import { makeAutoObservable, reaction, toJS } from "mobx";
import type { WorldState } from "./worldState";
import type { Game, Pos3, RuntimeGameScene } from "../types";
import type { CameraProps } from "@react-three/fiber";
import { GameEventBus, GameFactory } from "../model/gameFactory";
import { GameScheduler } from "../model/gameScheduler";
import type { GameEventContext } from "../types/runtime/gameBus";

export class GameState {
    private readonly world: WorldState;

    public isPaused: boolean = false;
    public time: number = 0;
    public isFirstTick: boolean;
    public scene: RuntimeGameScene;

    private eventBus: GameEventBus;
    private scheduler: GameScheduler;

    private startAutoSave() {
        return reaction(
            () => (this.asGame),
            (data) => this.saveData(data),
            { delay: 5000 }
        );
    }

    // @ts-expect-error -- for future use
    private withoutAutoSave(fn: () => void) {
        this._stopAutoSave();
        fn();
        this._stopAutoSave = this.startAutoSave();
    }

    private _stopAutoSave: () => void = () => { };

    constructor(world: WorldState) {
        this.world = world;

        const rawWorld = toJS(this.world.data);

        const game = GameFactory.create(rawWorld);
        this.isPaused = game.paused;
        this.time = game.time;
        this.isFirstTick = true;
        this.scene = game.scene;

        const eventBus = new GameEventBus();
        this.eventBus = eventBus;
        this.scheduler = new GameScheduler();

        this._stopAutoSave = this.startAutoSave();
        makeAutoObservable(this);

        GameFactory.evalGameScripts(rawWorld, this.scene, eventBus, this.scheduler);
    }

    public emitEvent(event: string, context: Omit<GameEventContext, 'world' | 'scene'> = {}) {
        this.eventBus.emit(
            event,
            {
                ...context,
                world: this.world.data,
                scene: this.scene,
            },
        );
    }

    public get asGame(): Game {
        return {
            paused: toJS(this.isPaused),
            time: toJS(this.time),
            scene: toJS(this.scene),
        };
    }

    public setGame(value: Game) {
        this.isPaused = value.paused;
        this.time = value.time;
        this.scene = value.scene;
    }

    public setIsPaused(value: boolean) {
        this.isPaused = value;
    }

    public get camera(): Pos3 {
        return this.world.data.editorCamera;
    }

    public get cameraAsThree(): CameraProps {
        const cam = this.camera;
        return {
            position: cam.position,
            fov: 50,
            rotation: cam.look,
        };
    }

    // public load() {
    //     console.log('Loading game...');
    //     this.withoutAutoSave(() => {
    //         this.data = GameFactory.load() ?? GameFactory.create(this.world.data);
    //     });
    // }

    private saveData(data: Game): void {
        console.log('Saving game...');
        const stack = new Error('Saving game...').stack!.split('\n').slice(1);
        const { ...debug } = toJS(data);
        console.dir({ stack, debug });
        GameFactory.save(data);
    }

    public save(): void {
        this.saveData(this.asGame);
    }

    public resume(): void {
        this.isPaused = false;
    }

    public pause(): void {
        this.isPaused = true;
    }

    public tick(deltaTime: number): void {
        if (this.isPaused)
            return;

        this.scheduler.tick(deltaTime);
        this.time += deltaTime;

        if (this.isFirstTick) {
            this.isFirstTick = false;
            this.emitEvent('game_start');
        }
    }
}