/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.googlesource.gerrit.plugins.support

import java.io.{File, FileNotFoundException}

import com.google.gerrit.extensions.annotations.{PluginName => GerritPlugiName}
import com.google.gerrit.server.CurrentUser
import com.google.inject.{Inject, Provider, Singleton}
import com.googlesource.gerrit.plugins.support.GerritFacade._
import com.googlesource.gerrit.plugins.support.latest.CollectServerDataCapability._
import eu.medsea.mimeutil.detector.ExtensionMimeDetector
import org.scalatra._
import org.scalatra.util.Mimes

import scala.collection.JavaConversions._
import scala.util.{Failure, Success}
import org.slf4j.LoggerFactory

@Singleton
class GerritSupportServlet @Inject()(val processor: RequestProcessor,
                                     bundleFactory: SupportBundleFile,
                                     mimeDetector: ExtensionMimeDetector,
                                     currentUserProvider: Provider[CurrentUser],
                                     @GerritPlugiName gerritPluginName: String)
  extends ScalatraServlet with Mimes {
  val log = LoggerFactory.getLogger(classOf[GerritSupportServlet])

  implicit val pluginName = new PluginName(gerritPluginName)

  post("/")(requireAdministrateServerPermissions {
    processor.processRequest(request.body) match {
      case Success(zipped) =>
        Created("OK", Map(
          "Location" -> s"${request.getRequestURI}/${zipped.getName}"))
      case Failure(e) => {
        log.error(s"Error serving POST ${request.getRequestURI}", e)
        InternalServerError(reason = e.getLocalizedMessage)
      }
    }
  })

  get("/:filename")(requireAdministrateServerPermissions {
    val bundleFilename = params.getOrElse("filename", halt(BadRequest("Missing or invalid bundle name")))

    bundleFactory(bundleFilename) match {
      case Success(bundleFile: File) =>
        Ok(bundleFile, Map("Content-Type" -> mimeType(bundleFilename)))

      case Failure(e: FileNotFoundException) => NotFound("Bundle not found")

      case Failure(e: IllegalArgumentException) => BadRequest("Invalid bundle name")

      case Failure(t: Throwable) => {
        log.error(s"Error serving GET ${request.getRequestURI}", t)
        InternalServerError(reason = t.getLocalizedMessage)
      }
    }
  })

  private def requireAdministrateServerPermissions(block: => ActionResult) = {
    val currentUser = currentUserProvider.get
    currentUser match {
      case user if user.isIdentifiedUser && user.getCapabilities.canDo(COLLECT_SERVER_DATA).getOrElse(false) => block
      case _ => Forbidden("NOT ALLOWED to collect server data")
    }
  }

  private def mimeType(filename: String) = mimeDetector.getMimeTypes(filename)
    .map(_.toString)
    .headOption.getOrElse("application/octect-stream")
}