/*
 * Initializes a new instance of the VietUni class.
 * mode:	Kieu go~ (1=telex, 2=vni, 3=viqr, 4=all, otherwise=off). Default: 4;
 */
function CVietUni(mode) {
	if (document.all || document.getElementById) {
		this.keyModeId = (mode==undefined || mode==null) ? 4 : mode;
		return this;
	}
	alert("Xin loi, trinh duyet web cua ban khong cho phep dung VietTyping.");
	return false;
}
/*
 * Thay doi kieu go~.
 */
CVietUni.prototype.setMethod = function(mode) {
	this.keyModeId = mode;
	if (this.typer) this.typer.keyMode = this.initKeys();
};
CVietUni.prototype.initKeys = function() {
	switch (this.keyModeId) {
	case 1:
		if (!this.telexKeys) this.telexKeys = new CTelexKeys();
		return this.telexKeys;
	case 2:
		if (!this.vniKeys) this.vniKeys = new CVniKeys();
		return this.vniKeys;
	case 3:
		if (!this.viqrKeys) this.viqrKeys = new CViqrKeys();
		return this.viqrKeys;
	case 4:
		if (!this.allKeys) this.allKeys = new CAllKeys();
		return this.allKeys;
	default:
		if (!this.vkOff) this.vkOff = new CVKOff();
		return this.vkOff;
	}
};
/*
 * Cai dat bo go tieng Viet cho 1 textbox / textarea / iframe.
 */
CVietUni.prototype.initTyper = function(obj) {
	if (!obj) return;
	if (!this.typer) {
		this.typer = new CVietTyper();
		this.typer.keyMode = this.initKeys();
	} var othis = this;
	if (obj.attachEvent) obj.attachEvent("onkeypress", function(evt){ return CVietUni.vietTyping(evt, othis, obj); });
	else if (obj.addEventListener) obj.addEventListener("keypress", function(evt){ return CVietUni.vietTyping(evt, othis, obj); }, true);
	else if (obj.onkeypress) obj.onkeypress = function(evt){ return CVietUni.vietTyping(evt, othis, obj); };
};
/*
 * Bat su kien 'onKeyPress' cua 1 textbox / textarea / iframe.
 */
CVietUni.vietTyping = function(evt, vUni, el) {
	if (!vUni || vUni.typer.keyMode.off) return true;
	if (!evt) evt = event;	// fix event
	var c = document.all ? evt.keyCode : (evt.which||evt.charCode);
	if (c < 49 && c != 16 && c != 20) return true;
	// gets current word
	var len, s = vUni.getCurrentWord(el);
	if (s == null || (len=s.length) < 1) return true;
	// bo? da'u tie'ng Viet
	vUni.typer.value = s;
	if (c > 32 && vUni.typer.typing(c)) {
		// co su tang do da`i
		if (((s=vUni.typer.value).length == len+1) && c == s.charCodeAt(len)) {
			// fix replace word length
			vUni.typer.value = s.substr(0, len); len=0;
		}
		vUni.replaceWord(el, vUni.typer.value);
		if (len > 0) {	// no need to disable current key
			if (typeof(evt.cancelBubble)!="undefined") evt.cancelBubble = true;
			if (evt.stopPropagation) { evt.preventDefault(); evt.stopPropagation(); } return false;
		}
	}
	if (evt.cancelBubble) return false; return true;
};
CVietUni.prototype.getCurrentWord = function(el) {
	if (document.selection && !el.createRange) {	// for IE, Opera-textbox
		var caret = (el.selection ? el : el.document).selection.createRange();
		if (caret.text) return null;	// is selected ?
		var caret2;
		try {
			caret2 = caret.duplicate();
			caret2.moveStart("word", -1);
		} catch(e) {
			var backward = -10;
			do {
				caret2 = caret.duplicate();
				caret2.moveStart("character", backward++);
			} while (!caret2.text && backward < 0);
		}
		el.curWord = caret2.duplicate();
		return caret2.text;
	}
	else if (el.setSelectionRange) {	// for Firefox textbox
		var p1 = el.selectionStart, p2 = el.selectionEnd;
		if (p1 != p2) return null;		// is selected ?
		p1 = Math.max(0, p2 - 10);
		el.pos1 = p1; el.pos2 = p2;
		return el.value.substr(p1, p2 - p1);
	}
	else if (window.getSelection) {		// for Firefox, Opera iframe
		var sel = el.defaultView.getSelection();
		var rng = sel.getRangeAt(sel.rangeCount - 1).cloneRange();
		if (rng.toString()) return null; // is selected ?
