import glob
import hashlib
import json
import logging
import os
import threading
import uuid
from datetime import datetime

from sqlalchemy import Column, Integer, String, DateTime, JSON
from sqlalchemy.ext.declarative import declarative_base

from .render_workers.render_worker import RenderStatus, RenderWorkerFactory

logger = logging.getLogger()
Base = declarative_base()


class ScheduledJob(Base):
    __tablename__ = 'scheduled_jobs'
    id = Column(String, primary_key=True)

    # Get file hash on bg thread
    def __get_file_hash(self):
        if os.path.exists(self.worker.input_path):
            self.file_hash = hashlib.md5(open(self.worker.input_path, 'rb').read()).hexdigest()

    def __init__(self, renderer, input_path, output_path, args, priority=2, owner=None, client=None, notify=None,
                 custom_id=None, name=None):
        self.id = custom_id or self.generate_id()

        self.renderer = renderer
        self.input_path = input_path
        self.output_path = output_path
        self.priority = priority
        self.owner = owner
        self.client = client
        self.notify = notify
        self.date_created = datetime.now()
        self.scheduled_start = None
        self.name = name or os.path.basename(input_path) + '_' + self.date_created.strftime("%Y.%m.%d_%H.%M.%S")

        self.worker_object = RenderWorkerFactory.create_worker(renderer, input_path, output_path, args)
        self.worker_object.log_path = self.log_path()
        self.worker_object.validate()

        self.file_hash = None
        threading.Thread(target=self.__get_file_hash).start()  # get file hash on bg thread

    def render_status(self):
        if self.scheduled_start and self.worker.status == RenderStatus.NOT_STARTED:
            return RenderStatus.SCHEDULED
        else:
            return self.worker.status

    def file_hash(self):
        if os.path.exists(self.worker.input_path):
            return hashlib.md5(open(self.worker.input_path, 'rb').read()).hexdigest()
        return None

    def json(self):
        """Converts RenderJob into JSON-friendly dict"""
        job_dict = None
        try:
            job_dict = {
                'id': self.id,
                'name': self.name,
                'input_path': self.input_path,
                'output_path': self.output_path,
                'priority': self.priority,
                'owner': self.owner,
                'client': self.client,
                'notify': self.notify,
                'date_created': self.date_created,
                'scheduled_start': self.scheduled_start,
                'status': self.render_status().value,
                'time_elapsed': self.worker().time_elapsed() if hasattr(self.worker(), 'time_elapsed') else None,
                'file_hash': self.file_hash,
                'percent_complete': self.percent_complete(),
                'file_list': self.file_list(),
                'renderer': self.renderer,
                'worker': self.worker().json() if hasattr(self.worker(), 'json') else {},
            }

            # convert to json and back to auto-convert dates to iso format
            def date_serializer(o):
                if isinstance(o, datetime):
                    return o.isoformat()
            json_convert = json.dumps(job_dict, default=date_serializer)
            job_dict = json.loads(json_convert)
        except Exception as e:
            logger.exception(e)
            logger.error("Error converting to JSON: {}".format(e))
        return job_dict

    def start(self):
        self.worker.start()

    def stop(self):
        self.worker.stop()

    def time_elapsed(self):

        from string import Template

        class DeltaTemplate(Template):
            delimiter = "%"

        def strfdelta(tdelta, fmt='%H:%M:%S'):
            d = {"D": tdelta.days}
            hours, rem = divmod(tdelta.seconds, 3600)
            minutes, seconds = divmod(rem, 60)
            d["H"] = '{:02d}'.format(hours)
            d["M"] = '{:02d}'.format(minutes)
            d["S"] = '{:02d}'.format(seconds)
            t = DeltaTemplate(fmt)
            return t.substitute(**d)

        # calculate elapsed time
        elapsed_time = None
        start_time = self.worker.start_time
        end_time = self.worker.end_time

        if start_time:
            if end_time:
                elapsed_time = end_time - start_time
            elif self.render_status() == RenderStatus.RUNNING:
                elapsed_time = datetime.now() - start_time

        elapsed_time_string = strfdelta(elapsed_time) if elapsed_time else "Unknown"
        return elapsed_time_string

    def frame_count(self):
        return self.worker.total_frames

    def work_path(self):
        return os.path.dirname(self.output_path)

    def file_list(self):
        job_dir = os.path.dirname(self.output_path)
        return glob.glob(os.path.join(job_dir, '*'))

    def log_path(self):
        return os.path.join(os.path.dirname(self.input_path), self.name + '.log')

    def percent_complete(self):
        return self.worker.percent_complete()

    @classmethod
    def generate_id(cls):
        return str(uuid.uuid4()).split('-')[0]