const fs = require('fs-extra')
const path = require('path')

const ini = require('ini')
const minimist = require('minimist')
const LRU = require('lru-cache')

const stripAnsi = require('strip-ansi')

const {
  chalk,
  execa,
  semver,
  request,

  resolvePkg,
  loadModule,

  hasYarn,
  hasProjectYarn,
  hasPnpm3OrLater,
  hasPnpmVersionOrLater,
  hasProjectPnpm,
  hasProjectNpm,

  isOfficialPlugin,
  resolvePluginId,

  log,
  warn,
  error
} = require('@vue/cli-shared-utils')

const { loadOptions } = require('../options')
const { executeCommand } = require('./executeCommand')

const registries = require('./registries')
const shouldUseTaobao = require('./shouldUseTaobao')

const metadataCache = new LRU({
  max: 200,
  maxAge: 1000 * 60 * 30 // 30 min.
})

const isTestOrDebug = process.env.VUE_CLI_TEST || process.env.VUE_CLI_DEBUG

const SUPPORTED_PACKAGE_MANAGERS = ['yarn', 'pnpm', 'npm']
const PACKAGE_MANAGER_PNPM4_CONFIG = {
  install: ['install', '--reporter', 'silent', '--shamefully-hoist'],
  add: ['install', '--reporter', 'silent', '--shamefully-hoist'],
  upgrade: ['update', '--reporter', 'silent'],
  remove: ['uninstall', '--reporter', 'silent']
}
const PACKAGE_MANAGER_PNPM3_CONFIG = {
  install: ['install', '--loglevel', 'error', '--shamefully-flatten'],
  add: ['install', '--loglevel', 'error', '--shamefully-flatten'],
  upgrade: ['update', '--loglevel', 'error'],
  remove: ['uninstall', '--loglevel', 'error']
}
const PACKAGE_MANAGER_CONFIG = {
  npm: {
    install: ['install', '--loglevel', 'error'],
    add: ['install', '--loglevel', 'error'],
    upgrade: ['update', '--loglevel', 'error'],
    remove: ['uninstall', '--loglevel', 'error']
  },
  pnpm: hasPnpmVersionOrLater('4.0.0') ? PACKAGE_MANAGER_PNPM4_CONFIG : PACKAGE_MANAGER_PNPM3_CONFIG,
  yarn: {
    install: [],
    add: ['add'],
    upgrade: ['upgrade'],
    remove: ['remove']
  }
}

// extract the package name 'xx' from the format 'xx@1.1'
function stripVersion (packageName) {
  const nameRegExp = /^(@?[^@]+)(@.*)?$/
  const result = packageName.match(nameRegExp)

  if (!result) {
    throw new Error(`Invalid package name ${packageName}`)
  }

  return result[1]
}

class PackageManager {
  constructor ({ context, forcePackageManager } = {}) {
    this.context = context || process.cwd()

    if (forcePackageManager) {
      this.bin = forcePackageManager
    } else if (context) {
      if (hasProjectYarn(context)) {
        this.bin = 'yarn'
      } else if (hasProjectPnpm(context)) {
        this.bin = 'pnpm'
      } else if (hasProjectNpm(context)) {
        this.bin = 'npm'
      }
    }

    // if no package managers specified, and no lockfile exists
    if (!this.bin) {
      this.bin = loadOptions().packageManager || (hasYarn() ? 'yarn' : hasPnpm3OrLater() ? 'pnpm' : 'npm')
    }

    if (this.bin === 'npm') {
      // npm doesn't support package aliases until v6.9
      const MIN_SUPPORTED_NPM_VERSION = '6.9.0'
      const npmVersion = stripAnsi(execa.sync('npm', ['--version']).stdout)

      if (semver.lt(npmVersion, MIN_SUPPORTED_NPM_VERSION)) {
        warn(
          'You are using an outdated version of NPM.\n' +
          'there may be unexpected errors during installation.\n' +
          'Please upgrade your NPM version.'
        )

        this.needsNpmInstallFix = true
      }
    }

    if (!SUPPORTED_PACKAGE_MANAGERS.includes(this.bin)) {
      log()
      warn(
        `The package manager ${chalk.red(this.bin)} is ${chalk.red('not officially supported')}.\n` +
        `It will be treated like ${chalk.cyan('npm')}, but compatibility issues may occur.\n` +
        `See if you can use ${chalk.cyan('--registry')} instead.`
      )
      PACKAGE_MANAGER_CONFIG[this.bin] = PACKAGE_MANAGER_CONFIG.npm
    }

