from django.db import models
from django.urls import reverse
from django.utils import timezone
from django.utils.timezone import datetime, timedelta
from django.conf import settings
import json
import logging

from .services import calculated_qualities as qualities
from .services.common import State

logger = logging.getLogger(__name__)

# constants
datetime_format_string = '%Y-%m-%dT%H:%M:%SZ'


class Workflow(models.Model):
    description = models.CharField(max_length=500, blank=True, null=True)
    tag = models.CharField(max_length=30, blank=True, null=True)
    workflow_uri = models.CharField(unique=True, max_length=30, blank=True, null=True)
    repository = models.CharField(max_length=100, blank=True, null=True)
    commit_id = models.CharField(max_length=100, blank=True, null=True)
    path = models.CharField(max_length=100, blank=True, null=True)
    oi_size_fraction = models.FloatField(blank=True, null=True)
    meta_scheduling = models.JSONField(null=True, blank=True)
    default_parameters = models.JSONField(null=True, blank=True)
    prefetch = models.BooleanField(null=True, default=True)

    def __str__(self):
        return str(self.id) + ' - ' + str(self.workflow_uri)


# convert the quality information from the JSONfield into a easy parsable list for the template
def convert_quality_to_list_for_template(task):
    list = []

    try:
        list.append(str(task.quality_json['uv-coverage']))
    except:
        list.append("-")

    try:
        list.append(str(task.quality_json['sensitivity']))
    except:
        list.append("-")

    try:
        list.append(str(task.quality_json['observing-conditions']))
    except:
        list.append("-")

    return list


def convert_quality_to_shortlist_for_template(task):
    list = []

    try:
        list.append(str(task.quality_json['uv-coverage']))
        list.append(str(task.quality_json['sensitivity']))
        list.append(str(task.quality_json['observing-conditions']))
    except Exception as err:
        pass

    return list

def convert_summary_to_list_for_template(task):
    list = []

    try:
        summary = task.quality_json['summary']

    except Exception as err:
        pass

    return list

def associate_task_with_activity(task):

    if not task.activity:

        try:
            activity = Activity.objects.get(sas_id=task.sas_id)
        except:
            # no activity exists yet, create it
            logger.info(f'create new activity for sas_id {task.sas_id}')

            activity = Activity(sas_id=task.sas_id,
                                project=task.project,
                                filter=task.filter)
            activity.save()

        task.activity = activity

    return task.activity

class Activity(models.Model):
    """
    Aggregation per SAS_ID level
    """

    sas_id = models.CharField(db_index=True, verbose_name="SAS_ID", max_length=15, blank=True, null=True)
    workflow_id = models.IntegerField(null=True)
    project = models.CharField(max_length=100, blank=True, null=True, default="unknown")
    filter = models.CharField(max_length=30, blank=True, null=True)

    status = models.CharField(db_index=True, default="unknown", max_length=50, blank=True, null=True)
    calculated_quality = models.CharField(max_length=10, blank=True, null=True)

    # this is the JSON blob that is filled in by the ldv_archiver during the ingest process
    archive = models.JSONField(null=True, blank=True)

    # set by update_activity, used by Validation Page
    is_verified  = models.BooleanField(default=False)

    # TODO: flag set by the 'validate' step in ATDB, used by combine service
    is_validated = models.BooleanField(default=False)

    # TODO: flag set (and used) by the combine service, so that it doesn't do double work
    is_combined = models.BooleanField(default=False)

    finished_fraction = models.FloatField(blank=True, null=True)
    ingested_fraction = models.FloatField(blank=True, null=True)
    total_size = models.FloatField(blank=True, null=True)
    remaining = models.FloatField(blank=True, null=True)

    ingestq_status = models.JSONField(null=True, blank=True)