		// get neareat word
		var p2 = rng.startOffset, nod = rng.endContainer;
		rng.setEnd(nod, p2); rng.setStart(nod, Math.max(0, p2 - 10));
		// store current word
		el.rng = rng; el.node = nod;
		el.pos1 = rng.startOffset; el.pos2 = p2;
		var txt = rng.toString(); rng.setStart(nod, p2);
		return txt;	// restore cursor-position
	}
	else if (typeof(el.value)!="undefined") return el.value;
	else return null;
};
CVietUni.prototype.replaceWord = function(el, newWord) {
	if (document.selection && !el.createRange) {	// for IE, Opera-textbox
		el.curWord.text = newWord;
		el.curWord.collapse(false);
	}
	else if (el.setSelectionRange) {	// for Firefox textbox
		var p1 = el.pos1, p2 = el.pos2, txt = el.value;
		el.value = txt.substr(0, p1) + newWord + txt.substr(p2);
		el.setSelectionRange(p1 + newWord.length, p1 + newWord.length);
	}
	else if (window.getSelection) {		// for Firefox, Opera iframe
		el.rng.setStart(el.node, el.pos1);
		//alert(newWord +':'+ el.pos1 +':'+ el.pos2);
		el.node.replaceData(el.pos1, el.pos2 - el.pos1, newWord);
		// move cursor to the end
		el.rng.setEnd(el.node, el.pos2); el.rng.setStart(el.node, el.pos2);
	}
	else if (typeof(el.value)!="undefined") el.value = newWord;
};

/*---------- VietTyper class ----------*/
function CVietTyper() {
	this.value = "";
	this.charMap = new CVietUniCodeMap();
	this.ctrlChar = '-';
	this.changed = 0;
	return this;
}
CVietTyper.prototype.typing = function(ctrl) {
	//if (this.keyMode.off) return 0;
	this.changed = 0;
	this.ctrlChar = String.fromCharCode(ctrl);
	this.keyMode.getAction(this);
	this.correct();
	return this.changed;
};
CVietTyper.prototype.compose = function(typ) {
	if (!this.value) return;
	var info = this.findCharToChange(typ);
	if (!info || !info[0]) return; var telex;
	if (info[0] == '\\') telex = [1, this.ctrlChar, 1];
	else if (typ > 6) telex = this.charMap.getAEOWD(info[0], typ, info[3]);
	else telex = this.charMap.getDau(info[0], typ);
	if (!(this.changed = telex[0])) return;
	// replace a character at info[1]
	this.value = this.value.substr(0, info[1]) + telex[1] + this.value.substr(info[1] + info[2]);
	if (!telex[2]) this.value += this.ctrlChar;	// spell error
};
CVietTyper.prototype.correct = function() {
	//if (!document.all) return 0;
	var val = this.value;
	if ('nNcC'.indexOf(this.ctrlChar) >= 0) val += this.ctrlChar;
	var er = /[^\x01-\x7f](hn|hc|gn)$/i.exec(val);
	if (er) {
		this.value = val.substr(0, val.length - 2) + er[1].charAt(1) + er[1].charAt(0);
		this.changed = 1;
	} else if (!this.changed) return 0;
	er = /\w([^\x01-\x7f])(\w*)([^\x01-\x7f])\S*$/.exec(this.value);
	if (!er) return 0;
	var i = this.charMap.isVowel(er[1]);
	var ri = (i - 1) % 24 + 1, ci = (i - ri) / 24;
	var i2 = this.charMap.isVowel(er[3]);
	if (!ci || !i2) return 0;
	var ri2 = (i2 - 1) % 24 + 1;
	var nc = this.charMap.charAt(ri) + er[2] + this.charMap.charAt(ci * 24 + ri2);
	this.value = this.value.replace(new RegExp(er[1] + er[2] + er[3], 'g'), nc);
};
CVietTyper.prototype.findCharToChange = function(typ) {
	var lastChars = this.charMap.lastCharsOf(this.value, 5);
	var i = 0, c = lastChars[0][0], chr = 0;
	if (c == '\\') return [c, this.value.length - 1, 1];
