//================================================================
/**
 * @packageDocumentation
 * @module std.internal
 */
//================================================================
export namespace SafeLock {
    export async function lock(
        locker: () => Promise<void>,
        unlocker: () => Promise<void>,
        lambda: () => void | Promise<void>,
    ): Promise<void> {
        await locker();
        await _Process(unlocker, lambda);
    }

    export async function try_lock(
        locker: () => Promise<boolean>,
        unlocker: () => Promise<void>,
        lambda: () => void | Promise<void>,
    ): Promise<boolean> {
        if ((await locker()) === false) return false;

        await _Process(unlocker, lambda);
        return true;
    }

    async function _Process(
        unlocker: () => Promise<void>,
        lambda: () => void | Promise<void>,
    ): Promise<void> {
        // PROCESS THE CRITICAL SECTION
        try {
            await lambda();
        } catch (error) {
            await unlocker();
            throw error;
        }

        // TERMINATE THE CRITICAL SECTION
        await unlocker();
    }
}