    @property
    def has_archived(self):
        """
        check if any task belonging to this sas_id already has an output SAS_ID at the LTA
        """
        try:
            if self.archive['sas_id_archived']:
                return self.archive['sas_id_archived']

        except:
            return None

    def __str__(self):
        return str(self.sas_id)


def check_if_summary(task):
    """
    check if this task is a summary task
    for backward compatiblity reasons this is done very ugly, by looking if certain filenames contain the substring 'summary'
    """
    # look in the outputs.tar_archive
    try:
        tars = task.outputs['tar_archive']
        for tar in tars:
            if 'summary' in tar['basename']:
                # a summary tarball was found, this task is a summary task
                return True
    except:
        # no 'tar_archive' was found
        return False

    return False

class Task(models.Model):

    # Task control properties
    task_type = models.CharField(max_length=20, default="regular")
    is_summary = models.BooleanField(default=False)
    filter = models.CharField(max_length=30, blank=True, null=True)
    environment = models.CharField(max_length=255, blank=True, null=True)
    new_status = models.CharField(max_length=50, default="defining", null=True)
    status = models.CharField(db_index=True, default="unknown", max_length=50,blank=True, null=True)
    quality = models.CharField(max_length=10,blank=True, null=True)
    calculated_qualities = models.JSONField(null=True, blank=True)
    resume = models.BooleanField(verbose_name="Resume", default=True)
    creationTime = models.DateTimeField(verbose_name="CreationTime",default=timezone.now, blank=True)

    priority = models.IntegerField(default=100, null=True)
    purge_policy = models.CharField(max_length=5, default="no", blank=True, null=True)
    cleanup_policy = models.CharField(max_length=30, blank=True, null=True)
    stage_request_id = models.IntegerField(null=True)

    # LOFAR properties
    project = models.CharField(max_length=100, blank=True, null=True, default="unknown")
    sas_id = models.CharField(verbose_name="SAS_ID",max_length=15, blank=True, null=True)
    inputs = models.JSONField(null=True, blank=True)
    outputs = models.JSONField(null=True, blank=True)
    metrics = models.JSONField(null=True, blank=True)
    remarks = models.JSONField(null=True, blank=True)
    meta_scheduling = models.JSONField(null=True, blank=True)
    archive = models.JSONField(null=True, blank=True)

    size_to_process = models.PositiveBigIntegerField(default=0, null=True, blank=True)
    size_processed = models.PositiveBigIntegerField(default=0, null=True, blank=True)
    total_processing_time = models.IntegerField(default=0, null=True, blank=True)

    # relationships
    workflow = models.ForeignKey(Workflow, related_name='tasks', on_delete=models.CASCADE, null=True, blank=True)
    predecessor = models.ForeignKey('self', related_name='successors', on_delete=models.SET_NULL, null=True, blank=True)
    joined_output_task = models.ForeignKey('self', related_name='joined_input_tasks', on_delete=models.SET_NULL, null=True, blank=True)

    # pipeline or observation
    activity = models.ForeignKey(Activity, related_name='tasks', on_delete=models.SET_NULL, null=True, blank=True)

    def __str__(self):
        return str(self.id) + ' - (' + self.task_type + ') - ' + str(self.sas_id)

    def save(self, *args, **kwargs):
        # nv:1mar2023, temporary hack, set tasks 'on hold' as soon they get to 'scrubbed'
        # (users forget to do that manually, causing unwanted ingests)
        if (self.status != State.SCRUBBED.value) & (self.new_status == State.SCRUBBED.value):
            self.resume = False

        # nv:19jun2023, calculate the qualities for this task
        if (self.status != State.STORED.value) & (self.new_status == State.STORED.value):

            # read the quality_thresholds from the Configuration table
            try:
                quality_thresholds = json.loads(Configuration.objects.get(key='quality_thresholds').value)
            except:
                quality_thresholds = {
                    "moderate": 20,
                    "poor": 50,
                    "overall_poor": 50,
                    "overall_good": 90,
                }

            tasks_for_this_sasid = Task.objects.filter(sas_id=self.sas_id)
            self.calculated_qualities = qualities.calculate_qualities(self, tasks_for_this_sasid, quality_thresholds)

        # nv:20feb2024, check if this task is a summary task
        if (self.status != State.STORED.value) & (self.new_status == State.STORED.value):
            self.is_summary = check_if_summary(self)

