// SPDX-FileCopyrightText: Copyright Orangebot, Inc. and Medplum contributors
// SPDX-License-Identifier: Apache-2.0
/**
* Like Array#flatMap(), but breaks out of the iteration once
* the maxCount of results has been reached. Passes the remaining
* count to be used into the mapper function as an extra argument.
* @param arr - The array to flatMap over
* @param mapper - The callback for each array entry to be passed to
* @param maxCount - The maximum size of the result array
* @returns An array representing the result of calling the mapper with each
* element of the input array, capped at length `maxCount`
*/
export function flatMapMax<T, R>(
arr: T[],
mapper: (obj: T, idx: number, count: number) => R | R[],
maxCount: number
): R[] {
let result: R[] = [];
for (const [idx, obj] of arr.entries()) {
result = result.concat(mapper(obj, idx, maxCount - result.length));
if (result.length >= maxCount) {
break;
}
}
if (result.length > maxCount) {
return result.slice(0, maxCount);
}
return result;
}
