package kernel.ui;

import haxe.ds.ReadOnlyArray;
import kernel.ui.TermWriteable;
import kernel.peripherals.Peripherals.Peripheral;

/**
	Responsable for creating window context, forwarding UI events to the context
	and switching context to real screens.
**/
class WindowManager {
	/**
		Depends on: KernelEvents, Peripheral
	**/
	public static var instance:WindowManager;
	private var currentMainContext:WindowContext;
	private final allContexts:Array<WindowContext> = new Array();
	private final outputMap:Map<String, WindowContext> = new Map();

	@:allow(kernel.Init)
	private function new() {
		KernelEvents.instance.onKey.handle(params -> {
			if (currentMainContext != null) {
				currentMainContext.onKeyTrigger.trigger(params);
			}
		});

		KernelEvents.instance.onKeyUp.handle(keyCode -> {
			if (currentMainContext != null) {
				currentMainContext.onKeyUpTrigger.trigger(keyCode);
			}
		});

		KernelEvents.instance.onMouseClick.handle(params -> {
			if (currentMainContext != null) {
				currentMainContext.onClickTrigger.trigger(params);
			}
		});

		KernelEvents.instance.onMouseDrag.handle(params -> {
			if (currentMainContext != null) {
				currentMainContext.onMouseDragTrigger.trigger(params);
			}
		});

		KernelEvents.instance.onMouseScroll.handle(params -> {
			if (currentMainContext != null) {
				currentMainContext.onMouseScrollTrigger.trigger(params);
			}
		});

		KernelEvents.instance.onMouseUp.handle(params -> {
			if (currentMainContext != null) {
				currentMainContext.onMouseUpTrigger.trigger(params);
			}
		});

		KernelEvents.instance.onPaste.handle(text -> {
			if (currentMainContext != null) {
				currentMainContext.onPasteTrigger.trigger(text);
			}
		});

		KernelEvents.instance.onMonitorTouch.handle(params -> {
			// TODO
		});

		KernelEvents.instance.onChar.handle(char -> {
			if (currentMainContext != null) {
				currentMainContext.onCharTrigger.trigger(char);
			}
		});
	}

	public function createNewContext():WindowContext {
		var newContext = new WindowContext(new VirtualTermWriter());

		allContexts.push(newContext);

		return newContext;
	}

	public function getOutputs():ReadOnlyArray<String> {
		var arr = Peripheral.instance.getScreens().map(screen -> return screen.getAddr());
		arr.push("main");
		return arr;
	}

	public function focusContextToOutput(context:WindowContext, output:String) {
		var target:TermWriteable;
		if (output == "main") {
			target = MainTerm.instance;
			currentMainContext = context;
		} else {
			target = Peripheral.instance.getScreen(output);

			if (target == null) {
				// output target not found
				return;
			}
		}

		if (outputMap.exists(output)) {
			outputMap[output].disable();
		}

		outputMap[output] = context;
		context.setTarget(target);
		context.enable();
	}
}