import { Router } from 'express'
import { prisma } from '../db.js'
import { authRequired } from '../middleware.js'

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

// 系统预置模板 (builtin): 首次访问模板接口时幂等写入
const BUILTIN_TEMPLATES = [
  {
    name: '出差',
    scene: '出差',
    items: [
      { title: '身份证 / 证件' },
      { title: '手机充电器 + 充电宝' },
      { title: '笔记本电脑 + 电源' },
      { title: '耳机' },
      { title: '换洗衣物' },
      { title: '洗漱包' },
      { title: '常用药' },
      { title: '雨伞' },
      { title: '车票 / 机票 / 酒店确认' },
      { title: '工牌 / 名片' },
      { title: '报销单据' },
    ],
  },
  {
    name: '回老家',
    scene: '回老家',
    items: [
      { title: '身份证 / 证件' },
      { title: '钥匙' },
      { title: '手机充电器 + 充电宝' },
      { title: '换洗衣物' },
      { title: '洗漱包' },
      { title: '常用药' },
      { title: '给家人的礼物 / 伴手礼' },
      { title: '长辈的药品 / 营养品' },
      { title: '口罩' },
      { title: '现金零钱' },
      { title: '车票 / 加油 / 行程确认' },
      { title: '家里门窗水电检查' },
    ],
  },
]

export async function ensureBuiltin() {
  const count = await prisma.checkListTemplate.count({ where: { builtin: true } })
  if (count >= BUILTIN_TEMPLATES.length) return
  for (const t of BUILTIN_TEMPLATES) {
    const exist = await prisma.checkListTemplate.findFirst({ where: { builtin: true, name: t.name } })
    if (exist) continue
    await prisma.checkListTemplate.create({
      data: { name: t.name, scene: t.scene, items: t.items, builtin: true, userId: null },
    })
  }
}

const LIST_INCLUDE = { items: { orderBy: [{ sortOrder: 'asc' }, { id: 'asc' }] } }

function withProgress(list) {
  const items = list.items || []
  const done = items.filter((i) => i.done).length
  return {
    ...list,
    items,
    total: items.length,
    done,
    percent: items.length > 0 ? done / items.length : 0,
    completed: items.length > 0 && done === items.length,
  }
}

// ---------- 模板 ----------

// 模板按名称字母顺序 (中文按拼音) 排序, 前后端共用同一比较器语义
const NAME_COLLATOR = new Intl.Collator('zh-Hans-CN', { numeric: true, sensitivity: 'base' })
const byName = (a, b) => NAME_COLLATOR.compare(String(a.name || ''), String(b.name || ''))

// GET /api/checklists/templates   模板列表 (含系统预置, 按字母顺序)
router.get('/templates', async (_req, res, next) => {
  try {
    await ensureBuiltin()
    const rows = await prisma.checkListTemplate.findMany({
      where: { OR: [{ builtin: true }, { userId: _req.user.sub }] },
    })
    res.json({ items: rows.sort(byName) })
  } catch (e) { next(e) }
})

// GET /api/checklists/templates/:id   模板详情
router.get('/templates/:id', async (req, res, next) => {
  try {
    const row = await prisma.checkListTemplate.findFirst({
      where: { id: Number(req.params.id), OR: [{ builtin: true }, { userId: req.user.sub }] },
    })
    if (!row) return res.status(404).json({ error: '模板不存在' })
    res.json({ item: row })
  } catch (e) { next(e) }
})

// POST /api/checklists/templates  另存为模板 { name, scene?, items: [{title, note}] }
router.post('/templates', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const { name, scene = '', items = [] } = req.body || {}
    const cleanName = String(name || '').trim()
    if (!cleanName) return res.status(400).json({ error: '模板名称不能为空' })
    if (cleanName.length > 20) return res.status(400).json({ error: '模板名称不能超过 20 个字' })
    const list = (Array.isArray(items) ? items : [])
      .map((i) => ({ title: String(i?.title || '').trim(), note: String(i?.note || '') }))
      .filter((i) => i.title)
    if (!list.length) return res.status(400).json({ error: '模板至少需要一个检查项' })
    const row = await prisma.checkListTemplate.create({
      data: { userId, name: cleanName, scene: String(scene), items: list, builtin: false },
    })
    res.json({ item: row })
  } catch (e) { next(e) }
})

