var itemComponent = null;

var draggedItem = null;

var startingMouse;

var posnInWindow;

function startDrag(mouse)

{

    posnInWindow = paletteItem.mapToItem(window, 0, 0);

    startingMouse = { x: mouse.x, y: mouse.y }

    loadComponent();

}

//Creation is split into two functions due to an asynchronous wait while

//possible external files are loaded.

function loadComponent() {

    if (itemComponent != null) { // component has been previously loaded

        createItem();

        return;

    }

    itemComponent = Qt.createComponent(paletteItem.componentFile);

    if (itemComponent.status == Component.Loading)  //Depending on the content, it can be ready or error immediately

        component.statusChanged.connect(createItem);

    else    

        createItem();

}

function createItem() {

    if (itemComponent.status == Component.Ready && draggedItem == null) {

        draggedItem = itemComponent.createObject(window);

        draggedItem.image = paletteItem.image;

        draggedItem.x = posnInWindow.x;

        draggedItem.y = posnInWindow.y;

        draggedItem.z = 3;  // make sure created item is above the ground layer

    } else if (itemComponent.status == Component.Error) {

        draggedItem = null;

        console.log("error creating component");

        console.log(itemComponent.errorString());

    }

}

function continueDrag(mouse)

{

    if (draggedItem == null)

        return;

    draggedItem.x = mouse.x + posnInWindow.x - startingMouse.x;

    draggedItem.y = mouse.y + posnInWindow.y - startingMouse.y;

}

function endDrag(mouse)

{

    if (draggedItem == null)

        return;

    if (draggedItem.x + draggedItem.width > toolbox.x) { //Don't drop it in the toolbox

        draggedItem.destroy();

        draggedItem = null;

    } else {

        draggedItem.created = true;

        draggedItem = null;

    }

}