const { app, BrowserWindow, ipcMain } = require('electron')
const path = require('path')
const fs = require('fs')
const { SensorController } = require('./src/business/sensor-controller')
const { UsbSerialBridge } = require('./src/business/usb-serial-bridge')
const pkg = require('./package.json')

const cacheDir = app.getPath('userData')
const cacheFile = path.join(cacheDir, 'app-cache.json')
const fileRoot = path.join(cacheDir, 'files')

let mainWindow = null
let usbBridge = null
let sensorController = null

function ensureDir(dir) {
  try {
    if (!fs.existsSync(dir)) fs.mkdirSync(dir, { recursive: true })
  } catch {}
}

function readCache() {
  try {
    if (fs.existsSync(cacheFile)) return JSON.parse(fs.readFileSync(cacheFile, 'utf-8'))
  } catch {}
  return {}
}

function writeCache(data) {
  try {
    ensureDir(cacheDir)
    fs.writeFileSync(cacheFile, JSON.stringify(data, null, 2), 'utf-8')
  } catch {}
}

function resolveAppFile(inputPath) {
  const raw = String(inputPath || '').trim()
  if (!raw) return fileRoot
  if (path.isAbsolute(raw) && /^[a-zA-Z]:[\\/]/.test(raw)) return raw
  const relative = raw.replace(/^[/\\]+/, '')
  return path.join(fileRoot, relative)
}

function fileList(dir) {
  try {
    const target = resolveAppFile(dir)
    if (!fs.existsSync(target)) return ''
    const stat = fs.statSync(target)
    if (stat.isFile()) return target
    return fs.readdirSync(target).map(name => path.join(target, name)).join('\n')
  } catch {
    return ''
  }
}

function emit(channel, ...args) {
  if (mainWindow && !mainWindow.isDestroyed()) {
    mainWindow.webContents.send(channel, ...args)
  }
}

function lastSensorValue(id, opId) {
  if (!sensorController) return null
  const device = sensorController.devices.find(d => d.id === id) ||
    sensorController.devices.find(d => d.sensor === id) ||
    sensorController.devices.find(d => d.sensor === String(id || '').split(':')[0])
  if (!device) return null
  return sensorController.lastValues.get(`${device.sensor}:${opId}`) ?? null
}

function createSensorController() {
  sensorController = new SensorController({
    onValue: data => emit('sensor-data', data),
    onDeviceAttached: device => emit('sensor-attached', { id: device.id, name: device.name }),
    onDeviceDetached: device => emit('sensor-detached', { id: device.id, name: device.name }),
    onLog: (level, msg) => emit('sensor-log', { level, msg })
  })
  sensorController.refresh().catch(err => console.error('[sensor] refresh failed:', err.message))
}

function createWindow() {
  mainWindow = new BrowserWindow({
    width: 1280,
    height: 800,
    fullscreen: false,
    webPreferences: {
      preload: path.join(__dirname, 'preload.js'),
      contextIsolation: true,
      nodeIntegration: false,
      sandbox: false
    }
  })

  createSensorController()
  usbBridge = new UsbSerialBridge(mainWindow, {
    onDeviceDiscovered: () => {
      if (sensorController) sensorController.refresh().catch(() => {})
    }
  })

  mainWindow.loadFile(path.join(__dirname, 'dist', 'index.html'))
}

function registerAppIpc() {
  ipcMain.on('app-clear-cache-sync', (event) => {
    writeCache({})
    if (mainWindow && !mainWindow.isDestroyed()) mainWindow.reload()
    event.returnValue = true
  })

  ipcMain.on('app-version-code-sync', (event) => {
    const major = Number(String(pkg.version || '1').split('.')[0]) || 1
    event.returnValue = major
  })

  ipcMain.on('get-cache-sync', (event, key) => {
    const cache = readCache()
    event.returnValue = key ? (cache[key] ?? null) : JSON.stringify(cache)
  })

  ipcMain.on('set-cache-sync', (event, key, value) => {
    const cache = readCache()
    cache[key] = value
    writeCache(cache)
    event.returnValue = true
  })

  ipcMain.handle('get-cache', (_event, key) => {
    const cache = readCache()
    return key ? (cache[key] ?? null) : cache
  })

  ipcMain.handle('set-cache', (_event, key, value) => {
    const cache = readCache()
    cache[key] = value
    writeCache(cache)
    return true
  })

  ipcMain.on('app-offline-page', () => emit('app-page-mode', 'offline'))
  ipcMain.on('app-online-page', () => emit('app-page-mode', 'online'))

  ipcMain.on('app-file-list-sync', (event, dir) => {
    event.returnValue = fileList(dir)
  })

