from django.core.management.base import NoArgsCommand, CommandError
from django.db import transaction
from django.db.models import Q

from bldcontrol.bbcontroller import getBuildEnvironmentController
from bldcontrol.bbcontroller import ShellCmdException, BuildSetupException
from bldcontrol.models import BuildRequest, BuildEnvironment
from bldcontrol.models import BRError, BRVariable

from orm.models import Build, ToasterSetting, LogMessage, Target

import os
import logging
import time
import sys
import traceback

logger = logging.getLogger("toaster")

class Command(NoArgsCommand):
    args    = ""
    help    = "Schedules and executes build requests as possible."
    "Does not return (interrupt with Ctrl-C)"


    @transaction.atomic
    def _selectBuildEnvironment(self):
        bec = getBuildEnvironmentController(lock = BuildEnvironment.LOCK_FREE)
        bec.be.lock = BuildEnvironment.LOCK_LOCK
        bec.be.save()
        return bec

    @transaction.atomic
    def _selectBuildRequest(self):
        br = BuildRequest.objects.filter(state=BuildRequest.REQ_QUEUED).first()
        return br

    def schedule(self):
        try:
            # select the build environment and the request to build
            br = self._selectBuildRequest()
            if br:
                br.state = BuildRequest.REQ_INPROGRESS
                br.save()
            else:
                return

            try:
                bec = self._selectBuildEnvironment()
            except IndexError as e:
                # we could not find a BEC; postpone the BR
                br.state = BuildRequest.REQ_QUEUED
                br.save()
                logger.debug("runbuilds: No build env")
                return

            logger.debug("runbuilds: starting build %s, environment %s" % \
                         (str(br).decode('utf-8'), bec.be))

            # let the build request know where it is being executed
            br.environment = bec.be
            br.save()

            # this triggers an async build
            bec.triggerBuild(br.brbitbake, br.brlayer_set.all(),
                             br.brvariable_set.all(), br.brtarget_set.all(),
                             "%d:%d" % (br.pk, bec.be.pk))

        except Exception as e:
            logger.error("runbuilds: Error launching build %s" % e)
            traceback.print_exc(e)
            if "[Errno 111] Connection refused" in str(e):
                # Connection refused, read toaster_server.out
                errmsg = bec.readServerLogFile()
            else:
                errmsg = str(e)

            BRError.objects.create(req = br,
                    errtype = str(type(e)),
                    errmsg = errmsg,
                    traceback = traceback.format_exc(e))
            br.state = BuildRequest.REQ_FAILED
            br.save()
            bec.be.lock = BuildEnvironment.LOCK_FREE
            bec.be.save()

    def archive(self):
        for br in BuildRequest.objects.filter(state = BuildRequest.REQ_ARCHIVE):
            if br.build == None:
                br.state = BuildRequest.REQ_FAILED
            else:
                br.state = BuildRequest.REQ_COMPLETED
            br.save()

    def cleanup(self):
        from django.utils import timezone
        from datetime import timedelta
        # environments locked for more than 30 seconds
        # they should be unlocked
        BuildEnvironment.objects.filter(
            Q(buildrequest__state__in=[BuildRequest.REQ_FAILED,
                                       BuildRequest.REQ_COMPLETED,
                                       BuildRequest.REQ_CANCELLING]) &
            Q(lock=BuildEnvironment.LOCK_LOCK) &
            Q(updated__lt=timezone.now() - timedelta(seconds = 30))
        ).update(lock=BuildEnvironment.LOCK_FREE)


        # update all Builds that were in progress and failed to start
        for br in BuildRequest.objects.filter(
            state=BuildRequest.REQ_FAILED,
            build__outcome=Build.IN_PROGRESS):
            # transpose the launch errors in ToasterExceptions
            br.build.outcome = Build.FAILED
            for brerror in br.brerror_set.all():
                logger.debug("Saving error %s" % brerror)
                LogMessage.objects.create(build=br.build,
                                          level=LogMessage.EXCEPTION,
                                          message=brerror.errmsg)
            br.build.save()

            # we don't have a true build object here; hence, toasterui
            # didn't have a change to release the BE lock
            br.environment.lock = BuildEnvironment.LOCK_FREE
            br.environment.save()


        # update all BuildRequests without a build created
        for br in BuildRequest.objects.filter(build = None):
            br.build = Build.objects.create(project=br.project,
                                            completed_on=br.updated,
                                            started_on=br.created)
            br.build.outcome = Build.FAILED
            try:
                br.build.machine = br.brvariable_set.get(name='MACHINE').value
            except BRVariable.DoesNotExist:
                pass
            br.save()
            # transpose target information
            for brtarget in br.brtarget_set.all():
                Target.objects.create(build=br.build,
                                      target=brtarget.target,
                                      task=brtarget.task)
            # transpose the launch errors in ToasterExceptions
            for brerror in br.brerror_set.all():
                LogMessage.objects.create(build=br.build,
                                          level=LogMessage.EXCEPTION,
                                          message=brerror.errmsg)

            br.build.save()

        # Make sure the LOCK is removed for builds which have been fully
        # cancelled
        for br in BuildRequest.objects.filter(
            Q(build__outcome=Build.CANCELLED) &
            Q(state=BuildRequest.REQ_CANCELLING) &
            ~Q(environment=None)):
            br.environment.lock = BuildEnvironment.LOCK_FREE
            br.environment.save()


    def handle_noargs(self, **options):
        while True:
            try:
                self.cleanup()
            except Exception as e:
                logger.warn("runbuilds: cleanup exception %s" % str(e))

            try:
                self.archive()
            except Exception as e:
                logger.warn("runbuilds: archive exception %s" % str(e))

            try:
                self.schedule()
            except Exception as e:
                logger.warn("runbuilds: schedule exception %s" % str(e))

            time.sleep(1)