import pytest
import os

from datetime import datetime, timedelta
from netCDF4 import Dataset
import numpy as np
import random
import string

from tests.TestUtils import TestUtils
    
from SDToolBox import extract_waves, data_acquisition
from SDToolBox.data_acquisition import OutputData
import SDToolBox.outputmessages as output_messages


class Test_create:

    @pytest.mark.unittest
    def test_when_no_list_of_variables_given_then_exception_risen(self):
        output_result = None
        expected_error_message = \
            output_messages.error_missing_list_of_variables
        with pytest.raises(IOError) as e_info:
            output_result = OutputData(None)

        error_message = str(e_info.value)
        assert output_result is None
        assert error_message == expected_error_message, \
            'Expected {}'.format(expected_error_message) + \
            'but got {}'.format(error_message)

    @pytest.mark.unittest
    def test_when_list_of_variables_given_then_sets_data_dict(self):
        # 1. Given.
        var_list = ['dum', 'my']
        data_result = []
        # 2. When
        try:
            output_data = OutputData(var_list)
            data_result = output_data.get_data_dict()
        except Exception as e_info:
            pytest.fail(
                'Exception thrown but not expected. {}'.format(str(e_info)))

        # 3. Then
        assert data_result is not None
        assert data_result[output_data.var_time_key] is not None
        assert data_result[output_data.var_lon_key] is not None
        assert data_result[output_data.var_lat_key] is not None
        assert data_result[output_data.var_val_key] is not None
        variables_data = data_result[output_data.var_val_key]
        assert variables_data is not None
        assert set(variables_data.keys()) == set(var_list)


class Test_generate_wave_netcdf:

    @pytest.mark.systemtest
    def test_when_given_wave_cases_generates_output(self):
        # 1. Given
        # When using local data you can just replace the comment in these lines
        # dir_test_data = TestUtils.get_local_test_data_dir('netCDF_Waves_data')
        dir_test_data = 'P:\\metocean-data\\open\\ERA5\\data\\Global'

        input_data = data_acquisition.InputData()
        input_data.coord_list = [(4.2, 2.4), ]

        # 2. When
        extract_wave = extract_waves.ExtractWaves(input_data)
        output_data = extract_wave.subset_era_5(dir_test_data, 1981, 1982)

        try:
            netcdf = output_data.generate_wave_netcdf(
                dir_path=dir_test_data,
                base_name='test_wave',
                dataset_code=None,
                file_format='CF'
            )
        except Exception as e_info:
            pytest.fail(
                'Exception thrown but not expected. {}'.format(str(e_info)))

        # 3. Then
        assert netcdf is not None