/*
 * 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
 *
 *   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 org.apache.maven.tools.plugin;

import java.io.File;
import java.net.URI;
import java.nio.file.FileSystem;
import java.nio.file.InvalidPathException;
import java.nio.file.Path;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.plugin.descriptor.PluginDescriptor;
import org.apache.maven.project.MavenProject;
import org.apache.maven.settings.Settings;
import org.codehaus.plexus.util.ReaderFactory;
import org.eclipse.aether.RepositorySystemSession;

/**
 * Default implementation of {@link PluginToolsRequest}, which is used to pass parameters to components used to extract
 * {@link org.apache.maven.plugin.descriptor.MojoDescriptor MojoDescriptor} instances from different types of metadata
 * for a given plugin.
 *
 * @author jdcasey
 * @since 2.5
 */
public class DefaultPluginToolsRequest implements PluginToolsRequest {

    private static final String DEFAULT_ENCODING = ReaderFactory.FILE_ENCODING;

    private PluginDescriptor pluginDescriptor;

    private MavenProject project;

    private String encoding = DEFAULT_ENCODING;

    private boolean skipErrorNoDescriptorsFound;

    private Set<Artifact> dependencies;

    private RepositorySystemSession repoSession;

    private URI internalJavadocBaseUrl;

    private String internalJavadocVersion;

    private List<URI> externalJavadocBaseUrls;

    private Settings settings;

    private String requiredJavaVersion;

    private String mavenApiVersion;

    private Collection<String> excludedScanDirectories;

    public DefaultPluginToolsRequest(MavenProject project, PluginDescriptor pluginDescriptor) {
        this.project = project;
        this.pluginDescriptor = pluginDescriptor;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public PluginDescriptor getPluginDescriptor() {
        return pluginDescriptor;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public PluginToolsRequest setPluginDescriptor(PluginDescriptor pluginDescriptor) {
        this.pluginDescriptor = pluginDescriptor;
        return this;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public MavenProject getProject() {
        return project;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public PluginToolsRequest setProject(MavenProject project) {
        this.project = project;
        return this;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public String getEncoding() {
        return this.encoding;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public PluginToolsRequest setEncoding(String encoding) {
        if (encoding != null && !encoding.isEmpty()) {
            this.encoding = encoding;
        } else {
            this.encoding = DEFAULT_ENCODING;
        }

        return this;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean isSkipErrorNoDescriptorsFound() {
        return skipErrorNoDescriptorsFound;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public PluginToolsRequest setSkipErrorNoDescriptorsFound(boolean skipErrorNoDescriptorsFound) {
        this.skipErrorNoDescriptorsFound = skipErrorNoDescriptorsFound;
        return this;
    }

    @Override
    public Set<Artifact> getDependencies() {
        if (this.dependencies == null) {
            this.dependencies = new HashSet<>();
        }
        return dependencies;
    }

    @Override
    public PluginToolsRequest setDependencies(Set<Artifact> dependencies) {
        this.dependencies = dependencies;
        return this;
    }

    @Override
    public RepositorySystemSession getRepoSession() {
        return repoSession;
    }

    public void setRepoSession(RepositorySystemSession repoSession) {
        this.repoSession = repoSession;
    }

    @Override
    public PluginToolsRequest setInternalJavadocBaseUrl(URI baseUrl) {
        internalJavadocBaseUrl = baseUrl;
        return this;
    }

    @Override
    public URI getInternalJavadocBaseUrl() {
        return internalJavadocBaseUrl;
    }

    @Override
    public PluginToolsRequest setInternalJavadocVersion(String javadocVersion) {
        this.internalJavadocVersion = javadocVersion;
        return this;
    }

    @Override
    public String getInternalJavadocVersion() {
        return internalJavadocVersion;
    }

    @Override
    public PluginToolsRequest setExternalJavadocBaseUrls(List<URI> javadocLinks) {
        this.externalJavadocBaseUrls = javadocLinks;
        return this;
    }

    @Override
    public List<URI> getExternalJavadocBaseUrls() {
        return externalJavadocBaseUrls;
    }

