/**
 *  Copyright 2005-2016 Red Hat, Inc.
 *
 *  Red Hat 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
 *
 *     http://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 io.fabric8.maven;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.lang.reflect.Field;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLStreamHandler;
import java.net.URLStreamHandlerFactory;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.EnumSet;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
import java.util.TreeSet;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.regex.Pattern;

import io.fabric8.agent.download.DownloadManager;
import io.fabric8.agent.download.DownloadManagers;
import io.fabric8.agent.model.BundleInfo;
import io.fabric8.agent.model.ConfigFile;
import io.fabric8.agent.model.Feature;
import io.fabric8.agent.model.Repository;
import io.fabric8.agent.service.Agent;
import io.fabric8.agent.service.MetadataBuilder;
import io.fabric8.common.util.MultiException;
import org.apache.felix.utils.version.VersionRange;
import org.apache.karaf.deployer.blueprint.BlueprintTransformer;
import org.apache.maven.artifact.Artifact;
import org.apache.maven.plugin.AbstractMojo;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.plugin.MojoFailureException;
import org.apache.maven.plugin.descriptor.PluginDescriptor;
import org.apache.maven.plugins.annotations.Component;
import org.apache.maven.plugins.annotations.Mojo;
import org.apache.maven.plugins.annotations.Parameter;
import org.eclipse.aether.RepositorySystem;
import org.osgi.framework.Constants;
import org.osgi.framework.ServiceReference;
import org.osgi.service.url.URLStreamHandlerService;

import static io.fabric8.agent.DeploymentAgent.getMetadata;
import static io.fabric8.agent.DeploymentAgent.getPrefixedProperties;
import static io.fabric8.agent.utils.AgentUtils.downloadRepositories;

@Mojo(name = "verify-features")
public class VerifyFeatureResolutionMojo extends AbstractMojo {

    @Parameter(property = "descriptors")
    private Set<String> descriptors;

    @Parameter(property = "features")
    private Set<String> features;

    @Parameter(property = "framework")
    private Set<String> framework;

    @Parameter(property = "distribution", defaultValue = "org.apache.karaf:apache-karaf")
    private String distribution;

    @Parameter(property = "javase")
    private String javase;

    @Parameter(property = "dist-dir")
    private String distDir;

    @Parameter(property = "additional-metadata")
    private File additionalMetadata;

    @Parameter(property = "fail")
    private String fail = "end";

    @Parameter(property = "verify-transitive")
    private boolean verifyTransitive = false;

    @Component
    protected PluginDescriptor pluginDescriptor;

    @Component
    protected RepositorySystem repositorySystem;

    @Override
    public void execute() throws MojoExecutionException, MojoFailureException {
        try {
            Field field = URL.class.getDeclaredField("factory");
            field.setAccessible(true);
            field.set(null, null);
        } catch (Exception e) {
            e.printStackTrace();
        }
        URL.setURLStreamHandlerFactory(new CustomBundleURLStreamHandlerFactory());

        System.setProperty("karaf.home", "target/karaf");
        System.setProperty("karaf.data", "target/karaf/data");


        ScheduledExecutorService executor = Executors.newScheduledThreadPool(8);

        Hashtable<String, String> properties = new Hashtable<>();

        if (additionalMetadata != null) {
            try (Reader reader = new FileReader(additionalMetadata)) {
                Properties metadata = new Properties();
                metadata.load(reader);
                for (Enumeration<?> e = metadata.propertyNames(); e.hasMoreElements(); ) {
                    Object key = e.nextElement();
                    Object val = metadata.get(key);
                    properties.put(key.toString(), val.toString());
                }
            } catch (IOException e) {
                throw new MojoExecutionException("Unable to load additional metadata from " + additionalMetadata, e);
            }
        }

