import type PptxGenJSModule from 'pptxgenjs'

let _PptxGenJS: (new () => PptxGenJSModule) | null = null
async function getPptxGenClass(): Promise<new () => PptxGenJSModule> {
  if (!_PptxGenJS) {
    const mod = await import('pptxgenjs')
    _PptxGenJS = (mod.default ?? mod) as unknown as new () => PptxGenJSModule
  }
  return _PptxGenJS
}

// ── Theme — cohérent avec l'identité visuelle Memento ───────────────────────
const T = {
  bg:        'F2F0E9',
  primary:   '1C1C1C',
  accent:    'A47148',
  secondary: 'D4A373',
  muted:     '9A8C87',
  wave1:     'fb923c',
  wave2:     '60a5fa',
  wave3:     'a78bfa',
  green:     '10b981',
}

const WAVE_LABELS: Record<number, string> = {
  1: '🔄 Variations',
  2: '🔗 Analogies',
  3: '💥 Disruptions',
}

const WAVE_COLORS: Record<number, string> = {
  1: T.wave1,
  2: T.wave2,
  3: T.wave3,
}

// ── Types (minimal subset) ──────────────────────────────────────────────────

interface IdeaLike {
  id: string
  title: string
  description: string
  waveNumber: number
  status: string
  isStarred: boolean
  convertedToNoteId: string | null
}

interface SessionLike {
  seedIdea: string
  createdAt: Date
  ideas: IdeaLike[]
}

// ── Helpers ─────────────────────────────────────────────────────────────────

function slugify(text: string): string {
  return text
    .toLowerCase()
    .replace(/[^a-z0-9\s-]/g, '')
    .replace(/\s+/g, '-')
    .slice(0, 40)
}

function truncate(text: string, max: number): string {
  return text.length > max ? text.slice(0, max - 1) + '…' : text
}

/**
 * PLG viral watermark — added to every slide automatically via addSlide monkey-patch.
 * LAYOUT_WIDE = 13.33" × 7.5" → watermark anchored near bottom-right at y ≈ 7.1
 */
function addWatermark(slide: any) {
  slide.addText('memento-note.com', {
    x: 10.0, y: 7.1, w: 3.0, h: 0.25,
    fontSize: 7, fontFace: 'Arial', color: 'B8B0A8',
    align: 'right', italic: true,
  })
}

/** Wrap pres.addSlide so every new slide gets the Memento watermark automatically */
function withWatermark(pres: PptxGenJSModule): PptxGenJSModule {
  const original = pres.addSlide.bind(pres)
  ;(pres as any).addSlide = (...args: any[]) => {
    const slide = original(...args)
    addWatermark(slide)
    return slide
  }
  return pres
}

// Add a consistent slide background
function addBg(slide: any) {
  slide.background = { color: T.bg }
}

// Accent bar at the top of a slide
function addTopBar(slide: any, color: string = T.accent) {
  slide.addShape('rect', { x: 0, y: 0, w: '100%', h: 0.12, fill: { color } })
}

// ── Slide builders ───────────────────────────────────────────────────────────

function buildCoverSlide(pres: PptxGenJSModule, session: SessionLike, stats: { total: number; converted: number; starred: number }) {
  const slide = pres.addSlide()
  addBg(slide)

  // Left accent panel
  slide.addShape('rect', { x: 0, y: 0, w: 3.6, h: '100%', fill: { color: T.primary } })

  // Brand label on accent panel
  slide.addText('MOMENTO', {
    x: 0.3, y: 0.4, w: 3.0, h: 0.4,
    fontSize: 9, fontFace: 'Arial', color: T.accent, bold: true,
    charSpacing: 4, align: 'left',
  })

  // Seed idea (big) on right
  slide.addText(truncate(session.seedIdea, 80), {
    x: 4.0, y: 1.2, w: 5.6, h: 2.4,
    fontSize: 26, fontFace: 'Georgia', color: T.primary,
    bold: false, align: 'left', valign: 'middle', wrap: true,
  })

  // Date
  slide.addText(session.createdAt.toLocaleDateString('fr-FR', { day: 'numeric', month: 'long', year: 'numeric' }), {
    x: 4.0, y: 4.0, w: 5.6, h: 0.4,
    fontSize: 10, fontFace: 'Arial', color: T.muted, align: 'left',
  })

  // Stats row
  const statItems = [
    { label: 'idées', value: String(stats.total) },
    { label: 'converties', value: String(stats.converted) },
    { label: 'favorites', value: String(stats.starred) },
  ]
  statItems.forEach((s, i) => {
    const x = 4.0 + i * 2.0
    slide.addText(s.value, { x, y: 4.8, w: 1.8, h: 0.55, fontSize: 22, fontFace: 'Georgia', color: T.accent, bold: true, align: 'left' })
    slide.addText(s.label, { x, y: 5.35, w: 1.8, h: 0.3, fontSize: 9, fontFace: 'Arial', color: T.muted, align: 'left', charSpacing: 1 })
  })

