//
//  Bidirectional Textfield Prototype v1.0
//
//  Tries to render a Hebrew or mixed text into a textfield
//  Tries to handle Hebrew input into textfields
//   
//  Author: Mario Klingemann (mario@coma2.com)
//  
//  Usage: 
//         anyTextfield.setBidiText("any testtext")   
//         This is the standard method which is used for multine texts
//
//         anyTextfield.setBidiText("any testtext",true)
//         This forces the text into one line. This is useful for headlines. 
//         Due to the low precision of getTextExtent it can happen that Flash
//         will not fill a line even if there is enough space for a word left
//    
//         anyTextfield.initBidiInput()
//         adds Bidirectionial Text handling for inputfields
//
//         anyTextfield.removeBidiInput()
//         removes Bidirectionial Text handling from inputfields
//
//
//  Shortcomings:
//  - does not render HTML text
//  - precision of .getTextExtend is limited, this can 
//    lead to cases where the layout is not satisfying
//  - does not handle cases of deep nested mixed text
//  - works only withj embedded fonts, otherwise measuring 
//    of text width is not possible and interference with 
//    system routines might occur
//
//  DO NOT USE AUTOFORMAT ON THIS CODE! Due to a bug in Flash this would 
//  destroy the Unicode char string in line 140
//
TextField.prototype.setBidiText = function(text,forceOneLine) {
	var w, s, Hebrew, maxWidth, format, words, currentLine, spac, currentHebrew, currentWord, testLine, lineLength, space, testTempLine, tempLine;
	maxWidth = this._width;
	format = this.getTextFormat();
	paragraphs = text.bidi_cleanWhitespace().split("\n");
	this.text=""
	for (s=0; s<paragraphs.length; s++) {
		words = paragraphs[s].split(" ");
		currentLine ="";
		space = "";
		Hebrew = true;
		for (w=0; w<words.length; w++) {
			currentWord = words[w];
			currentHebrew = currentWord.bidi_isHebrewWord();
			if (currentHebrew) {
				currentWord = currentWord.bidi_revert();
				if (Hebrew) {
					testLine = currentWord+space+currentLine;
				} else {
					testLine = currentWord+space+testTempLine+space+currentLine;
					tempLine = "";
					testTempLine = "";
					Hebrew = true;
				}
			} else {
				testTempLine += space+currentWord;
				if (Hebrew) {
					Hebrew = false;
				}
				testLine = currentLine;
			}
			space = " ";
			if (forceOneLine!=true){
				lineLength = format.getTextExtent(testLine+testTempLine).width;
				if (currentHebrew) {
					if (lineLength>maxWidth) {
						this.replaceSel(currentLine+"\n");
						testLine = "";
						currentLine = currentWord;
					} else {
						currentLine = testLine;
					}
				} else {
					if (lineLength>maxWidth) {
						this.replaceSel(tempLine+space+currentLine+"\n");
						testLine = "";
						if (currentWord.bidi_isEnd() && (!words[w-1].bidi_isHebrewWord() && (words[w+1].bidi_isHebrewWord() || ((words[w+1] == null) && words[w+2].isHebrew())))) {
							testTempLine = currentWord.bidi_flipLastChar();
						} else {
							testTempLine = currentWord;
						}
						tempLine = "";
						currentLine = "";
						testLine = "";
					} else {
						tempLine = testTempLine;
					}
				}
			} else {
				if (currentHebrew) {
					currentLine = testLine;
				} else {
					tempLine = testTempLine;	
				}
			}
		}
		if (currentHebrew) {
			if (currentLine != "") {
				this.replaceSel(currentLine+"\n");
			}
		} else {
			if (testTempLine != "") {
				this.replaceSel(testTempLine+space+currentLine+"\n");
				testTempLine = "";
			}
		}
		tempLine = "";
		testLine = "";
		currentLine = "";
	}
};
String.prototype.bidi_revert = function() {
	return (this.charAt(0).bidi_bracketRevert()+this.substr(1, this.length-2)+this.charAt(this.length-1).bidi_bracketRevert()).split("").reverse().join("");
};

String.prototype.bidi_isHebrewWord = function() {
	
	for (var i = 0; i<this.length; i++) {
		if (!this.bidi_isNeutral(i)) {
			if (this.isHebrewChar(i)) {
				return true;
			} else {
				return false	
			}
		}
	}
	return false;
};

