package software.amazon.logs.logstream;

import java.time.Duration;
import java.util.Collections;

import software.amazon.awssdk.services.cloudwatchlogs.CloudWatchLogsClient;
import software.amazon.awssdk.services.cloudwatchlogs.model.DescribeLogStreamsRequest;
import software.amazon.awssdk.services.cloudwatchlogs.model.DescribeLogStreamsResponse;
import software.amazon.awssdk.services.cloudwatchlogs.CloudWatchLogsClient;
import software.amazon.awssdk.services.cloudwatchlogs.model.InvalidParameterException;
import software.amazon.awssdk.services.cloudwatchlogs.model.ResourceNotFoundException;
import software.amazon.cloudformation.exceptions.CfnInvalidRequestException;
import software.amazon.cloudformation.exceptions.CfnNotFoundException;
import software.amazon.cloudformation.exceptions.*;
import software.amazon.awssdk.services.cloudwatchlogs.model.*;
import software.amazon.cloudformation.proxy.*;

import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Tag;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith;
import org.mockito.Mock;
import org.mockito.junit.jupiter.MockitoExtension;

import static org.assertj.core.api.Assertions.assertThat;
import static org.assertj.core.api.Assertions.assertThatThrownBy;

import static org.mockito.Mockito.*;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.atLeastOnce;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.verifyNoMoreInteractions;

@ExtendWith(MockitoExtension.class)
public class ReadHandlerTest extends AbstractTestBase {

    @Mock
    private AmazonWebServicesClientProxy proxy;

    @Mock
    private ProxyClient<CloudWatchLogsClient> proxyClient;

    @Mock
    CloudWatchLogsClient sdkClient;

    final ReadHandler handler = new ReadHandler();

    @BeforeEach
    public void setup() {
        proxy = new AmazonWebServicesClientProxy(logger, MOCK_CREDENTIALS, () -> Duration.ofSeconds(600).toMillis());
        sdkClient = mock(CloudWatchLogsClient.class);
        proxyClient = MOCK_PROXY(proxy, sdkClient);
    }

    @AfterEach
    public void tear_down(org.junit.jupiter.api.TestInfo testInfo) {
        if (testInfo.getTags().contains("noSdkInteraction")) {
            verify(sdkClient, never()).serviceName();
        } else {
            verify(sdkClient, atLeastOnce()).serviceName();
        }
        verifyNoMoreInteractions(sdkClient);
    }

    @Test
    public void handleRequest_SimpleSuccess() {

        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        final DescribeLogStreamsResponse describeResponse = DescribeLogStreamsResponse.builder()
                .logStreams(Translator.translateToSDK(model))
                .build();

        when(proxyClient.client().describeLogStreams(any(DescribeLogStreamsRequest.class)))
                .thenReturn(describeResponse);

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
            .desiredResourceState(model)
            .build();

        final ProgressEvent<ResourceModel, CallbackContext> response =
                handler.handleRequest(proxy, request, new CallbackContext(), proxyClient, logger);

        assertThat(response).isNotNull();
        assertThat(response.getStatus()).isEqualTo(OperationStatus.SUCCESS);
        assertThat(response.getCallbackDelaySeconds()).isEqualTo(0);
        assertThat(response.getResourceModel()).isEqualTo(request.getDesiredResourceState());
        assertThat(response.getResourceModels()).isNull();
        assertThat(response.getMessage()).isNull();
        assertThat(response.getErrorCode()).isNull();
    }

    @Test
    public void handleRequest_ResponseIsEmpty() {
        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        final DescribeLogStreamsResponse describeResponse = DescribeLogStreamsResponse.builder()
                .logStreams(Collections.emptyList())
                .build();

        when(proxyClient.client().describeLogStreams(any(DescribeLogStreamsRequest.class)))
                .thenReturn(describeResponse);

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        assertThatThrownBy(() -> handler.handleRequest(proxy, request, new CallbackContext(), proxyClient, logger))
                .isInstanceOf(CfnNotFoundException.class);

    }

    @Tag("noSdkInteraction")
    @Test
    public void handleRequest_LogGroupNameEmpty() {
        final ResourceModel model = ResourceModel.builder()
                .logStreamName("logStreamName")
                .build();

        final DescribeLogStreamsResponse describeResponse = DescribeLogStreamsResponse.builder()
                .logStreams(Collections.emptyList())
                .build();

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        final ProgressEvent<ResourceModel, CallbackContext> response = handler.handleRequest(proxy, request, new CallbackContext(), proxyClient, logger);

        assertThat(response).isNotNull();
        assertThat(response.getStatus()).isEqualTo(OperationStatus.FAILED);
        assertThat(response.getResourceModels()).isNull();
        assertThat(response.getErrorCode()).isEqualTo(HandlerErrorCode.InvalidRequest);

    }

    @Tag("noSdkInteraction")
    @Test
    public void handleRequest_ModelEmpty() {
        final ResourceModel model = ResourceModel.builder()
                .build();

        final DescribeLogStreamsResponse describeResponse = DescribeLogStreamsResponse.builder()
                .logStreams(Collections.emptyList())
                .build();

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        final ProgressEvent<ResourceModel, CallbackContext> response = handler.handleRequest(proxy, request, new CallbackContext(), proxyClient, logger);

        assertThat(response).isNotNull();
        assertThat(response.getStatus()).isEqualTo(OperationStatus.FAILED);
        assertThat(response.getResourceModels()).isNull();
        assertThat(response.getErrorCode()).isEqualTo(HandlerErrorCode.InvalidRequest);

