sbt/plugin/src/main/scala/coursier/CoursierPlugin.scala

package coursier

import java.io.{ File, OutputStreamWriter }

import coursier.cli.TermDisplay
import coursier.ivy.IvyRepository
import sbt.{ MavenRepository => _, _ }
import sbt.Keys._

import scalaz.{ -\/, \/- }
import scalaz.concurrent.Task

object CoursierPlugin extends AutoPlugin {

  private def grouped[K, V](map: Seq[(K, V)]): Map[K, Seq[V]] =
    map.groupBy { case (k, _) => k }.map {
      case (k, l) =>
        k -> l.map { case (_, v) => v }
    }

  override def trigger = allRequirements

  override def requires = sbt.plugins.IvyPlugin

  private def errPrintln(s: String): Unit = scala.Console.err.println(s)

  object autoImport {
    val coursierParallelDownloads = Keys.coursierParallelDownloads
    val coursierMaxIterations = Keys.coursierMaxIterations
    val coursierChecksums = Keys.coursierChecksums
    val coursierCachePolicy = Keys.coursierCachePolicy
    val coursierVerbosity = Keys.coursierVerbosity
    val coursierResolvers = Keys.coursierResolvers
    val coursierCache = Keys.coursierCache
    val coursierProject = Keys.coursierProject
    val coursierProjects = Keys.coursierProjects
    val coursierSbtClassifiersModule = Keys.coursierSbtClassifiersModule
  }

  import autoImport._


  private val ivyProperties = Map(
    "ivy.home" -> s"${sys.props("user.home")}/.ivy2"
  ) ++ sys.props

  private def createLogger() = Some {
    new TermDisplay(
      new OutputStreamWriter(System.err),
      fallbackMode = sys.env.get("COURSIER_NO_TERM").nonEmpty
    )
  }


  private def updateTask(withClassifiers: Boolean, sbtClassifiers: Boolean = false) = Def.task {

    // let's update only one module at once, for a better output
    // Downloads are already parallel, no need to parallelize further anyway
    synchronized {

      lazy val cm = coursierSbtClassifiersModule.value

      val currentProject =
        if (sbtClassifiers) {
          FromSbt.project(
            cm.id,
            cm.modules,
            cm.configurations.map(cfg => cfg.name -> cfg.extendsConfigs.map(_.name)).toMap,
            scalaVersion.value,
            scalaBinaryVersion.value
          )
        } else {
          val (p, _) = coursierProject.value
          p
        }

      val projects = coursierProjects.value

      val parallelDownloads = coursierParallelDownloads.value
      val checksums = coursierChecksums.value
      val maxIterations = coursierMaxIterations.value
      val cachePolicy = coursierCachePolicy.value
      val cacheDir = coursierCache.value

      val resolvers = coursierResolvers.value

      val verbosity = coursierVerbosity.value


      val startRes = Resolution(
        currentProject.dependencies.map { case (_, dep) => dep }.toSet,
        filter = Some(dep => !dep.optional),
        forceVersions = projects.map { case (proj, _) => proj.moduleVersion }.toMap
      )

      if (verbosity >= 1) {
        println("InterProjectRepository")
        for ((p, _) <- projects)
          println(s"  ${p.module}:${p.version}")
      }

      val globalPluginsRepo = IvyRepository(
        new File(sys.props("user.home") + "/.sbt/0.13/plugins/target/resolution-cache/").toURI.toString +
        "[organization]/[module](/scala_[scalaVersion])(/sbt_[sbtVersion])/[revision]/resolved.xml.[ext]",
        withChecksums = false,
        withSignatures = false,
        withArtifacts = false
      )

      val interProjectRepo = InterProjectRepository(projects)
      val repositories = Seq(globalPluginsRepo, interProjectRepo) ++ resolvers.flatMap(FromSbt.repository(_, ivyProperties))

      val files = Files(
        Seq("http://" -> new File(cacheDir, "http"), "https://" -> new File(cacheDir, "https")),
        () => ???,
        concurrentDownloadCount = parallelDownloads
      )

      val logger = createLogger()
      logger.foreach(_.init())
      val fetch = coursier.Fetch(
        repositories,
        files.fetch(checksums = checksums, logger = logger)(cachePolicy = CachePolicy.LocalOnly),
        files.fetch(checksums = checksums, logger = logger)(cachePolicy = cachePolicy)
      )

      def depsRepr = currentProject.dependencies.map { case (config, dep) =>
        s"${dep.module}:${dep.version}:$config->${dep.configuration}"
      }.sorted

      if (verbosity >= 0)
        errPrintln(s"Resolving ${currentProject.module.organization}:${currentProject.module.name}:${currentProject.version}")
      if (verbosity >= 1)
        for (depRepr <- depsRepr)
          errPrintln(s"  $depRepr")

      val res = startRes
        .process
        .run(fetch, maxIterations)
        .attemptRun
        .leftMap(ex => throw new Exception(s"Exception during resolution", ex))
        .merge

      if (!res.isDone)
        throw new Exception(s"Maximum number of iteration reached!")

