/*
 * RatingData.java
 *
 * Created on April 11, 2006, 3:54 PM
 */
import java.text.MessageFormat;
import java.util.Locale;

/**
 * <p>A convenient demonstration data model for the Rating component. To use
 * multiple Rating instances in an application, one can create a 
 * <code>Map</code> of RatingData instances. In such a case, the 
 * <code>grade</code> property
 * of a rating instance could be bound as follows (where "rating1" is the key
 * used for the map entry):
 * </p>
 * <p>
 * <code>grade="#{SessionBean1.ratingMap.rating1.grade}"</code>
 * </p>
 * <p>
 * Here are the properties of a Rating component that can bind directly to the 
 * corresponding properties of a <code>RatingData</code> instance:
 * <code>grade</code>, <code>averageGrade</code>, <code>normalModeText</code>, 
 * <code>averageModeText</code>
 *  <code>gradeReadOnly</code>, <code>inAverageMode</code>, 
 *  <code>hoverTexts</code>.
 * </p>
 * <p>The methods of this class are synchronized to prevent simultaneous access
 * by multiple threads associated with the same session.</p>
 *
 * @author Matthew Bohm
 */
public class RatingData {
    
    /**
     *<p>The message formatting pattern to be used
     * for the average mode text.</p>
     */
    private static String averageModeTextPattern = "Average rating: {0,number,#.#} (from {1,number,integer} votes)";

    /**
     *<p>The normal mode text used when an appropriate hover text
     * is not available and a grade has not been saved.</p>
     */ 
    private static String simpleNormalModeText = "";

    /**
     *<p>The normal mode text used when an appropriate hover text
     * is not available and a grade has been saved.</p>
     */
    private static String simpleNormalModeTextSaved = "Saved";

    /**
     *<p>The normal mode text message formatting pattern used when an 
     * appropriate hover text is available and a grade has not been saved.</p>
     */
    private static String normalModeTextPattern = "My rating: {0}";

    /**
     *<p>The normal mode text message formatting pattern used when an 
     * appropriate hover text is available and a grade has been saved.</p>
     */
    private static String normalModeTextPatternSaved = "Saved: {0}";

    /**
     * <p>The "not interested" normal mode text when a grade has not
     * been saved.</p> 
     */
    private static String notInterestedNormalModeText = "My rating: Not interested";

    /**
     * <p>The "not interested" normal mode text when a grade has
     * been saved.</p> 
     */
    private static String notInterestedNormalModeTextSaved = "Saved: Not interested";

    /**
     * <p>The "clear" normal mode text when a grade has not
     * been saved.</p> 
     */
    private static String clearNormalModeText = "No rating assigned";

    /**
     * <p>The "clear" normal mode text when a grade has
     * been saved.</p> 
     */
    private static String clearNormalModeTextSaved = "No rating assigned";
    
    /**
     * <p>The message formatting object.</p> 
     */
    private MessageFormat mf;
    
    /**
     *<p>Construct a new <code>RatingData</code> instance and 
     * initialize the <code>normalModeText</code> and 
     * <code>averageModeText</code> properties.
     *</p>
     */
    public RatingData() {
        this.mf = new MessageFormat("");
        initDefaultTexts(false);     
    }
    
    /**
     *<p>Construct a new <code>RatingData</code> instance and 
     * initialize the <code>normalModeText</code> and 
     * <code>averageModeText</code> properties 
     * taking into account the hover texts.
     *</p>
     * @param hoverTexts The new hover texts.
     */
    public RatingData(String[] hoverTexts) {
        this.hoverTexts = hoverTexts;
        this.mf = new MessageFormat("");
        initDefaultTexts(false);        
    }
    
    /**
     *<p>Construct a new <code>RatingData</code> instance and 
     * initialize the <code>normalModeText</code> and 
     * <code>averageModeText</code> properties
     * taking into account the hover texts, 
     * grade, average grade, vote count, and whether
     * to show the grade as "saved."
     *</p>
     * @param hoverTexts The new hover texts.
     * @param grade The new grade.
     * @param averageGrade The new averageGrade.
     * @param voteCount The new number of user votes.
     * @param saved Whether to show the grade as "saved." 
     */
    public RatingData(String[] hoverTexts, int grade, double averageGrade, int voteCount, boolean saved) {
        this.hoverTexts = hoverTexts;
        this.grade = grade;
        this.averageGrade = averageGrade;
        this.voteCount = voteCount;
        this.mf = new MessageFormat("");
        initDefaultTexts(saved);     
    }
    
