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/**
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 * A simple mutex class to prevent concurrent updates.
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 */
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export class SimpleMutex {
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    /**
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     * @type {boolean}
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     */
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    isBusy = false;
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    /**
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     * @type {Function}
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     */
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    callback = () => {};
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    /**
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     * Constructs a SimpleMutex.
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     * @param {Function} callback Callback function.
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     */
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    constructor(callback) {
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        this.isBusy = false;
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        this.callback = callback;
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    }
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    /**
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     * Updates the mutex by calling the callback if not busy.
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     * @param  {...any} args Callback args
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     * @returns {Promise<void>}
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     */
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    async update(...args) {
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        // Don't touch me I'm busy...
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        if (this.isBusy) {
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            return;
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        }
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        // I'm free. Let's update!
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        try {
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            this.isBusy = true;
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            await this.callback(...args);
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        } finally {
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            this.isBusy = false;
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        }
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    }
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}