    }


    @Test
    public void handleRequest_ResourceNotFound() {
        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        when(proxyClient.client().describeLogStreams(any(DescribeLogStreamsRequest.class)))
                .thenThrow(ResourceNotFoundException.class);

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        final ProgressEvent<ResourceModel, CallbackContext> response = handler
                .handleRequest(proxy, request, new CallbackContext(), proxyClient, logger);

        assertThat(response).isNotNull();
        assertThat(response.getStatus()).isEqualTo(OperationStatus.FAILED);
        assertThat(response.getResourceModels()).isNull();
        assertThat(response.getErrorCode()).isEqualTo(HandlerErrorCode.NotFound);

    }

    @Test
    public void handleRequest_ResourceNotFoundDescribeEmpty() {
        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        when(proxyClient.client().describeLogStreams(any(DescribeLogStreamsRequest.class)))
                .thenReturn(null);

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        assertThatThrownBy(() -> handler.handleRequest(proxy, request, new CallbackContext(), proxyClient, logger))
                .isInstanceOf(CfnNotFoundException.class);
    }

    @Test
    public void handleRequest_ResourceNotFoundDescribeNotEqualtoModel() {
        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        final ResourceModel model2 = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName2")
                .build();

        final DescribeLogStreamsResponse describeResponse = DescribeLogStreamsResponse.builder()
                .logStreams(Translator.translateToSDK(model2))
                .build();

        when(proxyClient.client().describeLogStreams(any(DescribeLogStreamsRequest.class)))
                .thenReturn(describeResponse);

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        assertThatThrownBy(() -> handler.handleRequest(proxy, request, new CallbackContext(), proxyClient, logger))
                .isInstanceOf(CfnNotFoundException.class);
    }

    @Test
    public void handleRequest_ExceptionThrown() {
        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        when(proxyClient.client().describeLogStreams(any(DescribeLogStreamsRequest.class)))
                .thenThrow(InvalidParameterException.class);

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        final ProgressEvent<ResourceModel, CallbackContext> response = handler
                .handleRequest(proxy, request, new CallbackContext(), proxyClient, logger);

        assertThat(response).isNotNull();
        assertThat(response.getStatus()).isEqualTo(OperationStatus.FAILED);
        assertThat(response.getResourceModels()).isNull();
        assertThat(response.getErrorCode()).isEqualTo(HandlerErrorCode.InvalidRequest);

    }

    @Test
    public void handleRequest_InternalError() {
        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        when(proxyClient.client().describeLogStreams(any(DescribeLogStreamsRequest.class)))
                .thenThrow(ServiceUnavailableException.class);

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        final ProgressEvent<ResourceModel, CallbackContext> response = handler
                .handleRequest(proxy, request, new CallbackContext(), proxyClient, logger);

        assertThat(response).isNotNull();
        assertThat(response.getStatus()).isEqualTo(OperationStatus.FAILED);
        assertThat(response.getResourceModels()).isNull();
        assertThat(response.getErrorCode()).isEqualTo(HandlerErrorCode.ServiceInternalError);
    }

    @Test
    public void handleRequest_LimitExceededException() {
        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        when(proxyClient.client().describeLogStreams(any(DescribeLogStreamsRequest.class)))
                .thenThrow(LimitExceededException.class);

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        final ProgressEvent<ResourceModel, CallbackContext> response = handler
                .handleRequest(proxy, request, new CallbackContext(), proxyClient, logger);

        assertThat(response).isNotNull();
        assertThat(response.getStatus()).isEqualTo(OperationStatus.FAILED);
        assertThat(response.getResourceModels()).isNull();
        assertThat(response.getErrorCode()).isEqualTo(HandlerErrorCode.ServiceLimitExceeded);
    }

    @Test
    public void handleRequest_GeneralServiceException() {
        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        when(proxyClient.client().describeLogStreams(any(DescribeLogStreamsRequest.class)))
                .thenThrow(CloudWatchLogsException.class);

        final ResourceHandlerRequest<ResourceModel> request = ResourceHandlerRequest.<ResourceModel>builder()
                .desiredResourceState(model)
                .build();

        final ProgressEvent<ResourceModel, CallbackContext> response = handler
                .handleRequest(proxy, request, new CallbackContext(), proxyClient, logger);

        assertThat(response).isNotNull();
        assertThat(response.getStatus()).isEqualTo(OperationStatus.FAILED);
        assertThat(response.getResourceModels()).isNull();
        assertThat(response.getErrorCode()).isEqualTo(HandlerErrorCode.GeneralServiceException);
    }

    @Tag("noSdkInteraction")
    @Test
    public void translateFromReadResponse() {

        final ResourceModel model = ResourceModel.builder()
                .logGroupName("logGroupName1")
                .logStreamName("logStreamName")
                .build();

        final DescribeLogStreamsResponse expectedResponse = DescribeLogStreamsResponse.builder()
                .build();

        final ResourceModel actualRequest = Translator.translateFromReadResponse(expectedResponse, model);

        assertThat(actualRequest).isNull();
    }

    @Tag("noSdkInteraction")
    @Test
    public void translateLogStreamTest() {

        final ResourceModel model = ResourceModel.builder()
                .logStreamName("logStreamName")
                .build();

        final ResourceModel actualRequest = Translator.translateLogStream(LogStream.builder().logStreamName("logStreamName").build());

        assertThat(actualRequest).isEqualToComparingFieldByField(model);
    }

}