/*
richTextarea {
	methodes {
		constructeur : crée l'objet
		addToHistory : ajoute la valeur courante du champ à l'historique
		historyNext : va à la prochaine valeur dans l'historique relativement à la courante.
		historyBack ; va à la precedente valeur relativement à la courante.
		insert(str) : insere la chaine str à la position du curseur ou à la fin de la selection
		checkKeysAction : verifie si une action a été definie pour la combinaison de touche.
		addShortKey(ctrl, alt, shift, key) : ajoute un raccourci clavier ou le remplaçe si existant ;)
	}
	
	proprietes {
		scrollPos : position du scroll à backup avant la perte du focus
		cursorStartPos : position de debut de selection ou curseur à backup avant la perte du focus
		cursorEndPos : position de fin de selection ou curseur à backup avant la perte du focus
		history : tableau de chaine, historique des valeurs successive du textarea
		cursorHistory : tableau d'entiers, historique des positions successive du curseur
		scrollHistory : tableau d'entiers, historique des positions successive du scroll
		currentInHistory : position actuelle au sein de l'historique
		keysAction : tableau de touche de raccourcis. Il est de la forme : 
				keysAction[ctrlKey][altKey][shiftKey][keyCode] = functtion {};
	}
	
	evenements {
		onvaluechange : evenement declancher à la modification du champs, preferable à onchange.
	}
	
	raccourcis {
		CTRL + Z : annuler derniere action
		CTRL + Y : refaire action
		CTRL + D : dupliquer la ligne ou la selection courante
		TAB : insert une tabulation
		RETURN : saut à la ligne en ajoutant les tabulation de debut de ligne selon le contexte.
		HOME : retour au debut de la ligne, ou au debut apres les indentations.
		CTRL + M : ouvre un prompt et cherche l'expression retournée.
		CTRL + SHIT + M : cherche la prochaine occurence entrée dans le prompt
		CTRL + / : ouvre un prompt et va à la ligne indiquee.
		ALT + P : indique la ligne.
	}
}
*/

/*************************************************************************************************/
/* Modification de l'objet window pour ne pas provoquer de conflits entre les raccourcis clavier */
/*************************************************************************************************/
/*
window.keysAction = new Array();
var wkA = window.keysAction;
for(var i = 0; i < 2; i++) {
	wkA[i] = new Array();
	for(var j = 0; j < 2; j++) {
		wkA[i][j] = new Array();
		for(var k = 0; k < 2; k++) {
			wkA[i][j][k] = new Array(0);
		}
	}
}

window.checkKeysAction = function (e) {
		
	var ctrl = 0;
	var alt = 0;
	var shift = 0;
	var keyCode = 0;
	var kA = this.keysAction;
	if (e.ctrlKey) var ctrl = 1;
	if (e.altKey) var alt = 1;
	if (e.shiftKey) var shift = 1;
	if (e.keyCode) var keyCode = e.keyCode;
	if (	!kA || 
		!kA[ctrl] || 
		!kA[ctrl][alt] || 
		!kA[ctrl][alt][shift] || 
		!kA[ctrl][alt][shift][keyCode]
	) {
		return true;
	} else {
		e.preventDefault();
		e.returnValue = false;
		return false;
	}
};


window.addEventListener('keydown', window.checkKeysAction, true);
*/
/*****************************************************/
/* Fonction de création des instance de richTextarea */
/*****************************************************/

function richTextarea (span) {
	
	
	/* Creation de l'element DOM */
	
	var rTa = document.createElement('textarea');
	
	
	/**************************************/
	/* definition des nouvelle proprietes */
	/**************************************/
	
	rTa.scrollPos = 0;
	rTa.cursorStartPos = 0;
	rTa.cursorEndPos = 0;
	rTa.history = new Array();
	rTa.scrollHistory = new Array();
	rTa.cursorHistory = new Array();
	rTa.currentInHistory = 0;
	rTa.keysAction = new Array();
	rTa.lookForMatches = new Array();
	rTa.lookForPos = 0;
	rTa.lookForCursorPos = 0;
	rTa.lookForExp = '';
	
	
	/********************************************/
	/* declaration de l'evenement onvaluechange */
	/********************************************/
	
	rTa.onvaluechange = null;
	
