import * as tc from '@actions/tool-cache'
import * as core from '@actions/core'
import * as httpm from '@actions/http-client'
import { GitHubRelease } from './github-release'

/**
 * Download a specific version of the Clang.
 * @param version The version to download
 * @returns {Promise<string>} Returns the path of the downloaded clang binary
 */
export async function download(version: string): Promise<string> {
  const findCachedPath = tc.find('clang', version)

  if (findCachedPath !== '') {
    core.info(
      `Using cached Clang ${version} (${process.platform}, ${process.arch})`
    )
    return findCachedPath
  }

  let path

  switch (process.platform) {
    case 'win32':
      path = `clang+llvm-${version}-x86_64-pc-windows-msvc.tar.xz`
      break
    default:
      path = `clang+llvm-${version}-x86_64-linux-gnu-ubuntu-18.04.tar.xz`
      break
  }

  const url = `https://github.com/llvm/llvm-project/releases/download/llvmorg-${version}/${path}`

  core.info(
    `Downloading Clang ${version} (${process.platform}, ${process.arch}) from ${url} ...`
  )

  const archivePath = await tc.downloadTool(url)

  core.info(`Extracting Clang archive...`)

  const extractedPath = await tc.extractTar(archivePath, undefined, 'xf')
  const cachedPath = await tc.cacheDir(extractedPath, 'clang', version)

  return cachedPath
}

export async function getLatestVersion(): Promise<string> {
  const http = new httpm.HttpClient('siteorg/setup-clang')
  const url = 'https://api.github.com/repos/llvm/llvm-project/releases'

  const response = await http.getJson<GitHubRelease[]>(url)

  if (!(response.statusCode == 200)) {
    throw new Error(
      `GitHub API request failed with status ${response.statusCode}`
    )
  }

  const releaseData = response.result

  if (releaseData == null) {
    throw new Error('No releases found.')
  }

  const stableReleases = releaseData.filter(release => !release.prerelease)

  if (stableReleases.length === 0) {
    throw new Error('No stable releases found.')
  }

  const latestStableRelease = stableReleases[0]
  const latestReleaseTag = latestStableRelease.tag_name

  return latestReleaseTag.replace('llvmorg-', '')
}