// PUT /api/checklists/templates/:id  改名称 / 检查项 (系统预置模板不可改)
router.put('/templates/:id', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const id = Number(req.params.id)
    const exist = await prisma.checkListTemplate.findFirst({ where: { id, userId, builtin: false } })
    if (!exist) return res.status(404).json({ error: '模板不存在、无权限修改或是系统预置模板' })
    const { name, scene, items } = req.body || {}
    const data = {}
    if (name !== undefined) {
      const n = String(name).trim()
      if (!n) return res.status(400).json({ error: '模板名称不能为空' })
      if (n.length > 20) return res.status(400).json({ error: '模板名称不能超过 20 个字' })
      data.name = n
    }
    if (scene !== undefined) data.scene = String(scene)
    if (items !== undefined) {
      const list = (Array.isArray(items) ? items : [])
        .map((i) => ({ title: String(i?.title || '').trim(), note: String(i?.note || '') }))
        .filter((i) => i.title)
      if (!list.length) return res.status(400).json({ error: '模板至少需要一个检查项' })
      data.items = list
    }
    const row = await prisma.checkListTemplate.update({ where: { id }, data })
    res.json({ item: row })
  } catch (e) { next(e) }
})

// DELETE /api/checklists/templates/:id  仅自建模板可删
router.delete('/templates/:id', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const id = Number(req.params.id)
    const exist = await prisma.checkListTemplate.findFirst({ where: { id, userId, builtin: false } })
    if (!exist) return res.status(404).json({ error: '模板不存在或无权删除' })
    await prisma.checkListTemplate.delete({ where: { id } })
    res.json({ ok: true })
  } catch (e) { next(e) }
})

// ---------- 清单 ----------

// GET /api/checklists?archived=0|1
router.get('/', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const archived = String(req.query.archived || '0') === '1'
    const rows = await prisma.checkList.findMany({
      where: { userId, archived },
      include: LIST_INCLUDE,
      orderBy: [{ updatedAt: 'desc' }],
    })
    res.json({ items: rows.map(withProgress) })
  } catch (e) { next(e) }
})

// POST /api/checklists  { title, scene?, note?, items?: string[] | [{title,note}], templateId? }
router.post('/', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const { title, scene = '', note = '', items = [], templateId } = req.body || {}
    const cleanTitle = String(title || '').trim()
    if (!cleanTitle) return res.status(400).json({ error: '清单名称不能为空' })

    let seed = (Array.isArray(items) ? items : [])
      .map((i) => (typeof i === 'string' ? { title: i } : i))
      .map((i) => ({ title: String(i?.title || '').trim(), note: String(i?.note || '') }))
      .filter((i) => i.title)

    if (!seed.length && templateId) {
      const tpl = await prisma.checkListTemplate.findFirst({
        where: { id: Number(templateId), OR: [{ builtin: true }, { userId }] },
      })
      if (tpl && Array.isArray(tpl.items)) {
        seed = tpl.items.map((i) => ({ title: String(i?.title || '').trim(), note: String(i?.note || '') })).filter((i) => i.title)
      }
    }

    const row = await prisma.checkList.create({
      data: {
        userId,
        title: cleanTitle,
        scene: String(scene),
        note: String(note),
        items: { create: seed.map((i, idx) => ({ title: i.title, note: i.note, sortOrder: idx })) },
      },
      include: LIST_INCLUDE,
    })
    res.json({ item: withProgress(row) })
  } catch (e) { next(e) }
})

// GET /api/checklists/:id
router.get('/:id', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const id = Number(req.params.id)
    const row = await prisma.checkList.findFirst({ where: { id, userId }, include: LIST_INCLUDE })
    if (!row) return res.status(404).json({ error: '清单不存在' })
    res.json({ item: withProgress(row) })
  } catch (e) { next(e) }
})

// PUT /api/checklists/:id  { title?, scene?, note?, archived? }
router.put('/:id', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const id = Number(req.params.id)
    const exist = await prisma.checkList.findFirst({ where: { id, userId } })
    if (!exist) return res.status(404).json({ error: '清单不存在' })
    const { title, scene, note, archived } = req.body || {}
    const data = {}
    if (title !== undefined) {
      const t = String(title).trim()
      if (!t) return res.status(400).json({ error: '清单名称不能为空' })
      data.title = t
    }
    if (scene !== undefined) data.scene = String(scene)
    if (note !== undefined) data.note = String(note)
    if (archived !== undefined) data.archived = !!archived
    const row = await prisma.checkList.update({ where: { id }, data, include: LIST_INCLUDE })
    res.json({ item: withProgress(row) })
  } catch (e) { next(e) }
})

