import { app } from 'electron'
import path from 'path'
import fs from 'fs'
import log from 'electron-log'

const RUNTIME_CONFIG_FILES = ['CapSettings.json'] as const
const DEFAULT_PRINT_TASKS = path.join('C:', 'PrintTasks')

const DEFAULT_CAP_SETTINGS = `{
  "printerList": [],
  "Img": [],
  "Text": []
}
`

export function getNativeDir(): string {
  if (app.isPackaged) {
    return path.join(process.resourcesPath, 'native')
  }
  return path.join(app.getAppPath(), 'resources', 'native')
}

export function getProcessExecDir(): string {
  return path.dirname(process.execPath)
}

function ensureBundledConfig(nativeDir: string): void {
  fs.mkdirSync(nativeDir, { recursive: true })
  for (const name of RUNTIME_CONFIG_FILES) {
    const filePath = path.join(nativeDir, name)
    if (!fs.existsSync(filePath)) {
      fs.writeFileSync(filePath, DEFAULT_CAP_SETTINGS, 'utf8')
      log.info(`Created default native config: ${filePath}`)
    }
  }
}

function deployConfigFile(src: string, destDir: string): void {
  const dest = path.join(destDir, path.basename(src))
  try {
    fs.mkdirSync(destDir, { recursive: true })
    if (!fs.existsSync(dest)) {
      fs.copyFileSync(src, dest)
      log.debug(`Deployed ${path.basename(src)} -> ${dest}`)
      return
    }
    const srcStat = fs.statSync(src)
    const destStat = fs.statSync(dest)
    if (srcStat.mtimeMs > destStat.mtimeMs) {
      fs.copyFileSync(src, dest)
      log.debug(`Updated ${path.basename(src)} -> ${dest}`)
    }
  } catch (e) {
    log.warn(`Deploy ${path.basename(src)} to ${destDir} failed`, e)
  }
}

function deployRuntimeConfigs(nativeDir: string): void {
  const deployDirs = new Set<string>([
    nativeDir,
    getProcessExecDir(),
    DEFAULT_PRINT_TASKS,
    path.join(app.getPath('userData'), 'Cardsoon', 'runtime')
  ])

  for (const name of RUNTIME_CONFIG_FILES) {
    const src = path.join(nativeDir, name)
    if (!fs.existsSync(src)) continue
    deployDirs.forEach((dir) => deployConfigFile(src, dir))
  }

  try {
    fs.mkdirSync(DEFAULT_PRINT_TASKS, { recursive: true })
  } catch (e) {
    log.warn(`Cannot create ${DEFAULT_PRINT_TASKS}`, e)
  }
}

export function setupNativeWorkingDir(): void {
  const nativeDir = getNativeDir()
  if (!fs.existsSync(path.join(nativeDir, 'workDll.dll'))) {
    throw new Error(`Native DLL directory not found or incomplete: ${nativeDir}`)
  }
  ensureBundledConfig(nativeDir)
  deployRuntimeConfigs(nativeDir)
  const execDir = getProcessExecDir()
  const pathHead = [nativeDir, execDir].join(path.delimiter)
  if (!process.env.PATH?.toLowerCase().includes(nativeDir.toLowerCase())) {
    process.env.PATH = `${pathHead}${path.delimiter}${process.env.PATH || ''}`
  }
  try {
    process.chdir(execDir)
  } catch (e) {
    log.warn(`chdir to ${execDir} failed`, e)
  }
  log.debug(`Native DLL search path: ${nativeDir}; cwd=${process.cwd()}`)
}