    @Override
    public PluginToolsRequest setSettings(Settings settings) {
        this.settings = settings;
        return this;
    }

    @Override
    public Settings getSettings() {
        return settings;
    }

    @Override
    public PluginToolsRequest setRequiredJavaVersion(String requiredJavaVersion) {
        this.requiredJavaVersion = requiredJavaVersion;
        return this;
    }

    @Override
    public String getRequiredJavaVersion() {
        return requiredJavaVersion;
    }

    @Override
    public PluginToolsRequest setUsedMavenApiVersion(String mavenApiVersion) {
        this.mavenApiVersion = mavenApiVersion;
        return this;
    }

    @Override
    public String getUsedMavenApiVersion() {
        return mavenApiVersion;
    }

    @Override
    public Collection<String> getExcludedScanDirectories() {
        if (excludedScanDirectories == null) {
            excludedScanDirectories = new HashSet<>();
        }
        return excludedScanDirectories;
    }

    @Override
    public void setExcludedScanDirectories(Collection<String> excludedScanDirectories) {
        this.excludedScanDirectories = excludedScanDirectories;
    }

    @Override
    public boolean isExcludedScanDirectory(File sourceFile) {
        return isExcluded(sourceFile.toPath(), getExcludedScanDirectories());
    }

    /**
     * Determines whether a source directory is covered by any of the configured exclusions.
     * <p>
     * Visible for testing: taking the directory as a {@link Path} keeps the whole decision tied to a single
     * {@link FileSystem}, so the behaviour on Windows separators can be exercised without running on Windows.
     *
     * @param sourceDirectory the source directory to check
     * @param excludedScanDirectories the configured exclusions, either plain directories or globs
     * @return true if excluded, false otherwise
     */
    static boolean isExcluded(Path sourceDirectory, Collection<String> excludedScanDirectories) {
        FileSystem fileSystem = sourceDirectory.getFileSystem();
        boolean windowsSeparators = "\\".equals(fileSystem.getSeparator());
        Path sourcePath = sourceDirectory.toAbsolutePath().normalize();
        for (String excludedScanDirectory : excludedScanDirectories) {
            if (excludedScanDirectory == null || excludedScanDirectory.isEmpty()) {
                // an empty entry would resolve to the working directory and exclude it silently
                continue;
            }
            // The documented form of this parameter is a plain directory, so compare as paths first. That
            // is safe with respect to separators, trailing separators and case on every file system.
            try {
                Path excludedPath = fileSystem
                        .getPath(excludedScanDirectory)
                        .toAbsolutePath()
                        .normalize();
                if (sourcePath.equals(excludedPath)) {
                    return true;
                }
            } catch (InvalidPathException e) {
                // not a plain directory - the Windows parser rejects wildcards, for instance - so it can
                // only ever have been meant as a glob
            }
            if (fileSystem
                    .getPathMatcher("glob:" + toGlobPattern(excludedScanDirectory, windowsSeparators))
                    .matches(sourcePath)) {
                return true;
            }
        }
        return false;
    }

    /**
     * Turns a configured exclusion into a glob pattern.
     * <p>
     * Configured values normally come from an interpolated property such as
     * <code>${project.build.directory}/generated-sources/annotations</code> and therefore hold backslashes on
     * Windows. A backslash is the escape character of the glob syntax and is swallowed by the pattern compiler
     * on every platform, so such a value could never match a real path, and one ending in a separator even
     * failed the build with a {@link java.util.regex.PatternSyntaxException}. A forward slash is compiled back
     * into the Windows separator, so it is the portable way to spell a separator in a glob.
     *
     * @param excludedScanDirectory the configured exclusion
     * @param windowsSeparators whether the file system separates names with a backslash
     * @return the pattern to hand to {@link FileSystem#getPathMatcher(String)}
     */
    static String toGlobPattern(String excludedScanDirectory, boolean windowsSeparators) {
        // On a file system that allows backslashes in names they may be a deliberate escape, so leave them be.
        return windowsSeparators ? excludedScanDirectory.replace('\\', '/') : excludedScanDirectory;
    }
}