	
	/************************************************************************/
	/* affectation de la structure "à la xPath" pour les raccourcis clavier */
	/************************************************************************/
	
	var kA = rTa.keysAction;
	for(var i = 0; i < 2; i++) {
		kA[i] = new Array();
		for(var j = 0; j < 2; j++) {
			kA[i][j] = new Array();
			for(var k = 0; k < 2; k++) {
				kA[i][j][k] = new Array(0);
			}
		}
	}
	
	
	/******************************************/
	/* initialisation des ctrl + z / ctrl + y */
	/******************************************/
	
	rTa.history[0] = '';
	rTa.scrollHistory[0] = 0;
	rTa.cursorHistory[0] = 0;
	
	
	/****************************/
	/* affectation des methodes */
	/****************************/
	
	/* historique */
	
	rTa.addToHistory = function () {
		
		if (this.history[this.currentInHistory] == this.value) return false;
		this.currentInHistory++;
		var cI = this.currentInHistory;
		while ( cI < this.history.length - 1 ) this.history.pop();
		this.history[cI] = this.value;
		this.cursorHistory[cI] = this.selectionStart;
		this.scrollHistory[cI] = this.scrollTop;
		return true;
	};
	
	rTa.historyNext = function () {
		
		if ( this.currentInHistory < (this.history.length - 1) ) this.currentInHistory++;
		var cI = this.currentInHistory;
		var sR = this.cursorHistory[cI];
		this.value = this.history[cI];
		this.scrollTop = this.scrollHistory[cI];
		this.setSelectionRange(sR, sR);
		return true;
	};
	
	rTa.historyBack = function () {
		if ( this.currentInHistory > 0 ) this.currentInHistory--;
		var cI = this.currentInHistory;
		var sR = this.cursorHistory[cI];
		this.value = this.history[cI];
		this.scrollTop = this.scrollHistory[cI];
		this.setSelectionRange(sR, sR);
		return true;
	};
	
	
	/* insertion dans le champ */
	
	rTa.insert = function (str, pos) {

		var start = pos?pos:this.selectionStart;
		var end = pos?pos:this.selectionEnd;
		var scrollPos = this.scrollTop;
		var lg = str.length;
		
		this.value = this.value.substring(0, end) + str + this.value.substring(end);
		
		this.setSelectionRange(start + lg, end + lg);
		this.addToHistory();
		this.scrollTop = scrollPos;
		
		this.focus();
		
		return true;
	};
	
	rTa.replace = function (str, near, next) {
		
		var start = near || this.selectionStart;
		var end = next || this.selectionEnd;
		var scrollPos = this.scrollTop;
		
		this.value = this.value.substring(0, start) + str + this.value.substring(end);
		this.setSelectionRange(start, start + str.length);
		this.addToHistory();
		this.scrollTop = scrollPos;
	}
	
	/**** BEGIN WOP ****/
	/*
	rTa.inserto = function (str, pos) {
		
		var start = pos || this.selectionStart;
		var trueStart = this.selectionStart;
		var end = this.selectionEnd;
		var scrollPos = this.scrollTop;
		
		this.value = this.value.substring(0, start) + str + this.value.substring(start);
		
		this.setSelectionRange(trueStart, end);
		this.addToHistory();
		this.scrollTop = scrollPos;
		
		return true;
	}
	*/
	
	/**** END WOP ****/
	
	/* Execute la fonction liée à un raccourcis clavier */
	
	rTa.checkKeysAction = function (e) {
		
		var ctrl = 0;
		var alt = 0;
		var shift = 0;
		var keyCode = 0;
		var kA = this.keysAction;
		if (e.ctrlKey) var ctrl = 1;
		if (e.altKey) var alt = 1;
		if (e.shiftKey) var shift = 1;
		if (e.keyCode) var keyCode = e.keyCode;
		
		if (	!kA || 
			!kA[ctrl] || 
			!kA[ctrl][alt] || 
			!kA[ctrl][alt][shift] || 
			!kA[ctrl][alt][shift][keyCode]
		) return false;
		e.preventDefault();
		return kA[ctrl][alt][shift][keyCode](e);
	};
	
