import { Router } from 'express'
import db from '../db.js'
import { auth } from '../middleware/auth.js'
import { generateEpub } from '../lib/epub.js'
import { generateOdt } from '../lib/odt.js'

const router = Router()
router.use(auth)

const parse = s => { try { return JSON.parse(s || '{}') } catch { return {} } }
const safe = s => JSON.stringify(s ?? {})

router.get('/', (req, res) => {
  const rows = db.prepare(
    'SELECT id, title, content, cover_image, updated_at, created_at FROM stories WHERE user_id = ? ORDER BY updated_at DESC'
  ).all(req.user.id)
  res.json(rows.map(r => ({ ...r, content: parse(r.content) })))
})

router.get('/:id', (req, res) => {
  const story = db.prepare(
    'SELECT id, title, content, cover_image, updated_at, created_at FROM stories WHERE id = ? AND user_id = ?'
  ).get(req.params.id, req.user.id)
  if (!story) return res.status(404).json({ error: 'Not found' })
  res.json({ ...story, content: parse(story.content) })
})

router.post('/', (req, res) => {
  const { title = 'Untitled Story', content = {} } = req.body || {}
  const { lastInsertRowid } = db.prepare(
    'INSERT INTO stories (user_id, title, content) VALUES (?, ?, ?)'
  ).run(req.user.id, title, safe(content))
  const story = db.prepare('SELECT * FROM stories WHERE id = ?').get(lastInsertRowid)
  res.json({ ...story, content: parse(story.content) })
})

router.put('/:id', (req, res) => {
  const story = db.prepare('SELECT * FROM stories WHERE id = ? AND user_id = ?').get(req.params.id, req.user.id)
  if (!story) return res.status(404).json({ error: 'Not found' })

  const { title, content, cover_image } = req.body || {}
  db.prepare(
    'UPDATE stories SET title = ?, content = ?, cover_image = ?, updated_at = CURRENT_TIMESTAMP WHERE id = ?'
  ).run(
    title      ?? story.title,
    content    !== undefined ? safe(content)    : story.content,
    cover_image !== undefined ? cover_image      : story.cover_image,
    req.params.id
  )
  const updated = db.prepare('SELECT * FROM stories WHERE id = ?').get(req.params.id)
  res.json({ ...updated, content: parse(updated.content) })
})

router.delete('/:id', (req, res) => {
  const story = db.prepare('SELECT * FROM stories WHERE id = ? AND user_id = ?').get(req.params.id, req.user.id)
  if (!story) return res.status(404).json({ error: 'Not found' })
  db.prepare('DELETE FROM stories WHERE id = ?').run(req.params.id)
  res.json({ ok: true })
})

// ── Exports ──────────────────────────────────────────────

router.get('/:id/export/epub', async (req, res) => {
  const story = db.prepare('SELECT * FROM stories WHERE id = ? AND user_id = ?').get(req.params.id, req.user.id)
  if (!story) return res.status(404).json({ error: 'Not found' })
  try {
    const buf = await generateEpub({ ...story, content: parse(story.content) })
    const fname = (story.title || 'story').replace(/[^\w\s-]/g, '').trim().replace(/\s+/g, '_') + '.epub'
    res.set({ 'Content-Type': 'application/epub+zip', 'Content-Disposition': `attachment; filename="${fname}"` })
    res.send(buf)
  } catch (err) {
    console.error('EPUB error:', err)
    res.status(500).json({ error: 'Export failed' })
  }
})

router.get('/:id/export/odt', async (req, res) => {
  const story = db.prepare('SELECT * FROM stories WHERE id = ? AND user_id = ?').get(req.params.id, req.user.id)
  if (!story) return res.status(404).json({ error: 'Not found' })
  try {
    const buf = await generateOdt({ ...story, content: parse(story.content) })
    const fname = (story.title || 'story').replace(/[^\w\s-]/g, '').trim().replace(/\s+/g, '_') + '.odt'
    res.set({ 'Content-Type': 'application/vnd.oasis.opendocument.text', 'Content-Disposition': `attachment; filename="${fname}"` })
    res.send(buf)
  } catch (err) {
    console.error('ODT error:', err)
    res.status(500).json({ error: 'Export failed' })
  }
})

export default router