  // Vertical label "BRAINSTORM" on left panel
  slide.addText('BRAINSTORM', {
    x: 0.1, y: 2.0, w: 3.2, h: 0.5,
    fontSize: 11, fontFace: 'Arial', color: 'FFFFFF', bold: true,
    charSpacing: 6, align: 'center',
    rotate: 270,
  })
}

function buildWaveSlide(pres: PptxGenJSModule, wave: number, ideas: IdeaLike[]) {
  const slide = pres.addSlide()
  addBg(slide)
  addTopBar(slide, WAVE_COLORS[wave] || T.accent)

  // Wave label
  slide.addText(WAVE_LABELS[wave] || `Wave ${wave}`, {
    x: 0.5, y: 0.25, w: 9.0, h: 0.5,
    fontSize: 14, fontFace: 'Arial', color: WAVE_COLORS[wave] || T.accent, bold: true, charSpacing: 2,
  })

  // Count badge
  slide.addShape('roundRect', { x: 9.0, y: 0.28, w: 0.6, h: 0.4, fill: { color: WAVE_COLORS[wave] || T.accent }, rectRadius: 0.1 })
  slide.addText(String(ideas.length), { x: 9.0, y: 0.28, w: 0.6, h: 0.4, fontSize: 11, fontFace: 'Arial', color: 'FFFFFF', bold: true, align: 'center', valign: 'middle' })

  const maxPerSlide = 6
  const shown = ideas.slice(0, maxPerSlide)

  const colW = 4.5
  const rowH = 1.3
  const startY = 1.0

  shown.forEach((idea, i) => {
    const col = i % 2
    const row = Math.floor(i / 2)
    const x = 0.4 + col * (colW + 0.3)
    const y = startY + row * (rowH + 0.15)

    // Card background
    slide.addShape('roundRect', { x, y, w: colW, h: rowH, fill: { color: 'FFFFFF' }, line: { color: 'E8E6E0', width: 0.75 }, rectRadius: 0.08 })

    // Star / converted badge
    if (idea.isStarred || idea.convertedToNoteId) {
      const badge = idea.convertedToNoteId ? '✓' : '⭐'
      const badgeColor = idea.convertedToNoteId ? T.green : T.wave1
      slide.addText(badge, { x: x + colW - 0.45, y: y + 0.08, w: 0.35, h: 0.35, fontSize: 10, fontFace: 'Arial', color: badgeColor, align: 'center' })
    }

    // Title
    slide.addText(truncate(idea.title, 55), {
      x: x + 0.18, y: y + 0.12, w: colW - 0.55, h: 0.4,
      fontSize: 11, fontFace: 'Arial', color: T.primary, bold: true, wrap: true,
    })

    // Description
    slide.addText(truncate(idea.description, 120), {
      x: x + 0.18, y: y + 0.52, w: colW - 0.36, h: 0.65,
      fontSize: 9, fontFace: 'Arial', color: T.muted, wrap: true, valign: 'top',
    })
  })

  if (ideas.length > maxPerSlide) {
    slide.addText(`+ ${ideas.length - maxPerSlide} autres idées`, {
      x: 0.4, y: 5.5, w: 9.2, h: 0.3,
      fontSize: 9, fontFace: 'Arial', color: T.muted, align: 'center', italic: true,
    })
  }
}

function buildTopIdeasSlide(pres: PptxGenJSModule, starred: IdeaLike[], converted: IdeaLike[]) {
  const slide = pres.addSlide()
  addBg(slide)
  addTopBar(slide, T.accent)

  slide.addText('Top Idées', {
    x: 0.5, y: 0.25, w: 9.0, h: 0.5,
    fontSize: 14, fontFace: 'Arial', color: T.accent, bold: true, charSpacing: 2,
  })

  const all = [
    ...starred.map(i => ({ ...i, badge: '⭐', badgeColor: T.wave1 })),
    ...converted.filter(i => !i.isStarred).map(i => ({ ...i, badge: '✓', badgeColor: T.green })),
  ].slice(0, 6)

  if (all.length === 0) {
    slide.addText('Aucune idée favorite ou convertie.', {
      x: 0.5, y: 3.0, w: 9.0, h: 0.5,
      fontSize: 12, fontFace: 'Georgia', color: T.muted, align: 'center', italic: true,
    })
    return
  }

  const colW = 4.5
  const rowH = 1.25

  all.forEach((idea, i) => {
    const col = i % 2
    const row = Math.floor(i / 2)
    const x = 0.4 + col * (colW + 0.3)
    const y = 1.1 + row * (rowH + 0.15)

    const waveColor = WAVE_COLORS[idea.waveNumber] || T.muted

    slide.addShape('roundRect', { x, y, w: colW, h: rowH, fill: { color: 'FFFFFF' }, line: { color: waveColor, width: 1.5 }, rectRadius: 0.08 })

