package app

import util.Directory._
import util.Implicits._
import _root_.util.{ReadableRepositoryAuthenticator, JGitUtil, FileTypeUtil, CompressUtil}
import service._
import org.scalatra._
import java.io.File
import org.eclipse.jgit.api.Git
import org.eclipse.jgit.lib._
import org.apache.commons.io.FileUtils
import org.eclipse.jgit.treewalk._

class RepositoryViewerController extends RepositoryViewerControllerBase 
  with RepositoryService with AccountService with ReadableRepositoryAuthenticator

/**
 * The repository viewer.
 */
trait RepositoryViewerControllerBase extends ControllerBase { 
  self: RepositoryService with AccountService with ReadableRepositoryAuthenticator  =>
  
  // TODO separate to AccountController?
  /**
   * Displays user information.
   */
  get("/:owner") {
    val owner = params("owner")
    getAccountByUserName(owner) match {
      case Some(account) => html.user(account, getRepositoriesOfUser(owner, servletContext))
      case None => NotFound()
    }
  }

  /**
   * Returns converted HTML from Markdown for preview.
   */
  post("/:owner/:repository/_preview")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")
    val content    = params("content")
    contentType = "text/html"
    view.helpers.markdown(content, getRepository(owner, repository, servletContext).get, true)
  })

  /**
   * Displays the file list of the repository root and the default branch.
   */
  get("/:owner/:repository")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")

    fileList(owner, repository)
  })
  
  /**
   * Displays the file list of the repository root and the specified branch.
   */
  get("/:owner/:repository/tree/:id")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")
    
    fileList(owner, repository, params("id"))
  })
  
  /**
   * Displays the file list of the specified path and branch.
   */
  get("/:owner/:repository/tree/:id/*")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")
    
    fileList(owner, repository, params("id"), multiParams("splat").head)
  })
  
  /**
   * Displays the commit list of the specified branch.
   */
  get("/:owner/:repository/commits/:branch")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")
    val branchName = params("branch")
    val page       = params.getOrElse("page", "1").toInt
    
    JGitUtil.withGit(getRepositoryDir(owner, repository)){ git =>
      val (logs, hasNext) = JGitUtil.getCommitLog(git, branchName, page, 30)
    
      repo.html.commits(Nil, branchName, getRepository(owner, repository, servletContext).get,
        logs.splitWith{ (commit1, commit2) =>
          view.helpers.date(commit1.time) == view.helpers.date(commit2.time)
        }, page, hasNext)
    }
  })
  
  /**
   * Displays the commit list of the specified resource.
   */
  get("/:owner/:repository/commits/:branch/*")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")
    val branchName = params("branch")
    val path       = multiParams("splat").head //.replaceFirst("^tree/.+?/", "")
    val page       = params.getOrElse("page", "1").toInt
    
    JGitUtil.withGit(getRepositoryDir(owner, repository)){ git =>
      val (logs, hasNext) = JGitUtil.getCommitLog(git, branchName, page, 30, path)
    
      repo.html.commits(path.split("/").toList, branchName, getRepository(owner, repository, servletContext).get,
        logs.splitWith{ (commit1, commit2) =>
          view.helpers.date(commit1.time) == view.helpers.date(commit2.time)
        }, page, hasNext)
    }
  })

  /**
   * Displays the file content of the specified branch or commit.
   */
  get("/:owner/:repository/blob/:id/*")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")
    val id         = params("id") // branch name or commit id
    val raw        = params.get("raw").getOrElse("false").toBoolean
    val path       = multiParams("splat").head //.replaceFirst("^tree/.+?/", "")
    val repositoryInfo = getRepository(owner, repository, servletContext).get

    JGitUtil.withGit(getRepositoryDir(owner, repository)){ git =>
      val revCommit = JGitUtil.getRevCommitFromId(git, git.getRepository.resolve(id))
      