    // Plugin may be located in another location if `resolveFrom` presents.
    const projectPkg = resolvePkg(this.context)
    const resolveFrom = projectPkg && projectPkg.vuePlugins && projectPkg.vuePlugins.resolveFrom

    // Logically, `resolveFrom` and `context` are distinct fields.
    // But in Vue CLI we only care about plugins.
    // So it is fine to let all other operations take place in the `resolveFrom` directory.
    if (resolveFrom) {
      this.context = path.resolve(context, resolveFrom)
    }
  }

  // Any command that implemented registry-related feature should support
  // `-r` / `--registry` option
  async getRegistry () {
    if (this._registry) {
      return this._registry
    }

    const args = minimist(process.argv, {
      alias: {
        r: 'registry'
      }
    })

    if (args.registry) {
      this._registry = args.registry
    } else if (!process.env.VUE_CLI_TEST && await shouldUseTaobao(this.bin)) {
      this._registry = registries.taobao
    } else {
      try {
        this._registry = (await execa(this.bin, ['config', 'get', 'registry'])).stdout
      } catch (e) {
        // Yarn 2 uses `npmRegistryServer` instead of `registry`
        this._registry = (await execa(this.bin, ['config', 'get', 'npmRegistryServer'])).stdout
      }
    }

    this._registry = stripAnsi(this._registry).trim()
    return this._registry
  }

  async getAuthToken () {
    // get npmrc (https://docs.npmjs.com/configuring-npm/npmrc.html#files)
    const possibleRcPaths = [
      path.resolve(this.context, '.npmrc'),
      path.resolve(require('os').homedir(), '.npmrc')
    ]
    if (process.env.PREFIX) {
      possibleRcPaths.push(path.resolve(process.env.PREFIX, '/etc/npmrc'))
    }
    // there's also a '/path/to/npm/npmrc', skipped for simplicity of implementation

    let npmConfig = {}
    for (const loc of possibleRcPaths) {
      if (fs.existsSync(loc)) {
        try {
          // the closer config file (the one with lower index) takes higher precedence
          npmConfig = Object.assign({}, ini.parse(fs.readFileSync(loc, 'utf-8')), npmConfig)
        } catch (e) {
          // in case of file permission issues, etc.
        }
      }
    }

    const registry = await this.getRegistry()
    const registryWithoutProtocol = registry
      .replace(/https?:/, '')     // remove leading protocol
      .replace(/([^/])$/, '$1/')  // ensure ending with slash
    const authTokenKey = `${registryWithoutProtocol}:_authToken`

    return npmConfig[authTokenKey]
  }

  async setRegistryEnvs () {
    const registry = await this.getRegistry()

    process.env.npm_config_registry = registry
    process.env.YARN_NPM_REGISTRY_SERVER = registry

    this.setBinaryMirrors()
  }

  // set mirror urls for users in china
  async setBinaryMirrors () {
    const registry = await this.getRegistry()

    if (registry !== registries.taobao) {
      return
    }

    try {
      // node-sass, chromedriver, etc.
      const binaryMirrorConfig = await this.getMetadata('binary-mirror-config')
      const mirrors = binaryMirrorConfig.mirrors.china
      for (const key in mirrors.ENVS) {
        process.env[key] = mirrors.ENVS[key]
      }

      // Cypress
      const cypressMirror = mirrors.cypress
      const defaultPlatforms = {
        darwin: 'osx64',
        linux: 'linux64',
        win32: 'win64'
      }
      const platforms = cypressMirror.newPlatforms || defaultPlatforms
      const targetPlatform = platforms[require('os').platform()]
      // Do not override user-defined env variable
      // Because we may construct a wrong download url and an escape hatch is necessary
      if (targetPlatform && !process.env.CYPRESS_INSTALL_BINARY) {
        // We only support cypress 3 for the current major version
        const latestCypressVersion = await this.getRemoteVersion('cypress', '^3')
        process.env.CYPRESS_INSTALL_BINARY =
          `${cypressMirror.host}/${latestCypressVersion}/${targetPlatform}/cypress.zip`
      }
    } catch (e) {
      // get binary mirror config failed
    }
  }

