var consonants = { "ക": "ക", "ഖ": "ഖ", "ഗ": "ഗ", "ഘ": "ഘ", "ങ": "ങ", "ച": "ച", "ഛ": "ഛ", "ജ": "ജ", "ഝ": "ഝ", "ഞ": "ഞ", "ട": "ട", "ഠ": "ഠ", "ഡ": "ഡ", "ഢ": "ഢ", "ണ": "ണ", "ത": "ത", "ഥ": "ഥ", "ദ": "ദ", "ധ": "ധ", "ന": "ന", "പ": "പ", "ഫ": "ഫ", "ബ": "ബ", "ഭ": "ഭ", "മ": "മ", "യ": "യ", "ര": "ര", "ല": "ല", "വ": "വ", "ശ": "ശ", "ഷ": "ഷ", "സ": "സ", "ഹ": "ഹ", "ള": "ള", "ഴ": "ഴ", "റ": "റ", "റ്റ": "റ്റ" };
var chillaksharam = { "ണ്‍": "ണ", "ന്‍": "ന", "ം": "മ", "ര്‍": "ര", "ല്‍": "ല", "ള്‍": "ള", "്\\u200D": "" };

var vowels = '"്a":"","്e":"െ","്i":"ി","്o":"ൊ","്u":"ു","്A":"ാ","്E":"േ","്I":"ീ","്O":"ോ","്U":"ൂ","്Y":"ൈ","െe":"ീ","ൊo":"ൂ","ിi":"ീ","ിe":"ീ","ുu":"ൂ","ുo":"ൂ","്r":"്ര്",';
var roman = '"k":"ക്","ക്h":"ഖ്","g":"ഗ്","ഗ്h":"ഘ്","ന്‍g":"ങ്","c":"ക്\\u200D","ക്\\u200Dh":"ച്","ച്h":"ഛ്","j":"ജ്","ജ്h":"ഝ്","ന്‍j":"ഞ്","ന്‍h":"ഞ്","T":"ട്","ട്h":"ഠ്","D":"ഡ്","ഡ്h":"ഢ്","റ്റ്h":"ത്","ത്h":"ഥ്","d":"ദ്","ദ്h":"ധ്","p":"പ്","പ്h":"ഫ്","f":"ഫ്","b":"ബ്","ബ്h":"ഭ്","y":"യ്","v":"വ്","w":"വ്","z":"ശ്","S":"ശ്","സ്h":"ഷ്","s":"സ്","h":"ഹ്","ശ്h":"ഴ്","x":"ക്ഷ്","R":"റ്","t":"റ്റ്",';
var chill = '"N":"ണ്‍","n":"ന്‍","m":"ം","r":"ര്‍","l":"ല്‍","L":"ള്‍",';
var swaram = '"a":"അ","അa":"ആ","A":"ആ","e":"എ","E":"ഏ","എe":"ഈ","i":"ഇ","ഇi":"ഈ","ഇe":"ഈ","അi":"ഐ","I":"ഐ","o":"ഒ","ഒo":"ഊ","O":"ഓ","അu":"ഔ","ഒu":"ഔ","u":"ഉ","ഉu":"ഊ","U":"ഊ","H":"ഃ","റ്h":"ഋ","ര്‍^":"ഋ","ഋ^":"ൠ","ല്‍^":"ഌ","ഌ^":"ൡ",';
//var numerals = '"1":"൧","2":"൨","3":"൩","4":"൪","5":"൫","6":"൬","7":"൭","8":"൮","9":"൯","0":"൦",';
var numerals = '"1":"1","2":"2","3":"3","4":"4","5":"5","6":"6","7":"7","8":"8","9":"9","0":"0",';
var conjuncts = '"ന്‍t":"ന്റ്","ന്റ്h":"ന്ത്","ന്‍k":"ങ്ക്","ന്‍n":"ന്ന്","ണ്‍N":"ണ്ണ്","ള്‍L":"ള്ള്","ല്‍l":"ല്ല്","ംm":"മ്മ്","ന്‍m":"ന്മ്","ന്ന്g":"ങ്ങ്","ന്‍d":"ന്ദ്","ണ്‍m":"ണ്മ്","ല്‍p":"ല്പ്","ംp":"മ്പ്","റ്റ്t":"ട്ട്","ന്‍T":"ണ്ട്","ണ്‍T":"ണ്ട്","്ര്^":"ൃ","ന്‍c":"ന്‍\\u200D","ന്‍\\u200Dh":"ഞ്ച്","ണ്‍D":"ണ്ഡ്",';
var others = '"്L":"്ല്","~":"്\\u200C","്~":"്\\u200C","\\u200C~":"\\u200C","ം~":"മ്","ക്\\u200Dc":"ക്ക്\\u200D","ക്ക്\\u200Dh":"ച്ച്","q":"ക്യൂ",';
var caps = '"B":"ബ്ബ്","C":"ക്ക്\\u200D","F":"ഫ്","G":"ഗ്ഗ്","J":"ജ്ജ്","K":"ക്ക്","M":"മ്മ്","P":"പ്പ്","Q":"ക്യൂ","V":"വ്വ്","W":"വ്വ്","X":"ക്ഷ്","Y":"യ്യ്","Z":"ശ്ശ്",';
var ZWNJ = '"_":"\\u200C"';

