import { NextRequest, NextResponse } from 'next/server'
import prisma from '@/lib/prisma'
import { auth } from '@/auth'

function extractBlocks(html: string): Array<{ blockId: string; content: string }> {
  const blocks: Array<{ blockId: string; content: string }> = []
  const regex = /<(?:p|h[1-6]|blockquote)[^>]*data-id="([^"]+)"[^>]*>([\s\S]*?)<\/(?:p|h[1-6]|blockquote)>/gi
  let match
  while ((match = regex.exec(html)) !== null) {
    const blockId = match[1]
    const content = match[2].replace(/<[^>]+>/g, '').trim()
    if (content.length >= 20) {
      blocks.push({ blockId, content })
    }
  }
  return blocks
}

// GET /api/blocks/search?q=xxx&excludeNoteId=yyy
export async function GET(request: NextRequest) {
  const session = await auth()
  if (!session?.user?.id) {
    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
  }

  const q = request.nextUrl.searchParams.get('q')?.trim()
  const excludeNoteId = request.nextUrl.searchParams.get('excludeNoteId')

  if (!q) {
    return NextResponse.json({ blocks: [] })
  }

  const where: Record<string, unknown> = {
    userId: session.user.id,
    isArchived: false,
    trashedAt: null,
  }
  if (excludeNoteId) where.id = { not: excludeNoteId }

  const notes = await prisma.note.findMany({
    where,
    select: { id: true, title: true, content: true, notebookId: true },
    take: 80,
    orderBy: { updatedAt: 'desc' },
  })

  const notebookIds = [...new Set(notes.map(n => n.notebookId).filter(Boolean) as string[])]
  const notebooks = notebookIds.length > 0
    ? await prisma.notebook.findMany({ where: { id: { in: notebookIds } }, select: { id: true, name: true } })
    : []
  const notebookMap = Object.fromEntries(notebooks.map(nb => [nb.id, nb.name]))

  const qLower = q.toLowerCase()
  const results: Array<{
    blockId: string
    noteId: string
    noteTitle: string
    notebookName: string
    content: string
    snippet: string
  }> = []

  for (const note of notes) {
    const blocks = extractBlocks(note.content)
    for (const block of blocks) {
      if (!block.content.toLowerCase().includes(qLower) && !note.title?.toLowerCase().includes(qLower)) continue
      const words = block.content.split(/\s+/)
      const snippet = words.slice(0, 30).join(' ') + (words.length > 30 ? '…' : '')
      results.push({
        blockId: block.blockId,
        noteId: note.id,
        noteTitle: note.title || 'Sans titre',
        notebookName: note.notebookId ? (notebookMap[note.notebookId] || 'Général') : 'Général',
        content: block.content,
        snippet,
      })
      if (results.length >= 20) break
    }
    if (results.length >= 20) break
  }

  return NextResponse.json({ blocks: results })
}