import { FreeCamera, Observable, Scene, Vector2 } from "@babylonjs/core";

/**
 * Handles keyboard and mouse input for ship control
 * Combines both input methods into a unified interface
 */
export class KeyboardInput {
    private _leftStick: Vector2 = Vector2.Zero();
    private _rightStick: Vector2 = Vector2.Zero();
    private _mouseDown: boolean = false;
    private _mousePos: Vector2 = new Vector2(0, 0);
    private _onShootObservable: Observable<void> = new Observable<void>();
    private _onCameraChangeObservable: Observable<number> = new Observable<number>();
    private _scene: Scene;

    constructor(scene: Scene) {
        this._scene = scene;
    }

    /**
     * Get observable that fires when shoot key/button is pressed
     */
    public get onShootObservable(): Observable<void> {
        return this._onShootObservable;
    }

    /**
     * Get observable that fires when camera change key is pressed
     */
    public get onCameraChangeObservable(): Observable<number> {
        return this._onCameraChangeObservable;
    }

    /**
     * Get current input state (stick positions)
     */
    public getInputState() {
        return {
            leftStick: this._leftStick.clone(),
            rightStick: this._rightStick.clone(),
        };
    }

    /**
     * Setup keyboard and mouse event listeners
     */
    public setup(): void {
        this.setupKeyboard();
        this.setupMouse();
    }

    /**
     * Setup keyboard event listeners
     */
    private setupKeyboard(): void {
        document.onkeyup = () => {
            this._leftStick.y = 0;
            this._leftStick.x = 0;
            this._rightStick.y = 0;
            this._rightStick.x = 0;
        };

        document.onkeydown = (ev) => {
            switch (ev.key) {
                case '1':
                    this._onCameraChangeObservable.notifyObservers(1);
                    break;
                case ' ':
                    this._onShootObservable.notifyObservers();
                    break;
                case 'e':
                    break;
                case 'w':
                    this._leftStick.y = -1;
                    break;
                case 's':
                    this._leftStick.y = 1;
                    break;
                case 'a':
                    this._leftStick.x = -1;
                    break;
                case 'd':
                    this._leftStick.x = 1;
                    break;
                case 'ArrowUp':
                    this._rightStick.y = -1;
                    break;
                case 'ArrowDown':
                    this._rightStick.y = 1;
                    break;
            }
        };
    }

    /**
     * Setup mouse event listeners for drag-based rotation control
     */
    private setupMouse(): void {
        this._scene.onPointerDown = (evt) => {
            this._mousePos.x = evt.x;
            this._mousePos.y = evt.y;
            this._mouseDown = true;
        };

        this._scene.onPointerUp = () => {
            this._mouseDown = false;
        };

        this._scene.onPointerMove = (ev) => {
            if (!this._mouseDown) {
                return;
            }

            const xInc = (ev.x - this._mousePos.x) / 100;
            const yInc = (ev.y - this._mousePos.y) / 100;

            if (Math.abs(xInc) <= 1) {
                this._rightStick.x = xInc;
            } else {
                this._rightStick.x = Math.sign(xInc);
            }

            if (Math.abs(yInc) <= 1) {
                this._rightStick.y = yInc;
            } else {
                this._rightStick.y = Math.sign(yInc);
            }
        };
    }

    /**
     * Cleanup event listeners
     */
    public dispose(): void {
        document.onkeydown = null;
        document.onkeyup = null;
        this._scene.onPointerDown = null;
        this._scene.onPointerUp = null;
        this._scene.onPointerMove = null;
        this._onShootObservable.clear();
        this._onCameraChangeObservable.clear();
    }
}