// for compatibility with bookmarklets
function cyr_translit(src) {
    return to_cyrillic(src);
}

var conversionHash = undefined;
var maxcyrlength = 0;

function getConversionHash() {
    if (conversionHash == undefined) {
        var opr = "{" + vowels + roman + chill + swaram + numerals + conjuncts + caps + others;
        for (var consonant in consonants) {
            opr += '"' + consonant + 'a":"' + consonant + 'ാ",';
            opr += '"' + consonant + 'e":"' + consonant + 'േ",';
            opr += '"' + consonant + 'i":"' + consonant + 'ൈ",';
            opr += '"' + consonant + 'o":"' + consonant + 'ോ",';
            opr += '"' + consonant + 'u":"' + consonant + 'ൗ",';
        }

        for (var chk in chillaksharam) {
            opr += '"' + chk + 'a":"' + chillaksharam[chk] + '",';
            opr += '"' + chk + 'e":"' + chillaksharam[chk] + 'െ",';
            opr += '"' + chk + 'i":"' + chillaksharam[chk] + 'ി",';
            opr += '"' + chk + 'o":"' + chillaksharam[chk] + 'ൊ",';
            opr += '"' + chk + 'u":"' + chillaksharam[chk] + 'ു",';
            opr += '"' + chk + 'A":"' + chillaksharam[chk] + 'ാ",';
            opr += '"' + chk + 'E":"' + chillaksharam[chk] + 'േ",';
            opr += '"' + chk + 'I":"' + chillaksharam[chk] + 'ീ",';
            opr += '"' + chk + 'O":"' + chillaksharam[chk] + 'ോ",';
            opr += '"' + chk + 'U":"' + chillaksharam[chk] + 'ൂ",';
            opr += '"' + chk + 'Y":"' + chillaksharam[chk] + 'ൈ",';
            opr += '"' + chk + 'r":"' + chillaksharam[chk] + '്ര്",';
            opr += '"' + chk + 'y":"' + chillaksharam[chk] + '്യ്",';
            opr += '"' + chk + 'v":"' + chillaksharam[chk] + '്വ്",';
            opr += '"' + chk + 'w":"' + chillaksharam[chk] + '്വ്",';
            opr += '"' + chk + '~":"' + chillaksharam[chk] + '്\\u200C",';
        }

        opr += ZWNJ + "}";
        conversionHash = eval("(" + opr + ")");
        maxcyrlength = 6;
    }

    return conversionHash;
}

function to_cyrillic(src, output, chunks) {
    if (src == undefined || src == "" || src == null)
        return src;
    if (output == undefined)
        output = new String();

    var hash = getConversionHash();

    var location = 0;
	
    while (location < src.length) {
        var len = Math.min(maxcyrlength, src.length - location);
        var arr = undefined;
        var sub;
		
        while (len > 0) {
			
            sub = src.substr(location, len);
			
            arr = hash[sub];
			
			//alert(document.getElementById('k1'));
			
            if (arr != undefined)
                break;
            else
                len--;
        }

        // need this for translit on the fly
        if (chunks != undefined)
            chunks[chunks.length] = sub;

        if (arr == undefined) {
            output += sub;
            location++;
			
        }
        else {
			
            // case analysis
            var newChar = arr;

            if (sub.toLowerCase() == sub.toUpperCase() && arr.length > 1 && arr[1] && (newChar.toUpperCase() != newChar.toLowerCase())) {
			
                // need translit hash to determine if previous character (and possibly the one before it) 
                // were converted and are in upper case

                // set prevDud to true previous is not a translated character or simply a blank
                // set prevCap to true if previous was translated and was upper case

                var prevCh = output.length == 0 ? null : output.substr(output.length - 1, 1);
                var prevDud = !prevCh || !getTranslitString(prevCh);
                var prevCap = (!prevDud && prevCh == prevCh.toUpperCase());

