package org.broadinstitute.sting.queue.engine

import java.io.File
import org.broadinstitute.sting.queue.function.CommandLineFunction
import org.broadinstitute.sting.queue.util._
import org.broadinstitute.sting.queue.QException
import org.broadinstitute.sting.jna.lsf.v7_0_6.{LibLsf, LibBat}
import org.broadinstitute.sting.jna.lsf.v7_0_6.LibBat.{signalBulkJobs, submitReply, submit}
import org.broadinstitute.sting.utils.Utils
import com.sun.jna.{NativeLong, Memory}
import org.broadinstitute.sting.jna.clibrary.LibC
import java.util.Date

/**
 * Runs jobs on an LSF compute cluster.
 */
class Lsf706JobRunner(val function: CommandLineFunction) extends CommandLineJobRunner with Logging {

  // Run the static initializer for Lsf706JobRunner
  Lsf706JobRunner

  /** Job Id of the currently executing job. */
  var jobId = -1L

  /** Last known run status */
  private var runStatus: RunnerStatus.Value = _

  /**
   * Dispatches the function on the LSF cluster.
   * @param function Command to run.
   */
  def start() = {
    val request = new submit
    for (i <- 0 until LibLsf.LSF_RLIM_NLIMITS)
        request.rLimits(i) = LibLsf.DEFAULT_RLIMIT;

    request.outFile = function.jobOutputFile.getPath
    request.options |= LibBat.SUB_OUT_FILE

    if (function.jobErrorFile != null) {
      request.errFile = function.jobErrorFile.getPath
      request.options |= LibBat.SUB_ERR_FILE
    }

    if (function.jobProject != null) {
      request.projectName = function.jobProject
      request.options |= LibBat.SUB_PROJECT_NAME
    }

    if (function.jobQueue != null) {
      request.queue = function.jobQueue
      request.options |= LibBat.SUB_QUEUE
    }

    if (IOUtils.absolute(new File(".")) != function.commandDirectory) {
      request.cwd = function.commandDirectory.getPath
      request.options3 |= LibBat.SUB3_CWD
    }

    if (function.jobRestartable) {
      request.options |= LibBat.SUB_RERUNNABLE
    }

    if (function.memoryLimit.isDefined) {
      request.resReq = "rusage[mem=" + function.memoryLimit.get + "]"
      request.options |= LibBat.SUB_RES_REQ
    }

    if (function.description != null) {
      request.jobName = function.description.take(1000)
      request.options |= LibBat.SUB_JOB_NAME
    }

    if (function.jobLimitSeconds.isDefined) {
      request.rLimits(LibLsf.LSF_RLIMIT_RUN) = function.jobLimitSeconds.get
    }

    writeExec()
    request.command = "sh " + exec

    // Allow advanced users to update the request.
    updateJobRun(request)

    runStatus = RunnerStatus.RUNNING
    Retry.attempt(() => {
      val reply = new submitReply
      jobId = LibBat.lsb_submit(request, reply)
      if (jobId < 0)
        throw new QException(LibBat.lsb_sperror("Unable to submit job"))
    }, 1, 5, 10)
    logger.info("Submitted LSF job id: " + jobId)
  }

  /**
   * Updates and returns the status.
   */
  def status = {
    var jobStatus = LibBat.JOB_STAT_NULL
    var exitStatus = 0
    var exitInfo = 0
    var endTime: NativeLong = null

    LibBat.lsb_openjobinfo(jobId, null, null, null, null, LibBat.ALL_JOB)
    try {
      val jobInfo = LibBat.lsb_readjobinfo(null)
      if (jobInfo == null) {
        jobStatus = LibBat.JOB_STAT_UNKWN
        exitStatus = 0
        exitInfo = 0
        endTime = null
      } else {
        jobStatus = jobInfo.status
        exitStatus = jobInfo.exitStatus
        exitInfo = jobInfo.exitInfo
        endTime = jobInfo.endTime
      }
    } finally {
      LibBat.lsb_closejobinfo()
    }

    logger.debug("Job Id %s status / exitStatus / exitInfo: 0x%02x / 0x%02x / 0x%02x".format(jobId, jobStatus, exitStatus, exitInfo))

    if (Utils.isFlagSet(jobStatus, LibBat.JOB_STAT_UNKWN)) {
      val now = new Date().getTime

      if (firstUnknownTime.isEmpty) {
        firstUnknownTime = Some(now)
        logger.debug("First unknown status for job id: " + jobId)
      }

      if ((firstUnknownTime.get - now) >= (unknownStatusMaxSeconds * 1000L)) {
        // Unknown status has been returned for a while now.
        runStatus = RunnerStatus.FAILED
        logger.error("Unknown status for %d seconds: job id %d: %s".format(unknownStatusMaxSeconds, jobId, function.description))
      }
    } else {
      // Reset the last time an unknown status was seen.
      firstUnknownTime = None

      if (Utils.isFlagSet(jobStatus, LibBat.JOB_STAT_EXIT) && !willRetry(exitInfo, endTime)) {
        // Exited function that (probably) won't be retried.
        runStatus = RunnerStatus.FAILED
      } else if (Utils.isFlagSet(jobStatus, LibBat.JOB_STAT_DONE)) {
        // Done successfully.
        runStatus = RunnerStatus.DONE
      }
    }

    runStatus
  }

  /**
   * Returns true if LSF is expected to retry running the function.
   * @param exitInfo The reason the job exited.
   * @param endTime THe time the job exited.
   * @return true if LSF is expected to retry running the function.
   */
  private def willRetry(exitInfo: Int, endTime: NativeLong) = {
    exitInfo match {
      case LibBat.EXIT_NORMAL => false
      case _ => {
        val seconds = LibC.difftime(LibC.time(null), endTime)
        (seconds <= retryExpiredSeconds)
      }
    }
  }

}

object Lsf706JobRunner extends Logging {
  init()

  /**
   * Initialize the Lsf library.
   */
  private def init() = {
    if (LibBat.lsb_init("Queue") < 0)
      throw new QException(LibBat.lsb_sperror("lsb_init() failed"))
  }

  /**
   * Tries to stop any running jobs.
   * @param runners Runners to stop.
   */
  def tryStop(runners: List[Lsf706JobRunner]) {
    for (jobRunners <- runners.filterNot(_.jobId < 0).grouped(10)) {
      try {
        val njobs = jobRunners.size
        val signalJobs = new signalBulkJobs
        signalJobs.jobs = {
          val jobIds = new Memory(8 * njobs)
          jobIds.write(0, jobRunners.map(_.jobId).toArray, 0, njobs)
          jobIds
        }
        signalJobs.njobs = njobs
        signalJobs.signal = 9

        if (LibBat.lsb_killbulkjobs(signalJobs) < 0)
          throw new QException(LibBat.lsb_sperror("lsb_killbulkjobs failed"))
      } catch {
        case e =>
          logger.error("Unable to kill all jobs.", e)
      }
    }
  }
}