import fs from 'node:fs';
import os from 'node:os';
import path from 'node:path';
import { afterAll } from 'vitest';

const originalTempEnv = {
    TMPDIR: process.env.TMPDIR,
    TMP: process.env.TMP,
    TEMP: process.env.TEMP,
};
const originalCwd = process.cwd();
const testTempDir = fs.mkdtempSync(
    path.join(
        os.tmpdir(),
        `snowluma-onebot-vitest-${process.pid}-${process.env.VITEST_POOL_ID ?? '0'}-`,
    ),
);

process.env.TMPDIR = testTempDir;
process.env.TMP = testTempDir;
process.env.TEMP = testTempDir;

// Runtime state resolves against cwd, not the package root: `config/onebot_<uin>.json`
// (the `persistDefaults` materialization) and the per-UIN stores under `data/`. The
// manager's real session-start path persists that config even when a test injects a
// fake instance, so `manager-lifecycle.test.ts` alone left
// `packages/onebot/config/onebot_10001.json` behind — an untracked file carrying a
// generated access token that dirtied `git status` (and `git add -A`) on every run.
// Pin cwd to this worker's temp dir so each relative write stays contained. Vitest
// runs one file per forked process, so the chdir cannot cross into another file.
process.chdir(testTempDir);

// The package root must stay untouched by tests. Snapshot it before the suite so an
// operator-created directory (or a leftover from an earlier run) is never blamed on
// the current one.
const rootEntriesBefore = new Set(fs.readdirSync(originalCwd));

afterAll(() => {
    // Leave the temp dir before deleting it.
    process.chdir(originalCwd);

    for (const [name, value] of Object.entries(originalTempEnv)) {
        if (value === undefined) {
            delete process.env[name];
        } else {
            process.env[name] = value;
        }
    }

    fs.rmSync(testTempDir, { recursive: true, force: true });

    const added = fs.readdirSync(originalCwd).filter((name) => !rootEntriesBefore.has(name));

    if (added.length > 0) {
        throw new Error(
            `OneBot tests created ${added.join(', ')} in ${originalCwd}. Runtime state must resolve ` +
                'under the per-worker temp dir this setup chdir-s into; a test that switches cwd itself ' +
                'must restore it before its asynchronous work settles.',
        );
    }
});