/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * See LICENSE.txt included in this distribution for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at LICENSE.txt.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2007, 2012, Oracle and/or its affiliates. All rights reserved.
 * Portions Copyright 2012 Jens Elkner.
 */

package org.opensolaris.opengrok.history;

import java.util.ArrayList;
import java.util.Date;
import java.util.Set;
import java.util.TreeMap;
import java.util.logging.Logger;

import org.opensolaris.opengrok.web.Util;

/**
 * Class representing file annotation, i.e., revision and author for the last
 * modification of each line in the file.
 */
public class Annotation {

    private final ArrayList<Integer> lines = new ArrayList<Integer>();
    private ArrayList<RevInfo> infos = new ArrayList<RevInfo>();
    private TreeMap<String,Integer> rev2rid = new TreeMap<String,Integer>();
    private int widestRevision;
    private int widestAuthor;
    private final String filename;
    static final Logger log = Logger.getLogger(Annotation.class.getName());

    /**
     * Create a new instance.
     * @param filename  the basename of the associated file.
     */
    public Annotation(String filename) {
        this.filename = filename;
    }

    private final int getRID(int line) {
        if (line > lines.size()) {
            return -1;
        }
        return lines.get(line-1).intValue();
    }

    /**
     * Gets the revision for the last change to the specified line.
     *
     * @param line line number (counting from 1)
     * @return revision string, or an empty string if there is no information
     * about the specified line
     */
    public String getRevision(int line) {
        int idx = getRID(line);
        return idx < 0 ? "" : infos.get(idx).rev;
    }

    /**
     * Gets all revisions that are in use, first is the lowest one (sorted using 
     * natural order)
     *
     * @return list of all revisions the file has
     */
    public Set<String> getRevisions() {
        return rev2rid.keySet();
    }

    /**
     * Gets the author who last modified the specified line.
     *
     * @param line line number (counting from 1)
     * @return author, or an empty string if there is no information about the
     * specified line
     */
    public String getAuthor(int line) {
        int idx = getRID(line);
        return idx < 0 ? "" : infos.get(idx).author;
    }

    /**
     * Returns the size of the file (number of lines).
     *
     * @return number of lines
     */
    public int size() {
        return lines.size();
    }

    /**
     * Returns the widest revision string in the file (used for pretty
     * printing).
     *
     * @return number of characters in the widest revision string
     */
    public int getWidestRevision() {
        return widestRevision;
    }

    /**
     * Returns the widest author name in the file (used for pretty printing).
     *
     * @return number of characters in the widest author string
     */
    public int getWidestAuthor() {
        return widestAuthor;
    }

    private class RevInfo {
        String rev;         // revision column in html view
        String author;      // email aka author column in html view
        Desc desc;           // tooltip infos
        public RevInfo(String rev, String author, Desc desc) {
            this.rev = rev;
            this.author = author;
            this.desc = desc;
        }
    }
    
    
    /**
     * Adds a line to the file. Invokeing concurrently causes unpredictable
     * results.
     * 
     * @param revision revision number
     * @param author author name
     */
    void addLine(String revision, String author) {
        if (revision == null) {
            revision = "";
        }
        if (author == null) {
            author = "";
        }
        Integer rid = rev2rid.get(revision);
        if (rid == null) {
            RevInfo info = new RevInfo(revision, author, null);
            rid = Integer.valueOf(infos.size());
            rev2rid.put(revision, rid);
            infos.add(info);
            widestRevision = Math.max(widestRevision, revision.length());
            widestAuthor = Math.max(widestAuthor, info.author.length());
        }
        lines.add(rid);
    }

