package sample.plugin;

/*
 * Copyright 2001-2005 The Apache Software Foundation.
 *
 * Licensed 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.
 */

import org.apache.maven.plugin.AbstractMojo;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.plugins.annotations.LifecyclePhase;
import org.apache.maven.plugins.annotations.Mojo;
import org.apache.maven.plugins.annotations.Parameter;
import org.apache.maven.project.MavenProject;

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintStream;
import java.nio.file.Files;
import java.nio.file.StandardCopyOption;

/**
 * Goal which touches a timestamp file.
 */
@Mojo(name = "header", defaultPhase = LifecyclePhase.PROCESS_SOURCES)
public class HeaderMojo extends AbstractMojo {

    @Parameter(defaultValue = "${project}", readonly = true)
    private MavenProject mavenProject;

    @Parameter(defaultValue = "index", property = "masterFile", required = true)
    private String masterFileName;

    @Parameter(defaultValue = "${project.build.directory}/sources", property = "outputDir", required = true)
    private File outputDir;

    private File baseDir;

    private File topicsFile;

    private File topicsDir;

    public void execute() throws MojoExecutionException {
        try {
            baseDir = mavenProject.getBasedir();

            copy(new File(baseDir, masterFileName + ".adoc"));
            copy(new File(baseDir, "topics.adoc"));

            File docInfo = new File(baseDir, "docinfo.html");
            if (docInfo.isFile()) {
                copy(docInfo);
                copy(new File(baseDir, "docinfo-footer.html"));
            }

            topicsDir = new File(baseDir, "topics");

            processTopics(topicsDir);
        } catch (IOException e) {
            e.printStackTrace();
            throw new MojoExecutionException(e.getMessage(), e);
        }
    }

    private void copy(File file) throws IOException {
        File out = new File(outputDir, file.getName());
        out.mkdirs();
        Files.copy(file.toPath(), out.toPath(), StandardCopyOption.REPLACE_EXISTING);
    }

    private void processTopics(File f) throws IOException {
        File out = new File(outputDir, f.getAbsolutePath().replaceFirst(topicsDir.getParentFile().getAbsolutePath(), ""));

        if (f.isFile() && f.getAbsolutePath().contains("/templates/")) {
            out.getParentFile().mkdirs();
            Files.copy(f.toPath(), out.toPath(), StandardCopyOption.REPLACE_EXISTING);
        } else if (f.isDirectory()) {
            for (File c : f.listFiles()) {
                processTopics(c);
            }
        } else if (f.getName().endsWith(".adoc")) {
            out.getParentFile().mkdirs();

            String filePath = f.getAbsolutePath().replace(baseDir.getParent(), "").substring(1);

            String includeHeaderPath = filePath.substring(baseDir.getName().length() + 7);
            includeHeaderPath = includeHeaderPath.substring(0, includeHeaderPath.lastIndexOf('/'));
            includeHeaderPath = includeHeaderPath.replaceAll("/[^/]+", "../");
            includeHeaderPath = includeHeaderPath + "templates/header.adoc";

            String header = "\n\n:include_filename: " + filePath + "\ninclude::" + includeHeaderPath + "[]\n\n";

            PrintStream ps = new PrintStream(new FileOutputStream(out));


            BufferedReader br = new BufferedReader(new FileReader(f));
            for (String l = br.readLine(); l != null; l = br.readLine()) {
                ps.println(l);
                if (l.contains("=")) {
                    break;
                }
            }

            ps.print(header);

            for (String l = br.readLine(); l != null; l = br.readLine()) {
                ps.println(l);
            }

            br.close();
            ps.close();
        }
    }
}