      if (verbosity >= 0)
        errPrintln("Resolution done")

      def repr(dep: Dependency) = {
        // dep.version can be an interval, whereas the one from project can't
        val version = res
          .projectCache
          .get(dep.moduleVersion)
          .map(_._2.version)
          .getOrElse(dep.version)
        val extra =
          if (version == dep.version) ""
          else s" ($version for ${dep.version})"

        (
          Seq(
            dep.module.organization,
            dep.module.name,
            dep.attributes.`type`
          ) ++
          Some(dep.attributes.classifier)
            .filter(_.nonEmpty)
            .toSeq ++
          Seq(
            version
          )
        ).mkString(":") + extra
      }

      if (res.conflicts.nonEmpty) {
        // Needs test
        println(s"${res.conflicts.size} conflict(s):\n  ${res.conflicts.toList.map(repr).sorted.mkString("  \n")}")
      }

      val errors = res.errors

      if (errors.nonEmpty) {
        println(s"\n${errors.size} error(s):")
        for ((dep, errs) <- errors) {
          println(s"  ${dep.module}:${dep.version}:\n${errs.map("    " + _.replace("\n", "    \n")).mkString("\n")}")
        }
      }

      val classifiers =
        if (withClassifiers)
          Some {
            if (sbtClassifiers)
              cm.classifiers
            else
              transitiveClassifiers.value
          }
        else
          None

      val allArtifacts =
        classifiers match {
          case None => res.artifacts
          case Some(cl) => res.classifiersArtifacts(cl)
        }

      val artifactFileOrErrorTasks = allArtifacts.toVector.map { a =>
        files.file(a, checksums = checksums, logger = logger)(cachePolicy = cachePolicy).run.map((a, _))
      }

      if (verbosity >= 0)
        errPrintln(s"Fetching artifacts")

      val artifactFilesOrErrors = Task.gatherUnordered(artifactFileOrErrorTasks).attemptRun match {
        case -\/(ex) =>
          throw new Exception(s"Error while downloading / verifying artifacts", ex)
        case \/-(l) =>
          l.toMap
      }

      if (verbosity >= 0)
        errPrintln(s"Fetching artifacts: done")

      val configs = {
        val configs0 = ivyConfigurations.value.map { config =>
          config.name -> config.extendsConfigs.map(_.name)
        }.toMap

        def allExtends(c: String) = {
          // possibly bad complexity
          def helper(current: Set[String]): Set[String] = {
            val newSet = current ++ current.flatMap(configs0.getOrElse(_, Nil))
            if ((newSet -- current).nonEmpty)
              helper(newSet)
            else
              newSet
          }

          helper(Set(c))
        }

        configs0.map {
          case (config, _) =>
            config -> allExtends(config)
        }
      }

      def artifactFileOpt(artifact: Artifact) = {
        val fileOrError = artifactFilesOrErrors.getOrElse(artifact, -\/("Not downloaded"))

        fileOrError match {
          case \/-(file) =>
            if (file.toString.contains("file:/"))
              throw new Exception(s"Wrong path: $file")
            Some(file)
          case -\/(err) =>
            errPrintln(s"${artifact.url}: $err")
            None
        }
      }

      val depsByConfig = grouped(currentProject.dependencies)

      ToSbt.updateReport(
        depsByConfig,
        res,
        configs,
        classifiers,
        artifactFileOpt
      )
    }
  }

  override lazy val projectSettings = Seq(
    coursierParallelDownloads := 6,
    coursierMaxIterations := 50,
    coursierChecksums := Seq(Some("SHA-1"), None),
    coursierCachePolicy := CachePolicy.FetchMissing,
    coursierVerbosity := 1,
    coursierResolvers <<= Tasks.coursierResolversTask,
    coursierCache := new File(sys.props("user.home") + "/.coursier/sbt"),
    update <<= updateTask(withClassifiers = false),
    updateClassifiers <<= updateTask(withClassifiers = true),
    updateSbtClassifiers in Defaults.TaskGlobal <<= updateTask(withClassifiers = true, sbtClassifiers = true),
    coursierProject <<= Tasks.coursierProjectTask,
    coursierProjects <<= Tasks.coursierProjectsTask,
    coursierSbtClassifiersModule <<= classifiersModule in updateSbtClassifiers
  )

}