const Database = require('better-sqlite3')
const path = require('path')
const fs = require('fs')
const crypto = require('crypto')

const dataDir = path.join(process.cwd(), 'data')
if (!fs.existsSync(dataDir)) fs.mkdirSync(dataDir, { recursive: true })
const dbPath = path.join(dataDir, 'rational_lock.db')
const db = new Database(dbPath)

db.exec(`
CREATE TABLE IF NOT EXISTS rl_users (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  username TEXT NOT NULL UNIQUE,
  password TEXT NOT NULL,
  created_at INTEGER NOT NULL
);
CREATE TABLE IF NOT EXISTS rl_sessions (
  token TEXT PRIMARY KEY,
  username TEXT NOT NULL,
  created_at INTEGER NOT NULL,
  expires_at INTEGER NOT NULL
);
CREATE TABLE IF NOT EXISTS rl_user_data (
  username TEXT PRIMARY KEY,
  items_json TEXT NOT NULL DEFAULT '[]',
  applications_json TEXT NOT NULL DEFAULT '[]',
  draft_json TEXT,
  updated_at INTEGER NOT NULL
);
CREATE INDEX IF NOT EXISTS idx_rl_sessions_user ON rl_sessions(username);
CREATE INDEX IF NOT EXISTS idx_rl_sessions_exp ON rl_sessions(expires_at);
`)

const now = () => Date.now()
const SESSION_MAX_AGE = 1 * 24 * 3600 * 1000
const COOKIE_NAME = 'rational_lock_sid'
const DEFAULT_USER = { username: 'admin_rl', password: process.env.LOCK_DEFAULT_PASSWORD || '' }

const parseCookie = cookieStr => {
  const out = {}
  String(cookieStr || '').split(/;\s*/).forEach(p => {
    const idx = p.indexOf('=')
    if (idx > 0) out[p.slice(0, idx)] = decodeURIComponent(p.slice(idx + 1))
  })
  return out
}

const ensureDefaultUser = () => {
  const row = db.prepare('SELECT username FROM rl_users WHERE username = ?').get(DEFAULT_USER.username)
  if (!row) {
    db.prepare('INSERT INTO rl_users (username, password, created_at) VALUES (?, ?, ?)').run(DEFAULT_USER.username, DEFAULT_USER.password, now())
  }
}

const cleanupSessions = () => {
  db.prepare('DELETE FROM rl_sessions WHERE expires_at <= ?').run(now())
}

const readDataOf = username => {
  const row = db.prepare('SELECT items_json, applications_json, draft_json FROM rl_user_data WHERE username = ?').get(username)
  if (!row) return { db: { items: [], applications: [] }, draft: null }
  let items = []
  let applications = []
  let draft = null
  try { items = JSON.parse(row.items_json || '[]') } catch {}
  try { applications = JSON.parse(row.applications_json || '[]') } catch {}
  try { draft = row.draft_json ? JSON.parse(row.draft_json) : null } catch {}
  return {
    db: {
      items: Array.isArray(items) ? items : [],
      applications: Array.isArray(applications) ? applications : []
    },
    draft: draft && typeof draft === 'object' ? draft : null
  }
}

const writeDataOf = (username, data) => {
  const dbData = data && data.db && typeof data.db === 'object' ? data.db : {}
  const items = Array.isArray(dbData.items) ? dbData.items : []
  const applications = Array.isArray(dbData.applications) ? dbData.applications : []
  const draft = data && data.draft && typeof data.draft === 'object' ? data.draft : null
  db.prepare(`
    INSERT INTO rl_user_data (username, items_json, applications_json, draft_json, updated_at)
    VALUES (?, ?, ?, ?, ?)
    ON CONFLICT(username) DO UPDATE SET
      items_json = excluded.items_json,
      applications_json = excluded.applications_json,
      draft_json = excluded.draft_json,
      updated_at = excluded.updated_at
  `).run(
    username,
    JSON.stringify(items),
    JSON.stringify(applications),
    draft ? JSON.stringify(draft) : null,
    now()
  )
}

const getSessionUser = req => {
  cleanupSessions()
  const cookies = parseCookie(req.headers.cookie || '')
  const token = String(cookies[COOKIE_NAME] || '')
  if (!token) return ''
  const row = db.prepare('SELECT username, expires_at FROM rl_sessions WHERE token = ?').get(token)
  if (!row) return ''
  if (Number(row.expires_at) <= now()) {
    db.prepare('DELETE FROM rl_sessions WHERE token = ?').run(token)
    return ''
  }
  return String(row.username || '')
}