	if (typ == 15) while (!(chr = this.charMap.isVD(c))) {
		if ((c < 'A') || (i >= 4) || !(c = lastChars[++i][0])) return null;
	} else while ("cghmnptCGHMNPT".indexOf(c) >= 0) {
		if ((c < 'A') || (i >= 2) || !(c = lastChars[++i][0])) return null;
	}
	c = lastChars[0][0].toLowerCase();
	var pc = lastChars[1][0].toLowerCase();
	var ppc = lastChars[2][0].toLowerCase();
	if (i == 0 && typ != 15) {
		if ((chr = this.charMap.isVowel(lastChars[1][0])) && ("uyoia".indexOf(c) >= 0) && !this.charMap.isUO(pc, c)
			&& !((pc == 'o' && c == 'a') || (pc == 'u' && c == 'y')) && !((ppc == 'q' && pc == 'u') || (ppc == 'g' && pc == 'i')))++i;
		if (c == 'a' && (typ == 9 || typ == 7)) i = 0;
	}
	c = lastChars[i][0];
	if ((i == 0 || chr == 0) && typ != 15) chr = this.charMap.isVowel(c);
	if (!chr) return null;
	var clen = lastChars[i][1], isuo = 0;
	if ((i > 0) && (typ == 7 || typ == 8 || typ == 11)) {
		isuo = this.charMap.isUO(lastChars[i + 1][0], c);
		if (isuo) {
			chr = isuo;
			clen += lastChars[++i][1];
			isuo = 1;
		}
	}
	var pos = this.value.length;
	for (var j = 0; j <= i; j++) pos -= lastChars[j][1];
	return [chr, pos, clen, isuo];
};
/*---------- End of VietTyper class ----------*/

/*---------- VietCharMap class ----------*/
function CVietCharMap() {
	this.vietChars = null;
	this.length = 149;
	this.chrCache = new Array(20);
	this.indCache = new Array(20);
	this.cptr = 0;
	this.caching = function(chr, ind) {
		this.chrCache[this.cptr] = chr;
		this.indCache[this.cptr++] = ind;
		this.cptr %= 20;
	}
	// constants
	this.vmap = [[7, 7, 7, 8, 8, 8, 9, 10, 11, 15], [0, 3, 6, 0, 6, 9, 0, 3, 6, 0], [1, 4, 7, 2, 8, 10, 1, 4, 7, 1]];
	return this;
}
CVietCharMap.prototype.charAt = function(ind) {
	var chrCode = this.vietChars[ind];
	return chrCode ? String.fromCharCode(chrCode) : null;
};
CVietCharMap.prototype.isVowel = function(chr) {
	var i = 0;
	while ((i < 20) && (chr != this.chrCache[i]))++i;
	if (i < 20) return this.indCache[i];
	i = this.length - 5;
	while ((chr != this.charAt(i)) && i)--i;
	this.caching(chr, i);
	return i;
};
CVietCharMap.prototype.isVD = function(chr) {
	var ind = this.length - 5;
	while ((chr != this.charAt(ind)) && (ind < this.length))++ind;
	return (ind < this.length) ? ind: 0;
};
CVietCharMap.prototype.isUO = function(c1, c2) {
	if (!c1 || !c2) return 0;
	var ind1 = this.isVowel(c1);
	var ci = (ind1 - 1) % 12;
	if ((ci != 9) && (ci != 10)) return 0;
	var ind2 = this.isVowel(c2);
	ci = (ind2 - 1) % 12;
	if ((ci != 6) && (ci != 7) && (ci != 8)) return 0;
	return [ind1, ind2];
};
CVietCharMap.prototype.getDau = function(ind, typ) {
	var accented = (ind < 25) ? 0: 1;
	var indI = (ind - 1) % 24 + 1;
	var charSet = (typ == 6) ? 0: typ;
	if ((typ == 6) && !accented) return [0];
	var newInd = charSet * 24 + indI;
	if (newInd == ind) newInd = indI;
	var chr = this.charAt(newInd);
	if (!chr) chr = this.lowerCaseOf(0, newInd);
	return [1, chr, newInd > 24 || typ == 6];
};
CVietCharMap.prototype.getAEOWD = function(ind, typ, isuo) {
	var c = 0, i1 = isuo ? ind[0] : ind;
	var vc1 = (typ == 15) ? (i1 - 1) % 2: (i1 - 1) % 12;
	if (isuo) {
		var base = ind[1] - (ind[1] - 1) % 12;
		if (typ == 7 || typ == 11) c = this.charAt(i1 - vc1 + 9) + this.charAt(base + 7);
