S70 6강 - 기존 todo

var todo = (function(){
    var tasks = [];

    var addTask = (function(){
        var id = 0;
        return function(title){
            var result = id;
            tasks.push({id: id++, title: title, state: STATE.PROGRESS()});
            render();
            return result;
        }
    })();

    var removeTask = function(id){
        var isRemoved = false;
        for(var i =0; i< tasks.length; i++){
            if(tasks[i].id === id){
                tasks.splice(i,1);
                isRemoved = true;
                break;
            }
        }
        render();
    };

    var changeState = function(id, state){

        var ID = false, STATE;
        for(var i = 0; i < tasks.length; i++){
            if(tasks[i].id === id){
                ID = id;
                break;
            }
        }
        if(ID === false) {
            warning('changeState : invalid id - ' + id);
            return;
        }
        STATE = state;

        for(var i = 0; i < tasks.length; i++){
            if(tasks[i].id === ID){
                tasks[i].state = STATE;
                break;
            }
        }
        render();
    };
    
    var target;
    var render = function(){ target.render(Object.assign(tasks)); };

    return{
        setRenderer: function(renderer){
            if (!(renderer instanceof Renderer)) return ;
            target = renderer;
            target.init(todo);
        },
        add:addTask,
        remove:removeTask,
        toggle:function(id){
            for(var i = 0; i<tasks.length;i++){
                if(tasks[i].id === id){
                    if(tasks[i].state === STATE.PROGRESS()) changeState(id, STATE.COMPLETE());
                    else changeState(id, STATE.PROGRESS());
                    break;
                }
            }
        }
    }
})();