import { appendFileSync, mkdirSync } from 'node:fs';
import path from 'node:path';
import { PERF_DIR } from './manifest';

function pad(n: number) { return String(n).padStart(2, '0'); }

export function runId(): string {
  if (process.env.PERF_RUN_ID) return process.env.PERF_RUN_ID;
  const d = new Date();
  return `${d.getFullYear()}${pad(d.getMonth() + 1)}${pad(d.getDate())}-${pad(d.getHours())}${pad(d.getMinutes())}`;
}

/** Каталог прогона: PERF_RESULTS_DIR (тесты) или perf/results/<run_id>. */
export function runDir(): string {
  return process.env.PERF_RESULTS_DIR ?? path.join(PERF_DIR, 'results', runId());
}

export interface ResultRecord {
  run_id?: string;
  scenario: string;
  target: string;
  role: string;
  scale: number;
  cpu_rate: number;
  repeat: number;
  metrics: Record<string, number>;
  artifacts: string[];
  incomplete?: boolean;
  skip_reason?: string;
  ts?: string;
}

/** Формат — docstring perf/perfkit/results.py: perf/results/<run_id>/<scenario>.jsonl. */
export function append(rec: ResultRecord): string {
  const dir = runDir();
  mkdirSync(dir, { recursive: true });
  const full = {
    run_id: runId(),
    incomplete: false,
    ts: new Date().toISOString().replace(/\.\d+Z$/, 'Z'),
    ...rec,
  };
  const file = path.join(dir, `${rec.scenario}.jsonl`);
  appendFileSync(file, JSON.stringify(full) + '\n', 'utf-8');
  return file;
}