	
	/* Ajoute un raccourcis clavier */
	
	rTa.addShortKey = function (ctrl, alt, shift, key, action) {
		
		rTa.keysAction[ctrl][alt][shift][key] = action;
		//window.keysAction[ctrl][alt][shift][key] = 1; // Bloque le raccourcis de browser au passage ;)
	};
	
	
	
	/******************************/
	/* affectation des evenements */
	/******************************/
	
	rTa.onblurev = function () {
		
		this.cursorStartPos = this.selectionStart;
		this.cursorEndPos = this.selectionEnd;
	};
	
	rTa.onfocusev = function () {
		
		this.scrollTop = this.scrollPos;
		this.setSelectionRange(this.cursorStartPos, this.cursorEndPos);
	};
	
	rTa.onkeydownev = function (event) {
		
		if (this.value != this.valueBefore) {
			this.addToHistory();
			this.valueBefore = this.value;
		}
		return !this.checkKeysAction(event);
	};
	
	rTa.onkeyupev = function (event) {
		
		if ( this.value != this.valueBefore && !this.historyNavigate ) this.addToHistory();
		if ( this.value != this.valueBefore && this.onvaluechange ) this.onvaluechange(event);
		this.historyNavigate = false;
		this.valueBefore = this.value;
		//span.innerText = this.getPos();
	};
	
	rTa.onwheel = function () {
		
		this.scrollPos = this.scrollTop;
	}
	
	rTa.addEventListener('blur', rTa.onblurev, false);
	rTa.addEventListener('focus', rTa.onfocusev, false);
	rTa.addEventListener('keydown', rTa.onkeydownev, false);
	rTa.addEventListener('keyup', rTa.onkeyupev, false);
	rTa.addEventListener('scroll', rTa.onwheel, false);
	
	/*******************************************************/
	/* definition des fonction pour les raccourcis de base */	
	/*******************************************************/
	
	rTa.enter = function (e) {	//touche entrer
	
		var lignes = rTa.value.substring(0, rTa.selectionStart).split("\n");
		var ligne = lignes[lignes.length - 1];
		var exp = /^[\t *]*/g;
		var tab = ligne.match(exp);
		return rTa.insert("\n" + tab);
	};
	
	rTa.duplicate = function (e) { 	//touche CTRL + D
		
		var st = rTa.selectionStart;
		var en = rTa.selectionEnd;
		if (st == en) {
			var lignes = rTa.value.substring(0, st).split("\n");
			var et = rTa.value.substring(st).split("\n");
			var endligne = '';
			if (et[0]) endligne = et[0];
			var ligne = endligne + "\n" + lignes[lignes.length - 1];
		} else {
			var ligne = rTa.value.substring(st, en);
		}
		rTa.scrollTop += 20 * ((ligne.match("\n")?ligne.match("\n").length:0.5));
		return rTa.insert(ligne);
	};
	
	
	rTa.undo = function (e) { 		//touche CTRL + Z
		
		return rTa.historyBack();
	};
	
	rTa.redo = function (e) { 		//touche CTRL + Y
		
		return rTa.historyNext();
	};
	
	rTa.tab = function (e) { 		//touche TAB
		
		return rTa.insert("\t");
	};
	
	/**** BEGIN WOP **** /
	
	rTa.tabo = function(e) {
		
		if (rTa.selectionStart == rTa.selectionEnd) return rTa.insert("\t");
		var count = rTa.value.substring(rTa.selectionStart, rTa.selectionEnd).split("\n");
		var ret = true;
		var pos = 0;
		var tot = 0;
		for ( var i = 1; i < count.length - 1; i++) {
			
			pos = rTa.selectionStart + tot;
			alert(pos);
			tot += count[i].length + 1;
			ret = ret && rTa.inserto("\t", pos);
		}
		
		return ret;
	}
	/**/
	
	rTa.taba = function () {
		
		var start = rTa.selectionStart;
		var end = rTa.selectionEnd;
		if (start == end) return rTa.insert("\t");
		return rTa.replace(rTa.value.substring(start, end).replace(/\n/g, "\n\t"));
		
