/*
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */

package software.amazon.awssdk.transfer.s3;

import static org.assertj.core.api.Assertions.assertThat;
import static software.amazon.awssdk.testutils.service.S3BucketUtils.temporaryBucketName;

import java.io.File;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.TimeUnit;
import org.apache.commons.lang3.RandomStringUtils;
import org.junit.jupiter.api.AfterAll;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.Test;
import software.amazon.awssdk.core.ResponseBytes;
import software.amazon.awssdk.core.async.AsyncResponseTransformer;
import software.amazon.awssdk.core.async.ResponsePublisher;
import software.amazon.awssdk.services.s3.model.GetObjectResponse;
import software.amazon.awssdk.services.s3.model.PutObjectRequest;
import software.amazon.awssdk.testutils.RandomTempFile;
import software.amazon.awssdk.transfer.s3.model.CompletedDownload;
import software.amazon.awssdk.transfer.s3.model.CompletedFileDownload;
import software.amazon.awssdk.transfer.s3.model.Download;
import software.amazon.awssdk.transfer.s3.model.DownloadFileRequest;
import software.amazon.awssdk.transfer.s3.model.DownloadRequest;
import software.amazon.awssdk.transfer.s3.model.FileDownload;
import software.amazon.awssdk.transfer.s3.progress.LoggingTransferListener;
import software.amazon.awssdk.utils.Md5Utils;

public class S3TransferManagerDownloadIntegrationTest extends S3IntegrationTestBase {
    private static final String BUCKET = temporaryBucketName(S3TransferManagerDownloadIntegrationTest.class);
    private static final String KEY = "key";
    private static final int OBJ_SIZE = 18 * 1024 * 1024;
    private static File file;

    @BeforeAll
    public static void setup() throws IOException {
        createBucket(BUCKET);
        file = new RandomTempFile(OBJ_SIZE);
        s3.putObject(PutObjectRequest.builder()
                                     .bucket(BUCKET)
                                     .key(KEY)
                                     .build(), file.toPath());
    }

    @AfterAll
    public static void cleanup() {
        deleteBucketAndAllContents(BUCKET);
    }

    @Test
    void download_toFile() throws Exception {
        Path path = RandomTempFile.randomUncreatedFile().toPath();
        FileDownload download =
            tm.downloadFile(DownloadFileRequest.builder()
                                               .getObjectRequest(b -> b.bucket(BUCKET).key(KEY))
                                               .destination(path)
                                               .addTransferListener(LoggingTransferListener.create())
                                               .build());
        CompletedFileDownload completedFileDownload = download.completionFuture().get(1, TimeUnit.MINUTES);
        assertThat(Md5Utils.md5AsBase64(path.toFile())).isEqualTo(Md5Utils.md5AsBase64(file));
        assertThat(completedFileDownload.response().responseMetadata().requestId()).isNotNull();
    }

    @Test
    void download_toFile_shouldReplaceExisting() throws IOException {
        Path path = RandomTempFile.randomUncreatedFile().toPath();
        Files.write(path, RandomStringUtils.random(1024).getBytes(StandardCharsets.UTF_8));
        assertThat(path).exists();
        FileDownload download =
            tm.downloadFile(DownloadFileRequest.builder()
                                               .getObjectRequest(b -> b.bucket(BUCKET).key(KEY))
                                               .destination(path)
                                               .addTransferListener(LoggingTransferListener.create())
                                               .build());
        CompletedFileDownload completedFileDownload = download.completionFuture().join();
        assertThat(Md5Utils.md5AsBase64(path.toFile())).isEqualTo(Md5Utils.md5AsBase64(file));
        assertThat(completedFileDownload.response().responseMetadata().requestId()).isNotNull();
    }

    @Test
    void download_toBytes() throws Exception {
        Download<ResponseBytes<GetObjectResponse>> download =
            tm.download(DownloadRequest.builder()
                                       .getObjectRequest(b -> b.bucket(BUCKET).key(KEY))
                                       .responseTransformer(AsyncResponseTransformer.toBytes())
                                       .addTransferListener(LoggingTransferListener.create())
                                       .build());
        CompletedDownload<ResponseBytes<GetObjectResponse>> completedDownload = download.completionFuture().join();
        ResponseBytes<GetObjectResponse> result = completedDownload.result();
        assertThat(Md5Utils.md5AsBase64(result.asByteArray())).isEqualTo(Md5Utils.md5AsBase64(file));
        assertThat(result.response().responseMetadata().requestId()).isNotNull();
    }

    @Test
    void download_toPublisher() throws Exception {
        Download<ResponsePublisher<GetObjectResponse>> download =
            tm.download(DownloadRequest.builder()
                                       .getObjectRequest(b -> b.bucket(BUCKET).key(KEY))
                                       .responseTransformer(AsyncResponseTransformer.toPublisher())
                                       .addTransferListener(LoggingTransferListener.create())
                                       .build());
        CompletedDownload<ResponsePublisher<GetObjectResponse>> completedDownload = download.completionFuture().join();
        ResponsePublisher<GetObjectResponse> responsePublisher = completedDownload.result();
        ByteBuffer buf = ByteBuffer.allocate(Math.toIntExact(responsePublisher.response().contentLength()));
        CompletableFuture<Void> drainPublisherFuture = responsePublisher.subscribe(buf::put);
        drainPublisherFuture.join();
        assertThat(Md5Utils.md5AsBase64(buf.array())).isEqualTo(Md5Utils.md5AsBase64(file));
    }
}