package com.digi.config.util;

import java.io.*;
import java.text.MessageFormat;
import java.util.*;
import javax.swing.ImageIcon;
import java.net.URL;


/**
 *  This class provides static helper methods for accessing the various resource
 *  bundles available in the config system.
 *
 */
public class ConfigResource {

    //==============================================================================
    //=                  Static attributes
    //==============================================================================
    /** Singleton reference */
    static ConfigResource theInstance = null;

    /**
     * Singleton accessor method
     */
    public static ConfigResource getInstance() {
        if (theInstance==null) {
            theInstance = new ConfigResource();
        }
        return theInstance;
    }

    /** The default resource files */
    public static final String DFT_MSG_TEXT_BUNDLE_NAME  = "com.digi.config.resources.CommonResourceBundle";
    public static final String DFT_UI_TEXT_BUNDLE_NAME   = "com.digi.config.resources.CommonUiResourceBundle";
    public static final String DFT_UI_IMAGE_BUNDLE_NAME  = "com.digi.config.resources.CommonImgResourceBundle";
    public static final String DFT_HELP_TEXT_BUNDLE_NAME = "com.digi.config.resources.CommonHelpResourceBundle";

    /** The location of the image files */
    private static String imagesDirectory="/com/digi/config/images/";

    public static void setImagesDirectory(String directory) {
        imagesDirectory = directory;
    }

    //==============================================================================
    //=                  Instance attributes
    //==============================================================================
    // Vector of resource bundles to lookup resources in. Start looking at top of list and work way down till resource found.
    Vector msgTextRbList;
    Vector uiTextRbList;
    Vector uiImageRbList;
    Vector helpTextRbList;



    /** Cache of loaded images so don't load multiple times */
    private static Map imageMap=new HashMap();




    protected ConfigResource() {
        // Define the ResourceBundle stacks 
        msgTextRbList = new Vector();
        uiTextRbList = new Vector();
        uiImageRbList = new Vector();
        helpTextRbList = new Vector();

        // populate Rb Vectors with the default bundles
        _loadMsgTextRb(DFT_MSG_TEXT_BUNDLE_NAME);
        _loadUiTextRb(DFT_UI_TEXT_BUNDLE_NAME);
        _loadUiImageRb(DFT_UI_IMAGE_BUNDLE_NAME);
        _loadHelpTextRb(DFT_HELP_TEXT_BUNDLE_NAME);
    }


    /**
     * load the specified resource bundle and push it onto the message text resource stack.
     */
    public void _loadMsgTextRb(String bundleName) {
        try {
            ResourceBundle rb=ResourceBundle.getBundle(bundleName);
            msgTextRbList.add(0,rb);
        }
        catch (MissingResourceException exc) {
            SystemLog.log("MissingBundle", new Serializable[] {bundleName}, new Serializable[] {exc});
        }
    }

    /**
     * load the specified resource bundle and push it onto the UI text resource stack.
     */
    public void _loadUiTextRb(String bundleName) {
        try {
            ResourceBundle rb=ResourceBundle.getBundle(bundleName);
            uiTextRbList.add(0,rb);
        }
        catch (MissingResourceException exc) {
            SystemLog.log("MissingBundle", new Serializable[] {bundleName}, new Serializable[] {exc});
        }
    }

    /**
     * load the specified resource bundle and push it onto the UI image resource stack.
     */
    public void _loadUiImageRb(String bundleName) {
        try {
//            ImageResourceBundle rb= new ImageResourceBundle(bundleName);
            ResourceBundle rb=ResourceBundle.getBundle(bundleName);
            uiImageRbList.add(0,rb);
        }
        catch (MissingResourceException exc) {
            SystemLog.log("MissingBundle", new Serializable[] {bundleName}, new Serializable[] {exc});
        }
    }

    /**
     * load the specified resource bundle and push it onto the help text resource stack.
     */
    public void _loadHelpTextRb(String bundleName) {
        try {
            ResourceBundle rb=ResourceBundle.getBundle(bundleName);
            helpTextRbList.add(0,rb);
        }
        catch (MissingResourceException exc) {
            SystemLog.log("MissingBundle", new Serializable[] {bundleName}, new Serializable[] {exc});
        }
    }

