import codecs
import io
import unittest
import unittest.mock
import gzip

import boto3
import moto
from botocore.exceptions import ClientError

from s3_uploader.copier.smart_stream_to_s3_decompress import Copier as SmartStreamToS3DecompressCopier


class SmartStreamToS3CopierTest(unittest.TestCase):

    @moto.mock_s3
    def test_copier_from_stream_to_s3_decompressed_gz(self):
        boto3.setup_default_session()
        conn = boto3.resource('s3', region_name='us-east-1')
        conn.create_bucket(Bucket='dev-sme-stream-transfer')

        expected = 'Some bytes data'
        data = bytes(expected, 'utf-8')

        expected_compressed = gzip.compress(data, 9)

        dest = {
            'bucket': 'dev-sme-stream-transfer',
            'key': 'test_file.gz'
        }
        decompressed_dest = {
            'bucket': 'dev-sme-stream-transfer',
            'key': 'test_file.txt'
        }

        copier = SmartStreamToS3DecompressCopier(
            unittest.mock.Mock(),
            io.BytesIO(expected_compressed),
            dest,
            decompressed_dest,
        )
        total = copier.copy()
        self.assertEqual(total, len(expected_compressed))

        actual_compressed = conn.Object(dest['bucket'], dest['key']).get()['Body'].read()
        self.assertEqual(actual_compressed, expected_compressed)

        actual_decompressed = conn.Object(decompressed_dest['bucket'], decompressed_dest['key']).get()['Body'].read().decode("utf-8")
        self.assertEqual(actual_decompressed, expected)

    @moto.mock_s3
    def test_copier_from_stream_to_s3_decompress_gz_only_decompress(self):
        boto3.setup_default_session()
        conn = boto3.resource('s3', region_name='us-east-1')
        conn.create_bucket(Bucket='dev-sme-stream-transfer')

        expected = 'Some bytes data'
        data = bytes(expected, 'utf-8')

        expected_compressed = gzip.compress(data, 9)

        dest = {
            'bucket': 'dev-sme-stream-transfer',
            'key': 'test_file.gz'
        }
        decompressed_dest = {
            'bucket': 'dev-sme-stream-transfer',
            'key': 'test_file.txt'
        }

        copier = SmartStreamToS3DecompressCopier(
            unittest.mock.Mock(),
            io.BytesIO(expected_compressed),
            dest,
            decompressed_dest,
            decompress_only=True
        )
        total = copier.copy()
        self.assertEqual(total, len(expected_compressed))

        self.assertRaises(ClientError, conn.Object(dest['bucket'], dest['key']).get)

        actual_decompressed = conn.Object(decompressed_dest['bucket'], decompressed_dest['key']).get()['Body'].read().decode("utf-8")
        self.assertEqual(actual_decompressed, expected)