      @scala.annotation.tailrec
      def getPathObjectId(path: String, walk: TreeWalk): ObjectId = walk.next match {
        case true if(walk.getPathString == path) => walk.getObjectId(0)
        case true => getPathObjectId(path, walk)
      }
      
      val treeWalk = new TreeWalk(git.getRepository)
      treeWalk.addTree(revCommit.getTree)
      treeWalk.setRecursive(true)
      val objectId = getPathObjectId(path, treeWalk)
      treeWalk.release
      
      if(raw){
        // Download
        contentType = "application/octet-stream"
        JGitUtil.getContent(git, objectId, false).get
      } else {
        // Viewer
        val large   = FileTypeUtil.isLarge(git.getRepository.getObjectDatabase.open(objectId).getSize)
        val viewer  = if(FileTypeUtil.isImage(path)) "image" else if(large) "large" else "text"
        val content = JGitUtil.ContentInfo(viewer,
            if(viewer == "text") JGitUtil.getContent(git, objectId, false).map(new String(_, "UTF-8")) else None)
        
        repo.html.blob(id, repositoryInfo, path.split("/").toList, content, new JGitUtil.CommitInfo(revCommit))
      }
    }
  })
  
  /**
   * Displays details of the specified commit.
   */
  get("/:owner/:repository/commit/:id")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")
    val id         = params("id")
    
    JGitUtil.withGit(getRepositoryDir(owner, repository)){ git =>
      val revCommit = JGitUtil.getRevCommitFromId(git, git.getRepository.resolve(id))
      repo.html.commit(id, new JGitUtil.CommitInfo(revCommit),
          getRepository(owner, repository, servletContext).get, JGitUtil.getDiffs(git, id))
    }
  })
  
  /**
   * Displays tags.
   */
  get("/:owner/:repository/tags")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")
    
    repo.html.tags(getRepository(owner, repository, servletContext).get)
  })
  
  /**
   * Download repository contents as an archive.
   */
  get("/:owner/:repository/archive/:name")(readableRepository {
    val owner      = params("owner")
    val repository = params("repository")
    val name       = params("name")
    
    if(name.endsWith(".zip")){
      val revision = name.replaceFirst("\\.zip$", "")
      val workDir = getDownloadWorkDir(owner, repository, session.getId)
      if(workDir.exists){
        FileUtils.deleteDirectory(workDir)
      }
      workDir.mkdirs
      
      // clone the repository
      val cloneDir = new File(workDir, revision)
      JGitUtil.withGit(Git.cloneRepository
          .setURI(getRepositoryDir(owner, repository).toURI.toString)
          .setDirectory(cloneDir)
          .call){ git =>
      
        // checkout the specified revision
        git.checkout.setName(revision).call
      }
      
      // remove .git
      FileUtils.deleteDirectory(new File(cloneDir, ".git"))
      
      // create zip file
      val zipFile = new File(workDir, (if(revision.length == 40) revision.substring(0, 10) else revision) + ".zip")
      CompressUtil.zip(zipFile, cloneDir)
      
      contentType = "application/octet-stream"
      zipFile
    } else {
      BadRequest
    }
  })
  
  /**
   * Provides HTML of the file list.
   * 
   * @param owner the repository owner
   * @param repository the repository name
   * @param revstr the branch name or commit id(optional)
   * @param path the directory path (optional)
   * @return HTML of the file list
   */
  private def fileList(owner: String, repository: String, revstr: String = "", path: String = ".") = {
    getRepository(owner, repository, servletContext) match {
      case None => NotFound()
      case Some(repositoryInfo) => {
        val revision = if(revstr.isEmpty){
          repositoryInfo.repository.defaultBranch
        } else {
          revstr
        }

        JGitUtil.withGit(getRepositoryDir(owner, repository)){ git =>
        // get latest commit
          val revCommit = JGitUtil.getRevCommitFromId(git, git.getRepository.resolve(revision))

          val files = JGitUtil.getFileList(git, revision, path)

          // process README.md
          val readme = files.find(_.name == "README.md").map { file =>
            new String(JGitUtil.getContent(Git.open(getRepositoryDir(owner, repository)), file.id, true).get, "UTF-8")
          }

          repo.html.files(
            // current branch
            revision,
            // repository
            repositoryInfo,
            // current path
            if(path == ".") Nil else path.split("/").toList,
            // latest commit
            new JGitUtil.CommitInfo(revCommit),
            // file list
            files,
            // readme
            readme
          )
        }
      }
    }
  }
  
}