        # nv:20feb2024, same as above, but for backward compatibilty reasons.
        # For tasks that are already beyond PROCESSED, but not yet ingested.
        if (self.status != State.VALIDATED.value) & (self.new_status == State.VALIDATED.value):
            self.is_summary = check_if_summary(self)

        # make sure that every task has an activity (also for backward compatibility)
        associate_task_with_activity(self)

        # remark:
        # a post_save signal is triggered by this save()
        # to update the associated 'activity' with relevant aggregated information

        super(Task, self).save(*args, **kwargs)


    # this translates a view-name (from urls.py) back to a url, to avoid hardcoded url's in the html templates
    # bad : <td><a href="/atdb/tasks/{{ task.id }}/" target="_blank">{{ task.taskID }} </a> </td>
    # good: <td><a href="{{ task.get_absolute_url }}" target="_blank">{{ task.taskID }} </a> </td>
    def get_absolute_url(self):
        return reverse('task-detail-view-api', kwargs={'pk': self.pk})

    def get_jobs_statusses(self):
        statusses = {}

        # check the statusses of all the jobs of this id
        jobs = Job.objects.filter(task_id=self.id)
        for job in jobs:

            try:
                key = job.metadata['status'].lower()
                # if key doesn't exist, add a new one
                try:
                    statusses[key] = statusses[key] + 1
                except:
                    statusses.update({ key : 0 })
                    statusses[key] = statusses[key] + 1

            except:
                pass

        return statusses


    @property
    def predecessor_status(self):
        try:
            return self.predecessor.status
        except:
            return "no_predecessor"

    @property
    def has_quality(self):
        try:
            quality = self.outputs['quality']
            return True
        except:
            return False

    @property
    def has_plots(self):
        try:
            quality = self.outputs['quality']
            plots = quality['plots']
            if len(plots) > 0:
                return True
            else:
                return False

        except:
            return False

    @property
    def has_summary(self):
        try:
            summary = self.outputs['quality']['summary']
            return True
        except:
            return False


    @property
    def quality_json(self):
        try:
            return self.outputs['quality']
        except:
            return None

    @property
    def get_quality_remarks(self):
        try:
            return self.remarks['quality']
        except:
            return None

    @property
    def get_quality_remarks_taskid(self):
        try:
            return self.remarks['quality_taskid']
        except:
            return None

    @property
    def get_quality_remarks_sasid(self):
        try:
            return self.remarks['quality_sasid']
        except:
            return None

    @property
    def quality_as_list(self):
        try:
            q = convert_quality_to_list_for_template(self)
            return q
        except:
            return None

    @property
    def quality_as_shortlist(self):
        try:
            q = convert_quality_to_shortlist_for_template(self)
            return q
        except:
            return None

    @property
    def summary_as_list(self):
        try:
            q = convert_summary_to_list_for_template(self)
            return q
        except:
            return None

    @property
    def sas_id_archived(self):
        """
        check if this task already has an output SAS_ID at the LTA
        """
        try:
            return self.archive['sas_id_archived']
        except:
            return None

    @property
    def path_to_lta(self):
        """
        return the 'path_to_lta' of this task (or None if that fails)
        """
        try:
            return self.archive['path_to_lta']
        except:
            return None

    @property
    def task_type_join(self):
        try:
            # find out if this is a join/joined type of task, or just a regular task
            if self.joined_output_task:
                # this tasks has a designated output task, so it is an input task (join)
                return 'join'

            joined_input_tasks = self.joined_input_tasks.all()
            if joined_input_tasks.count()>0:
                # this task has input tasks, so it is an output task (joined)
                return 'joined'

            return 'regular'
        except:
            # 'the show must go on', don't crash if anything goes wrong, just show it as 'regular'
            return 'regular'

    @property
    def joined_status(self):
        # if a task has joined_input_tasks, then check their status
        try:
            joined_input_tasks = self.joined_input_tasks.all()
            status = None
            for task in joined_input_tasks:
                if status and task.status != status:
                    return None
                status = task.status

            # all statusses are the same, return it
            return status
        except Exception as e:
            print(e)

        return "unknown"