  // https://github.com/npm/registry/blob/master/docs/responses/package-metadata.md
  async getMetadata (packageName, { full = false } = {}) {
    const registry = await this.getRegistry()
    const authToken = await this.getAuthToken()

    const metadataKey = `${this.bin}-${registry}-${packageName}`
    let metadata = metadataCache.get(metadataKey)

    if (metadata) {
      return metadata
    }

    const headers = {}
    if (!full) {
      headers.Accept = 'application/vnd.npm.install-v1+json;q=1.0, application/json;q=0.9, */*;q=0.8'
    }

    if (authToken) {
      headers.Authorization = `Bearer ${authToken}`
    }

    const url = `${registry.replace(/\/$/g, '')}/${packageName}`
    try {
      metadata = (await request.get(url, { headers })).body
      if (metadata.error) {
        throw new Error(metadata.error)
      }
      metadataCache.set(metadataKey, metadata)
      return metadata
    } catch (e) {
      error(`Failed to get response from ${url}`)
      throw e
    }
  }

  async getRemoteVersion (packageName, versionRange = 'latest') {
    const metadata = await this.getMetadata(packageName)
    if (Object.keys(metadata['dist-tags']).includes(versionRange)) {
      return metadata['dist-tags'][versionRange]
    }
    const versions = Array.isArray(metadata.versions) ? metadata.versions : Object.keys(metadata.versions)
    return semver.maxSatisfying(versions, versionRange)
  }

  getInstalledVersion (packageName) {
    // for first level deps, read package.json directly is way faster than `npm list`
    try {
      const packageJson = loadModule(`${packageName}/package.json`, this.context, true)
      return packageJson.version
    } catch (e) {}
  }

  async runCommand (command, args) {
    await this.setRegistryEnvs()
    return await executeCommand(
      this.bin,
      [
        ...PACKAGE_MANAGER_CONFIG[this.bin][command],
        ...(args || [])
      ],
      this.context
    )
  }

  async install () {
    if (process.env.VUE_CLI_TEST) {
      try {
        process.env.PUPPETEER_SKIP_CHROMIUM_DOWNLOAD = true
        await this.runCommand('install', ['--offline', '--silent', '--no-progress'])
        delete process.env.PUPPETEER_SKIP_CHROMIUM_DOWNLOAD
      } catch (e) {
        delete process.env.PUPPETEER_SKIP_CHROMIUM_DOWNLOAD
        await this.runCommand('install', ['--silent', '--no-progress'])
      }
    }

    if (this.needsNpmInstallFix) {
      // if npm 5, split into several `npm add` calls
      // see https://github.com/vuejs/vue-cli/issues/5800#issuecomment-675199729
      const pkg = resolvePkg(this.context)
      if (pkg.dependencies) {
        const deps = Object.entries(pkg.dependencies).map(([dep, range]) => `${dep}@${range}`)
        await this.runCommand('install', deps)
      }

      if (pkg.devDependencies) {
        const devDeps = Object.entries(pkg.devDependencies).map(([dep, range]) => `${dep}@${range}`)
        await this.runCommand('install', [...devDeps, '--save-dev'])
      }

      if (pkg.optionalDependencies) {
        const devDeps = Object.entries(pkg.devDependencies).map(([dep, range]) => `${dep}@${range}`)
        await this.runCommand('install', [...devDeps, '--save-optional'])
      }

      return
    }

    return await this.runCommand('install')
  }

  async add (packageName, {
    tilde = false,
    dev = true
  } = {}) {
    const args = dev ? ['-D'] : []
    if (tilde) {
      if (this.bin === 'yarn') {
        args.push('--tilde')
      } else {
        process.env.npm_config_save_prefix = '~'
      }
    }

    return await this.runCommand('add', [packageName, ...args])
  }

  async remove (packageName) {
    return await this.runCommand('remove', [packageName])
  }

  async upgrade (packageName) {
    // manage multiple packages separated by spaces
    const packageNamesArray = []

    for (const packname of packageName.split(' ')) {
      const realname = stripVersion(packname)
      if (
        isTestOrDebug &&
        (packname === '@vue/cli-service' || isOfficialPlugin(resolvePluginId(realname)))
      ) {
        // link packages in current repo for test
        const src = path.resolve(__dirname, `../../../../${realname}`)
        const dest = path.join(this.context, 'node_modules', realname)
        await fs.remove(dest)
        await fs.symlink(src, dest, 'dir')
      } else {
        packageNamesArray.push(packname)
      }
    }

    if (packageNamesArray.length) return await this.runCommand('add', packageNamesArray)
  }
}

module.exports = PackageManager