import path from "node:path";

import { afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "vitest";

import { withEnvAsync } from "../test-utils/env.js";

import { decodeStrictBase64 } from "./subagent-attachments.js";

import {

createSubagentSpawnTestConfig,

loadSubagentSpawnModuleForTest,

const maxBytes = 1024;

it("valid base64 returns buffer with correct bytes", () => {

const { decodeStrictBase64 } = subagentSpawnModule;

const input = "hello world";

const encoded = Buffer.from(input).toString("base64");

const result = decodeStrictBase64(encoded, maxBytes);

expect(result?.toString("utf8")).toBe(input);

});

it("empty string returns null", () => {

const { decodeStrictBase64 } = subagentSpawnModule;

expect(decodeStrictBase64("", maxBytes)).toBeNull();

});

it("bad padding (length % 4 !== 0) returns null", () => {

const { decodeStrictBase64 } = subagentSpawnModule;

expect(decodeStrictBase64("abc", maxBytes)).toBeNull();

});

it("non-base64 chars returns null", () => {

const { decodeStrictBase64 } = subagentSpawnModule;

expect(decodeStrictBase64("!@#$", maxBytes)).toBeNull();

});

it("whitespace-only returns null (empty after strip)", () => {

const { decodeStrictBase64 } = subagentSpawnModule;

expect(decodeStrictBase64(" ", maxBytes)).toBeNull();

});

it("pre-decode oversize guard: encoded string > maxEncodedBytes * 2 returns null", () => {

const { decodeStrictBase64 } = subagentSpawnModule;

// Pre-decode guard rejects obviously oversized payloads before allocating

// the decoded buffer.

const oversized = "A".repeat(2737);

expect(decodeStrictBase64(oversized, maxBytes)).toBeNull();

});

it("decoded byteLength exceeds maxDecodedBytes returns null", () => {

const { decodeStrictBase64 } = subagentSpawnModule;

const bigBuf = Buffer.alloc(1025, 0x42);

const encoded = bigBuf.toString("base64");

expect(decodeStrictBase64(encoded, maxBytes)).toBeNull();

});

it("valid base64 at exact boundary returns Buffer", () => {

const { decodeStrictBase64 } = subagentSpawnModule;

const exactBuf = Buffer.alloc(1024, 0x41);

const encoded = exactBuf.toString("base64");

const result = decodeStrictBase64(encoded, maxBytes);