String.prototype.isHebrewChar=function(n){
	if (System.useCodepage) {
		return ('אבגדהוזחטיךכלםמןנסעףפץצקרשת'.indexOf(this.charAt(n))>-1);
	} 
	return ('\u05d0\u05d1\u05d2\u05d3\u05d4\u05d5\u05d6\u05d7\u05d8\u05d9\u05da\u05db\u05dc\u05dd\u05de\u05df\u05e0\u05e1\u05e2\u05e3\u05e4\u05e5\u05e6\u05e7\u05e8\u05e9\u05ea'.indexOf(this.charAt(n))>-1);
	
	
}

String.prototype.bidi_isNeutral = function(n) {
	var chars = "?!{}[]()-=,.*\"' :;";
	if (chars.indexOf(this.charAt(n)) == -1) {
		return 0;
	} else {
		return 1;
	}
};
String.prototype.bidi_isEnd = function() {
	var chars = "?!.:,;";
	if (chars.indexOf(this.charAt(this.length-1)) == -1) {
		return 0;
	} else {
		return 1;
	}
};
String.prototype.bidi_flipLastChar = function() {
	if (this.charAt(0) == " ") {
		return this.charAt(this.length-1)+this.substr(1, this.length-2);
	} else {
		return this.charAt(this.length-1)+this.substr(0, this.length-1);
	}
};
String.prototype.bidi_bracketRevert = function() {
	var s = this.toString();
	switch (s) {
	case "(" :
		return ")";
		break;
	case ")" :
		return "(";
		break;
	case "[" :
		return "]";
		break;
	case "]" :
		return "[";
		break;
	case "}" :
		return "{";
		break;
	case "{" :
		return "}";
		break;
	default :
		return this;
		break;
	}
};
String.prototype.bidi_CleanWhitespace = function() {
	var s = this.split("\r").join("\n");
	while (s.indexOf("  ")>-1) {
		s = s.split("  ").join(" ");
	}
	return s;
};



Textfield.prototype.initBidiInput = function() {
	this.addListener(this);
	this.onChanged = this.bidiProcess;
	this.lastText = this.text;
	this.lastHebrew = false;
	
};
Textfield.prototype.removeBidiInput = function() {
	this.removeListener(this);
	this.onChanged = null;
};

Textfield.prototype.bidiProcess = function() {
	if (this.text == this.lastText) {
		return;
	}
	var insertEnd = Selection.getCaretIndex();
	var newCheck = this.text.substr(0, insertEnd);
	var oldCheck = this.lastText.substr(0, this.lastText.length-(this.text.length-insertEnd));
	var insertStart = 0;
	
	for (var i = 0; i<oldCheck.length; i++) {
		if (this.text.charAt(i) == this.lastText.charAt(i)) {
			insertStart = i+1;
		} else {
			break;
		}
	}
	var dif = this.text.substring(insertStart, insertEnd);
	if (dif.length>1) {
		var words = dif.explode(" ");
		var currentLine, currentWord, currentHebrew, tempLine, testLine;
		var Hebrew = this.lastHebrew;
		var space = "";
		if (words == null) {
			words = [dif];
		}
		
		for (var w=0; w<words.length; w++) {
			currentWord = words[w];
			currentHebrew = currentWord.bidi_isHebrewWord();
			if (currentHebrew) {
				currentWord = currentWord.bidi_revert();
				if (Hebrew) {
					
					currentLine = currentWord+space+currentLine;
				} else {
					currentLine = currentWord+space+tempLine+space+currentLine;
					tempLine = "";
					Hebrew = true;
				}
			} else {
				tempLine += space+currentWord;
				if (Hebrew) {
					Hebrew = false;
				}
			}
			space = " ";
		}
		if (tempLine != "") {
			if (currentLine=="") space=""
			currentLine = tempLine+space+currentLine;
		}
		this.text = this.text.substr(0, insertStart)+currentLine+this.text.substring(insertEnd, this.text.length-1);
		
	}
	
	
	if (dif.bidi_isNeutral(dif.length-1)) {
		if (this.lastHebrew) {
			Selection.setSelection(insertStart, insertStart);
		}
	} else {
		if (dif.isHebrewChar(dif.length-1)) {
			if (this.lastHebrew) {
				Selection.setSelection(insertStart, insertStart);
			} else {
				if (dif.length==1){
					if (this.text.charAt(insertStart-1)==" "){
						this.text = dif +" "+this.text.substr(0, insertStart-1)+this.text.substring(insertEnd, this.text.length-1);	
					} else {
						this.text = dif +this.text.substr(0, insertStart)+this.text.substring(insertEnd, this.text.length-1);						
					}
					
				}
				Selection.setSelection(0, 0);
			}
			this.lastHebrew = true;
		} else {
			this.lastHebrew = false;
		}
	}
	this.lastText = this.text;
};