package ui

import "opslag.de/schobers/geom"

type DragDropEventTarget interface {
	DragEnter(geom.PointF32, []string)
	DragMove(geom.PointF32)
	DragLeave()
	Drop(geom.PointF32, []string)
}

type DragDropProvider interface {
	Register(windowHandle uintptr, target DragDropEventTarget)
}

var DefaultDragDropProvider DragDropProvider = nil

type dragDropEventTarget struct {
	renderer Renderer
	events   []Event
}

func (t *dragDropEventTarget) eventBase() EventBase {
	return EventBase{StampInSeconds: t.renderer.Stamp()}
}

func (t *dragDropEventTarget) pushEvent(e Event) {
	t.events = append(t.events, e)
	t.renderer.Refresh()
}

func (t *dragDropEventTarget) DragEnter(pos geom.PointF32, files []string) {
	t.pushEvent(&DisplayDragEnterEvent{EventBase: t.eventBase(), X: pos.X, Y: pos.Y, Files: files})
}

func (t *dragDropEventTarget) DragMove(pos geom.PointF32) {
	t.pushEvent(&DisplayDragMoveEvent{EventBase: t.eventBase(), X: pos.X, Y: pos.Y})
}

func (t *dragDropEventTarget) DragLeave() {
	t.pushEvent(&DisplayDragLeaveEvent{EventBase: t.eventBase()})
}

func (t *dragDropEventTarget) Drop(pos geom.PointF32, files []string) {
	t.pushEvent(&DisplayDropEvent{EventBase: t.eventBase(), X: pos.X, Y: pos.Y, Files: files})
}