RocketChat/Rocket.Chat

import type { AppPermission } from '@rocket.chat/core-typings';
import { unzipSync, strFromU8 } from 'fflate';

type Uint8ArrayObject = { [fileName: string]: Uint8Array };
type AppManifestSchema = { id: string; name: string; permissions: AppPermission[] };

async function fileToUint8Array(file: File): Promise<Uint8Array> {
    return new Promise((resolve, reject) => {
        const fileReader = new FileReader();
        fileReader.onload = (e): void => resolve(new Uint8Array((e.target as any).result as Uint8Array));
        fileReader.onerror = (e): void => reject(e);
        fileReader.readAsArrayBuffer(file);
    });
}

function unzipAppBuffer(zippedAppBuffer: Uint8Array): Uint8ArrayObject {
    return unzipSync(zippedAppBuffer);
}

function getAppManifest(unzippedAppBuffer: Uint8ArrayObject): AppManifestSchema {
    if (!unzippedAppBuffer['app.json']) {
        throw new Error('No app.json file found in the zip');
    }

    try {
        return JSON.parse(strFromU8(unzippedAppBuffer['app.json']));
    } catch (e) {
        throw new Error(`Failed to parse app.json: ${e instanceof Error ? e.message : String(e)}`);
    }
}

async function unzipZippedApp(zippedApp: File | Uint8Array): Promise<Uint8ArrayObject> {
    try {
        if (zippedApp instanceof File) {
            zippedApp = await fileToUint8Array(zippedApp);
        }

        return unzipAppBuffer(zippedApp);
    } catch (e) {
        console.error(e);
        throw e;
    }
}

export async function getManifestFromZippedApp(zippedApp: File): Promise<AppManifestSchema> {
    const unzippedBuffer = await unzipZippedApp(zippedApp);
    return getAppManifest(unzippedBuffer);
}