    //
    // Static helper methods for loading new resource files
    //

    /**
     * load the specified resource bundle and push it onto the message text resource stack.
     */
    public static void loadMsgTextRb(String bundleName) {
        getInstance()._loadMsgTextRb(bundleName);
    }
    /**
     * load the specified resource bundle and push it onto the UI text resource stack.
     */
    public static void loadUiTextRb(String bundleName) {
        getInstance()._loadUiTextRb(bundleName);
    }
    /**
     * load the specified resource bundle and push it onto the UI image resource stack.
     */
    public static void loadUiImageRb(String bundleName) {
        getInstance()._loadUiImageRb(bundleName);
    }
    /**
     * load the specified resource bundle and push it onto the help text resource stack.
     */
    public static void loadHelpTextRb(String bundleName) {
        getInstance()._loadHelpTextRb(bundleName);
    }




    /**
     * Fetches a string from a message text resource bundle. Search the resource bundle stack from the
     * top to the bottom until the message is found. 
     * Note: If the message is not located, then the key value is returned.
     *
     * @param key to use to get text from the resource bundle
     * @return the requested message or the key if the text is missing
     */
    public static String getMsgRbString(String key) {
        try {
            return getMsgRbStringForce(key);
        } catch (MissingResourceException e) {
            //SystemLog.log("MissingBundleKey", new Serializable[] { DFT_MSG_TEXT_BUNDLE_NAME, key }, new Serializable[] { exc });
        }
        return key;
    }

    /**
     * Fetches a string from a message text resource bundle. Search the resource bundle stack from the
     * top to the bottom until the message is found. 
     * Note: If the message is not located, then a MissingResourceException is thrown
     *
     * @param key to use to get text from the resource bundle
     * @return the requested message
     */
    public static String getMsgRbStringForce(String key) throws MissingResourceException {
        MissingResourceException mre = null;
        String localizedString=null;
        for (Iterator i=getInstance().msgTextRbList.iterator(); (localizedString==null) && i.hasNext();) {
            ResourceBundle rb = (ResourceBundle)i.next();
            try {
                localizedString = rb.getString(key);
            } catch (MissingResourceException exc) {
                mre = exc;
            }
        }
        if ((localizedString==null) && (mre!=null)) { // didn't find the msg in any of the resource bundles
            throw mre;
        }
        return localizedString;
    }

    /**
     * Fetches a string from a message text resource bundle. Search the resource bundle stack from the
     * top to the bottom until the message is found. The messeage is then formatted with the supplied 
     * parameters.
     * Note: If the message is not located, then the key value is returned.
     *
     *
     * @param key to use to get text from the resource bundle
     * @param replacementValues is an array of replacement values to insert into the message.
     * @return the requested message or the key is the text is missing
     */
    public static String getMsgRbString(String key, Object[] replacementValues) {
        String localizedString;
        localizedString = getMsgRbString(key);
        if (!localizedString.equals(key)) {
            localizedString=MessageFormat.format(localizedString,replacementValues);
        }
        return localizedString;
    }


    /**
     * Fetches a string from a ui text resource bundle. Search the resource bundle stack from the
     * top to the bottom until the message is found. 
     * Note: If the message is not located, then the key value is returned.
     *
     * @param key to use to get text from the resource bundle
     * @return the requested message or the key if the text is missing
     */
    public static String getUiRbString(String key) {
        String localizedString=null;
        for (Iterator i=getInstance().uiTextRbList.iterator(); (localizedString==null) && i.hasNext();) {
            ResourceBundle rb = (ResourceBundle)i.next();
            try {
                localizedString = rb.getString(key);
            } catch (MissingResourceException exc) {
            }
        }
        if (localizedString==null) {
            localizedString=key;
            //SystemLog.log("MissingBundleKey", new Serializable[] { DFT_UI_TEXT_BUNDLE_NAME, key }, new Serializable[] { exc });
        }
        return localizedString;
    }

