import { makeAutoObservable } from "mobx";
import type { ObjectInstance, ObjectType } from "../types";
import { MobxReconcilerMap } from '../utils/reconciler';
import { ObjectGeometryViewItem, ObjectTypeGeometryViewItem, ControlledCameraViewItem, ViewItem } from './viewLayers';
import type { WorldState } from "./worldState";
import { ObjectSelectionViewItem } from "./viewLayers/objectSelection";
import type { WorldEditorState } from "./worldEditorState";

export class ViewState {
    public objectTypeGeometries: MobxReconcilerMap<ObjectType, ObjectTypeGeometryViewItem>;
    public objectGeometries: MobxReconcilerMap<ObjectInstance, ObjectGeometryViewItem>;
    public camera?: ControlledCameraViewItem;

    private readonly editor: WorldEditorState;

    constructor(world: WorldState, editor: WorldEditorState) {
        this.editor = editor;

        makeAutoObservable(
            this,
        );

        this.camera = new ControlledCameraViewItem();

        this.objectTypeGeometries = new MobxReconcilerMap<ObjectType, ObjectTypeGeometryViewItem>({
            reaction: () => Object.values(world.data.objectTypes),
            keyOf: (ot) => ot.id,
            mapItem: (ot) => new ObjectTypeGeometryViewItem(this, ot),
            updateItem: () => true,
            disposeItem: (item) => { item.dispose(); },
        });

        this.objectGeometries = new MobxReconcilerMap<ObjectInstance, ObjectGeometryViewItem>({
            reaction: () => Object.values(world.data.initialScene.objects)
                .filter(obj => obj.visible)
                .filter(obj => !!world.data.objectTypes[obj.typeId]),
            keyOf: (obj) => obj.id,
            mapItem: (obj) => new ObjectGeometryViewItem(obj, this.objectTypeGeometries.get(obj.typeId)!),
        });
    }

    public dispose(): void {
        this.objectTypeGeometries.dispose();
        this.objectGeometries.dispose();
    }

    public get selectedObject(): ObjectSelectionViewItem | undefined {
        const sel = this.editor.selection;
        if (sel?.type !== 'object')
            return;

        const geom = this.objectGeometries.get(sel.id);
        if (!geom)
            return;

        return new ObjectSelectionViewItem(geom, sel.editMode);
    }

    public get items(): ViewItem[] {
        return [
            ...this.objectTypeGeometries,
            ...this.objectGeometries,
            ...[this.camera ? [this.camera] : []],
            ...[this.selectedObject ? [this.selectedObject] : []],
        ];
    }
}