    slide.addText(idea.badge, { x: x + 0.1, y: y + 0.1, w: 0.4, h: 0.4, fontSize: 14, fontFace: 'Arial', color: idea.badgeColor, align: 'center' })

    slide.addText(truncate(idea.title, 55), {
      x: x + 0.55, y: y + 0.1, w: colW - 0.7, h: 0.4,
      fontSize: 11, fontFace: 'Arial', color: T.primary, bold: true, wrap: true,
    })

    slide.addText(truncate(idea.description, 110), {
      x: x + 0.18, y: y + 0.55, w: colW - 0.36, h: 0.6,
      fontSize: 9, fontFace: 'Arial', color: T.muted, wrap: true, valign: 'top',
    })
  })
}

function buildSummarySlide(pres: PptxGenJSModule, session: SessionLike, stats: { total: number; converted: number; starred: number; dismissed: number }) {
  const slide = pres.addSlide()
  addBg(slide)
  addTopBar(slide, T.accent)

  slide.addText('BILAN DE SESSION', {
    x: 0.8, y: 0.25, w: 11.5, h: 0.5,
    fontSize: 10, fontFace: 'Arial', color: T.accent, bold: true, charSpacing: 5, align: 'left',
  })

  slide.addText(truncate(session.seedIdea, 80), {
    x: 0.8, y: 0.9, w: 11.5, h: 1.0,
    fontSize: 20, fontFace: 'Georgia', color: T.primary, align: 'left', wrap: true,
  })

  // Divider
  slide.addShape('rect', { x: 0.8, y: 2.1, w: 11.5, h: 0.02, fill: { color: T.accent } })

  // Stats cards
  const statCols = [
    { label: 'IDÉES GÉNÉRÉES', value: String(stats.total), color: T.wave2, bg: 'EEF6FF' },
    { label: 'CONVERTIES EN NOTES', value: String(stats.converted), color: T.green, bg: 'EDFAF4' },
    { label: 'FAVORITES', value: String(stats.starred), color: T.wave1, bg: 'FFF4EE' },
    { label: 'REJETÉES', value: String(stats.dismissed), color: T.muted, bg: 'F5F4F2' },
  ]

  const cardW = 2.7
  const cardH = 2.8
  const startX = 0.8
  const startY = 2.3

  statCols.forEach((s, i) => {
    const x = startX + i * (cardW + 0.2)
    // Card bg
    slide.addShape('roundRect', { x, y: startY, w: cardW, h: cardH, fill: { color: s.bg }, rectRadius: 0.1 })
    // Top accent strip
    slide.addShape('roundRect', { x, y: startY, w: cardW, h: 0.1, fill: { color: s.color }, rectRadius: 0.05 })
    // Big number
    slide.addText(s.value, { x: x + 0.2, y: startY + 0.35, w: cardW - 0.4, h: 1.2, fontSize: 48, fontFace: 'Georgia', color: s.color, bold: true, align: 'left', valign: 'middle' })
    // Label
    slide.addText(s.label, { x: x + 0.2, y: startY + 1.7, w: cardW - 0.4, h: 0.9, fontSize: 8, fontFace: 'Arial', color: T.muted, align: 'left', charSpacing: 1.5, wrap: true })
  })
}

// ── Main export function ─────────────────────────────────────────────────────

export async function generateBrainstormPptx(session: SessionLike): Promise<{ buffer: Buffer; filename: string }> {
  const PptxGenJS = await getPptxGenClass()
  const pres = withWatermark(new PptxGenJS())

  pres.layout = 'LAYOUT_WIDE'
  pres.author = 'Memento'
  pres.subject = `Brainstorm: ${session.seedIdea}`

  const activeIdeas = session.ideas.filter(i => i.status !== 'dismissed')
  const dismissedCount = session.ideas.filter(i => i.status === 'dismissed').length
  const converted = activeIdeas.filter(i => i.convertedToNoteId !== null)
  const starred = activeIdeas.filter(i => i.isStarred)

  const stats = {
    total: activeIdeas.length,
    converted: converted.length,
    starred: starred.length,
    dismissed: dismissedCount,
  }

  // Slide 1 — Cover
  buildCoverSlide(pres, session, stats)

  // Slides 2-4 — One per active wave
  for (const wave of [1, 2, 3]) {
    const waveIdeas = activeIdeas.filter(i => i.waveNumber === wave)
    if (waveIdeas.length === 0) continue
    buildWaveSlide(pres, wave, waveIdeas)
  }

  // Slide N — Top ideas (starred + converted)
  if (starred.length > 0 || converted.length > 0) {
    buildTopIdeasSlide(pres, starred, converted)
  }

  // Last slide — Summary
  buildSummarySlide(pres, session, stats)

  const buffer = (await pres.write({ outputType: 'nodebuffer' })) as unknown as Buffer
  const filename = `brainstorm-${slugify(session.seedIdea)}.pptx`

  return { buffer, filename }
}