    /**
     * Fetches a string from a ui text resource bundle. Search the resource bundle stack from the
     * top to the bottom until the message is found. The messeage is then formatted with the supplied 
     * parameters.
     * Note: If the message is not located, then the key value is returned.
     *
     * @param key to use to get text from the resource bundle
     * @param replacementValues is an array of replacement values to insert into the message.
     * @return the requested message or the key is the text is missing
     */
    public static String getUiRbString(String key, Object[] replacementValues) {
        String localizedString;
        localizedString = getUiRbString(key);
        if (!localizedString.equals(key)) {
            localizedString=MessageFormat.format(localizedString,replacementValues);
        }
        return localizedString;
    }


    /**
     * Fetches a image from a ui image resource bundle. Search the resource bundle stack from the
     * top to the bottom until the image is found. 
     * Note: If the image is not located, then the value null is returned.
     *
     * @param key to use to get text from the resource bundle
     * @return the requested image or null if the image is not found
     */
    public static ImageIcon getImageRbIcon(String key) {
        ImageIcon icon=null;
        // first check the image cache
        icon = (ImageIcon) imageMap.get(key);
        if (icon==null) {
            // image wasn't found in the cache, find it.
            String imageName=null;
            // Search the resource bundles for the image name that is associated with this key
            for (Iterator i=getInstance().uiImageRbList.iterator(); (imageName==null) && i.hasNext();) {
                ResourceBundle rb = (ResourceBundle)i.next();
                try {
                    imageName = rb.getString(key);
                } catch (MissingResourceException exc) {
                }
            }
            // If no name is found, use the key itself as the name
            if (imageName==null) {
                imageName = key;
            }
            //System.out.println("Locating image: "+imageName);
            // if no path information was provided, then add the default path
            String fullPathName = imageName;
            if (fullPathName.indexOf(File.separatorChar)==-1) {
                fullPathName = imagesDirectory+fullPathName;
            }

            // try locating the image through the class loader
            try {
                //System.out.println("  checking with class loader for image: "+fullPathName);
                URL iconUrl = ConfigResource.class.getResource(fullPathName);
                if (iconUrl!=null) {
                    icon = new ImageIcon(iconUrl);
                    //System.out.println("  found image through classloader: "+iconUrl);
                }
            } catch (MissingResourceException exc) {
            }
            
            // if not found, try locating the image from the web fs
// finish this... re-enable after debugging web fs hang
//             if ((icon==null) && (PathLocater.getDocumentBase()!=null)) {
//                 try {
//                     System.out.println("  checking with documentbase for image: "+imageName);
//                     URL iconUrl = new URL(PathLocater.getDocumentBase(), imageName);
//                     if (iconUrl!=null) {
//                         icon = new ImageIcon(iconUrl);
//                         System.out.println("  found image through web fs: "+iconUrl);
//                     }
//                 } catch (Exception exc) {
//                 }
//             }

            // If we found the image, store it in the cache.
            if (icon!=null) {
                imageMap.put(key, icon);
            }

        }

        if (icon==null) {
            //System.out.println("  image not found.");
            //SystemLog.log("MissingBundleKey", new Serializable[] { DFT_UI_IMAGE_BUNDLE_NAME, key }, new Serializable[] { exc });
        }
        return icon;
    }





    /**
     * Fetches a string from a help text resource bundle. Search the resource bundle stack from the
     * top to the bottom until the message is found. 
     * Note: If the message is not located, then the key value is returned.
     *
     * @param key to use to get text from the resource bundle
     * @return the requested message or the key if the text is missing
     */
    public static String getHelpRbString(String key) {
        String localizedString=null;
        for (Iterator i=getInstance().helpTextRbList.iterator(); (localizedString==null) && i.hasNext();) {
            ResourceBundle rb = (ResourceBundle)i.next();
            try {
                localizedString = rb.getString(key);
            } catch (MissingResourceException exc) {
            }
        }
        if (localizedString==null) {
            localizedString=key;
            //SystemLog.log("MissingBundleKey", new Serializable[] { DFT_HELP_TEXT_BUNDLE_NAME, key }, new Serializable[] { exc });
        }
        return localizedString;
    }



}