import { GetObjectCommand } from "@aws-sdk/client-s3"
import { s3 } from "./s3"
import { secrets } from "./secrets"

export const streamToBuffer = async (stream: any, maxBytes = Infinity): Promise<Buffer> => {
    const chunks: Buffer[] = []
    let size = 0

    for await (const chunk of stream) {
        const buffer = Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk)
        size += buffer.length
        if (size > maxBytes) throw new Error("Die Datei ist für Base64 zu groß. Bitte den Download mit format: url verwenden.")
        chunks.push(buffer)
    }

    return Buffer.concat(chunks)
}

export const loadFileBuffer = async (path: string, maxBytes = Infinity): Promise<Buffer> => {
    const response = await s3.send(new GetObjectCommand({
        Bucket: secrets.S3_BUCKET,
        Key: path,
    }))

    if (!response.Body) {
        throw new Error(`S3-Datei '${path}' enthält keinen lesbaren Inhalt.`)
    }

    return streamToBuffer(response.Body, maxBytes)
}