                // sub is caseless but result isn't. case will depend on lookbehind and lookahead
                if (prevDud || !prevCap) {
                    output += newChar.toLowerCase();
                    prevCap = false;
                }
                else {
                    var next = " ";
                    if (location + len < src.length)
                        next = src.substr(location + len, 1);

                    if (next != next.toUpperCase() && next == next.toLowerCase()) {
                        //next is lowercase (and not caseless)
                        output += newChar.toLowerCase();
                    }
                    else if (next == next.toUpperCase() && next != next.toLowerCase()) {
                        // next is uppercase (and not caseless)
                        output += newChar.toUpperCase();
                    }
                    else {
                        // next is caseless. output case determined by the case of output[length - 2]
                        var pprevCh = output.length == 1 ? null : output.substr(output.length - 2, 1);
                        var pprevDud = !pprevCh || !getTranslitString(pprevCh);
                        if (!pprevDud && (pprevCh == pprevCh.toUpperCase())) {
                            //pre-prev is in upper case. output is also uppercase
                            output += newChar.toUpperCase();
                        }
                        else {
                            output += newChar.toLowerCase();
                        }

                    }
                }

            }
            else if ((sub.toLowerCase() == sub.toUpperCase()) && (arr.length < 2 || !arr[1])) {

                // literal treatment of newChar
                output += newChar;

            }
            else if (sub != sub.toLowerCase()) {

                // sub not all-lowercase
                output += newChar.toUpperCase();
            }
            else {

//alert(newChar+"fff");

                // sub is lowercase
                output += newChar.toLowerCase();
            }
            location += len;
        }
    }

    return output;
}



function convertIt(src, converter) {
    var resultbuffer = "";
    for (var i = 0; i < src.length; i++) {
        resultbuffer = converter(resultbuffer + src[i]);
    }
    return converter(resultbuffer);

}



var translitHash = undefined;

function initTranslit() {
    if (translitHash == undefined) {
        translitHash = new Array();

        for (var i = 0; i < conversionHash.length; i++) {
            var ch = conversionHash[i][1];
            // if the translit string is not caseless, convert cyr string to upper case
            // otherwise maintain its case
            if (conversionHash[i][0].toUpperCase() != conversionHash[i][0].toLowerCase())
                ch = ch.toUpperCase();

            if (translitHash[ch] == undefined)
                translitHash[ch] = conversionHash[i][0];
        }
    }
}




//-- translit on-the-fly -- 

function replaceValue(node, value, stepback) {
    if (stepback == undefined)
        stepback = 0;
	
	
	
    if (isExplorer()) {
		
        var range = document.selection.createRange();
        range.moveStart("character", -stepback);
        range.text = value;
        range.collapse(false);
        range.select();
    }
    else {
		
		
        var scrollTop = node.scrollTop;
        var cursorLoc = node.selectionStart;
		//  alert("node=="+ value+" stepback=="+stepback);
        node.value = node.value.substring(0, node.selectionStart - stepback) + value +
                                                node.value.substring(node.selectionEnd, node.value.length);
		
		//alert("node=="+ node+" stepback=="+stepback);
		//document.getElementById('k').value=node.value;
		//document.getElementById('k1').innerHTML=node.value;
    
	 	node.scrollTop = scrollTop;
        node.selectionStart = cursorLoc + value.length - stepback;
        node.selectionEnd = cursorLoc + value.length - stepback;
    }
}


// compare positions
function positionIsEqual(other) {
    if (isExplorer())
        return this.position.isEqual(other.position);
    else
        return this.position == other.position;

}

function Position(node) {
    if (node.selectionStart != undefined)
        this.position = node.selectionStart;
    else if (document.selection && document.selection.createRange())
        this.position = document.selection.createRange();

    this.isEqual = positionIsEqual;
}

function resetState() {
    this.position = new Position(this.node);
    this.transBuffer = "";
    this.cyrBuffer = "";
}

function StateObject(node) {
    this.node = node;
    this.reset = resetState;
    this.cyrBuffer = "";
    this.transBuffer = "";
    this.position = new Position(node);
}


var stateHash = new Array();

function isExplorer() {
    return (document.selection != undefined && document.selection.createRange().isEqual != undefined);
}

function pressedKey(event) {
    if (isExplorer())
        return event.keyCode;
    else
        return event.which;
}

function transliterateKey(event) {
  // alert(event.charCode);
    if ((event.keyCode == 255 && event.charCode > 0) || event.keyCode == 8) {
    return;
    }
    

    if (event == undefined)
        event = window.event;

    var node = null;

    if (event.target) {
        node = event.target;
    }
    else if (event.srcElement) {
        node = event.srcElement;
    }


