Oline Hangul Input method by Ho-Seok Ee

ohi.js

/*
 * Author : Ho-Seok Ee <hsee@korea.ac.kr>
 * Release: 2006/07/14
 * Update : 2011/01/22

 Copyright (C) Ho-Seok Ee <hsee@korea.ac.kr>. All rights reserved.
 
  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License as
  published by the Free Software Foundation; either version 2 of
  the License, or (at your option) any later version.
 
  This program 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 General Public License for more details.
 
  The license can be found at http://www.gnu.org/licenses/gpl.txt.
 */

var OHI = function() {
	this._q = Array(0,0,0,0,0,0);
	this.status = document.createElement('a');
	this.kbd = '';
	this.mode = 'Ko';
	this.old_firefox = false;
	var a = navigator.userAgent;
	if (a.indexOf("Firefox") != -1) {
		this.old_firefox = parseFloat(a.substr(a.indexOf("Firefox/")+8)) < 12;
	}
}

OHI.prototype.doubleJamo = function(a,c,d) {
	var i, a=Array( // Double Jamos
		Array(Array(1,7,18,21,24),1,7,18,21,24), // Cho
		Array(Array(39,44,49),Array(31,32,51),Array(35,36,51),51), // Jung
		Array(Array(1,4,9,18,21),Array(1,21),Array(24,30),Array(1,17,18,21,28,29,30),Array(0,21),21))[a]; // Jong
	for (i=a[0].length; c!=a[0][i-1]; i--) if (!i) return i;
	for (a=a[i], i=a.length||1; 1; i--) if (!i || d==a || d==a[i-1]) return i;
}

OHI.prototype.preedit = function(f,m,c) { // Insert
	if (!c && this._q=='0,0,0,0,0,0') return true;
	if (c.length!=6) this._q=Array(0,0,0,0,0,0);
	else {
		var m=m||'0,0,0,0,0,0', i=c[0]+c[1], j=c[2]+c[3], k=c[4]+c[5];
		c=i&&j?0xac00+(i-(i<3?1:i<5?2:i<10?4:i<20?11:12))*588+(j-31)*28+k-(k<8?0:k<19?1:k<25?2:3):0x3130+(i||j||k);
	}
	if (document.selection) { // IE
		var s=document.selection.createRange(), t=s.text;
		if (t && document.selection.clear) document.selection.clear();
		s.text=(m=='0,0,0,0,0,0'||c&&t.length>1?'':t)+String.fromCharCode(c);
		if (!c || !m || s.moveStart('character',-1)) s.select();
	}
	else if (f.selectionEnd+1) {
		if (m!='0,0,0,0,0,0' && f.selectionEnd-f.selectionStart==1) f.selectionStart++;
		var e=document.createEvent('KeyboardEvent');
		if (this.old_firefox && e.initKeyEvent) { // Gecko
			e.initKeyEvent('keypress',0,0,null,0,0,0,0,127,c);
			if (c && f.dispatchEvent(e) && m) f.selectionStart--;
		} else { // Chrome
			var scrollTop = f.scrollTop, scrollLeft = f.scrollLeft, selectionStart = f.selectionStart;
			var endText = f.value.substr(f.selectionEnd,f.value.length);
			f.value = f.value.substr(0,selectionStart)+String.fromCharCode(c);
			var scrollHeight = f.scrollHeight, scrollWidth = f.scrollWidth;
			f.value += endText;
			f.scrollTop = (scrollTop > scrollHeight-f.clientHeight) ? scrollTop : scrollHeight-f.clientHeight;
			f.scrollLeft = (scrollLeft > scrollWidth-f.clientWidth) ? scrollLeft : scrollWidth-f.clientWidth;
			f.setSelectionRange(m?selectionStart:selectionStart+1,selectionStart+1);
		}
	}
}