    private class Desc {
        String changeset;
        String msg;
        String html;
        String user;
        Date date;
        static final String EOL = "&lt;br/&gt;";
        static final String BR = "<br/>";
        /**
         * Converts different html special characters into their encodings used in
         * html. Currently used only for tooltips of annotation revision number view
         *
         * @param s
         *            input text
         * @return encoded text for use in <a title=""> tag
         */
        private final String encode(String s, String newline) {
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < s.length(); i++ ) {
                char c = s.charAt(i);
                switch (c) {
                    case '\\':
                        sb.append("&#92;");
                        break;
                    case '"':
                        sb.append("&quot;");
                        break; // \\\"
                    case '&':
                        sb.append("&amp;");
                        break;
                    case '>':
                        sb.append("&gt;");
                        break;
                    case '<':
                        sb.append("&lt;");
                        break;
                    case ' ':
                        sb.append("&nbsp;");
                        break;
                    case '\t':
                        sb.append("&nbsp;&nbsp;&nbsp;&nbsp;");
                        break;
                    case '\n':
                        sb.append(newline);
                        break;
                    case '\r':
                        break;
                    default:
                        sb.append(c);
                        break;
                }
            }
            return sb.toString();
        }

        Desc(String changeset, String msg, String user, Date date) {
            this.changeset = changeset;
            this.msg = msg;
            this.user = user;
            this.date = date;
        }
        
        String getHtml() {
            if (html == null) {
                html = "changeset: " + encode(changeset, EOL) + EOL
                    + "summary: " + encode(msg, EOL) + EOL 
                    + "user: " + encode(user, EOL) + EOL 
                    + "date: " + date;
            }
            return html;
        }
        
        String getJson() {
            // not stored because usually called once only
            return 
                  "<b>Changeset</b>: " + encode(changeset, BR) + BR
                + "<b>Summary</b>: " + encode(msg, BR) + BR 
                + "<b>User</b>: " + encode(user, BR) + BR 
                + "<b>Date</b>: " + date;
        }
    }
    /**
     * Add the full commit message to the given revision. Ignored if there is
     * no revision, which may accommodate this message (add an appropriate line
     * before, if desired).
     * @param revision  revision in question.
     * @param description   full commit message to add (gets automatically html
     *  escaped including newlines, which are translated into '&gt;br/&lt;).
     */
    void addDesc(String revision, String changeset, String msg, String user, 
        Date date) 
    {
        Integer rid = rev2rid.get(revision);
        if (rid != null) {
            RevInfo info = infos.get(rid.intValue());
            if (info != null) {
                info.desc = new Desc(changeset, msg, user, date);
            }
        }
    }

    /**
     * Get the full commit message for the given revision.
     * @param revision  revision in question.
     * @return {@code null} if not found, the html escaped commit message 
     *  otherwise.
     */
    public String getDesc(String revision) {
        Integer idx = rev2rid.get(revision);
        return idx == null ? null : infos.get(idx.intValue()).desc.getHtml();
    }

    /**
     * Get the basename of the associated source file.
     * @return a filename
     * @see Annotation#Annotation(String)
     */
    public String getFilename() {
        return filename;
    }

    /**
     * Convert this annotation data into compact JSON format.
     * @return a JSON Object.
     */
    public String toJson() {
        StringBuilder buf = new StringBuilder(256)
            .append("{\"uri\":\"").append(Util.uriEncodePath(filename))
            .append("\",\"lines\":").append(lines.size())
            .append(",\"line2rev\":[");
        if (lines.size() > 0) {
            Integer lastRid = Integer.valueOf(-1);
            int count = 0;
            for (Integer rid : lines) {
                count++;
                if (rid.intValue() == lastRid.intValue()) {
                    continue;
                }
                buf.append(count).append(',').append(rid).append(',');
                lastRid = rid;
            }
            buf.setLength(buf.length()-1);  // delete last ,
        }
        buf.append("], \"revs\": [");
        if (infos.size() > 0) {
            for (RevInfo info : infos) {
                buf.append("{\"rev\":").append(Util.jsStringLiteral(info.rev))
                    .append(",\"author\":").append(Util.jsStringLiteral(info.author))
                    .append(",\"msg\":\"").append(info.desc.getJson())
                    .append("\"},");
            }
            buf.setLength(buf.length()-1);
        }        
        return buf.append("]}").toString();
    }
}