/*
 * Copyright 2008 Google Inc.
 * 
 * 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.
 */

package com.google.doctool.custom;

import com.sun.javadoc.ClassDoc;
import com.sun.javadoc.DocErrorReporter;
import com.sun.javadoc.ExecutableMemberDoc;
import com.sun.javadoc.FieldDoc;
import com.sun.javadoc.PackageDoc;
import com.sun.javadoc.RootDoc;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;

/**
 * A doclet for using producing EZT output listing the specified classes and
 * their methods and constructors.
 */
public class EztDoclet {

  public static final String OPT_EZTFILE = "-eztfile";

  private static EztDoclet EZT_DOCLET;

  private static final String JAVADOC_URL = "https://docs.oracle.com/javase/8/docs/api/";

  public static int optionLength(String option) {
    if (option.equals(OPT_EZTFILE)) {
      return 2;
    }
    return 0;
  }

  public static boolean start(RootDoc root) {
    getDoclet().process(root);
    return true;
  }

  public static boolean validOptions(String[][] options,
      DocErrorReporter reporter) {
    return getDoclet().analyzeOptions(options, reporter);
  }

  private static EztDoclet getDoclet() {
    if (EZT_DOCLET == null) {
      EZT_DOCLET = new EztDoclet();
    }
    return EZT_DOCLET;
  }

  private String outputFile;

  private boolean analyzeOptions(String[][] options, DocErrorReporter reporter) {
    for (int i = 0; i < options.length; i++) {
      if (options[i][0] == OPT_EZTFILE) {
        outputFile = options[i][1];
      }
    }

    if (outputFile == null) {
      reporter.printError("You must specify an output filepath with "
          + OPT_EZTFILE);
      return false;
    }

    return true;
  }

  private String createFieldList(Collection<FieldDoc> fields) {
    StringBuffer buffer = new StringBuffer();
    Iterator<FieldDoc> iter = fields.iterator();
    while (iter.hasNext()) {
      FieldDoc field = iter.next();
      buffer.append(field.name());
      if (iter.hasNext()) {
        buffer.append(", ");
      }
    }
    return buffer.toString();
  }

  private String createMemberList(Collection<ExecutableMemberDoc> members) {
    StringBuffer buffer = new StringBuffer();
    Iterator<ExecutableMemberDoc> iter = members.iterator();
    while (iter.hasNext()) {
      ExecutableMemberDoc member = iter.next();
      buffer.append(member.name() + member.flatSignature());
      if (iter.hasNext()) {
        buffer.append(", ");
      }
    }
    return buffer.toString();
  }

  private void process(RootDoc root) {
    try {
      File outFile = new File(outputFile);
      outFile.getParentFile().mkdirs();
      FileWriter fw = new FileWriter(outFile);
      PrintWriter pw = new PrintWriter(fw, true);

      pw.println("<ol class=\"toc\" id=\"pageToc\">");
      for (PackageDoc pack : root.specifiedPackages()) {
        pw.format("  <li><a href=\"#Package_%s\">%s</a></li>\n",
            pack.name().replace('.', '_'), pack.name());
      }
      pw.println("</ol>\n");

      for (PackageDoc pack : root.specifiedPackages()) {
        pw.format("<h2 id=\"Package_%s\">Package %s</h2>\n",
            pack.name().replace('.', '_'), pack.name());
        pw.println("<dl>");

        String packURL = JAVADOC_URL + pack.name().replace(".", "/") + "/";

        // Sort the classes alphabetically
        ClassDoc[] classes = pack.allClasses(true);
        Arrays.sort(classes, new Comparator<ClassDoc>() {
          public int compare(ClassDoc arg0, ClassDoc arg1) {
            return arg0.name().compareTo(arg1.name());
          }
        });

        Iterator<ClassDoc> iter = Arrays.asList(classes).iterator();
        while (iter.hasNext()) {
          ClassDoc cls = iter.next();

          // Each class links to Sun's main JavaDoc
          pw.format("  <dt><a href=\"%s%s.html\">%s</a></dt>\n", packURL,
              cls.name(), cls.name());

          // Print out all fields
          Collection<FieldDoc> fields = new ArrayList<FieldDoc>();
          fields.addAll(Arrays.asList(cls.fields(true)));

          if (!fields.isEmpty()) {
            pw.format("  <dd style='margin-bottom: 0.5em;'>%s</dd>\n", createFieldList(fields));
          }

          // Print out all constructors and methods
          Collection<ExecutableMemberDoc> members = new ArrayList<ExecutableMemberDoc>();
          members.addAll(Arrays.asList(cls.constructors(true)));
          members.addAll(Arrays.asList(cls.methods(true)));

          if (!members.isEmpty()) {
            pw.format("  <dd>%s</dd>\n", createMemberList(members));
          }

          if (iter.hasNext()) {
            pw.print("\n");
          }
        }

        pw.println("</dl>\n");
      }
      pw.close();
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
  }
}