import { spawn } from 'child_process'
import dotenv from 'dotenv'
import { existsSync, readFileSync, writeFileSync } from 'fs'
import { applyEdits, modify } from 'jsonc-parser'
import path from 'path'

type TargetEnvironment = 'luoxin' | 'pre' | 'prod'

interface EnvironmentConfig {
  appid: string
  baseApi: string
  envFile: string
  label: string
  viteMode: string
  viteModeValue: string
}

const ROOT_DIR = path.resolve(__dirname, '..')
const MANIFEST_PATH = path.resolve(ROOT_DIR, 'src/manifest.json')
const UNI_CLI_PATH = path.resolve(ROOT_DIR, 'node_modules/@dcloudio/vite-plugin-uni/bin/uni.js')
const BUILD_OUTPUT_DIR = path.resolve(ROOT_DIR, 'dist/build/mp-weixin')

const ORIGINAL_APPID = 'wxd03398e1bff2b241'
const LUOXIN_APPID = 'wx2a5a7f417981f250'

const ENVIRONMENTS: Record<TargetEnvironment, EnvironmentConfig> = {
  luoxin: {
    appid: LUOXIN_APPID,
    baseApi: 'https://luoxin.yaoyi.net',
    envFile: '.env.production_LUOXIN',
    label: '罗欣',
    viteMode: 'production_LUOXIN',
    viteModeValue: 'production_luoxin',
  },
  pre: {
    appid: ORIGINAL_APPID,
    baseApi: 'https://preapi.yaoyi.net',
    envFile: '.env.pre',
    label: '预发布',
    viteMode: 'pre',
    viteModeValue: 'production_pre',
  },
  prod: {
    appid: ORIGINAL_APPID,
    baseApi: 'https://api.yaoyi.net',
    envFile: '.env.production',
    label: '正式',
    viteMode: 'production',
    viteModeValue: 'production',
  },
}

const TARGETS: TargetEnvironment[] = ['luoxin', 'pre', 'prod']

const fail = (message: string): never => {
  throw new Error(message)
}

const parseTarget = (value: string | undefined): TargetEnvironment => {
  const target = TARGETS.find((item) => item === value)

  if (!target) {
    throw new Error(`环境必须是：${TARGETS.join(' / ')}`)
  }

  return target
}

const loadEnvironment = (target: TargetEnvironment): NodeJS.ProcessEnv => {
  const config = ENVIRONMENTS[target]
  const envPath = path.resolve(ROOT_DIR, config.envFile)

  if (!existsSync(envPath)) {
    fail(`环境文件不存在：${config.envFile}`)
  }

  const parsedEnv = dotenv.parse(readFileSync(envPath, 'utf8'))
  const expectedValues: Record<string, string> = {
    VITE_BASE_API: config.baseApi,
    VITE_MODE: config.viteModeValue,
    VITE_WX_APPID: config.appid,
  }

  for (const [key, expectedValue] of Object.entries(expectedValues)) {
    if (parsedEnv[key] !== expectedValue) {
      fail(
        `${config.envFile} 中的 ${key} 配置错误：期望 ${expectedValue}，实际 ${parsedEnv[key] || '未配置'}`
      )
    }
  }

  return {
    ...process.env,
    ...parsedEnv,
  }
}

const injectManifestAppid = (manifestSource: string, appid: string): string => {
  const edits = modify(manifestSource, ['mp-weixin', 'appid'], appid, {
    formattingOptions: {
      insertSpaces: true,
      tabSize: 2,
    },
  })

  return applyEdits(manifestSource, edits)
}

const runUniBuild = async (
  target: TargetEnvironment,
  processEnv: NodeJS.ProcessEnv
): Promise<void> => {
  const config = ENVIRONMENTS[target]

  await new Promise<void>((resolve, reject) => {
    const childProcess = spawn(
      process.execPath,
      [UNI_CLI_PATH, 'build', '-p', 'mp-weixin', '--mode', config.viteMode],
      {
        cwd: ROOT_DIR,
        env: processEnv,
        stdio: 'inherit',
      }
    )

    childProcess.once('error', reject)
    childProcess.once('exit', (code, signal) => {
      if (code === 0) {
        resolve()
        return
      }

      reject(
        new Error(
          signal ? `uni-app 进程被信号 ${signal} 终止` : `uni-app 进程退出，错误码：${code}`
        )
      )
    })
  })
}

const validateBuildOutput = (expectedAppid: string): void => {
  const projectConfigPath = path.resolve(BUILD_OUTPUT_DIR, 'project.config.json')

  if (!existsSync(projectConfigPath)) {
    fail(`构建产物不存在：${projectConfigPath}`)
  }

  const projectConfig = JSON.parse(readFileSync(projectConfigPath, 'utf8')) as {
    appid?: string
  }

  if (projectConfig.appid !== expectedAppid) {
    fail(`构建产物 AppID 校验失败：期望 ${expectedAppid}，实际 ${projectConfig.appid || '未配置'}`)
  }
}

const main = async (): Promise<void> => {
  const target = parseTarget(process.argv[2])
  const config = ENVIRONMENTS[target]
  const processEnv = loadEnvironment(target)
  const originalManifest = readFileSync(MANIFEST_PATH, 'utf8')

  console.log(`\n[环境] ${config.label} (${target})`)
  console.log(`[接口] ${config.baseApi}`)
  console.log(`[AppID] ${config.appid}`)

  writeFileSync(MANIFEST_PATH, injectManifestAppid(originalManifest, config.appid), 'utf8')

  try {
    await runUniBuild(target, processEnv)
    validateBuildOutput(config.appid)
    console.log(`[构建] 已生成 ${BUILD_OUTPUT_DIR}`)
  } finally {
    writeFileSync(MANIFEST_PATH, originalManifest, 'utf8')
  }
}

void main().catch((error: unknown) => {
  const message = error instanceof Error ? error.message : String(error)
  console.error(`\n[失败] ${message}`)
  process.exitCode = 1
})