dojo.provide("dojox.charting.scaler.common");

(function(){
	var eq = function(/*Number*/ a, /*Number*/ b){
		// summary: compare two FP numbers for equality
		return Math.abs(a - b) <= 1e-6 * (Math.abs(a) + Math.abs(b));	// Boolean
	};
	
	dojo.mixin(dojox.charting.scaler.common, {
		findString: function(/*String*/ val, /*Array*/ text){
			val = val.toLowerCase();
			for(var i = 0; i < text.length; ++i){
				if(val == text[i]){ return true; }
			}
			return false;
		},
		getNumericLabel: function(/*Number*/ number, /*Number*/ precision, /*Object*/ kwArgs){
			var def = kwArgs.fixed ? 
						number.toFixed(precision < 0 ? -precision : 0) : 
						number.toString();
			if(kwArgs.labelFunc){
				var r = kwArgs.labelFunc(def, number, precision);
				if(r){ return r; }
				// else fall through to the regular labels search
			}
			if(kwArgs.labels){
				// classic binary search
				var l = kwArgs.labels, lo = 0, hi = l.length;
				while(lo < hi){
					var mid = Math.floor((lo + hi) / 2), val = l[mid].value;
					if(val < number){
						lo = mid + 1;
					}else{
						hi = mid;
					}
				}
				// lets take into account FP errors
				if(lo < l.length && eq(l[lo].value, number)){
					return l[lo].text;
				}
				--lo;
				if(lo >= 0 && lo < l.length && eq(l[lo].value, number)){
					return l[lo].text;
				}
				lo += 2;
				if(lo < l.length && eq(l[lo].value, number)){
					return l[lo].text;
				}
				// otherwise we will produce a number
			}
			return def;
		}
	});
})();
