const {
  app,
  BrowserWindow,
  Tray,
  Menu,
  Notification,
  ipcMain,
  shell,
  dialog,
  nativeImage,
} = require('electron')
const fs = require('node:fs')
const path = require('node:path')

const APP_ID = 'top.fmcraft.chat.desktop'
const DEFAULT_URL = 'https://chat.fmcraft.top'
const DEFAULT_CONFIG = {
  url: DEFAULT_URL,
  windows: true,
  flash: true,
  sound: true,
}

const iconPath = path.join(__dirname, 'assets', 'icon.png')
const trayIconPath = path.join(__dirname, 'assets', 'tray.png')

let config = { ...DEFAULT_CONFIG }
let configPath = ''
let mainWindow = null
let settingsWindow = null
let tray = null
let audioWindow = null
let audioReady = false
let pendingSound = false
let appIcon = null

app.commandLine.appendSwitch('autoplay-policy', 'no-user-gesture-required')
app.setName('FMCRAFT Chat')

function defaultConfigText() {
  return [
    '[app]',
    `url=${DEFAULT_URL}`,
    '',
    '[notifications]',
    'windows=true',
    'flash=true',
    'sound=true',
    '',
  ].join('\n')
}

function parseIni(text) {
  const result = {}
  let section = ''
  for (const raw of text.split(/\r?\n/)) {
    const line = raw.trim()
    if (!line || line.startsWith(';') || line.startsWith('#')) continue
    const sectionMatch = line.match(/^\[([^\]]+)\]$/)
    if (sectionMatch) {
      section = sectionMatch[1].trim()
      if (!result[section]) result[section] = {}
      continue
    }
    const index = line.indexOf('=')
    if (index === -1) continue
    const key = line.slice(0, index).trim()
    const value = line
      .slice(index + 1)
      .trim()
      .replace(/^"(.*)"$/, '$1')
    if (!result[section]) result[section] = {}
    result[section][key] = value
  }
  return result
}

function boolValue(value, fallback) {
  if (value === undefined || value === null || value === '') return fallback
  return ['1', 'true', 'yes', 'on'].includes(String(value).toLowerCase())
}

function resolveConfigPath() {
  const portableDir = process.env.PORTABLE_EXECUTABLE_DIR
  const localDir = portableDir || (app.isPackaged ? path.dirname(app.getPath('exe')) : __dirname)
  const localPath = path.join(localDir, 'config.ini')
  try {
    if (!fs.existsSync(localPath)) fs.writeFileSync(localPath, defaultConfigText(), 'utf8')
    fs.accessSync(localPath, fs.constants.W_OK)
    return localPath
  } catch {
    // Program Files 等只读目录：回退到用户数据目录，设置页会显示实际路径。
    const fallbackDir = app.getPath('userData')
    fs.mkdirSync(fallbackDir, { recursive: true })
    const fallbackPath = path.join(fallbackDir, 'config.ini')
    if (!fs.existsSync(fallbackPath)) {
      fs.writeFileSync(fallbackPath, defaultConfigText(), 'utf8')
    }
    return fallbackPath
  }
}

function loadConfig() {
  configPath = resolveConfigPath()
  let raw = {}
  try {
    raw = parseIni(fs.readFileSync(configPath, 'utf8'))
  } catch {
    raw = {}
  }
  const appSection = raw.app || {}
  const notifications = raw.notifications || {}
  config = {
    url: (appSection.url || DEFAULT_URL).trim() || DEFAULT_URL,
    windows: boolValue(notifications.windows, true),
    flash: boolValue(notifications.flash, true),
    sound: boolValue(notifications.sound, true),
  }
}

function saveConfig() {
  const text = [
    '[app]',
    `url=${config.url}`,
    '',
    '[notifications]',
    `windows=${config.windows ? 'true' : 'false'}`,
    `flash=${config.flash ? 'true' : 'false'}`,
    `sound=${config.sound ? 'true' : 'false'}`,
    '',
  ].join('\n')
  try {
    fs.writeFileSync(configPath, text, 'utf8')
  } catch (err) {
    dialog.showErrorBox('保存配置失败', String(err && err.message ? err.message : err))
  }
}

function isSameSite(url) {
  try {
    return new URL(url).origin === new URL(config.url).origin
  } catch {
    return false
  }
}

