import express from 'express'
import http from 'http'
import { WebSocketServer } from 'ws'
import path from 'path'
import fs from 'fs'
import { fileURLToPath } from 'url'

const __dirname = path.dirname(fileURLToPath(import.meta.url))
const app = express()
const server = http.createServer(app)
const PORT = process.env.PORT || 3001

const MAPS_DIR    = path.join(__dirname, '..', 'maps')
const DOORS_FILE  = path.join(__dirname, '..', 'src', 'data', 'door-positions.json')
const BASEMAP_FILE = path.join(__dirname, '..', 'src', 'data', 'basemap.json')
const SIZES_FILE  = path.join(__dirname, '..', 'src', 'data', 'room-sizes.json')

// ── WebSocket (admin collab) ────────────────────────────────────────────────
const wss = new WebSocketServer({ server, path: '/ws/admin' })
const adminClients = new Set()

function readJSON(file, fallback) {
  try { return JSON.parse(fs.readFileSync(file, 'utf8')) } catch { return fallback }
}

function broadcast(sender, msg) {
  const str = JSON.stringify(msg)
  for (const client of adminClients) {
    if (client !== sender && client.readyState === 1) client.send(str)
  }
}

wss.on('connection', (ws) => {
  adminClients.add(ws)
  ws.send(JSON.stringify({
    type: 'init',
    doors: readJSON(DOORS_FILE, {}),
    basemap: readJSON(BASEMAP_FILE, []),
    sizes: readJSON(SIZES_FILE, {}),
  }))

  ws.on('message', (raw) => {
    try {
      const msg = JSON.parse(raw)
      if (msg.type === 'doors-save') {
        fs.writeFileSync(DOORS_FILE, JSON.stringify(msg.data, null, 2))
        broadcast(ws, { type: 'doors-update', data: msg.data })
      }
      if (msg.type === 'basemap-save') {
        fs.writeFileSync(BASEMAP_FILE, JSON.stringify(msg.data, null, 2))
        broadcast(ws, { type: 'basemap-update', data: msg.data })
      }
      if (msg.type === 'sizes-save') {
        fs.writeFileSync(SIZES_FILE, JSON.stringify(msg.data, null, 2))
        broadcast(ws, { type: 'sizes-update', data: msg.data })
      }
      if (msg.type === 'basemap-position-save') {
        const current = readJSON(BASEMAP_FILE, [])
        const next = current.map(entry => entry.id === msg.id ? { ...entry, position: msg.position } : entry)
        fs.writeFileSync(BASEMAP_FILE, JSON.stringify(next, null, 2))
        broadcast(ws, { type: 'basemap-update', data: next })
      }
    } catch {}
  })

  ws.on('close', () => adminClients.delete(ws))
})

// ── REST ────────────────────────────────────────────────────────────────────
function formatName(f) {
  return f.replace(/_/g,' ').replace(/\b\w/g,c=>c.toUpperCase())
    .replace(/\b1f\b/gi,'1F').replace(/\b2f\b/gi,'2F')
    .replace(/\bB1f\b/gi,'B1F').replace(/\bB2f\b/gi,'B2F')
    .replace(/\bRt\b/g,'Route').replace(/\bPokecenter\b/g,'Pokémon Center')
}

function scanRooms(dir, rooms = []) {
  for (const entry of fs.readdirSync(dir, { withFileTypes: true })) {
    const full = path.join(dir, entry.name)
    if (entry.isDirectory()) scanRooms(full, rooms)
    else if (entry.name.toLowerCase().endsWith('.png')) {
      const base = path.basename(entry.name, path.extname(entry.name)).toLowerCase()
      const rel  = path.relative(MAPS_DIR, full).replace(/\\/g, '/')
      const cat  = rel.split('/').slice(-2,-1)[0] ?? 'other'
      rooms.push({ id: base, name: formatName(base), image: `/maps/${rel}`, category: cat })
    }
  }
  return rooms
}

app.get('/api/rooms',      (_, res) => { try { res.json(scanRooms(MAPS_DIR)) } catch(e) { res.status(500).json({error:e.message}) } })
app.get('/api/doors',      (_, res) => res.json(readJSON(DOORS_FILE, {})))
app.get('/api/basemap',    (_, res) => res.json(readJSON(BASEMAP_FILE, [])))
app.get('/api/room-sizes', (_, res) => res.json(readJSON(SIZES_FILE, {})))

app.post('/api/doors',      express.json(), (req, res) => { try { fs.writeFileSync(DOORS_FILE,   JSON.stringify(req.body,null,2)); res.json({ok:true}) } catch(e){res.status(500).json({error:e.message})} })
app.post('/api/basemap',    express.json(), (req, res) => { try { fs.writeFileSync(BASEMAP_FILE, JSON.stringify(req.body,null,2)); res.json({ok:true}) } catch(e){res.status(500).json({error:e.message})} })
app.post('/api/room-sizes', express.json(), (req, res) => { try { fs.writeFileSync(SIZES_FILE,   JSON.stringify(req.body,null,2)); res.json({ok:true}) } catch(e){res.status(500).json({error:e.message})} })

app.use('/maps', express.static(MAPS_DIR))
app.use(express.static(path.join(__dirname, '..', 'dist')))
app.get('/{*path}', (_, res) => res.sendFile(path.join(__dirname, '..', 'dist', 'index.html')))

server.listen(PORT, () => console.log(`Pokemon Doors running on http://localhost:${PORT}`))