  ipcMain.on('app-file-write-string', (event, filePath, content, token) => {
    const target = resolveAppFile(filePath)
    fs.promises.mkdir(path.dirname(target), { recursive: true })
      .then(() => fs.promises.writeFile(target, String(content ?? ''), 'utf-8'))
      .then(() => event.sender.send('app-file-write-callback', token, target, true, ''))
      .catch(err => event.sender.send('app-file-write-callback', token, target, false, err.message))
  })

  ipcMain.on('app-file-read-string', (event, filePath, token) => {
    const target = resolveAppFile(filePath)
    fs.promises.readFile(target, 'utf-8')
      .then(content => event.sender.send('app-file-read-callback', token, target, content))
      .catch(() => event.sender.send('app-file-read-callback', token, target, null))
  })

  ipcMain.on('app-file-delete', (event, filePath, token) => {
    const target = resolveAppFile(filePath)
    fs.promises.unlink(target)
      .then(() => event.sender.send('app-file-delete-callback', token, target, true))
      .catch(() => event.sender.send('app-file-delete-callback', token, target, false))
  })

  ipcMain.on('app-export-file', (event, filename, content, token) => {
    const target = resolveAppFile(filename || `export-${Date.now()}.txt`)
    fs.promises.mkdir(path.dirname(target), { recursive: true })
      .then(() => fs.promises.writeFile(target, String(content ?? ''), 'utf-8'))
      .then(() => event.sender.send('app-file-write-callback', token || filename, target, true, ''))
      .catch(err => event.sender.send('app-file-write-callback', token || filename, target, false, err.message))
  })
}

function registerSensorIpc() {
  ipcMain.on('app-sensor-open-sync', (event) => {
    if (sensorController) sensorController.open().catch(() => {})
    event.returnValue = true
  })
  ipcMain.on('app-sensor-close-sync', (event) => {
    event.returnValue = sensorController ? sensorController.close() : true
  })
  ipcMain.on('app-sensor-is-open-sync', (event) => {
    event.returnValue = sensorController ? sensorController.isOpen : false
  })

  ipcMain.on('sensor-init-all-sync', (event) => {
    if (sensorController) sensorController.initAll().catch(() => {})
    event.returnValue = true
  })
  ipcMain.on('sensor-flush-sync', (event) => {
    if (sensorController) sensorController.refresh().catch(() => {})
    event.returnValue = true
  })
  ipcMain.on('sensor-list-sync', (event) => {
    event.returnValue = sensorController ? sensorController.list() : []
  })
  ipcMain.on('sensor-init-sync', (event, id) => {
    event.returnValue = sensorController ? sensorController.init(id) : false
  })
  ipcMain.on('sensor-open-sync', (event) => {
    if (sensorController) sensorController.open().catch(() => {})
    event.returnValue = true
  })
  ipcMain.on('sensor-close-sync', (event) => {
    event.returnValue = sensorController ? sensorController.close() : true
  })
  ipcMain.on('sensor-operation-sync', (event, id, opId) => {
    const cached = lastSensorValue(id, opId)
    if (sensorController) {
      sensorController.operation(id, opId).catch(() => {})
    }
    event.returnValue = cached
  })
  ipcMain.on('sensor-operation-async', (event, id, opId, args) => {
    if (!sensorController) {
      event.sender.send('sensor-operation-callback', id, opId, null)
      return
    }
    sensorController.operation(id, opId, args)
      .then(result => event.sender.send('sensor-operation-callback', id, opId, result))
      .catch(err => event.sender.send('sensor-operation-callback', id, opId, err.message))
  })
}

function registerLocationAndBluetoothIpc() {
  ipcMain.on('app-location-is-support-sync', (event) => { event.returnValue = false })
  ipcMain.on('app-location-is-open-sync', (event) => { event.returnValue = false })
  ipcMain.on('app-location-open', (event) => { event.sender.send('app-location-opened', 1) })
  ipcMain.on('app-location-close', () => {})

  ipcMain.on('bluetooth-device-select', (event, namePrefix) => {
    event.sender.send('bluetooth-device-selected', 'false', namePrefix || '')
  })
  ipcMain.on('bluetooth-device-open', (event, mac) => {
    event.sender.send('bluetooth-device-opened', 'false', mac || '')
    event.sender.send('bluetooth-device-state-changed', mac || '', 'UNSUPPORTED')
  })
  ipcMain.on('bluetooth-device-write', () => {})
  ipcMain.on('bluetooth-device-close', () => {})
}

function registerIpc() {
  registerAppIpc()
  registerSensorIpc()
  registerLocationAndBluetoothIpc()
}

app.whenReady().then(() => {
  registerIpc()
  ensureDir(fileRoot)
  createWindow()

  app.on('before-quit', () => {
    if (sensorController) sensorController.close()
    if (usbBridge) usbBridge.disconnectAll()
  })
})

app.on('window-all-closed', () => {
  if (process.platform !== 'darwin') app.quit()
})