import type {
  PageSection,
  PageSpecV1,
  PageValidationIssue,
} from '@/lib/interactive-page'

export type PagePlanDemoKind = 'svg-scene' | 'chart' | 'heatmap-matrix' | 'simulation' | 'none'

export type PagePlanSection = {
  title: string
  goal: string
  demoKind: PagePlanDemoKind
  demoGoal?: string
}

export type PagePlan = {
  heroTitle: string
  heroSubtitle?: string
  overviewLead: string
  overviewCards: {
    badge: string
    title: string
    body: string
    intent?: string
  }[]
  sections: PagePlanSection[]
}

export type GenerateInteractivePageResponse =
  | { ok: true; page: PageSpecV1; attempts: number }
  | {
      ok: false
      error: string
      reason?: string
      issues?: PageValidationIssue[]
      quotaExceeded?: boolean
      status?: number
    }

export type GeneratePlanResponse =
  | { ok: true; plan: PagePlan; attempts: number }
  | {
      ok: false
      error: string
      reason?: string
      quotaExceeded?: boolean
      status?: number
    }

export type GenerateSectionResponse =
  | { ok: true; section: PageSection; attempts: number }
  | { ok: false; error: string; status?: number }

async function postJson(
  body: Record<string, unknown>,
  timeoutMs = 55_000
): Promise<{ res: Response; data: Record<string, never> } | { abortError: true }> {
  const controller = new AbortController()
  const timeout = setTimeout(() => controller.abort(), timeoutMs)
  try {
    const res = await fetch('/api/ai/interactive-page', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify(body),
      signal: controller.signal,
    })
    const data = await res.json().catch(() => ({}))
    return { res, data }
  } catch (err) {
    if (err instanceof Error && err.name === 'AbortError') {
      return { abortError: true }
    }
    throw err
  } finally {
    clearTimeout(timeout)
  }
}

/** LLM plan (billed — 20 crédits). */
export async function generateInteractivePagePlan(params: {
  content: string
  lang?: string
  noteId?: string
}): Promise<GeneratePlanResponse> {
  let out: Awaited<ReturnType<typeof postJson>>
  try {
    out = await postJson({ ...params, action: 'plan' })
  } catch (err) {
    return {
      ok: false,
      error: err instanceof Error ? err.message : 'Network error',
    }
  }
  if ('abortError' in out) {
    return { ok: false, error: 'Génération trop longue — réessaie' }
  }
  const { res, data } = out as {
    res: Response
     
    data: any
  }
  if (res.status === 402) {
    return {
      ok: false,
      error: data.error || 'Quota exceeded',
      quotaExceeded: true,
      status: 402,
    }
  }
  if (!res.ok) {
    return {
      ok: false,
      error: data.error || `HTTP ${res.status}`,
      reason: data.reason,
      status: res.status,
    }
  }
  return { ok: true, plan: data.plan, attempts: data.attempts ?? 1 }
}

/** LLM single section (not billed — page billed at plan time). */
export async function generateInteractivePageSection(params: {
  content: string
  lang?: string
  noteId?: string
  pageTitle: string
  sectionId: string
  section: PagePlanSection
}): Promise<GenerateSectionResponse> {
  let out: Awaited<ReturnType<typeof postJson>>
  try {
    out = await postJson({ ...params, action: 'section' })
  } catch (err) {
    return {
      ok: false,
      error: err instanceof Error ? err.message : 'Network error',
    }
  }
  if ('abortError' in out) {
    return { ok: false, error: 'timeout' }
  }
  const { res, data } = out as {
    res: Response
     
    data: any
  }
  if (!res.ok) {
    return { ok: false, error: data.error || `HTTP ${res.status}`, status: res.status }
  }
  return { ok: true, section: data.section, attempts: data.attempts ?? 1 }
}

/** Legacy deterministic full page (fallback, no quota). */
export async function generateInteractivePage(params: {
  content: string
  lang?: string
  noteId?: string
  notebookId?: string
}): Promise<GenerateInteractivePageResponse> {
  const controller = new AbortController()
  const timeout = setTimeout(() => controller.abort(), 75_000)
  let res: Response
  try {
    res = await fetch('/api/ai/interactive-page', {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify(params),
      signal: controller.signal,
    })
  } catch (err) {
    clearTimeout(timeout)
    const aborted = err instanceof Error && err.name === 'AbortError'
    return {
      ok: false,
      error: aborted
        ? 'Génération trop longue — réessaie'
        : err instanceof Error
          ? err.message
          : 'Network error',
    }
  } finally {
    clearTimeout(timeout)
  }

  const data = await res.json().catch(() => ({}))

  if (res.status === 402) {
    return {
      ok: false,
      error: data.error || 'Quota exceeded',
      quotaExceeded: true,
      status: 402,
    }
  }

  if (!res.ok) {
    return {
      ok: false,
      error: data.error || `HTTP ${res.status}`,
      reason: data.reason,
      issues: data.issues,
      status: res.status,
    }
  }

  return {
    ok: true,
    page: data.page,
    attempts: data.attempts ?? 1,
  }
}