OHI.prototype.Hangul2 = function(f,c) { // 2-Bulsik
	if (c<65 || (c-1)%32>25) this.preedit(f,0,c);
	else if ((c=Array(17,48,26,23,7,9,30,39,33,35,31,51,49,44,32,36,18,1,4,21,37,29,24,28,43,27)[c%32-1]
			+(c==79||c==80?2:c==69||c==81||c==82||c==84||c==87?1:0))<31) { // Jaum
		if ((!this._q[5] || !(this._q[0]=-1)) && this._q[2]) this._q[5]=this.doubleJamo(2,this._q[4],c);
		if (!this._q[2] || this._q[0]<0 || this._q[0] && (!this._q[4] || !this._q[5]) && (this._q[4] || c==8 || c==19 || c==25))
			this.preedit(f,(this._q=this._q[1]||this._q[2]||!this.doubleJamo(0,this._q[0],c)?this._q:0),this._q=Array(c,this._q?0:1,0,0,0,0));
		else if (!this._q[0] && (this._q[0]=c) || (this._q[4]=this._q[4]||c)) this.preedit(f,0,this._q);
		if (this._q[5]) this._q[5]=c;
	}
	else { // Moum
		if ((!this._q[3] || this._q[4] || !(this._q[2]=-1)) && !this._q[4]) this._q[3]=this.doubleJamo(1,this._q[2],c);
		if ((this._q[0] && this._q[2]>0 && this._q[4]) && (this._q[5] || !(this._q[5]=this._q[4]) || !(this._q[4]=0))) {
			this.preedit(f,0,Array(this._q[0],this._q[1],this._q[2],this._q[3],this._q[4],0));
			this.preedit(f,this._q,this._q=Array(this._q[5],0,c,0,0,0));
		}
		else if ((!this._q[0] || this._q[2]) && (!this._q[3] || this._q[4]) || this._q[2]<0) this.preedit(f,this._q,this._q=Array(0,0,c,0,0,0));
		else if (this._q[2]=this._q[2]||c) this.preedit(f,0,this._q);
	}
}

OHI.prototype.Hangul3 = function(f,c) { // 3-Bulsik
	c=Array(2,183,24,15,14,8220,120,39,126,8221,43,44,41,46,74,119,30,22,18,78,83,68,73,85,79,52,110,44,62,46,33,10,
		/*A~*/7,63,27,12,5,11,69,48,55,49,50,51,34,45,56,57,29,16,6,13,54,3,28,20,53,26,40,58,60,61,59,42,23,79,
		/*a~*/71,86,72,66,84,96,109,115,93,116,122,113,118,121,21,67,4,70,99,74,9,1,101,17,37,92,47,8251)[c-33];
	if (c>92 && c<123) { // Cho
		this.preedit(f,(this._q=this._q[1]||this._q[2]||!this.doubleJamo(0,this._q[0],c-92)?this._q:0),this._q=Array(c-92,this._q?0:1,0,0,0,0));
	}
	else if (c>65 && c<87) { // Jung
		if (!this._q[3] || !(this._q[2]=-1)) this._q[3]=this.doubleJamo(1,this._q[2],c-35);
		if ((!this._q[0] || this._q[2]) && (!this._q[3] || this._q[4]) || this._q[2]<0) this.preedit(f,this._q,this._q=Array(0,0,c-35,0,0,0));
		else if (this._q[2]=this._q[2]||c-35) this.preedit(f,0,this._q);
	}
	else if (c<31) { // Jong
		if (!this._q[5] || !(this._q[4]=-1)) this._q[5]=this.doubleJamo(2,this._q[4],c);
		if (!this._q[0] || !this._q[2] || this._q[4] && !this._q[5] || this._q[4]<0) this.preedit(f,this._q,this._q=Array(0,0,0,0,c,0));
		else if (this._q[4]=this._q[4]||c) this.preedit(f,0,this._q);
	}
	else this.preedit(f,0,c);
}