	}
	
	/**** END WOP ****/
	rTa.startPos = function (e) {	// HOME
		
		var sS = rTa.selectionStart;
		var lignes = rTa.value.substring(0, sS).split("\n");
		var endligne = rTa.value.substring(sS).split("\n")[0];
		var ligne = lignes[lignes.length - 1];
		var exp = /^[\t|| ]*/g;
		var nP = 0;
		if (ligne.length == 0) {
			var tmp = endligne.match(exp)?endligne.match(exp)[0].length:0;
			nP = sS + tmp;
		} else {
			nP = sS - ligne.length;
		}
		rTa.setSelectionRange(nP, nP);
		return true;
	}
	
	
	rTa.goTo = function (e) {	// CTRL + / aller à la ligne numreo ...
		
		var line = prompt("Aller à la ligne numéro : ");
		if (!line) return true;
		var z = rTa.value;
		var lines = z.split("\n");
		var k = 0;
		for (var i = 0; i < line - 1; i++) {
			k += lines[i].length + 1;
		}
		a = lines[line - 1].length;
		rTa.scrollTop = rTa.scrollHeight * (line / lines.length) - 100;
		rTa.setSelectionRange(k, k + a);
		return true;
	}
	
	rTa.find = function () {	// CTRL + M cherche la regex ...
		
		rTa.lookForExp = prompt("Rechercher l'expression suivante : ", rTa.lookForExp);
		var expi = new RegExp(rTa.lookForExp, 'g');
		rTa.lookForMatches = rTa.value.match(expi);
		rTa.lookForPos = 0;
		rTa.lookForCursorPos = 0;
		rTa.findNext();
		return true;
	}
	
	rTa.findNext = function () {	// CTRL + SHIFT + M cherche la regex suivante.
		
		if (!rTa.lookForMatches || !rTa.lookForMatches.length) {
			alert('Pas de correspondances trouvées');
			return false;
		}
		if (rTa.lookForPos >= rTa.lookForMatches.length) {
			alert('Fin du document, retour au debut');
			rTa.lookForPos = 0;
			rTa.lookForCursorPos = 0;
		}
		var mt = rTa.lookForMatches[rTa.lookForPos];
		var st = rTa.value.indexOf(mt, rTa.lookForCursorPos);
		var x = rTa.value.substring(0, st).split("\n").length;
		var y = rTa.value.split("\n").length;
		rTa.scrollTop = rTa.scrollHeight * (x / y) - 100;
		rTa.setSelectionRange(st, st + mt.length);
		rTa.lookForCursorPos = st + 1;
		rTa.focus();
		rTa.lookForPos++;
		return true;
	}
	
	rTa.getPos = function () {
		var a = rTa.value.substring(0, rTa.selectionStart).match(/\n/g);
		
		if (!a)
			a = 0;
		else
			a = a.length;
		
		return a;
		
	}
	
	rTa.alertPos = function () {
		
		alert(this.getPos());
		
	}
	
	/********************************/
	/* ajout des raccourcis de base */
	/********************************/
	
	// CTRL ALT SHIFT KeyCode
	
	rTa.addShortKey(1, 1, 0, 90, rTa.undo); 		// CTRL + ALT + Z
	rTa.addShortKey(1, 1, 0, 89, rTa.redo); 		// CTRL + ALT + Y
	rTa.addShortKey(1, 0, 0, 68, rTa.duplicate); 		// CTRL + D
	rTa.addShortKey(0, 0, 0, 9,  rTa.taba);			// TAB
	rTa.addShortKey(0, 0, 0, 13, rTa.enter); 		// RETURN
	rTa.addShortKey(0, 0, 0, 36, rTa.startPos); 		// HOME
/*	rTa.addShortKey(1, 0, 0, 191, rTa.goTo); 		// CTRL + / ou CTRL + : sous windows
	rTa.addShortKey(1, 0, 0, 59, rTa.goTo); 		// CTRL + / ou CTRL + : sous ubunutu kde4 */
	rTa.addShortKey(1, 0, 0, 77, rTa.find); 		// CTRL + M  rechercher
	rTa.addShortKey(1, 0, 1, 77, rTa.findNext); 		// CTRL + SHIFT + M  rechercher suivant
	rTa.addShortKey(1, 1, 0, 80, rTa.alertPos); 		// ALT + P : indique la ligne
	
	return rTa;
}