"""Trending Tracks v2 flow."""

from datetime import datetime
from datetime import timedelta

from garcon import runner

from activity_detector.flows.base_flow import BaseFlow
from activity_detector.flows.trending_tracks_discrete import config
from activity_detector.flows.trending_tracks_discrete import tasks


class Flow(BaseFlow):
    """Class representing the workflow."""

    def __init__(self):
        """Initiailze flow object."""
        super(Flow, self).__init__(
            flow_name=config.SWF_FLOW_NAME,
            version=config.SWF_FLOW_VERSION
        )

    def workflow_id(self, initial_context):
        """Override workflow id to match default date selection.

        Args:
            initial_context (dict): The initial context for the flow.

        Returns:
            str: A unique identifier for a workflow
        """
        if 'context_date' not in initial_context:
            date = (datetime.today() - timedelta(
                    days=config.DEFAULT_SHIFT_DAYS)).strftime('%Y-%m-%d')
        else:
            date = initial_context['context_date']

        return '{flow_name}-{date}'.format(flow_name=self.name, date=date)

    def decider(self, schedule, context):
        """Activity decider.

        Args:
            schedule (callable): scheduler method
            context (dict): flow initial context

        """
        bootstrap = schedule('bootstrap', self.bootstrap)

        check_dynamo_status = schedule(
            'check_dynamo_status',
            self.check_dynamo_status,
            requires=[bootstrap])

        if check_dynamo_status.result.get(
                'check_dynamo_status.should_run') is False:
            return

        detect_spikes = schedule(
            'detect_spikes',
            self.detect_spikes,
            requires=[check_dynamo_status]
        )

        schedule(
            'set_dynamo_status',
            self.set_dynamo_status,
            requires=[detect_spikes]
        )

    @property
    def bootstrap(self):
        """Bootstrap initial configuration."""
        return self.create(
            name='bootstrap',
            tasks=runner.Sync(
                tasks.bootstrap.fill(
                    namespace='bootstrap',
                    date='context_date',
                    run_id='execution.run_id')))

    @property
    def check_dynamo_status(self):
        """Check dynamo status."""
        return self.create(
            name='check_dynamo_status',
            tasks=runner.Sync(
                tasks.check_dynamo_status.fill(
                    namespace='check_dynamo_status',
                    date='bootstrap.target_date')))

    @property
    def detect_spikes(self):
        """Query for trending track spikes."""
        return self.create(
            name='detect_spikes',
            tasks=runner.Sync(
                tasks.detect_spikes.fill(
                    namespace='detect_spikes',
                    date='bootstrap.target_date')))

    @property
    def set_dynamo_status(self):
        """Set activity status."""
        return self.create(
            name='set_dynamo_status',
            tasks=runner.Sync(
                tasks.set_dynamo_status.fill(
                    namespace='set_dynamo_status',
                    date='bootstrap.target_date',
                    failures='detect_spikes.failures')))