    @property
    def stageit_url(self):
        stage_request_id = self.stage_request_id
        if stage_request_id:
            stager_api = Configuration.objects.get(key='stager:api').value
            url = f"{stager_api}/requests/{self.stage_request_id}/"
            return url
        else:
            return None

    # NV: this shows the latest status change, but because it is a derived property it cannot be sorted.
    # This functionality was not requested, and to avoid additional requests about 'sort' functionalty
    # it is currently commented out. Could be of use later though, so I leave it in for now.
    # @property
    # def latest_change(self):
    #     qs = Status.objects.filter(task__id=self.id).order_by('-timestamp')
    #     if len(qs) > 0:
    #         status = qs[0]
    #         timestamp = status.timestamp
    #
    #     return timestamp


class LogEntry(models.Model):
    cpu_cycles = models.IntegerField(null=True,blank=True)
    wall_clock_time = models.IntegerField(null=True,blank=True)
    url_to_log_file = models.CharField(max_length=100, blank=True, null=True)
    service = models.CharField(max_length=30, blank=True, null=True)
    step_name = models.CharField(max_length=30, blank=True, null=True)
    timestamp = models.DateTimeField(blank=True, null=True)
    status = models.CharField(max_length=50,default="defined", blank=True, null=True)
    description = models.CharField(max_length=255, blank=True, null=True)
    size_processed = models.PositiveBigIntegerField(default=0, null=True, blank=True)
    # relationships
    task = models.ForeignKey(Task, related_name='log_entries', on_delete=models.CASCADE, null=False)

    def __str__(self):
        return str(self.id)+ ' - '+ str(self.task)+' - '+self.status +' ('+self.step_name+')'

    def save(self, *args, **kwargs):
        #override save to check how long this task has been in this state.
        try:

            # if this logentry already has a wall_clock_time, then don't change it.
            if not self.wall_clock_time:

                # gather all entries for this task, to discover the previous one.
                entries_for_this_task = LogEntry.objects.filter(task=self.task).order_by("-timestamp")
                # remove entries from the list, including 'this', so that the latest remaining is the previous entry.
                for entry in entries_for_this_task:
                    entries_for_this_task = entries_for_this_task.exclude(id=entry.id)
                    if entry == self:
                        break

                try:
                    latest_entry_before_self = entries_for_this_task.latest('timestamp')
                    previous_timestamp = latest_entry_before_self.timestamp
                except:
                    # if no previous entry exists, then use the timestamp from the task.
                    previous_timestamp = self.task.creationTime

                dt = (self.timestamp - previous_timestamp).seconds
                #message = "logentry for task "+str(self.task.id)+", to "+self.status + " took " + str(dt) + " seconds"
                #logger.info(message)

                self.wall_clock_time = dt
        except Exception as e:
            print(e)

        finally:
            # finally save the Monitor info itself also
            super(LogEntry, self).save(*args, **kwargs)



class Status(models.Model):
    name = models.CharField(max_length=50, default="unknown")
    timestamp = models.DateTimeField(default=timezone.now, blank=True)

    # relationships
    task = models.ForeignKey(Task, related_name='status_history', on_delete=models.CASCADE, null=False)

    # the representation of the value in the REST API
    def __str__(self):
        formatedDate = self.timestamp.strftime(datetime_format_string)
        return str(self.name)+' ('+str(formatedDate)+')'


class Configuration(models.Model):
    filter = models.CharField(max_length=30, blank=True, null=True)
    key = models.CharField(max_length=50)
    # large value needed to hold the dcache token
    value = models.CharField(max_length=5120)

    # the representation of the value in the REST API
    def __str__(self):
        return str(self.key)


class Job(models.Model):
    type = models.CharField(db_index=True, max_length=20, default=None,null=True, blank=True)
    task_id = models.IntegerField(null=True, blank=True)
    job_id = models.IntegerField(null=True, blank=True)
    timestamp = models.DateTimeField(default=timezone.now, blank=True)
    metadata = models.JSONField(null=True, blank=True)

    # the representation of the value in the REST API
    def __str__(self):
        return 'task_id:'+str(self.task_id)+', job_id:'+str(self.job_id)