function createMainWindow() {
  mainWindow = new BrowserWindow({
    width: 1280,
    height: 820,
    minWidth: 960,
    minHeight: 600,
    title: 'FMCRAFT Chat',
    icon: appIcon || iconPath,
    backgroundColor: '#0b0e14',
    webPreferences: {
      preload: path.join(__dirname, 'preload.js'),
      contextIsolation: true,
      nodeIntegration: false,
      sandbox: false,
      spellcheck: true,
    },
  })

  mainWindow.loadURL(config.url).catch((err) => {
    dialog.showErrorBox(
      '无法打开 FMCRAFT Chat',
      `请检查 config.ini 中的页面地址是否可访问。\n\n${String(err && err.message ? err.message : err)}`
    )
  })

  mainWindow.on('focus', () => {
    if (mainWindow && !mainWindow.isDestroyed()) mainWindow.flashFrame(false)
  })
  mainWindow.on('closed', () => {
    mainWindow = null
  })

  // 站内链接留在应用内，外部链接交给系统浏览器。
  mainWindow.webContents.setWindowOpenHandler(({ url }) => {
    shell.openExternal(url)
    return { action: 'deny' }
  })
  mainWindow.webContents.on('will-navigate', (event, url) => {
    if (url.startsWith('http') && !isSameSite(url)) {
      event.preventDefault()
      shell.openExternal(url)
    }
  })
}

function showMainWindow() {
  if (!mainWindow || mainWindow.isDestroyed()) {
    createMainWindow()
    return
  }
  if (mainWindow.isMinimized()) mainWindow.restore()
  mainWindow.show()
  mainWindow.focus()
}

function createAudioWindow() {
  audioWindow = new BrowserWindow({
    show: false,
    skipTaskbar: true,
    webPreferences: {
      contextIsolation: true,
      nodeIntegration: false,
      backgroundThrottling: false,
    },
  })
  audioWindow.loadFile(path.join(__dirname, 'audio.html'))
  audioWindow.webContents.on('did-finish-load', () => {
    audioReady = true
    if (pendingSound) {
      pendingSound = false
      playSound(true)
    }
  })
}

function playSound(enabled = config.sound) {
  if (!enabled) return
  if (!audioReady || !audioWindow || audioWindow.isDestroyed()) {
    pendingSound = true
    return
  }
  audioWindow.webContents
    .executeJavaScript('window.playNotification && window.playNotification()')
    .catch(() => {})
}

function showWindowsNotification(title, body) {
  // Windows 7/8 没有 Toast；便携版在 Windows 10/11 上也不一定有开始菜单快捷方式。
  // 统一使用托盘气泡，保证 Windows 7 及以上都能收到提醒。
  if (process.platform === 'win32' && tray) {
    tray.displayBalloon({
      title,
      content: body,
      icon: appIcon || iconPath,
      noSound: true,
      respectQuietTime: true,
    })
    return
  }
  if (!Notification.isSupported()) return
  const notification = new Notification({
    title,
    body,
    icon: appIcon || iconPath,
    silent: true,
  })
  notification.on('click', showMainWindow)
  notification.show()
}

function handleDesktopNotification(payload, override) {
  const options = override ? { ...config, ...override } : config
  const title = String(payload && payload.title ? payload.title : 'FMCRAFT Chat').slice(0, 120)
  const body = String(payload && payload.body ? payload.body : '').slice(0, 500)

  if (options.windows) showWindowsNotification(title, body)
  if (options.flash && mainWindow && !mainWindow.isDestroyed() && !mainWindow.isFocused()) {
    mainWindow.flashFrame(true)
  }
  if (options.sound) playSound(true)
}

function updateTrayMenu() {
  if (!tray || tray.isDestroyed()) return
  tray.setContextMenu(
    Menu.buildFromTemplate([
      { label: '显示 FMCRAFT Chat', click: showMainWindow },
      { label: '通知设置…', click: openSettingsWindow },
      { type: 'separator' },
      {
        label: 'Windows 消息通知',
        type: 'checkbox',
        checked: config.windows,
        click: (item) => {
          config.windows = !!item.checked
          saveConfig()
        },
      },
      {
        label: '任务栏闪烁',
        type: 'checkbox',
        checked: config.flash,
        click: (item) => {
          config.flash = !!item.checked
          saveConfig()
        },
      },
      {
        label: '音效播放',
        type: 'checkbox',
        checked: config.sound,
        click: (item) => {
          config.sound = !!item.checked
          saveConfig()
        },
      },
      { type: 'separator' },
      { label: '退出', click: () => app.quit() },
    ])
  )
}

