/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *    https://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License 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 org.grails.forge.api.create.zip;

import io.micronaut.context.event.ApplicationEventPublisher;
import io.micronaut.core.annotation.NonNull;
import io.micronaut.core.annotation.Nullable;
import io.micronaut.core.bind.annotation.Bindable;
import io.micronaut.core.io.Writable;
import io.micronaut.http.HttpHeaders;
import io.micronaut.http.HttpResponse;
import io.micronaut.http.MutableHttpResponse;
import io.micronaut.http.annotation.Controller;
import io.micronaut.http.annotation.Get;
import io.micronaut.http.annotation.Header;
import io.micronaut.scheduling.TaskExecutors;
import io.micronaut.scheduling.annotation.ExecuteOn;
import io.swagger.v3.oas.annotations.media.Content;
import io.swagger.v3.oas.annotations.responses.ApiResponse;
import org.grails.forge.api.DevelopmentReloading;
import org.grails.forge.api.create.AbstractCreateController;
import org.grails.forge.application.ApplicationType;
import org.grails.forge.application.Project;
import org.grails.forge.application.generator.GeneratorContext;
import org.grails.forge.application.generator.ProjectGenerator;
import org.grails.forge.io.ZipOutputHandler;
import org.grails.forge.options.BuildTool;
import org.grails.forge.options.GormImpl;
import org.grails.forge.options.JdkVersion;
import org.grails.forge.options.ServletImpl;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Pattern;
import java.io.IOException;
import java.io.OutputStream;
import java.io.Writer;
import java.nio.charset.Charset;
import java.util.List;

/**
 * Implements the {@link ZipCreateOperation} interface for applications.
 *
 * @author graemerocher
 * @since 6.0.0
 */
@Controller
@ExecuteOn(TaskExecutors.IO)
public class ZipCreateController extends AbstractCreateController implements ZipCreateOperation {

    public static final String MEDIA_TYPE_APPLICATION_ZIP = "application/zip";
    private static final Logger LOG = LoggerFactory.getLogger(ZipCreateController.class);

    /**
     * Default constructor.
     *
     * @param projectGenerator The project generator
     * @param eventPublisher   The event publisher
     */
    public ZipCreateController(ProjectGenerator projectGenerator, ApplicationEventPublisher eventPublisher) {
        super(projectGenerator, eventPublisher);
    }

    /**
     * Creates an application, generating a ZIP file as the response.
     *
     * @param type        The application type The application type
     * @param name        The name of the application The name of the application
     * @param features    The features The chosen features
     * @param build       The build tool
     * @param reloading   The development reloading option
     * @param gorm        The GORM
     * @param servlet     The Servlet
     * @param javaVersion The java version
     * @return A ZIP file containing the generated application.
     */
    @Override
    @Get(uri = "/create/{type}/{name}{?features,gorm,build,reloading,javaVersion}", produces = MEDIA_TYPE_APPLICATION_ZIP)
    @ApiResponse(
            description = "A ZIP file containing the generated application.",
            content = @Content(
                    mediaType = MEDIA_TYPE_APPLICATION_ZIP
            )
    )
    public HttpResponse<Writable> createApp(
            ApplicationType type,
            @Pattern(regexp = "[\\w\\d-_\\.]+") String name,
            @Nullable List<String> features,
            @Nullable BuildTool build,
            @Nullable DevelopmentReloading reloading,
            @Nullable GormImpl gorm,
            @Nullable ServletImpl servlet,
            @Nullable JdkVersion javaVersion,
            @Nullable @Header(HttpHeaders.USER_AGENT) String userAgent) {
        return generateAppIntoZipFile(type, name, features, build, reloading, gorm, servlet, javaVersion, userAgent);
    }

    /**
     * Creates the default application type using the name of the given Zip.
     *
     * @param type        The type
     * @param name        The ZIP name
     * @param features    The features
     * @param build       The build tool
     * @param reloading   The development reloading option
     * @param gorm        The GORM
     * @param servlet     The Servlet
     * @param javaVersion The java version
     * @param userAgent   The browser user-agent
     * @return A Zip file containing the application
     */
    @Get(uri = "/{name}.zip{?type,features,gorm,servlet,build,reloading}", produces = MEDIA_TYPE_APPLICATION_ZIP)
    @ApiResponse(
            description = "A ZIP file containing the generated application.",
            content = @Content(
                    mediaType = MEDIA_TYPE_APPLICATION_ZIP
            )
    )
    public HttpResponse<Writable> createZip(
            @Bindable(defaultValue = "WEB") ApplicationType type,
            @Pattern(regexp = "[\\w\\d-_]+") @NotBlank String name,
            @Nullable List<String> features,
            @Nullable BuildTool build,
            @Nullable DevelopmentReloading reloading,
            @Nullable GormImpl gorm,
            @Nullable ServletImpl servlet,
            @Nullable JdkVersion javaVersion,
            @Nullable @Header("User-Agent") String userAgent) {
        return generateAppIntoZipFile(type, name, features, build, reloading, gorm, servlet, javaVersion, userAgent);
    }

    public HttpResponse<Writable> generateAppIntoZipFile(
            @NotNull ApplicationType type,
            @NotNull String name,
            @Nullable List<String> features,
            @Nullable BuildTool buildTool,
            @Nullable DevelopmentReloading reloading,
            @Nullable GormImpl gorm,
            @Nullable ServletImpl servlet,
            @Nullable JdkVersion javaVersion,
            @Nullable String userAgent) {

        GeneratorContext generatorContext = createProjectGeneratorContext(type, name, features, buildTool, reloading, gorm, servlet, javaVersion, userAgent);
        MutableHttpResponse<Writable> response = HttpResponse.created(new Writable() {
            @Override
            public void writeTo(OutputStream outputStream, @Nullable Charset charset) throws IOException {
                try {
                    final Project project = generatorContext.getProject();
                    projectGenerator.generate(type,
                            project,
                            new ZipOutputHandler(project.getName(), outputStream),
                            generatorContext);

                    outputStream.flush();
                } catch (Exception e) {
                    LOG.error("Error generating application: " + e.getMessage(), e);
                    throw new IOException(e.getMessage(), e);
                }
            }

            @Override
            public void writeTo(Writer out) {
                // no-op, output stream used
            }
        });
        return response.header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=" + getFilename(generatorContext.getProject()));
    }

    /**
     * @param project The project
     * @return The file name to return.
     */
    protected @NonNull String getFilename(@NonNull Project project) {
        return project.getName() + ".zip";
    }
}
