// hooks/lib/approval-record.mjs
// What the person was asked. pre-bash-executor.mjs writes one record per
// asked call, keyed by session_id + tool_use_id (both in PreToolUse and
// PostToolUse input); post-approval-log.mjs takes it after the call ran and
// logs exactly that -- never a re-reading of the command afterwards, which
// can see another branch than the one the question named. No record = the
// person was not asked = nothing is logged.
//
// Records live in the OS temp dir (voyage-approvals-<uid>/), are removed when taken,
// and anything older than a day is swept on the next write.

import { mkdirSync, writeFileSync, readFileSync, rmSync, readdirSync, statSync } from 'node:fs';
import { createHash } from 'node:crypto';
import { tmpdir } from 'node:os';
import { join } from 'node:path';

// One directory per user: another user's directory in a shared /tmp is never ours.
const DIR = join(tmpdir(), `voyage-approvals-${process.getuid ? process.getuid() : 'u'}`);
const MAX_AGE_MS = 24 * 60 * 60 * 1000;

function pathFor(sessionId, toolUseId) {
  const key = createHash('sha256').update(`${sessionId || ''}\n${toolUseId}`).digest('hex').slice(0, 32);
  return join(DIR, `${key}.json`);
}

function sweep() {
  try {
    const now = Date.now();
    for (const f of readdirSync(DIR)) {
      const p = join(DIR, f);
      try { if (now - statSync(p).mtimeMs > MAX_AGE_MS) rmSync(p, { force: true }); } catch { /* raced */ }
    }
  } catch { /* no dir yet */ }
}

/** @returns {boolean} written */
export function writeApprovalRecord(sessionId, toolUseId, record) {
  if (!toolUseId) return false;
  try {
    mkdirSync(DIR, { recursive: true });
    sweep();
    writeFileSync(pathFor(sessionId, toolUseId), JSON.stringify(record));
    return true;
  } catch {
    return false;
  }
}

/** Read and remove the record; null when there is none. */
export function takeApprovalRecord(sessionId, toolUseId) {
  if (!toolUseId) return null;
  const p = pathFor(sessionId, toolUseId);
  try {
    const rec = JSON.parse(readFileSync(p, 'utf8'));
    rmSync(p, { force: true });
    return rec;
  } catch {
    return null;
  }
}