/**
 * Utilities functions
 * 
 * @author Pierre HUBERT
 */

/**
 * Create a new HTML node
 * 
 * @param {String} nodeType The type of the HTML node
 * @param {HTMLElement} appendTo Optionnal, defines node on which the new node will be applied
 * @return {HTMLElement} The newly created element
 */
function createElem(nodeType, appendTo){
	var newElem = document.createElement(nodeType);

	if(appendTo)
		appendTo.appendChild(newElem);

	//Return result
	return newElem;
}

/**
 * Create a new HTML node (version2)
 * 
 * @param {Object} infos Informations about the HTML node to create
 * @info {String} type The type of the new node
 * @info {HTMLElement} appendTo HTML Element that will receive the new node
 * @info {HTMLElement} insertBefore Insert before specified HTML element
 * @info {HTMLElement} insertAsFirstChild Insert the new HTML Element as the first child of the specified element
 * @info {String} class The class of the new element
 * @info {String} id The ID of the new element
 * @info {String} title The title of the new element
 * @info {String} src The src attribute of the new element
 * @info {String} href href attribute for the src element
 * @info {String} elemType The type attribute of the new element
 * @info {String} value The value of the new element
 * @info {String} placeholder The placeholder of the new element
 * @info {String} innerHTML Specify the html content of the newly created element
 * @return {HTMLElement} The newly created element
 */
function createElem2(infos){

	var newElem = document.createElement(infos.type);

	//Append to a specific element
	if(infos.appendTo)
		infos.appendTo.appendChild(newElem);

	//Append before a specific element
	if(infos.insertBefore)
		infos.insertBefore.parentNode.insertBefore(newElem, infos.insertBefore);
	
	//Append as the first child of an element
	if(infos.insertAsFirstChild){
		//Check if the element as already a child or not
		if(infos.insertAsFirstChild.firstChild)
			infos.insertAsFirstChild.insertBefore(newElem, infos.insertAsFirstChild.firstChild);
		//Else we can just append the newly created element
		else
			infos.insertAsFirstChild.appendChild(newElem);
	}

	//Specify the class of the element
	if(infos.class)
		newElem.className = infos.class;

	//Specify the ID of the element
	if(infos.id)
		newElem.id = infos.id;
	
	//Specify the title of the new element
	if(infos.title)
		newElem.title = infos.title;
	
	//Specify the source of the element
	if(infos.src)
		newElem.src = infos.src;
	if(infos.href)
		newElem.href = infos.href;

	//Specify element type
	if(infos.elemType)
		newElem.type = infos.elemType;

	//Specify element value
	if(infos.value)
		newElem.value = infos.value;

	//Specify element placeholder
	if(infos.placeholder)
		newElem.placeholder = infos.placeholder;

	//Specify node content
	if(infos.innerHTML)
		newElem.innerHTML = infos.innerHTML;

	//Return newly created element
	return newElem;
}

/**
 * Get an HTML element specified by an ID
 * 
 * @param {String} nodeName The ID of the element
 * @return {HTMLElement} The element / False for a failure
 */
function byId(nodeName){
	return document.getElementById(nodeName);
}

/**
 * Remove all nodes of a specified HTML element
 * 
 * @param {HTMLElement} container The container to empty
 * @return {Boolean} True for a success
 */
function emptyElem(container){
	//Get children references
	var children = container.children;

	//Process each child
	while(container.children.length > 0){
		
		//Check if the child has subchild
		if(container.children[0].children)
			emptyElem(container.children[0]); //Remove them first

		//Remove child
		container.children[0].remove();
	}
	
	//Success
	return true;
}

/**
 * Delete all the content of an object
 * 
 * @param {Object} object The object to clear
 * @return {Boolean} True for a success
 */
function clearObject(object){

	//Variable (for loop) is specific to this local scop
	var i = 0;
	
	//Process each node of the object
	for(i in object){
		
		if(!object[i])
			continue;

		//Check if the node is an object
		if(object[i].toString() === "[object Object]"){
			clearObject(object[i]); //Delete object content
		}
		