		else if (typ == 8) c = this.charAt(i1 - vc1 + 10) + this.charAt(base + 8);
		return [c != 0, c, 1];
	}
	var i = -1, shif = 0, del = 0;
	while (shif == 0 && ++i < this.vmap[0].length) {
		if (this.vmap[0][i] == typ) {
			if (this.vmap[1][i] == vc1) shif = this.vmap[2][i] - vc1;
			else if (this.vmap[2][i] == vc1) shif = this.vmap[1][i] - vc1;
		}
	}
	if (shif == 0) {
		if (typ == 7 && (vc1 == 2 || vc1 == 8)) shif = -1;
		else if ((typ == 9 && vc1 == 2) || (typ == 11 && vc1 == 8)) shif = -1;
		else if (typ == 8 && (vc1 == 1 || vc1 == 7)) shif = 1;
		del = 1;
	} else del = (shif > 0);
	i1 += shif;
	var chr = this.charAt(i1);
	if (i1 < 145) this.caching(chr, i1);
	if (!chr) chr = this.lowerCaseOf(0, i1);
	return [shif != 0, chr, del];
};
CVietCharMap.prototype.lastCharsOf = function(str, len) {
	if (!len) return [str.charAt(str.length - 1), 1];
	var vchars = new Array(len);
	for (var i = 0; i < len; i++) {
		vchars[i] = [str.charAt(str.length - i - 1), 1];
	}
	return vchars;
};
/*---------- End of VietCharMap class ----------*/

/*---------- VietUniCodeMap class ----------*/
function CVietUniCodeMap() {
	var vcmap = new CVietCharMap();
	vcmap.vietChars = new Array("UNICODE", 97, 226, 259, 101, 234, 105, 111, 244, 417, 117, 432, 121, 65, 194, 258, 69, 202, 73, 79, 212, 416, 85, 431,
		89, 225, 7845, 7855, 233, 7871, 237, 243, 7889, 7899, 250, 7913, 253, 193, 7844, 7854, 201, 7870, 205, 211, 7888, 7898, 218, 7912, 221, 224,
		7847, 7857, 232, 7873, 236, 242, 7891, 7901, 249, 7915, 7923, 192, 7846, 7856, 200, 7872, 204, 210, 7890, 7900, 217, 7914, 7922, 7841, 7853,
		7863, 7865, 7879, 7883, 7885, 7897, 7907, 7909, 7921, 7925, 7840, 7852, 7862, 7864, 7878, 7882, 7884, 7896, 7906, 7908, 7920, 7924, 7843, 7849,
		7859, 7867, 7875, 7881, 7887, 7893, 7903, 7911, 7917, 7927, 7842, 7848, 7858, 7866, 7874, 7880, 7886, 7892, 7902, 7910, 7916, 7926, 227, 7851,
		7861, 7869, 7877, 297, 245, 7895, 7905, 361, 7919, 7929, 195, 7850, 7860, 7868, 7876, 296, 213, 7894, 7904, 360, 7918, 7928, 100, 273, 68, 272);
	return vcmap;
}
/*---------- End of VietUniCodeMap class ----------*/

/*---------- VietKeys classes ----------*/
function CVietKeys() {
	this.getAction = function(typer) {
		var i = this.keys.indexOf(typer.ctrlChar.toLowerCase());
		if (i >= 0) typer.compose(this.actions[i]);
	}
	return this;
}
function CVKOff() {
	this.off = true;
	this.getAction = function(typer) {};
	return this;
}

function CTelexKeys() {
	var k = new CVietKeys();
	k.keys = "sfjrxzaeowd";
	k.actions = [1, 2, 3, 4, 5, 6, 9, 10, 11, 8, 15];
	return k;
}
function CVniKeys() {
	var k = new CVietKeys();
	k.keys = "0123456789";
	k.actions = [6, 1, 2, 4, 5, 3, 7, 8, 8, 15];
	return k;
}
function CViqrKeys() {
	var k = new CVietKeys();
	k.keys = "\xB4/'\u2019`.?~-^(*+d";
	k.actions = [1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 15];
	return k;
}
function CAllKeys() {
	var k = new CVietKeys();
	k.keys = "sfjrxzaeowd0123456789\xB4/'`.?~-^(*+d";
	k.actions = [1, 2, 3, 4, 5, 6, 9, 10, 11, 8, 15, 6, 1, 2, 4, 5, 3, 7, 8, 8, 15, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 15];
	return k;
}
/*---------- End of VietKeys classes ----------*/

var VUni = new CVietUni();	// default instance