    // initialize state
    var state = stateHash[node];
    if (state == null) {
        state = new StateObject(node);
        stateHash[node] = state;
    }
    if ((pressedKey(event) > 20) && !event.ctrlKey && !event.altKey && !event.metaKey) {
	
        var c = String.fromCharCode(pressedKey(event));
		//alert(state)
        // process input
        var result = process_translit(state, c);
       // alert(result.out);
	  
		// finish up
        if (c != result.out || result.replace != 0) {
           //alert(c);
		   if (isExplorer())
                event.returnValue = false;
            else
                event.preventDefault();
			//document.getElementById('k1').innerHTML=result.out;
            replaceValue(node, result.out, result.replace);

            state.position = new Position(node);

        }
    }

}

function TranslitResult() {
    this.out = "";
    this.replace = 0;
}

function process_translit(state, c) {
    // reset state if position changed
  // alert(state.node);
   if (!state.position.isEqual(new Position(state.node)))
        state.reset();

    var result = new TranslitResult();
	
    // initial backbuffer. Add to it as characters are converted
    var backbuffer = getBackBuffer(state.node, state.cyrBuffer.length, 2);
    var chunks = new Array();

    state.transBuffer = state.transBuffer + c
	
    var str = to_cyrillic(state.cyrBuffer + c, backbuffer, chunks);
	
    // remove backbuffer from output
    str = str.substr(backbuffer.length);
    result.out = str;
	
    /* str is now left alone - it has the output matching contents of chunks and 
    will be used to reinitialize backbuffers, along with chunks and state.transBuffer
    */

    // get the difference between state.cyrBuffer and output
    for (var i = 0; i < Math.min(state.cyrBuffer.length, result.out.length); i++) {
        if (state.cyrBuffer.substr(i, 1) != result.out.substr(i, 1)) {
            result.replace = state.cyrBuffer.length - i;
            result.out = result.out.substr(i);
            break;
        }
    }
	//alert(state.cyrBuffer);
    if (result.replace == 0) {
        if (result.out.length < state.cyrBuffer.length)
            result.replace = state.cyrBuffer.length - result.out.length;
        result.out = result.out.substr(Math.min(state.cyrBuffer.length, result.out.length));

         // result.out+="\u0008"

    }
//alert(chunks.length);
    // update state: backbuffer, bufferArray
    if (chunks.length > 0 && chunks[chunks.length - 1] == result.out.substr(result.out.length - 1)) {
        // no convertion took place, reset state
        state.reset();
    }
    else {
        while (state.transBuffer.length > maxcyrlength) {
            state.transBuffer = state.transBuffer.substr(chunks[0].length);
            chunks.shift();
            str = str.substr(1);
        }
        state.cyrBuffer = str;
    }
    return result;
}

function getBackBuffer(node, offset, count) {

   //alert(node);
   //alert(offset)
   if (isExplorer()) { //.tagName.toUpperCase() == "EDITOR") {

        var range = document.selection.createRange();
        range.moveStart("character", -offset);
        var result = range.text.substr(-count);
        if (!result)
            result = "";

        return result;

    } else {
        return node.value.substring(0, node.selectionStart - offset).substr(-count);
    }
}

// need this for bookmarklets
function getSelectedNode() {
    if (document.activeElement)
        return document.activeElement;
    else
        if (window.getSelection && window.getSelection() && window.getSelection().rangeCount > 0) {
        var range = window.getSelection().getRangeAt(0);
        if (range.startContainer && range.startContainer.childNodes && range.startContainer.childNodes.length > range.startOffset)
            return range.startContainer.childNodes[range.startOffset]
    }
    return null;
}

function toggleCyrMode() {
    var node = getSelectedNode();
    if (node) {
        if (stateHash[node]) {
            if (removeKeyEventListener(node))
                delete stateHash[node];
        }
        else {
            if (addKeyEventListener(node))
                stateHash[node] = new StateObject(node);
        }
    }
}

function addKeyEventListener(node) {
    if (node.addEventListener)
        node.addEventListener("keypress", transliterateKey, false);
    else if (node.attachEvent)
        node.attachEvent("onkeypress", transliterateKey);
    else return false;
    return true;
}
function removeKeyEventListener(node) {
    if (node.removeEventListener)
        node.removeEventListener("keypress", transliterateKey, false);
    else if (node.detachEvent)
        node.detachEvent("onkeypress", transliterateKey);
    else return false;
    return true;
}

function getSelectedText() {
    if (isExplorer()) {
        return document.selection.createRange().text;
    }
    else {
        var node = getSelectedNode();
        if (node && node.value && node.selectionStart != undefined && node.selectionEnd != undefined)
            return node.value.substring(node.selectionStart, node.selectionEnd);
    }
    return "";
}