    @property
    def webdav_url(self):
        try:
            path = self.metadata['stdout_path']

            # form the webdav url
            s = path.rsplit('/', 1)
            l = s[0].split('/run')
            webdav_url = "https://public.spider.surfsara.nl/project/ldv/run" + l[1]

            return webdav_url
        except:
            return "N/A"


class PostProcessingRule(models.Model):
    aggregation_key = models.CharField(db_index=True, max_length=20, default=None,null=True, blank=True)
    trigger_status = models.CharField(db_index=True, default="unknown", max_length=50, blank=True, null=True)

    # relationships
    workflow_to_process = models.ForeignKey(Workflow, related_name='to_process', on_delete=models.SET_NULL, null=True, blank=True)
    workflow_to_apply = models.ForeignKey(Workflow, related_name='to_apply',on_delete=models.SET_NULL, null=True, blank=True)

    # the representation of the value in the REST API
    def __str__(self):
        return str(self.aggregation_key)+' - '+str(self.trigger_status)


class LatestMonitor(models.Model):
    name = models.CharField(max_length=50, default="unknown")
    type = models.CharField(max_length=20, default="ldv-service", null=True, blank=True)
    timestamp = models.DateTimeField(default=datetime.utcnow, blank=True)
    hostname = models.CharField(max_length=50, default="unknown")
    process_id = models.IntegerField(null=True, blank=True)
    description = models.CharField(max_length=255, blank=True, null=True)
    status = models.CharField(max_length=50, default="ok", null=True)
    metadata = models.JSONField(null=True, blank=True)

    @property
    def enabled(self):
        try:
            enabled = self.metadata['enabled']
            return enabled
        except:
            # only when metadata['enabled']=False' this will be register as false.
            # to make sure that services are enabled by default
            return "True"

    # the representation of the value in the REST API
    def __str__(self):
        return str(self.name) + ' - ('+ self.hostname+') - '+str(self.timestamp) + ' - ' + self.status


def purge_old_records():
    current_time = timezone.now()  # change this
    try:
        time_threshold = current_time - timedelta(hours=settings.MAX_MONITORING_HISTORY_HOURS)
        records_to_delete = Monitor.objects.filter(timestamp__lt=time_threshold).delete()
    except Exception as e:
        # if MAX_MONITORING_HISTORY_HOURS is not set, then do nothing and continue
        pass


class Monitor(models.Model):
    name = models.CharField(max_length=50, default="unknown")
    type = models.CharField(max_length=20, default="ldv-service", null=True, blank=True)
    timestamp = models.DateTimeField(default=datetime.utcnow, blank=True)
    hostname = models.CharField(max_length=50, default="unknown")
    process_id = models.IntegerField(null=True, blank=True)
    description = models.CharField(max_length=255, blank=True, null=True)
    status = models.CharField(max_length=50, default="ok", null=True)
    metadata = models.JSONField(null=True, blank=True)

    def save(self, *args, **kwargs):
        # check if this combination of service name + hostname already exists
        # in the LatestMonitor, and update if it is newer.
        try:
            latestMonitor = LatestMonitor.objects.get(name=self.name,hostname=self.hostname)
            # carry over the metadata, if possible
            latest_metadata = latestMonitor.metadata
            latestMonitor.delete()
        except:
            pass

        # this combination of name and hostname didn't yet exist, create it.
        metadata = self.metadata
        try:
            if latest_metadata:
                metadata = latest_metadata
        except:
            pass

        latestMonitor = LatestMonitor(
            name=self.name,
            type=self.type,
            timestamp=self.timestamp,
            hostname = self.hostname,
            process_id = self.process_id,
            description = self.description,
            status = self.status,
            metadata = metadata
        )
        latestMonitor.save()

        # finally save the Monitor info itself also
        super(Monitor, self).save(*args, **kwargs)

        # and purge the monitoring table to its max
        purge_old_records()

    # the representation of the value in the REST API
    def __str__(self):
        return str(self.name) + ' - ('+ self.hostname+') - '+str(self.timestamp) + ' - ' + self.status