function createTray() {
  try {
    const image = nativeImage.createFromPath(trayIconPath)
    tray = new Tray(image)
    tray.setToolTip('FMCRAFT Chat')
    tray.on('double-click', showMainWindow)
    tray.on('click', showMainWindow)
    tray.on('balloon-click', showMainWindow)
    updateTrayMenu()
  } catch (err) {
    console.warn('无法创建托盘图标：', err)
  }
}

function createMenu() {
  const template = [
    {
      label: '文件',
      submenu: [
        { label: '通知设置…', accelerator: 'CmdOrCtrl+,', click: openSettingsWindow },
        {
          label: '打开配置文件',
          click: () => {
            shell.openPath(configPath).then((error) => {
              if (error) shell.showItemInFolder(configPath)
            })
          },
        },
        { type: 'separator' },
        { role: 'quit', label: '退出' },
      ],
    },
    {
      label: '查看',
      submenu: [
        { role: 'reload', label: '刷新' },
        { role: 'forceReload', label: '强制刷新' },
        { role: 'toggleDevTools', label: '开发者工具' },
        { type: 'separator' },
        { role: 'resetZoom', label: '实际大小' },
        { role: 'zoomIn', label: '放大' },
        { role: 'zoomOut', label: '缩小' },
        { role: 'togglefullscreen', label: '全屏' },
      ],
    },
    {
      label: '帮助',
      submenu: [
        {
          label: '关于 FMCRAFT Chat',
          click: () => {
            dialog.showMessageBox({
              type: 'info',
              title: '关于 FMCRAFT Chat',
              message: 'FMCRAFT Chat 桌面版',
              detail: `版本 ${app.getVersion()}\n适用于 Windows 7 及以上。\n\n配置文件：${configPath}`,
              buttons: ['确定'],
            })
          },
        },
      ],
    },
  ]
  Menu.setApplicationMenu(Menu.buildFromTemplate(template))
}

function openSettingsWindow() {
  if (settingsWindow && !settingsWindow.isDestroyed()) {
    settingsWindow.show()
    settingsWindow.focus()
    return
  }
  settingsWindow = new BrowserWindow({
    width: 500,
    height: 470,
    minWidth: 460,
    minHeight: 430,
    resizable: true,
    minimizable: false,
    maximizable: false,
    title: 'FMCRAFT Chat 通知设置',
    icon: appIcon || iconPath,
    parent: mainWindow || undefined,
    autoHideMenuBar: true,
    webPreferences: {
      preload: path.join(__dirname, 'settings-preload.js'),
      contextIsolation: true,
      nodeIntegration: false,
      sandbox: false,
    },
  })
  settingsWindow.setMenuBarVisibility(false)
  settingsWindow.loadFile(path.join(__dirname, 'settings.html'))
  settingsWindow.on('closed', () => {
    settingsWindow = null
  })
}

function registerIpc() {
  ipcMain.on('desktop:notify', (_event, payload) => {
    if (!payload || typeof payload !== 'object') return
    handleDesktopNotification(payload)
  })

  ipcMain.handle('settings:get', () => ({ ...config, configPath }))

  ipcMain.handle('settings:save', (_event, values) => {
    if (values && typeof values === 'object') {
      config.windows = !!values.windows
      config.flash = !!values.flash
      config.sound = !!values.sound
      saveConfig()
      updateTrayMenu()
    }
    return { ...config, configPath }
  })

  ipcMain.handle('settings:test', (_event, values) => {
    const options = values && typeof values === 'object' ? values : config
    handleDesktopNotification(
      {
        title: 'FMCRAFT Chat 通知测试',
        body: '如果你看到这条通知，说明桌面通知工作正常。',
      },
      options
    )
    return { ok: true }
  })

  ipcMain.on('settings:open-config', () => {
    shell.openPath(configPath).then((error) => {
      if (error) shell.showItemInFolder(configPath)
    })
  })
}

app.whenReady().then(() => {
  if (process.platform === 'win32') app.setAppUserModelId(APP_ID)
  loadConfig()
  appIcon = nativeImage.createFromPath(iconPath)
  registerIpc()
  createMainWindow()
  createMenu()
  createTray()
  createAudioWindow()

  app.on('activate', () => {
    if (!mainWindow) createMainWindow()
  })
})

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

app.on('before-quit', () => {
  if (audioWindow && !audioWindow.isDestroyed()) audioWindow.destroy()
})