const requireAuth = (req, res, next) => {
  const username = getSessionUser(req)
  if (!username) return res.status(401).json({ ok: false, error: 'unauthorized' })
  req.rlUser = username
  next()
}

const bindRoutes = app => {
  ensureDefaultUser()

  app.get('/api/rational_lock/health', (req, res) => {
    res.json({ ok: true })
  })

  app.get('/api/rational_lock/auth/local_creds', (req, res) => {
    try {
      const os = require('os')
      const userProfile = process.env.USERPROFILE || process.env.HOME || os.homedir()
      const candidates = [path.join(userProfile, 'Toolbox_local_creds.env.local')]
      const usersRoot = path.join(path.parse(userProfile).root, 'Users')
      try {
        if (fs.existsSync(usersRoot)) {
          fs.readdirSync(usersRoot).forEach(name => {
            const dir = path.join(usersRoot, name)
            if (dir !== userProfile && fs.existsSync(dir)) candidates.push(path.join(dir, 'Toolbox_local_creds.env.local'))
          })
        }
      } catch {}
      let content = null
      for (const p of candidates) { if (fs.existsSync(p)) { content = fs.readFileSync(p, 'utf-8'); break } }
      if (!content) return res.json({ ok: true, creds: null })
      const creds = {}
      content.split(/\r?\n/).forEach(line => {
        const t = line.trim()
        if (!t || t.startsWith('#')) return
        const idx = t.indexOf('=')
        if (idx > 0) creds[t.slice(0, idx).trim()] = t.slice(idx + 1).trim()
      })
      const serverToken = String(creds.TOOLBOX_LOCAL_CREDS_TOKEN || '')
      if (serverToken) {
        const clientToken = String(req.query.token || '')
        if (clientToken !== serverToken) return res.json({ ok: true, creds: null })
      }
      const u = creds.RL_USERNAME || ''
      const p = creds.RL_PASSWORD || ''
      if (!u && !p) return res.json({ ok: true, creds: null })
      res.json({ ok: true, creds: { username: u, password: p } })
    } catch { res.json({ ok: true, creds: null }) }
  })

  app.post('/api/rational_lock/auth/login', (req, res) => {
    const username = String((req.body && req.body.username) || '').trim()
    const password = String((req.body && req.body.password) || '')
    if (!username || !password) return res.status(400).json({ ok: false, error: 'invalid_credentials' })
    const row = db.prepare('SELECT username, password FROM rl_users WHERE username = ?').get(username)
    if (!row || String(row.password || '') !== password) return res.status(401).json({ ok: false, error: 'invalid_credentials' })
    const token = crypto.randomBytes(24).toString('hex')
    const createdAt = now()
    const expiresAt = createdAt + SESSION_MAX_AGE
    db.prepare('INSERT INTO rl_sessions (token, username, created_at, expires_at) VALUES (?, ?, ?, ?)').run(token, username, createdAt, expiresAt)
    res.cookie(COOKIE_NAME, token, { httpOnly: true, sameSite: 'lax', maxAge: SESSION_MAX_AGE })
    res.json({ ok: true, username })
  })

  app.post('/api/rational_lock/auth/logout', (req, res) => {
    const cookies = parseCookie(req.headers.cookie || '')
    const token = String(cookies[COOKIE_NAME] || '')
    if (token) db.prepare('DELETE FROM rl_sessions WHERE token = ?').run(token)
    res.cookie(COOKIE_NAME, '', { httpOnly: true, sameSite: 'lax', maxAge: 0 })
    res.json({ ok: true })
  })

  app.get('/api/rational_lock/auth/me', (req, res) => {
    const username = getSessionUser(req)
    if (!username) return res.status(401).json({ ok: false, error: 'unauthorized' })
    res.json({ ok: true, username })
  })

  app.get('/api/rational_lock/data', requireAuth, (req, res) => {
    const payload = readDataOf(req.rlUser)
    res.json({ ok: true, ...payload })
  })

  app.put('/api/rational_lock/data', requireAuth, (req, res) => {
    writeDataOf(req.rlUser, req.body || {})
    res.json({ ok: true })
  })
}

module.exports = { bindRoutes }