import pytest
import os
from os import path
import netCDF4
from tests.TestUtils import TestUtils
from netCDF4 import Dataset
from SDToolBox import main as main
from SDToolBox import extract_waves
from SDToolBox import data_acquisition
import numpy as np


class Test_create:

    @pytest.mark.unittest
    def test_given_no_input_data_then_exception_is_risen(self):
        # 1. Given
        input_data = None
        output_result = None
        expected_error = 'No valid input data.'
        # 2. When
        with pytest.raises(IOError) as e_info:
            output_result = extract_waves.ExtractWaves(input_data)

        # 3. Then
        error_message = str(e_info.value)
        assert output_result is None
        assert error_message == expected_error, '' + \
            'Expected exception message {},'.format(expected_error) + \
            'retrieved {}'.format(error_message)


class Test_subset_era_5:

    @pytest.mark.systemtest
    def test_given_waves_folder_then_subset_collection_is_extracted(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)
        dataset_list = extract_wave.subset_era_5(dir_test_data, 1981, 1982)

        # 3. Then
        assert dataset_list is not None
        assert dataset_list['variables']['swh'] is not None

    @pytest.mark.systemtest
    def test_given_waves_folder_then_subset_collection_is_extracted_with_coord_list(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), (42, 2.4), (42, 24), (4.2, 24)]

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

        # 3. Then
        assert dataset_list is not None
    
    """
         Checks that the longitude is normalized if a value higher than 180 is passed
    """
    @pytest.mark.unittest
    def test_given_longitude_higher_than_180_returns_normalized_longitude(self):
        #setup
        longitude = 400
        normalized_longitude = longitude -180
        dir_test_data = 'P:\\metocean-data\\open\\ERA5\\data\\Global\\Hs'
        filename = 'era5_Global_Hs_1980.nc'
        path = dir_test_data + filename
        with Dataset(path, 'r', format='netCDF4') as case_dataset:
            input_data = data_acquisition.InputData()
            input_data.coord_list = [(4.2, 2.4)]
            extractwaves = extract_waves.ExtractWaves(input_data)
            
        #call
        result = extractwaves.check_for_longitude(longitude)
        #assert
        assert result == normalized_longitude
        
    """
        Checks that the longitude is unchanged if a value lower than 180 is passed
    """
    @pytest.mark.unittest
    def test_given_longitude_lower_than_180_returns_normalized_unchanged(self):
        longitude = 30
        dir_test_data = 'P:\\metocean-data\\open\\ERA5\\data\\Global\\Hs'
        filename = 'era5_Global_Hs_1980.nc'
        path = dir_test_data + filename
        with Dataset(path, 'r', format='netCDF4') as case_dataset:
            input_data = data_acquisition.InputData()
            input_data.coord_list = [(4.2, 2.4)]
            extractwaves = extract_waves.ExtractWaves(input_data)
            
        #call
        result = extractwaves.check_for_longitude(longitude)
        #assert
        assert result == 30

    """
        Checks that array of years if correctly generated
    """
    @pytest.mark.unittest
    def test_years_array_is_correctly_generated(self):
        #setup
        year1 = 1980
        yearN = 1983
        result_array = [1980,1981,1982,1983]
        result = []
        dir_test_data = 'P:\\metocean-data\\open\\ERA5\\data\\Global\\Hs'
        filename = 'era5_Global_Hs_1980.nc'
        path = dir_test_data + filename
        with Dataset(path, 'r', format='netCDF4') as case_dataset:
            input_data = data_acquisition.InputData()
            input_data.coord_list = [(4.2, 2.4)]
            extractwaves = extract_waves.ExtractWaves(input_data)
        #call
        result = extractwaves.generate_years_array(year1, yearN)
        #assert
        assert result[0] == result_array[0]
        assert result[1] == result_array[1]
        assert result[2] == result_array[2]
        assert result[3] == result_array[3]