        DownloadManager manager;
        MavenResolver resolver;
        final Map<String, Repository> repositories;
        Map<String, Feature[]> repos = new HashMap<>();
        Map<String, Feature> allFeatures = new HashMap<>();
        try {
            resolver = MavenResolvers.createMavenResolver(null, properties, "org.ops4j.pax.url.mvn", repositorySystem);
            manager = DownloadManagers.createDownloadManager(resolver, executor);
            repositories = downloadRepositories(manager, descriptors).call();
            for (String repoUri : repositories.keySet()) {
                Feature[] features = repositories.get(repoUri).getFeatures();
                // Ack features to inline configuration files urls
                for (Feature feature : features) {
                    for (BundleInfo bi : feature.getBundles()) {
                        String loc = bi.getLocation();
                        String nloc = null;
                        if (loc.contains("file:")) {
                            for (ConfigFile cfi : feature.getConfigurationFiles()) {
                                if (cfi.getFinalname().substring(1)
                                        .equals(loc.substring(loc.indexOf("file:") + "file:".length()))) {
                                    nloc = cfi.getLocation();
                                }
                            }
                        }
                        if (nloc != null) {
                            bi.setLocation(loc.substring(0, loc.indexOf("file:")) + nloc);
                        }
                    }
                    allFeatures.put(feature.getId(), feature);
                }
                repos.put(repoUri, features);
            }
        } catch (Exception e) {
            throw new MojoExecutionException("Unable to load features descriptors", e);
        }

        List<Feature> featuresToTest = new ArrayList<>();
        if (verifyTransitive) {
            for (Feature[] features : repos.values()) {
                featuresToTest.addAll(Arrays.asList(features));
            }
        } else {
            for (String uri : descriptors) {
                featuresToTest.addAll(Arrays.asList(repos.get(uri)));
            }
        }
        if (features != null && !features.isEmpty()) {
            StringBuilder sb = new StringBuilder();
            for (String feature : features) {
                if (sb.length() > 0) {
                    sb.append("|");
                }
                String p = feature.replaceAll("\\.", "\\\\.").replaceAll("\\*", ".*");
                sb.append(p);
                if (!feature.contains("/")) {
                    sb.append("/.*");
                }
            }
            Pattern pattern = Pattern.compile(sb.toString());
            for (Iterator<Feature> iterator = featuresToTest.iterator(); iterator.hasNext();) {
                Feature feature = iterator.next();
                String id = feature.getName() + "/" + feature.getVersion();
                if (!pattern.matcher(id).matches()) {
                    iterator.remove();
                }
            }
        }

        for (String fmk : framework) {
            properties.put("feature.framework." + fmk, fmk);
        }
        List<Throwable> failures = new ArrayList<>();
        for (Feature feature : featuresToTest) {
            try {
                String id = feature.getName() + "/" + feature.getVersion();
                manager = DownloadManagers.createDownloadManager(resolver, executor);
                verifyResolution(manager, allFeatures, id, properties);
                getLog().info("Verification of feature " + id + " succeeded");
            } catch (Exception e) {
                getLog().warn(e.getMessage());
                failures.add(e);
                if ("first".equals(fail)) {
                    throw e;
                }
            }
        }
        if ("end".equals(fail) && !failures.isEmpty()) {
            throw new MojoExecutionException("Verification failures", new MultiException("Verification failures", failures));
        }
    }

    private void verifyResolution(DownloadManager manager, Map<String, Feature> allFeatures, String feature, Hashtable<String, String> properties) throws MojoExecutionException {
        try {
            properties.put("feature.totest", feature);

            FakeSystemBundle systemBundle = getSystemBundleResource(getMetadata(properties, "metadata#"));
            FakeServiceReference profileHandlerSR = new FakeServiceReference(URLStreamHandlerService.class.getName(), "(url.handler.protocol=profile2)");
            systemBundle.setServiceReferences(URLStreamHandlerService.class.getName(), null, new ServiceReference[] {
                    profileHandlerSR
            });
            systemBundle.setService(profileHandlerSR, new Object());

            Agent agent = new Agent(null, systemBundle, manager);
            agent.setOptions(EnumSet.of(
                    io.fabric8.agent.service.Constants.Option.Simulate,
                    io.fabric8.agent.service.Constants.Option.Silent
            ));

            try {
                agent.provision(
                        allFeatures,
                        getPrefixedProperties(properties, "feature."),
                        getPrefixedProperties(properties, "bundle."),
                        getPrefixedProperties(properties, "req."),
                        getPrefixedProperties(properties, "override."),
                        getPrefixedProperties(properties, "optional."),
                        getMetadata(properties, "metadata#")
                );
            } catch (Exception e) {
                Set<String> resources = new TreeSet<>(manager.getProviders().keySet());
                throw new MojoExecutionException("Feature resolution failed for " + feature
                        + "\nMessage: " + e.toString()
                        + "\nResources: " + toString(resources), e);
            }


