ds4/src/module/active-effect.ts

// SPDX-FileCopyrightText: 2021 Johannes Loher
//
// SPDX-License-Identifier: MIT

import { DS4Actor } from "./actor/actor";
import { getGame } from "./helpers";

declare global {
    interface DocumentClassConfig {
        ActiveEffect: typeof DS4ActiveEffect;
    }
}

type PromisedType<T> = T extends Promise<infer U> ? U : T;
export class DS4ActiveEffect extends ActiveEffect {
    /**
     * A cached reference to the source document to avoid recurring database lookups
     */
    protected source: PromisedType<ReturnType<typeof fromUuid>> | undefined = undefined;

    /** @override */
    apply(actor: DS4Actor, change: foundry.data.ActiveEffectData["changes"][number]): unknown {
        change.value = Roll.replaceFormulaData(change.value, actor.data);
        try {
            change.value = Roll.safeEval(change.value).toString();
        } catch (e) {
            // this is a valid case, e.g., if the effect change simply is a string
        }
        return super.apply(actor, change);
    }

    /**
     * Gets the current source name based on the cached source object.
     */
    async getCurrentSourceName(): Promise<string> {
        const game = getGame();
        const origin = await this.getSource();
        if (origin === null) return game.i18n.localize("None");
        return origin.name ?? game.i18n.localize("Unknown");
    }

    /**
     * Gets the source document for this effect. Uses the cached {@link DS4ActiveEffect#origin} if it has already been
     * set.
     */
    protected async getSource(): ReturnType<typeof fromUuid> {
        if (this.source === undefined) {
            this.source = this.data.origin !== undefined ? await fromUuid(this.data.origin) : null;
        }
        return this.source;
    }
}