OHI.prototype.keypressHandler = function(e) {
	var e=e||window.event, f=e.target||e.srcElement, n=f.nodeName||f.tagName, c=e.which||e.which==0?e.which:e.keyCode;
	var i=0, kbd=this.kbd, swaped=Array();
	if (kbd=='QWERTZ') swaped=Array(89,90,90,89,121,122,122,121);
	if (kbd=='AZERTY') swaped=Array(65,81,81,65,87,90,90,87,97,113,113,97,119,122,122,119,77,58,109,59,44,109,58,46,59,44);
	if (f.type=='text' && n=='INPUT' || n=='TEXTAREA') {
		if ((c==10 || c==13 || c==32) && this.preedit(f,0,0) && (e.ctrlKey || e.shiftKey)) { // Toggle
			if ((c==10 || c==13) && e.ctrlKey) this.changeMode('KBD');
			else this.changeMode((e.ctrlKey?'Ko':'K3')+(kbd ? ':'+kbd:''));
			if (e.preventDefault) e.preventDefault();
			return false;
		}
		if (this.mode!='En' && c>32 && c<127 && e.keyCode<127 && !e.altKey && !e.ctrlKey) {
			if (c>64 && c<91 && !e.shiftKey) c+=32;
			if (c>96 && c<123 && e.shiftKey) c-=32;
			if (document.selection && document.selection.createRange().text.length!=1) this._q=Array(0,0,0,0,0,0);
			if (f.selectionEnd+1 && f.selectionEnd-f.selectionStart!=1) this._q=Array(0,0,0,0,0,0);
			while (swaped[i] && swaped[i]!=c) i+=2;
			if (i!=swaped.length) c=swaped[i+1];
			if (this.mode=='Ko') this.Hangul2(f,c);
			if (this.mode=='K3') this.Hangul3(f,c);
			if (e.preventDefault) e.preventDefault();
			return false;
		}
	}
}

OHI.prototype.keydownHandler = function(e) {
	var e=e||window.event, f=e.target||e.srcElement, n=f.nodeName||f.tagName;
	if (f.type=='text' && n=='INPUT' || n=='TEXTAREA') {
		if (e.keyCode==8 && (this._q[1] || this._q[3] || this._q[0] && this._q[2])) { // Backspace
			for (var i=5; !this._q[i];) i--;
			this.preedit(f,this._q[i]=0,this._q);
			if (e.preventDefault) e.preventDefault();
			return false;
		}
		if (e.keyCode==8 && this._q[0]) this._q[0]=0;
		if (e.keyCode!=16 && e.keyCode<47) this.preedit(f,0,0);
		if (e.keyCode==27) f.blur(); // Esc
	}
}

OHI.prototype.changeMode = function(m) {
	if (typeof(m)=='string') {
		if (m=='KBD') this.kbd = !this.kbd?'QWERTZ':this.kbd=='QWERTZ'?'AZERTY':'';
		else this.mode = ((m=='En'||m==this.mode)?'En':m.substr(0,2));
		this.status.innerHTML = this.mode + (this.kbd?':'+this.kbd:'');
	}
}

OHI.prototype.init = function(m) {
	var self = this;
	this.timer = {};
	this.changeMode(m);
	if (document.body) {
		if (document.all) {
			this.status.style.position = 'absolute';
			this.status.style.right = -(document.body.scrollLeft||document.documentElement.scrollLeft)+'px';
			this.status.style.bottom = -(document.body.scrollTop||document.documentElement.scrollTop)+'px';
		}
		if (document.body!=this.status.parentNode) {
			if (!this.status.style.position) {
				this.status.style.position = 'fixed';
				this.status.style.right = '0px';
				this.status.style.bottom = '0px';
			}
			this.status.target = '_blank';
			this.status.href = 'http://ohi.kr/';
			this.status.style.fontFamily = 'GulimChe,monospace';
			this.status.style.fontWeight = 'normal';
			this.status.style.color = 'white';
			this.status.style.backgroundColor = 'royalblue';
			this.status.style.fontSize = '10pt';
			this.status.style.lineHeight = '10pt';
			this.status.style.zIndex = '255';
			document.body.appendChild(this.status);
			if (document.addEventListener) {
				document.addEventListener('keypress', function(e) { return self.keypressHandler(e); }, true);
				document.addEventListener('keydown', function(e) { return self.keydownHandler(e); }, true);
			} else {
				document.onkeypress = function(e) { return self.keypressHandler(e); };
				document.onkeydown = function(e) { return self.keydownHandler(e); };
			}
			var scripts = document.getElementsByTagName('script');
			var src;
			for (j=0; j<scripts.length; j++) {
				src = scripts[j].src;
				if (src.match(/ohi.js$/)) break;
			}
			for (var i=0; i<window.frames.length; i++) {
				var scr = document.createElement('script');
				scr.type= 'text/javascript';
				scr.src = src;
				if (typeof(window.frames[i].document)!='unknown') window.frames[i].document.body.appendChild(scr);
			}
		}
	}
	else {
		if (this.timer) {
			clearTimeout(this.timer);
			this.timer = setTimeout(function() { self.init(m); },100);
		}
	}
}

var ohi = new OHI();
ohi.init('En');