RocketChat/Rocket.Chat

export const fileUploadMediaWhiteList = function (customWhiteList: string): string[] | undefined {
    const mediaTypeWhiteList = customWhiteList;

    if (!mediaTypeWhiteList || mediaTypeWhiteList === '*') {
        return;
    }
    return mediaTypeWhiteList.split(',').map((item) => {
        return item.trim();
    });
};

const fileUploadMediaBlackList = function (customBlackList: string): string[] | undefined {
    const blacklist = customBlackList;
    if (!blacklist) {
        return;
    }

    return blacklist.split(',').map((item) => item.trim());
};

const isTypeOnList = function (type?: string, list?: string[]): boolean {
    if (!type || !list) {
        return false;
    }

    if (list.includes(type)) {
        return true;
    }
    const wildCardGlob = '/*';
    const wildcards = list.filter((item) => {
        return item.indexOf(wildCardGlob) > 0;
    });
    if (wildcards.includes(type.replace(/(\/.*)$/, wildCardGlob))) {
        return true;
    }

    return false;
};

export const fileUploadIsValidContentTypeFromSettings = function (
    type: string | undefined,
    customWhiteList: string,
    customBlackList: string,
): boolean {
    const blackList = fileUploadMediaBlackList(customBlackList);
    const whiteList = fileUploadMediaWhiteList(customWhiteList);

    if (blackList && type && isTypeOnList(type, blackList)) {
        return false;
    }

    if (whiteList) {
        return isTypeOnList(type, whiteList);
    }

    if (!whiteList) {
        return true;
    }

    return false;
};