    /**
     *<p>Initialize the <code>normalModeText</code> and 
     * <code>averageModeText</code> properties taking into account the 
     * hover texts, grade, average grade, vote count, and whether
     * to show the grade as "saved."
     *</p>
     * @param saved Whether to show the grade as "saved." 
     */
    private void initDefaultTexts(boolean saved) {
        this.normalModeText = calculateNormalModeText(this.grade, saved);
        
        Object[] args = new Object[]{new Double(this.averageGrade), new Integer(this.voteCount)};
        mf.applyPattern(this.averageModeTextPattern);
        this.averageModeText = mf.format(args);
    }
    
    /**
     * <p>Get the locale used in message formatting the Rating texts.</p>
     */
    public synchronized Locale getLocale() {
        return this.mf.getLocale();
    }
    
    /**
     * <p>Set the locale used in message formatting the Rating texts.</p>
     */
    public synchronized void setLocale(Locale locale) {
        if (locale == null) {
            throw new NullPointerException();
        }
        this.mf.setLocale(locale);
    }
    
    private int grade;

    /**
     * Get the user's grade.
     * @return The user's grade.
     */
    public synchronized int getGrade() {

        return this.grade;
    }

    /**
     *<p>In addition to setting the grade, the following operations
     * will occur. The normal mode text
     * will be updated. Furthermore, if the new grade is
     * greater than 0 (since "not interested" is denoted by 1 and "clear"
     * is denoted by 0), the average grade will be updated by counting this
     * grade assignment as a vote. This is a crude algorithm, since it allows
     * a single user to vote multiple times. However, that is precisely what
     * we want for this demo. Along with this, the average mode text will be
     * updated accordingly, based on the new average grade. Also, if we are
     * assigning a non-zero grade, we set the gradeReadOnly entry for the
     * rating instace to True. In this way, by binding the rating instance's
     * <code>gradeReadOnly</code> property to the 
     * <code>gradeReadOnly</code> property of this <code>RatingData</code>,
     * you can lock the user's grade once the user assigns it. (If you don't
     * want this feature, simply don't bind the <code>gradeReadOnly</code> 
     * property to this <code>RatingData</code>.)</p>
     *<p>If the new grade is greater than 0, and the corresponding hover text 
     * is available, this method formats the normal mode text with that
     * hover text and grade as arguments. Otherwise, it sets the normal mode
     * text to the
     * <code>simpleNormalModeText</code>, 
     * <code>simpleNormalModeTextSaved</code>, 
     * <code>notInterestedNormalModeText</code>, 
     * <code>notInterestedNormalModeTextSaved</code>, 
     * <code>clearNormalModeText</code>, or
     * <code>clearNormalModeTextSaved</code> as appropriate, with no
     * formatting changes.
     * </p>
     * <p>
     * If the new grade is greater than 0, this method formats the average mode
     * text with the new average grade, vote count, and, if available, the 
     * corresponding hover text.
     *</p>
     * @param grade The new grade.
     */
    public synchronized void setGrade(int grade) {
        this.grade = grade;
        
        //update normalModeText
        String localNormalModeText = calculateNormalModeText(grade, true);
        setNormalModeText(localNormalModeText);

        if (grade > 0) {
            //update averageGrade with crude algorithm
            int localVoteCount = getVoteCount();
            double localAverageGrade = getAverageGrade();

            double totalGrade = localAverageGrade * localVoteCount;
            totalGrade += grade;
            localVoteCount++;
            localAverageGrade = totalGrade / localVoteCount;
            setVoteCount(localVoteCount);
            setAverageGrade(localAverageGrade);

            //update averageModeText
            Double averageGradeDouble = new Double(localAverageGrade);
            Integer voteCountInteger = new Integer(localVoteCount);
            String correspondingHoverText = null;

            //in case the pattern wants to make use of the corresponding hover text for this average grade
            if (this.hoverTexts != null) {
                int averageGradeAsInt = (int)Math.round(localAverageGrade);
                if (averageGradeAsInt > 0 && averageGradeAsInt <= this.hoverTexts.length) {
                    correspondingHoverText = this.hoverTexts[averageGradeAsInt - 1];
                }
            }

