88;
    const bg = col === 0 ? ACCENT : ACCENT2;

    s.addShape("rect", { x, y, w: 4.6, h: 0.8, fill: { color: CARD_BG }, line: { color: bg, width: 1.5 } });
    s.addShape("rect", { x, y, w: 1.75, h: 0.8, fill: { color: bg } });
    s.addText(p[0], { x, y: y + 0.1, w: 1.75, h: 0.6, fontSize: 11, bold: true, color: DARK_TXT, align: "center", fontFace: "Calibri" });
    s.addText(p[1], { x: x + 1.85, y: y + 0.1, w: 2.65, h: 0.6, fontSize: 11, color: SOFT_TXT, fontFace: "Calibri" });
  });
}

// ─── Write File ───────────────────────────────────────────────────────────────
pres.writeFile({ fileName: "/home/daytona/workspace/muscle-tone-ppt/Muscle_Tone.pptx" })
  .then(() => console.log("✅ Created: /home/daytona/workspace/muscle-tone-ppt/Muscle_Tone.pptx"))
  .catch(e => { console.error("❌ Error:", e.message); process.exit(1); });