piano-midi-monitor/src/main/index.ts

import { app, shell, BrowserWindow, ipcMain } from 'electron'
import { join } from 'path'
import { readFile, stat, writeFile } from "fs/promises";
import { electronApp, optimizer, is } from '@electron-toolkit/utils'
import icon from '../../resources/icon.png?asset'

interface Config {
  range: string
  queryDeviceKey: string
  scaleFactor: string
}

const defaultConfig: Config = {
  range: '21|108',
  queryDeviceKey: '',
  scaleFactor: '1'
}

const configPath = './config.json'
const naturalKeyWidth = 20
const pedalBoardWidth = 239
const height = 200

const getNaturalKeys = (range: string): number => {
  const [startKeyRaw, endKeyRaw] = range.split('|')
  const startKey = Number(startKeyRaw)
  const endKey = Number(endKeyRaw)
  let naturalKeys = 0
  for (let i = startKey; i <= endKey; i += 1) {
    switch (i % 12) {
      case 0:
      case 2:
      case 4:
      case 5:
      case 7:
      case 9:
      case 11:
        naturalKeys += 1
        break
      default:
        break
    }
  }
  return naturalKeys
}

function createWindow(config: Config): void {
  // Create the browser window.
  const naturalKeys = getNaturalKeys(config.range)
  const width = naturalKeys * naturalKeyWidth + pedalBoardWidth
  const mainWindow = new BrowserWindow({
    width,
    height,
    show: false,
    autoHideMenuBar: true,
    ...(process.platform === 'linux' ? { icon } : {}),
    webPreferences: {
      preload: join(__dirname, '../preload/index.js'),
      sandbox: false,
      devTools: is.dev
    },
    maximizable: is.dev,
    minimizable: false,
    maxHeight: is.dev ? undefined : height,
    minHeight: is.dev ? undefined : height,
    minWidth: is.dev ? undefined : width,
    maxWidth: is.dev ? undefined : width,
    fullscreenable: false,
    resizable: is.dev
  })

  mainWindow.on('ready-to-show', () => {
    mainWindow.show()
  })

  mainWindow.webContents.setWindowOpenHandler((details) => {
    void shell.openExternal(details.url)
    return { action: 'deny' }
  })

  let search: URLSearchParams
  if (is.dev && process.env['ELECTRON_RENDERER_URL']) {
    const url = new URL(process.env['ELECTRON_RENDERER_URL'])
    search = new URLSearchParams(url.searchParams)
    Object.entries(config).forEach(([key, value]) => {
      search.set(key, value)
    })
    url.search = search.toString()
    void mainWindow.loadURL(url.toString())
    return
  }

  search = new URLSearchParams()
  Object.entries(config).forEach(([key, value]) => {
    search.set(key, value)
  })
  void mainWindow.loadFile(join(__dirname, '../renderer/index.html'), {
    search: search.toString()
  })
}

app.whenReady().then(async () => {
  const effectiveConfig = { ...defaultConfig }
  try {
    const theStat = await stat(configPath)
    if (theStat.isDirectory()) {
      return
    }
    const jsonRaw = await readFile(configPath, 'utf-8')
    const json = JSON.parse(jsonRaw)
    Object.entries(json).forEach(([key, value]) => {
      effectiveConfig[key] = value
    })
  } catch {
    await writeFile(configPath, JSON.stringify(defaultConfig))
  }

  electronApp.setAppUserModelId('sh.modal.pianomidimonitor')

  app.on('browser-window-created', (_, window) => {
    optimizer.watchWindowShortcuts(window)
  })

  ipcMain.on('querydevicekeychange', async (_event, value) => {
    effectiveConfig.queryDeviceKey = value
    await writeFile(configPath, JSON.stringify(effectiveConfig))
  })

  ipcMain.on('scalefactorchange', async (_event, value) => {
    effectiveConfig.scaleFactor = value
    await writeFile(configPath, JSON.stringify(effectiveConfig))
  })

  ipcMain.on('rangechange', async (event, value) => {
    effectiveConfig.range = value
    await writeFile(configPath, JSON.stringify(effectiveConfig))
    const webContents = event.sender
    const win = BrowserWindow.fromWebContents(webContents)
    if (!win) {
      return
    }
    win.close()
    createWindow(effectiveConfig)
  })

  createWindow(effectiveConfig)

  app.on('activate', function () {
    if (BrowserWindow.getAllWindows().length === 0) {
      createWindow(effectiveConfig)
    }
  })
})

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