window.ISR = window.ISR || {};

// ── LRU Track Cache ──────────────────────────────────────────────

const TRACK_CACHE = new Map();
const TRACK_CACHE_MAX = 100;
function cacheTrackData(frameIdx, data) {
  if (TRACK_CACHE.size >= TRACK_CACHE_MAX) {
    const oldest = TRACK_CACHE.keys().next().value;
    TRACK_CACHE.delete(oldest);
  }
  TRACK_CACHE.set(frameIdx, data);
}
function getCachedTracks(frameIdx) {
  if (!TRACK_CACHE.has(frameIdx)) return null;
  const data = TRACK_CACHE.get(frameIdx);
  TRACK_CACHE.delete(frameIdx);
  TRACK_CACHE.set(frameIdx, data); // promote to most-recent
  return data;
}
function clearTrackCache() { TRACK_CACHE.clear(); }

// ── Assessment Cache ───────────────────────────────────────────────
// Carries GPT assessment data forward across frames per track_id

const ASSESSMENT_CACHE = {}; // track_id → {satisfies, reason, mission_relevant, features, gpt_raw, assessment_status}

function cacheAssessment(trackId, data) {
  if (!trackId) return;
  if (!ASSESSMENT_CACHE[trackId]) ASSESSMENT_CACHE[trackId] = {};
  const c = ASSESSMENT_CACHE[trackId];
  if (data.gpt_raw !== undefined) c.gpt_raw = data.gpt_raw;
  if (data.satisfies !== undefined) c.satisfies = data.satisfies;
  if (data.reason !== undefined) c.reason = data.reason;
  if (data.mission_relevant !== undefined) c.mission_relevant = data.mission_relevant;
  if (data.features !== undefined) c.features = data.features;
  if (data.assessment_status !== undefined) c.assessment_status = data.assessment_status;
}

function applyAssessmentCache(track) {
  const tid = track.track_id !== undefined ? track.track_id : track.id;
  // Cache new data if present (matches frontend tracker.js Phase 1)
  if (track.gpt_raw || track.assessment_status === 'ASSESSED') {
    cacheAssessment(tid, track);
  }
  // Apply cached data if track is missing gpt_raw (matches frontend tracker.js Phase 2)
  if (track.gpt_raw) return track; // Already has assessment data, skip
  const cached = ASSESSMENT_CACHE[tid];
  if (!cached) return track;
  track.gpt_raw = cached.gpt_raw;
  if (cached.satisfies !== undefined) track.satisfies = cached.satisfies ?? track.satisfies;
  track.reason = cached.reason || track.reason;
  if (cached.mission_relevant !== undefined) track.mission_relevant = cached.mission_relevant ?? track.mission_relevant;
  track.assessment_status = cached.assessment_status || 'ASSESSED';
  if (cached.features && Object.keys(cached.features).length > 0) track.features = cached.features;
  return track;
}

function clearAssessmentCache() {
  for (const k of Object.keys(ASSESSMENT_CACHE)) delete ASSESSMENT_CACHE[k];
}

// ── Export to namespace ─────────────────────────────────────────

Object.assign(window.ISR, {
  TRACK_CACHE,
  ASSESSMENT_CACHE,
  cacheTrackData,
  getCachedTracks,
  clearTrackCache,
  cacheAssessment,
  applyAssessmentCache,
  clearAssessmentCache,
});