        } catch (MojoExecutionException e) {
            throw e;
        } catch (Exception e) {
            throw new MojoExecutionException("Error verifying feature " + feature + "\nMessage: " + e.getMessage(), e);
        }
    }

    private String toString(Collection<String> collection) {
        StringBuilder sb = new StringBuilder();
        sb.append("{\n");
        for (String s : collection) {
            sb.append("\t").append(s).append("\n");
        }
        sb.append("}");
        return sb.toString();
    }

    private FakeSystemBundle getSystemBundleResource(Map<String, Map<VersionRange, Map<String, String>>> metadata) throws Exception {
        Artifact karafDistro = pluginDescriptor.getArtifactMap().get(distribution);
        String dir = distDir;
        if (dir == null) {
            dir = karafDistro.getArtifactId() + "-" + karafDistro.getBaseVersion();
        }
        URL configPropURL = new URL("jar:file:" + karafDistro.getFile() + "!/" + dir + "/etc/config.properties");
        org.apache.felix.utils.properties.Properties configProps = PropertiesLoader.loadPropertiesFile(configPropURL, true);
//        copySystemProperties(configProps);
        if (javase == null) {
            configProps.put("java.specification.version", System.getProperty("java.specification.version"));
        } else {
            configProps.put("java.specification.version", javase);
        }
        configProps.substitute();

        Hashtable<String, String> headers = new Hashtable<>();
        headers.put(Constants.BUNDLE_MANIFESTVERSION, "2");
        headers.put(Constants.BUNDLE_SYMBOLICNAME, "system-bundle");
        headers.put(Constants.BUNDLE_VERSION, "0.0.0");

        String exportPackages = configProps.getProperty("org.osgi.framework.system.packages");
        if (configProps.containsKey("org.osgi.framework.system.packages.extra")) {
            if (!"".equals(configProps.getProperty("org.osgi.framework.system.packages.extra").trim())) {
                exportPackages += "," + configProps.getProperty("org.osgi.framework.system.packages.extra");
            }
        }
        headers.put(Constants.EXPORT_PACKAGE, exportPackages);

        String systemCaps = configProps.getProperty("org.osgi.framework.system.capabilities");
        headers.put(Constants.PROVIDE_CAPABILITY, systemCaps);

        new MetadataBuilder(metadata).overrideHeaders(headers);

        return new FakeSystemBundle(headers);
    }

    public static class CustomBundleURLStreamHandlerFactory implements URLStreamHandlerFactory {

        public URLStreamHandler createURLStreamHandler(String protocol) {
            if (protocol.equals("wrap")) {
                return new URLStreamHandler() {
                    @Override
                    protected URLConnection openConnection(URL url) throws IOException {
                        return new URLConnection(url) {
                            @Override
                            public void connect() throws IOException {
                            }

                            @Override
                            public InputStream getInputStream() throws IOException {
                                WrapUrlParser parser = new WrapUrlParser(url.getPath());
                                synchronized (CustomBundleURLStreamHandlerFactory.class) {
                                    return org.ops4j.pax.swissbox.bnd.BndUtils.createBundle(
                                            parser.getWrappedJarURL().openStream(),
                                            parser.getWrappingProperties(),
                                            url.toExternalForm(),
                                            parser.getOverwriteMode()
                                    );
                                }
                            }
                        };
                    }
                };
            } else if (protocol.equals("blueprint")) {
                return new URLStreamHandler() {
                    @Override
                    protected URLConnection openConnection(URL url) throws IOException {
                        return new URLConnection(url) {
                            @Override
                            public void connect() throws IOException {
                            }

                            @Override
                            public InputStream getInputStream() throws IOException {
                                try {
                                    ByteArrayOutputStream os = new ByteArrayOutputStream();
                                    BlueprintTransformer.transform(new URL(url.getPath()), os);
                                    os.close();
                                    return new ByteArrayInputStream(os.toByteArray());
                                } catch (Exception e) {
                                    throw (IOException) new IOException("Error opening blueprint xml url").initCause(e);
                                }
                            }
                        };
                    }
                };
            } else if (protocol.equals("war")) {
                return new org.ops4j.pax.url.war.Handler();
            } else {
                return null;
            }
        }

    }
}