		//Delete node
		delete object[i];
	}

	//Success
	return true;
}

/**
 * Check a given email address
 * 
 * @param {String} emailAddress The email address to check
 * @return {Boolean} True for a valid email address / false else
 */
function checkMail(emailAddress){
	return (emailAddress.match(/^[a-zA-Z0-9_.]+@[a-zA-Z0-9-]{1,}[.][a-zA-Z]{2,5}$/) === null ? false : true);
}

/**
 * Create a formgroup element
 * 
 * @param {Object} infos Informations about the formgroup element to create
 * * @info {HTMLElement} target The target of the field
 * * @info {String} label The label of the field
 * * @info {String} placeholder The placeholder of the field
 * * @info {Boolean} checked Defines if the fields has to be checked or not (checkbox only)
 * * @info {Boolean} multiple Defines if the fields can accept more than one response
 * * @info {String} type The type of the field
 * @return {HTMLElement} The input 
 */
function createFormGroup(infos){
	//Create formgroup
	var formGroup = createElem("div", infos.target);
	formGroup.className = "form-group";

	//Add label
	var labelElem = createElem("label", formGroup);

	//Treatement differs if it is a checkbox
	if(infos.type == "checkbox"){

		//Create checkbox
		var input = createElem("input", labelElem) ;
		input.type = "checkbox";

		//Check if input has to be checked by default
		if(infos.checked){
			if(infos.checked === true){
				input.checked = "true";
			}
		}

		//Add label value
		var labelValue = createElem("span", labelElem);
		labelValue.innerHTML = " "+infos.label;

		//Enable iCheck
		$(input).iCheck({
			checkboxClass: 'icheckbox_flat-blue',
      		radioClass: 'iradio_flat-blue'
		});
	}
	else if(infos.type == "select2"){
		//In case of select2 element
		//Check for label
		if(infos.label)
			labelElem.innerHTML = infos.label;
		else
			labelElem.remove(); //Remove useless label element
		
		//Create input
		var input = createElem("select", formGroup);
		input.style.width = "100%";
		input.className = "form-control select2";
		if(infos.multiple) //For multiple changes
			input.setAttribute("multiple", "multiple");
		if(infos.placeholder) //Placeholder if required
			input.setAttribute("data-placeholder", infos.placeholder);

	}
	//In case of textarea
	else if(infos.type == "textarea"){
		//Fill label value
		if(infos.label)
			labelElem.innerHTML = infos.label;
		else
			labelElem.remove(); //Remove useless label element
		
		//Create textarea element
		var input = createElem2({
			appendTo: formGroup,
			type: "textarea",
			class: "form-control",
			placeholder: infos.placeholder,
		});

	}
	else {
		//Else continue the function as a normal input type
		labelElem.innerHTML = infos.label;

		//Create input group
		var inputGroup = createElem("div", formGroup);
		inputGroup.className = "input-group";
		inputGroup.style.width = "100%";

		//Create input
		var input = createElem("input", inputGroup);
		input.className = "form-control";
		input.type = infos.type;
		input.placeholder = infos.placeholder;
	}

	//Return input
	return input;
}

/**
 * Check if a string is valid and ready to be sent to be saved
 * 
 * @param {String} value The input string to send
 * @return {Boolean} True if the string is valid, false else
 */
function checkString(value){
	
	//First, check string length
	if(value.length < 3)
		return false; //Lenght invalid

	//Success, the string seems to be valid
	return true;

}

/**
 * Remove HTML carachters : < and >
 * 
 * @param {String} input The string to change
 * @return {String} The updated string
 */
function removeHtmlTags(input){
	
	//Prepare update
	var output = input;
	
	//Replace opening braces
	while(output.includes("<")){
		//Replace an occurence
		output = output.replace("<", "&lt;");
	}

	//Replace closing braces
	while(output.includes(">")){
		//Replace an occurence
		output = output.replace(">", "&gt;");
	}
	
	//Return result
	return output;
}