"""Unit tests for Garcon CLI for backload_executor.py."""

import json
from unittest.mock import MagicMock, patch

import pytest

from feed_ingestion.bin import backload_executor


@pytest.fixture()
def mock_backload_executor_tasks():
    """Mock tasks in task_queue targeted for test_flow flow."""
    total_tasks = 10
    date = '2020-01-01'
    with patch('feed_ingestion.bin.backload_executor'
               '.BackloadTasksExecutor') as mock_backload_executor:
        mock_select_flows_to_process = mock_backload_executor.return_value.\
            __enter__.return_value.select_flows_to_process
        mock_select_flows_to_process.return_value = \
            [('test_flow', total_tasks)]

        def select_backload_tasks_by_flow(flow, limit):
            return [
                ('theorchard', date, '{}')
                for _ in range(min(limit, total_tasks))
            ]

        mock_select_backload_tasks_by_flow = \
            mock_backload_executor.return_value.__enter__\
            .return_value.select_backload_tasks_by_flow \
            = MagicMock(new=select_backload_tasks_by_flow)

        mock_select_backload_tasks_by_flow.side_effect = \
            select_backload_tasks_by_flow
        yield mock_backload_executor


@patch('feed_ingestion.bin.exec_flows.flows.get_flow')
@patch('feed_ingestion.bin.exec_flows.swf_util.'
       'count_running_workflows_by_type')
@pytest.mark.parametrize('limit, num_running_tasks, calls_expected', [
    (8, 10, 0),
    (8, 8, 0),
    (8, 2, 6),
    (8, 0, 8),
])
def test_start_tasks(
        mock_count_running_workflows_by_type, mock_get_flow,
        mock_backload_executor_tasks,
        limit, num_running_tasks, calls_expected):
    """Test limits."""
    # mock LIMITS
    mock_count_running_workflows_by_type.return_value = num_running_tasks
    mock_get_flow.domain = 'test'
    mock_get_flow.name = 'test_flow'

    with patch('feed_ingestion.bin.exec_flows.subprocess.call') as mock_call, \
            patch('feed_ingestion.bin.backload_executor._flow_limit') \
            as mock_limit:
        mock_limit.return_value = limit
        mock_call.return_value = 0
        backload_executor.start_tasks()
        assert mock_call.call_count == calls_expected


@patch('feed_ingestion.bin.exec_flows.flows.get_flow')
@patch('feed_ingestion.bin.exec_flows.swf_util.'
       'count_running_workflows_by_type')
@pytest.mark.parametrize('only_flows, calls_expected', [
    (['test_flow'], 7),
    (['other_flow'], 0),
    (['other_flow', 'also_other_flow'], 0),
    (['other_flow', 'test_flow'], 7),
])
def test_start_tasks_limit_only(
        mock_count_running_workflows_by_type, mock_get_flow,
        mock_backload_executor_tasks, only_flows, calls_expected):
    """Test when only limited flows are processing."""
    mock_count_running_workflows_by_type.return_value = 3
    mock_get_flow.domain = 'test'
    mock_get_flow.name = 'test_flow'

    with patch('feed_ingestion.bin.exec_flows.subprocess.call') as mock_call, \
            patch('feed_ingestion.bin.backload_executor._flow_limit') \
            as mock_limit:
        mock_limit.return_value = 10
        mock_call.return_value = 0
        backload_executor.start_tasks(only_flows=only_flows)
        assert mock_call.call_count == calls_expected


def test_flow_limit():
    """Test _flow_limit."""
    backload_executor.LIMIT_CONCURRENT_EXECUTIONS_BY_FLOW = {
        'specific_flow': 10,
        'DEFAULT': 5,
    }

    assert backload_executor._flow_limit('specific_flow') == 10
    assert backload_executor._flow_limit('other_flow') == 5


@patch('feed_ingestion.bin.exec_flows.flows.get_flow')
@patch('feed_ingestion.bin.exec_flows.swf_util.'
       'count_running_workflows_by_type')
def test_start_tasks_adds_backfill_to_context(
        mock_count_running_workflows_by_type, mock_get_flow,
        mock_backload_executor_tasks):
    """Test that backfill parameter is added to the context."""
    mock_count_running_workflows_by_type.return_value = 0
    mock_get_flow.domain = 'test'
    mock_get_flow.name = 'test_flow'

    with patch('feed_ingestion.bin.exec_flows.subprocess.call') as mock_call, \
            patch('feed_ingestion.bin.backload_executor._flow_limit') \
            as mock_limit:
        mock_limit.return_value = 1
        mock_call.return_value = 0

        backload_executor.start_tasks()

        call_args = mock_call.call_args[0][0]
        context_index = call_args.index('--context') + 1
        context = json.loads(call_args[context_index])
        assert context['backfill'] == 'True'