import { mkdir, mkdtemp, rm, writeFile } from 'node:fs/promises';
import { tmpdir } from 'node:os';
import { join } from 'node:path';

export interface Fixture {
    root: string;
    shared: string;
    staging: string;
    t5: string;
    dbPath: string;
    cleanup: () => Promise<void>;
}

/**
 * Build a zombies/ tree in a temp dir and point env at it BEFORE the code
 * under test is imported. Returns paths + a cleanup fn.
 */
export async function newFixture(files: Record<string, string> = {}, servers: string[] = ['t5_kino_1']): Promise<Fixture> {
    const root = await mkdtemp(join(tmpdir(), 'cherry-'));
    const shared = join(root, 'shared/scripts');
    const staging = join(shared, 'betas');
    const t5 = join(root, 't5');
    const dbPath = join(root, 'cherry.db');
    await mkdir(staging, { recursive: true });
    await mkdir(t5, { recursive: true });

    for (const [rel, body] of Object.entries(files)) {
        const p = join(shared, rel);
        await mkdir(join(p, '..'), { recursive: true });
        await writeFile(p, body);
    }
    for (const s of servers) {
        await mkdir(join(t5, s, 'runtime/plutonium/storage/t5/raw/scripts/sp'), { recursive: true });
    }

    process.env.SHARED_SCRIPTS = shared;
    process.env.SERVERS_ROOT = t5;
    process.env.REL_DEST = 'runtime/plutonium/storage/t5/raw/scripts/sp';
    process.env.DB_PATH = dbPath;
    process.env.DEPLOY_KEEP_DAYS = '7';
    process.env.HTTP_TIMEOUT_MS = '2000';

    return {
        root,
        shared,
        staging,
        t5,
        dbPath,
        cleanup: async () => {
            // On Windows the SQLite handle keeps a lock on cherry.db-shm/wal
            // and rmdir refuses to remove the temp tree. Close the singleton
            // (if this test imported it) before removing the dir. Fresh
            // dynamic import so we grab whatever handle the test opened.
            try {
                const mod = (await import('../../src/lib/server/db/index.js')) as {
                    closeDb: () => void;
                };
                mod.closeDb();
            } catch {
                /* db module was never loaded — nothing to close */
            }
            await rm(root, { recursive: true, force: true, maxRetries: 5, retryDelay: 50 });
        }
    };
}

/**
 * Fresh module-level state. Vitest caches modules per file — this forces a
 * re-import so the tests can rebuild the singleton DB handle against a new
 * fixture.
 */
export async function importFresh<T>(mod: string): Promise<T> {
    return (await import(`${mod}?t=${Date.now()}${Math.random()}`)) as T;
}