            Object[] args;
            if (correspondingHoverText == null) {
                args = new Object[]{averageGradeDouble, voteCountInteger};
            }
            else {
                args = new Object[]{averageGradeDouble, voteCountInteger, correspondingHoverText};
            }

            mf.applyPattern(this.averageModeTextPattern);
            String text = mf.format(args);
            setAverageModeText(text);
        }

        if (grade != 0) {
            //Set gradeReadOnly true. This will only take effect if the gradeReadOnly property is bound to this RatingData.
            //So if you want gradeReadOnly to be true once a grade is assigned, bind gradeReadOnly to this RatingData.
            //This enables you to "lock" the user's grade once the user assigns it.
            //If you don't want this feature, simply do not bind the gradeReadOnly property to this RatingData.
            setGradeReadOnly(true);
        }
    }

    private double averageGrade;

    /**
     * Get the average grade.
     * @return The average grade.
     */
    public synchronized double getAverageGrade() {

        return this.averageGrade;
    }

    /**
     * Set the average grade.
     * @param averageGrade The new average grade.
     */
    public synchronized void setAverageGrade(double averageGrade) {

        this.averageGrade = averageGrade;
    }

    private String normalModeText;

    /**
     * Get the normal mode text.
     * @return The normal mode text.
     */
    public synchronized String getNormalModeText() {

        return this.normalModeText;
    }

    /**
     * Set the normal mode text.
     * @param normalModeText The new normal mode text.
     */
    public synchronized void setNormalModeText(String normalModeText) {

        this.normalModeText = normalModeText;
    }

    private String averageModeText;

    /**
     * Get the average mode text.
     * @return The average mode text.
     */
    public synchronized String getAverageModeText() {

        return this.averageModeText;
    }

    /**
     * Set the average mode text.
     * @param averageModeText The new average mode text.
     */
    public synchronized void setAverageModeText(String averageModeText) {

        this.averageModeText = averageModeText;
    }

    private int voteCount;

    /**
     * Get the number of user votes.
     * @return The number of user votes.
     */
    public synchronized int getVoteCount() {

        return this.voteCount;
    }

    /**
     * Set the number of user votes.
     * @param voteCount The new number of user votes.
     */
    private void setVoteCount(int voteCount) {

        this.voteCount = voteCount;
    }

    private boolean gradeReadOnly;

    /**
     * Get whether the user's grade can be changed.
     * @return Whether the user's grade can be changed.
     */
    public synchronized boolean isGradeReadOnly() {

        return this.gradeReadOnly;
    }

    /**
     * Set whether the user's grade can be changed.
     * @param gradeReadOnly Whether the user's grade can be changed.
     */
    public synchronized void setGradeReadOnly(boolean gradeReadOnly) {

        this.gradeReadOnly = gradeReadOnly;
    }

    private boolean inAverageMode;

    /**
     * Get whether this <code>RatingData</code> is in average mode.
     * @return Whether this <code>RatingData</code> is in average mode.
     */
    public synchronized boolean isInAverageMode() {

        return this.inAverageMode;
    }

    /**
     * Set whether this <code>RatingData</code> is in average mode.
     * @param inAverageMode Whether this <code>RatingData</code> is in 
     * average mode.
     */
    public synchronized void setInAverageMode(boolean inAverageMode) {

        this.inAverageMode = inAverageMode;
    }

    private String[] hoverTexts;

    /**
     * Get the hover texts (i.e., for the "star" images only).
     * @return The hover texts.
     */
    public synchronized String[] getHoverTexts() {

        return this.hoverTexts;
    }

    /**
     * Set the hover texts (i.e., for the "star" images only).
     * @param hoverTexts The new hover texts.
     */
    public synchronized void setHoverTexts(String[] hoverTexts) {

        this.hoverTexts = hoverTexts;
    }
    
    /**
     *<p>Calculate a new normal mode text.</p>
     *@return A new normal mode text.
     */
    private String calculateNormalModeText(int localGrade, boolean saved) {
        String localNormalModeText = null;
        if (localGrade > 0) {
            if (hoverTexts != null && localGrade <= hoverTexts.length && hoverTexts[localGrade - 1] != null){
                Object[] args = {hoverTexts[localGrade - 1], new Integer(localGrade)};
                String pattern = saved ? this.normalModeTextPatternSaved : this.normalModeTextPattern;
                mf.applyPattern(pattern);
                localNormalModeText = mf.format(args);
            }
            else {
                localNormalModeText = saved ? this.simpleNormalModeTextSaved : this.simpleNormalModeText;
            }
        }
        if (localGrade == -1) {
            localNormalModeText = saved ? this.notInterestedNormalModeTextSaved : this.notInterestedNormalModeText;
        }
        else if (localGrade == 0) {
            localNormalModeText = saved ? this.clearNormalModeTextSaved : this.clearNormalModeText;
        }
        return localNormalModeText;
    }
}