/*
 * 
 * Copyright 2005 the original author or authors.
 * 
 * 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 org.wamblee.crawler.kiss.main;

import java.util.ArrayList;
import java.util.EnumMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import java.util.TreeSet;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.dom4j.DocumentFactory;
import org.dom4j.Element;
import org.wamblee.crawler.kiss.guide.Program;
import org.wamblee.crawler.kiss.guide.Program.RecordingResult;

/**
 * Represents a report on the actions of the crawler.
 */
public class Report {

    private static final Log LOG = LogFactory
            .getLog(Report.class);

    /**
     * A map of category name to a set of program. Useful for displaying the
     * output of possibly interesting programs on a per category basis.
     */
    private Map<String, Set<Program>> _interestingShows;

    /**
     * Map or recording result to a set of programs.
     */
    private EnumMap<RecordingResult, Set<Program>> _recordings;

    /**
     * Messages generated while doing all the work.
     */
    private List<String> _messages;

    /**
     * Constructs the report.
     * 
     */
    public Report() {
        _interestingShows = new TreeMap<String, Set<Program>>();
        _recordings = new EnumMap<RecordingResult, Set<Program>>(
                RecordingResult.class);
        for (RecordingResult result : RecordingResult.values()) {
            _recordings.put(result, new TreeSet<Program>(
                    new Program.TimeComparator()));
        }
        _messages = new ArrayList<String>();
    }

    /**
     * Adds a message.
     * 
     * @param aMessage
     *            Message to add.
     */
    public void addMessage(String aMessage) {
        _messages.add(aMessage);
    }
    
    /**
     * Adds a message.
     * 
     * @param aMessage
     *            Message to add.
     * @param aException Exception that caused the problem.
     */
    public void addMessage(String aMessage, Exception aException) {
        String msg = aMessage; 
        for (Throwable e = aException; e != null; e = e.getCause()) {
            msg += ": " + e.getMessage(); 
        }
        addMessage(msg);
    }

    /**
     * Called to indicate that a program is interesting. 
     * 
     * @param aCategory
     *            Category of the program.
     * @param aProgram
     *            Program.
     */
    public void interestingProgram(String aCategory, Program aProgram) {
        LOG.info("category = '" + aCategory + "', program: " + aProgram);
        Set<Program> programs = _interestingShows.get(aCategory);
        if (programs == null) {
            programs = new TreeSet<Program>(new Program.TimeComparator());
            _interestingShows.put(aCategory, programs);
        }
        programs.add(aProgram);
    }
    
    /**
     * Called to specify the result of recording a program. 
     * @param aResult Result. 
     * @param aProgram Program. 
     */
    public void setRecordingResult(RecordingResult aResult, Program aProgram) { 
        _recordings.get(aResult).add(aProgram);   
    }

  
    /**
     * Get report as XML.
     * 
     * @return XML report
     */
    public Element asXml() {
        DocumentFactory factory = DocumentFactory.getInstance();
        Element report = factory.createElement("report");

        if (_messages.size() > 0) {
            Element messages = report.addElement("messages");
            for (String message : _messages) {
                messages.addElement("message").setText(message);
            }
        }

        Set<Program> reportedPrograms = new HashSet<Program>();

        for (RecordingResult result : RecordingResult.values()) {
            if (_recordings.get(result).size() > 0) {
                Element recordingResult = report.addElement("recorded")
                        .addAttribute("result", result.toString());

                for (Program program : _recordings.get(result)) {
                    recordingResult.add(program.asXml());
                    reportedPrograms.add(program);
                }
            }
        }

        if (_interestingShows.size() > 0) {
            Element interesting = report.addElement("interesting");
            for (String category : _interestingShows.keySet()) {
                Element categoryElem = interesting;
                if (category.length() > 0) {
                    categoryElem = interesting.addElement("category");
                    categoryElem.addAttribute("name", category);
                }
                for (Program program : _interestingShows.get(category)) {
                    if (!reportedPrograms.contains(program)) {
                        categoryElem.add(program.asXml());
                    } else {
                        LOG.info("Category '" + category + "', program "
                                + program + " already reported");
                    }
                }
                if (categoryElem.elements().size() == 0) {
                    // Remove empty category element.
                    LOG
                            .info("Removing element for category '" + category
                                    + "'");
                    interesting.remove(categoryElem);
                }
            }

        }

        return report;
    }
}