var i, j, formchecker = {
	result:null, objects:[], object:null, nodeEl:null, errorMessage:"", foundError:false, fieldName:"", formValid:false,
	init:function(form, args){
		args = args==undefined?{}:args;
		form.submit(function(){
			formchecker.result = formchecker.test(this, args.scroll!=undefined?args.scroll:true);
			this.formValid = formchecker.result;
			if(args.onError!=undefined && !this.formValid){
				args.onError(this);
			}
			if(args.onValid!=undefined && this.formValid){
				this.formValid = args.onValid({target:this});
				this.formValid = this.formValid==true||this.formValid==false?this.formValid:true;
			}
			return this.formValid;
		});
	},
	test:function(form, scroll){
		var error;
		this.objects = $(form).find("input,select,textarea");
		this.foundError = false;
		for(i=0; i<this.objects.length; i++){
			this.object = this.objects[i];
			this.object.onfocus = function(){
				formchecker.hideError(this);
			};
			error = !this.checkInput(this.object);
			if(this.foundError==false && error){
				this.foundError = true;
			}
		}
		if(this.foundError){
			var errorItem = $(".formchecker-error");
			if(errorItem.length>0 && scroll){
				errorItem = errorItem[0];
				$("html,body").animate({scrollTop:$(errorItem.parentNode).find("input, textarea, select").offset().top - 10});
			}
		}
		return this.foundError==false;
	},
	filters:{
		length:function(data, len){
			return data.trim().length>=len;
		},
		number:function(num){
			return !isNaN(Number(num)) && num!="";
		},
		e_mail:function(addr){
			return (/^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/).test(addr);
		},
		evalFunction:function(func, object){
			return eval(func + "(object);") == true;
		},
		checkFormat:function(name, list){
			return list!="" && new RegExp("\\.("+list.replace(/\,/g, "|")+")$").test(name);
		}
	},
	hideError:function(obj){
		this.nodeEl = obj.parentNode.getElementsByClassName("error")[0];
		if(this.nodeEl!=undefined){
			this.nodeEl.parentNode.removeChild(this.nodeEl);
		}
	},
	showError:function(obj, message){
		this.nodeEl = Array.prototype.slice.call(obj.parentNode.getElementsByClassName("error")).filter(function(htEl){
			return htEl.errObj==obj;
		});
		this.nodeEl = this.nodeEl[0];
		if(message==""){
			this.nodeEl!=undefined?this.nodeEl.parentNode.removeChild(this.nodeEl):0;
		}else{
			if(this.nodeEl==undefined){
				this.nodeEl = document.createElement("div");
				this.nodeEl.className = "error formchecker-error";
				this.nodeEl.style.color = "#f00";
				this.nodeEl.style.textAlign = "left";
				this.nodeEl.style.marginTop = "5px";
				this.nodeEl.errObj = obj;
				obj.parentNode.appendChild(this.nodeEl);
			}
			this.nodeEl.innerHTML = '<span class="arrow"></span>'+message;
		}
	},
	checkInput:function(element){
		var errorMessage = "";
		if(element.dataset.type!=undefined && element.disabled==false){
			this.fieldName = "this";
			if(element.dataset.label!=undefined){
				this.fieldName = element.dataset.label;
			}else if(element.placeholder!=undefined && element.placeholder!=""){
				this.fieldName = element.placeholder.toLowerCase();
			}else if(element.name!=""){
				this.fieldName = element.name.replace(/[^0-9A-Za-z]/gi, " ");
			}
			errorMessage = "";
			if(element.dataset.type=="string"){
				j = element.dataset.minlen!=undefined?element.dataset.minlen:1;
				if(this.filters.length(element.value, j)==false){
					errorMessage = j<=1?"invalid "+this.fieldName+".":this.fieldName+" requires minimum "+j+" letters !";
					this.foundError = true;
				}
			}else if(element.dataset.type=="number"){
				if(element.dataset.allowed!=undefined && element.dataset.allowed!=""){
				 	element.value = element.value.replace(new RegExp(element.dataset.allowed, "gi"), "");
				}
				if(this.filters.number(element.value)==false){
					errorMessage = "invalid " + this.fieldName + ".";
				}else{
					var amtmin = element.dataset.min, amtmax = element.dataset.max, amterr="";
					amterr = !isNaN(Number(element.dataset.min)) && Number(element.value)<Number(element.dataset.min)?"minimum "+element.dataset.min:amterr;
					amterr += !isNaN(Number(element.dataset.max)) && Number(element.value)>Number(element.dataset.max)?(amterr!=""?" and ":"")+"maximum "+element.dataset.max:"";
					errorMessage = (amterr!=""?this.fieldName+" should be ":"")+amterr;
				}
				
			}else if(element.dataset.type=="email") {
				if(this.filters.e_mail(element.value)==false){
					errorMessage = "invalid " + this.fieldName + ".";
				}
				
			}else if(element.dataset.type=="check") {
				if(!element.checked){
					errorMessage = "please check " + this.fieldName + ".";
				}
				
			}else if(element.dataset.type=="func" && element.dataset.func!=undefined) {
				if(this.filters.evalFunction(element.dataset.func, element)==false){
					errorMessage = "invalid " + this.fieldName + ".";
				}
			}else if(element.dataset.type=="files" && element.dataset.extensions!=undefined) {
				if(this.filters.checkFormat(element.value, element.dataset.extensions)==false){
					errorMessage = "invalid " + this.fieldName + ".";
				}
			}
			errorMessage = errorMessage!="" && element.dataset.errormsg!=undefined?element.dataset.errormsg:errorMessage;
			this.showError(element, errorMessage);
		}
		return errorMessage=="";
	}
};
$.fn.formchecker = function(attrs){
	attrs = attrs==undefined?{}:attrs;
	formchecker.init(this, attrs);
	return $(this);
};