(function(){

    "use strict"

    
    // Plugin Constructor
    var TagsInput = function(opts){
        this.options = Object.assign(TagsInput.defaults , opts);
        this.init();
    }

    // Initialize the plugin
    TagsInput.prototype.init = function(opts){
        this.options = opts ? Object.assign(this.options, opts) : this.options;

        if(this.initialized)
            this.destroy();
            
        if(!(this.orignal_input = document.getElementById(this.options.selector)) ){
            console.error("tags-input couldn't find an element with the specified ID");
            return this;
        }

        this.arr = [];
        this.wrapper = document.createElement('div');
        this.input = document.createElement('input');
        init(this);
        initEvents(this);

        this.initialized =  true;
        return this;
    }

    // Add Tags
    TagsInput.prototype.addTag = function(string){

        if(this.anyErrors(string))
            return ;

        this.arr.push(string);
        var tagInput = this;

        var tag = document.createElement('span');
        tag.className = this.options.tagClass;
        tag.innerText = string;

        var closeIcon = document.createElement('a');
        closeIcon.innerHTML = '×';
        
        // delete the tag when icon is clicked
        closeIcon.addEventListener('click' , function(e){
            e.preventDefault();
            var tag = this.parentNode;

            for(var i =0 ;i < tagInput.wrapper.childNodes.length ; i++){
                if(tagInput.wrapper.childNodes[i] == tag)
                    tagInput.deleteTag(tag , i);
            }
        })


        tag.appendChild(closeIcon);
        this.wrapper.insertBefore(tag , this.input);
        this.orignal_input.value = this.arr.join(',');

        return this;
    }

    // Delete Tags
    TagsInput.prototype.deleteTag = function(tag , i){
        tag.remove();
        this.arr.splice( i , 1);
        this.orignal_input.value =  this.arr.join(',');
        return this;
    }

    // Make sure input string have no error with the plugin
    TagsInput.prototype.anyErrors = function(string){
        if( this.options.max != null && this.arr.length >= this.options.max ){
            console.log('max tags limit reached');
            return true;
        }
        
        if(!this.options.duplicate && this.arr.indexOf(string) != -1 ){
            console.log('duplicate found " '+string+' " ')
            return true;
        }

        return false;
    }

    // Add tags programmatically 
    TagsInput.prototype.addData = function(array){
        var plugin = this;
        
        array.forEach(function(string){
            plugin.addTag(string);
        })
        return this;
    }

    // Get the Input String
    TagsInput.prototype.getInputString = function(){
        return this.arr.join(',');
    }


    // destroy the plugin
    TagsInput.prototype.destroy = function(){
        this.orignal_input.removeAttribute('hidden');

        delete this.orignal_input;
        var self = this;
        
        Object.keys(this).forEach(function(key){
            if(self[key] instanceof HTMLElement)
                self[key].remove();
            
            if(key != 'options')
                delete self[key];
        });

        this.initialized = false;
    }

    // Private function to initialize the tag input plugin
    function init(tags){
        tags.wrapper.append(tags.input);
        tags.wrapper.classList.add(tags.options.wrapperClass);
        tags.orignal_input.setAttribute('hidden' , 'true');
        tags.orignal_input.parentNode.insertBefore(tags.wrapper , tags.orignal_input);
    }

    // initialize the Events
    function initEvents(tags){
        tags.wrapper.addEventListener('click' ,function(){
            tags.input.focus();           
        });
        

        tags.input.addEventListener('keydown' , function(e){
            var str = tags.input.value.trim(); 

            if( !!(~[9 , 13 , 188].indexOf( e.keyCode ))  )
            {
                e.preventDefault();
                tags.input.value = "";
                if(str != "")
                    tags.addTag(str);
            }

        });
    }


    // Set All the Default Values
    TagsInput.defaults = {
        selector : '',
        wrapperClass : 'tags-input-wrapper',
        tagClass : 'tag',
        max : null,
        duplicate: false
    }

    window.TagsInput = TagsInput;

})();

 var tagInput1 = new TagsInput({
            selector: 'tag-input1',
            duplicate : false,
            max : 10
        });
        tagInput1.addData(['PHP' , 'JavaScript' , 'CSS'])