/**
 * License Agreement.
 *
 * Rich Faces - Natural Ajax for Java Server Faces (JSF)
 *
 * Copyright (C) 2007 Exadel, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License version 2.1 as published by the Free Software Foundation.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 */

package org.ajax4jsf.javascript;

import java.beans.PropertyDescriptor;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.Array;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;

import javax.faces.FacesException;

import org.apache.commons.beanutils.PropertyUtils;

/**
 * @author shura (latest modification by $Author: alexsmirnov $)
 * @version $Revision: 1.1.2.3 $ $Date: 2007/01/24 13:22:31 $
 * 
 */
public class ScriptUtils {

	/**
	 * This is utility class, don't instantiate.
	 */
	private ScriptUtils() {

	}

	/**
	 * Convert any Java Object to JavaScript representation ( as possible ).
	 * @param obj
	 * @return
	 */
	public static String toScript(Object obj) {
		if (null == obj) {
			return "null";
		} else if (obj instanceof ScriptString) {
			return ((ScriptString) obj).toScript();
		} else if (obj.getClass().isArray()) {
			StringBuilder ret = new StringBuilder("[");
			boolean first = true;
			for (int i = 0; i < Array.getLength(obj); i++) {
				Object element = Array.get(obj, i);
				if (!first) {
					ret.append(',');
				}
				ret.append(toScript(element));
				first = false;
			}
			return ret.append("] ").toString();
		} else if (obj instanceof Collection) {
			// Collections put as JavaScript array.
			
			@SuppressWarnings("unchecked")
			Collection<Object> collection = (Collection<Object>) obj;
			
			StringBuilder ret = new StringBuilder("[");
			boolean first = true;
			for (Iterator<Object> iter = collection.iterator(); iter.hasNext();) {
				Object element = iter.next();
				if (!first) {
					ret.append(',');
				}
				ret.append(toScript(element));
				first = false;
			}
			return ret.append("] ").toString();
		} else if (obj instanceof Map) {
			
			// Maps put as JavaScript hash.
			@SuppressWarnings("unchecked")
			Map<Object, Object> map = (Map<Object, Object>) obj;

			StringBuilder ret = new StringBuilder("{");
			boolean first = true;
			for (Map.Entry<Object, Object> entry : map.entrySet()) {
				if (!first) {
					ret.append(',');
				}
				
				addEncodedString(ret, entry.getKey());
				ret.append(":");
				ret.append(toScript(entry.getValue()));
				first = false;
			}
			return ret.append("} ").toString();
		} else if (obj instanceof Number || obj instanceof Boolean) {
			// numbers and boolean put as-is, without conversion
			return obj.toString();
		} else if (obj instanceof String) {
			// all other put as encoded strings.
			StringBuilder ret = new StringBuilder();
			addEncodedString(ret, obj);
			return ret.toString();
        } else if (obj instanceof Enum) {
            // all other put as encoded strings.
            StringBuilder ret = new StringBuilder();
            addEncodedString(ret, obj);
            return ret.toString();
        } else if (obj.getClass().getName().startsWith("java.sql.")) {
            StringBuilder ret = new StringBuilder("{");
            boolean first = true;
            for (PropertyDescriptor propertyDescriptor : 
                                PropertyUtils.getPropertyDescriptors(obj)) {
                String key = propertyDescriptor.getName();
                if ("class".equals(key)) {
                    continue;
                }
                Object value = null;
                try {
                    value = PropertyUtils.getProperty(obj, key);
                } catch (Exception e) {
                    continue;
                }

                if (!first) {
                    ret.append(',');
                }
                
                addEncodedString(ret, key);
                ret.append(":");
                ret.append(toScript(value));
                
                first = false;
            }
            return ret.append("} ").toString();
        }

		// All other objects threaded as Java Beans.
        try {
            StringBuilder ret = new StringBuilder("{");
            PropertyDescriptor[] propertyDescriptors = PropertyUtils
                    .getPropertyDescriptors(obj);
            boolean first = true;
            for (PropertyDescriptor propertyDescriptor : propertyDescriptors) {
                String key = propertyDescriptor.getName();
                if ("class".equals(key)) {
                    continue;
                }
                if (!first) {
                    ret.append(',');
                }
                addEncodedString(ret, key);
                ret.append(":");
                ret.append(toScript(PropertyUtils.getProperty(obj, key)));
                first = false;
            }
            return ret.append("} ").toString();
        } catch (Exception e) {
            throw new FacesException(
                    "Error in conversion Java Object to JavaScript", e);
        }
	}

	public static void addEncodedString(StringBuilder buff, Object obj) {
		buff.append("'");
		addEncoded(buff, obj);
		buff.append("'");

	}

	public static void addEncoded(StringBuilder buff, Object obj) {
		JSEncoder encoder = new JSEncoder();
		char chars[] = obj.toString().toCharArray();
		for (int i = 0; i < chars.length; i++) {
			char c = chars[i];
			if (!encoder.compile(c)) {
				buff.append(encoder.encode(c));
			} else {
				buff.append(c);
			}
		}
	}

	public static String getValidJavascriptName(String s) {
	
		StringBuffer buf = null;
		for (int i = 0, len = s.length(); i < len; i++) {
			char c = s.charAt(i);
	
			if (Character.isLetterOrDigit(c)||c=='_' ) {
				// allowed char
				if (buf != null)
					buf.append(c);
			} else {
				if (buf == null) {
					buf = new StringBuffer(s.length() + 10);
					buf.append(s.substring(0, i));
				}
	
				buf.append('_');
				if (c < 16) {
					// pad single hex digit values with '0' on the left
					buf.append('0');
				}
	
				if (c < 128) {
					// first 128 chars match their byte representation in UTF-8
					buf.append(Integer.toHexString(c).toUpperCase());
				} else {
					byte[] bytes;
					try {
						bytes = Character.toString(c).getBytes("UTF-8");
					} catch (UnsupportedEncodingException e) {
						throw new RuntimeException(e);
					}
	
					for (int j = 0; j < bytes.length; j++) {
						int intVal = bytes[j];
						if (intVal < 0) {
							// intVal will be >= 128
							intVal = 256 + intVal;
						} else if (intVal < 16) {
							// pad single hex digit values with '0' on the left
							buf.append('0');
						}
						buf.append(Integer.toHexString(intVal).toUpperCase());
					}
				}
			}
	
		}
	
		return buf == null ? s : buf.toString();
	}
}