// DELETE /api/checklists/:id
router.delete('/:id', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const id = Number(req.params.id)
    const exist = await prisma.checkList.findFirst({ where: { id, userId } })
    if (!exist) return res.status(404).json({ error: '清单不存在' })
    await prisma.checkListItem.deleteMany({ where: { listId: id } })
    await prisma.checkList.delete({ where: { id } })
    res.json({ ok: true })
  } catch (e) { next(e) }
})

// POST /api/checklists/:id/duplicate  复制一份新清单 (勾选状态重置)
router.post('/:id/duplicate', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const id = Number(req.params.id)
    const src = await prisma.checkList.findFirst({ where: { id, userId }, include: LIST_INCLUDE })
    if (!src) return res.status(404).json({ error: '清单不存在' })
    const row = await prisma.checkList.create({
      data: {
        userId,
        title: src.title + ' 副本',
        scene: src.scene,
        note: src.note,
        items: {
          create: src.items.map((i, idx) => ({ title: i.title, note: i.note, done: false, sortOrder: idx })),
        },
      },
      include: LIST_INCLUDE,
    })
    res.json({ item: withProgress(row) })
  } catch (e) { next(e) }
})

// ---------- 检查项 ----------

// POST /api/checklists/:id/items  { title, note? }
router.post('/:id/items', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const listId = Number(req.params.id)
    const list = await prisma.checkList.findFirst({ where: { id: listId, userId } })
    if (!list) return res.status(404).json({ error: '清单不存在' })
    const title = String((req.body || {}).title || '').trim()
    if (!title) return res.status(400).json({ error: '检查项不能为空' })
    if (title.length > 40) return res.status(400).json({ error: '检查项不能超过 40 个字' })
    const max = await prisma.checkListItem.findFirst({ where: { listId }, orderBy: { sortOrder: 'desc' } })
    const row = await prisma.checkListItem.create({
      data: { listId, title, note: String((req.body || {}).note || ''), sortOrder: (max?.sortOrder || 0) + 1 },
    })
    res.json({ item: row })
  } catch (e) { next(e) }
})

// PUT /api/checklists/items/:id  { title?, note?, done?, sortOrder? }
router.put('/items/:id', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const id = Number(req.params.id)
    const exist = await prisma.checkListItem.findFirst({ where: { id, list: { userId } } })
    if (!exist) return res.status(404).json({ error: '检查项不存在' })
    const { title, note, done, sortOrder } = req.body || {}
    const data = {}
    if (title !== undefined) {
      const t = String(title).trim()
      if (!t) return res.status(400).json({ error: '检查项不能为空' })
      data.title = t
    }
    if (note !== undefined) data.note = String(note)
    if (sortOrder !== undefined) data.sortOrder = Number(sortOrder) || 0
    if (done !== undefined) {
      data.done = !!done
      data.doneAt = done ? new Date() : null
    }
    const row = await prisma.checkListItem.update({ where: { id }, data })
    res.json({ item: row })
  } catch (e) { next(e) }
})

// DELETE /api/checklists/items/:id
router.delete('/items/:id', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const id = Number(req.params.id)
    const exist = await prisma.checkListItem.findFirst({ where: { id, list: { userId } } })
    if (!exist) return res.status(404).json({ error: '检查项不存在' })
    await prisma.checkListItem.delete({ where: { id } })
    res.json({ ok: true })
  } catch (e) { next(e) }
})

// POST /api/checklists/:id/check-all  { done: boolean }  一键全选 / 全不选
router.post('/:id/check-all', async (req, res, next) => {
  try {
    const userId = req.user.sub
    const listId = Number(req.params.id)
    const list = await prisma.checkList.findFirst({ where: { id: listId, userId } })
    if (!list) return res.status(404).json({ error: '清单不存在' })
    const done = !!(req.body || {}).done
    await prisma.checkListItem.updateMany({
      where: { listId },
      data: { done, doneAt: done ? new Date() : null },
    })
    const row = await prisma.checkList.findFirst({ where: { id: listId }, include: LIST_INCLUDE })
    res.json({ item: withProgress(row) })
  } catch (e) { next(e) }
})

export default router