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var taskInput = document.getElementById("new-task"); // new-task
var addButton = document.getElementsByTagName("button")[0]; //first button
var incompleteTasksHolder = document.getElementById("incomplete-tasks"); //ul #incomplete-tasks
var completeTasksHolder = document.getElementById("complete-tasks"); // ul #complete-tasks


//New-task list item
var createNewTaskElement = function(taskString){
  var listItem = document.createElement("li");

  //input (checkbox)
  var checkbox = document.createElement("input");//checkbox
    // label
  var label = document.createElement("label"); // label
    // input (text)
  var editInput = document.createElement("label"); // label
    // button.edit
  var editButton = document.createElement("button"); // button
    //button.delete
  var deleteButton = document.createElement("button"); // button
    //Each element, needs modifying 

    // Each element needs appending
  listItem.appendChild(checkbox);
  listItem.appendChild(label);
  listItem.appendChild(editInput);
  listItem.appendChild(editButton);
  listItem.appendChild(deleteButton);

  return listItem;
}
// add new task
var addTask = function(){
  console.log("add task...");

  //create a new list item with the text from #new-task:
  var listItem = createNewTaskElement("Some new Task");

  // Append listItem to incompleteTaskHolder
  incompleteTasksHolder.appendChild(listItem);
;
}


// edit existing task
var editTask = function(){
  console.log("edit task...");
  // when the dit button is pressed:
    //if the class of the parent is .edit-mode
        //Switch from .edit-mode
        // label text become the input's value
    // elese
      //switch to .editMode
      //input value becomes the labels text

    //toggle .editMode on the parent
}

// delete an existing task
var deleteTask = function() {
  console.log("delete task...");
  //when the delet button is pressed
      // remove parent list itemfrom the ul

}

// mark a task as complete
var taskComplete = function() {
   console.log("task complete...");
   //when the checkbox is checked
    //append the task list item to the #completed-tasks
}

// mark a task as incomplete
var taskIncomplete = function() {
  console.log("task incomplete ...");
  //when the checkbox is unchecked
  //append this task to list item to the #incomplete-tasks
}



var bindTaskEvents = function( taskListItem, checkboxEventHandler) {
  console.log("bind list item...");
  // select list items's children
  var checkbox = taskListItem.querySelector("input[type=checkbox]");
  var editButton = taskListItem.querySelector("button.edit");
  var deleteButton = taskListItem.querySelector("button.delete");

  //bind the editTask to edit button
  editButton.onclick = editTask;

  //bind the delete task to the delete button
  deleteButton.onclick = deleteTask;

    //bind taskComplete to checkbox
  checkbox.onchange = checkboxEventHandler;
}


// Set the click handler to the addTask function
addButton.onclick = addTask;


// cycle over the incompletetaskholder ul list items
  // for each list item
for(var i=0; 1 < incompleteTasksHolder.children.length; i++){
  // bind events to listItems Children (taskCompleted)
  bindTaskEvents(incompleteTasksHolder.children[i], taskComplete);
}



// cycle over the completetaskholder ul list items
  // for each list item
  for(var i=0; 1 < completeTasksHolder.children.length; i++){
  // bind events to listItems Children (taskCompleted)
  bindTaskEvents(completeTaskHolder.children[i], taskIncomplete);
}