const PRACTICE_TYPES = new Set(["open_practice", "free_practice", "practice", "qualification"]);

export function normalizeSessionReplayPassings(passings) {
  return (Array.isArray(passings) ? passings : [])
    .filter((passing) => Number.isFinite(Number(passing?.timestamp)))
    .map((passing, index) => ({
      ...passing,
      replayIndex: index,
      timestamp: Number(passing.timestamp),
      lapMs: Math.max(0, Number(passing.lapMs || 0) || 0),
      transponder: String(passing.transponder || ""),
      competitorKey: String(passing.competitorKey || passing.driverId || passing.teamId || passing.transponder || `passing_${index}`),
      driverName: String(passing.displayName || passing.teamName || passing.driverName || passing.transponder || "Unknown"),
      carName: String(passing.subLabel || passing.carName || ""),
    }))
    .sort((left, right) => left.timestamp - right.timestamp || left.replayIndex - right.replayIndex);
}

export function createSessionReplayRuntime() {
  return {
    sessionId: "",
    sessionType: "",
    sessionName: "",
    status: "idle",
    speed: 1,
    elapsedMs: 0,
    durationMs: 0,
    startedWallAt: 0,
    startedElapsedMs: 0,
    passings: [],
    timer: null,
  };
}

export function loadSessionReplay(runtime, session, result) {
  const passings = normalizeSessionReplayPassings(result?.passings);
  runtime.sessionId = String(session?.id || "");
  runtime.sessionType = String(session?.type || "");
  runtime.sessionName = String(session?.name || "");
  runtime.status = passings.length ? "paused" : "empty";
  runtime.elapsedMs = 0;
  runtime.durationMs = passings.length > 1 ? Math.max(0, passings[passings.length - 1].timestamp - passings[0].timestamp) : 0;
  runtime.startedWallAt = 0;
  runtime.startedElapsedMs = 0;
  runtime.passings = passings;
  return runtime;
}

export function playSessionReplay(runtime, nowTs = Date.now()) {
  if (!runtime.passings.length) return false;
  if (runtime.elapsedMs >= runtime.durationMs && runtime.durationMs > 0) runtime.elapsedMs = 0;
  runtime.status = "running";
  runtime.startedWallAt = nowTs;
  runtime.startedElapsedMs = runtime.elapsedMs;
  return true;
}

export function pauseSessionReplay(runtime, nowTs = Date.now()) {
  if (runtime.status !== "running") return false;
  advanceSessionReplay(runtime, nowTs);
  runtime.status = "paused";
  return true;
}

export function resetSessionReplay(runtime) {
  runtime.status = runtime.passings.length ? "paused" : "idle";
  runtime.elapsedMs = 0;
  runtime.startedWallAt = 0;
  runtime.startedElapsedMs = 0;
  return runtime;
}

export function setSessionReplaySpeed(runtime, speed, nowTs = Date.now()) {
  if (runtime.status === "running") {
    advanceSessionReplay(runtime, nowTs);
    runtime.startedWallAt = nowTs;
    runtime.startedElapsedMs = runtime.elapsedMs;
  }
  runtime.speed = [1, 2, 5, 10].includes(Number(speed)) ? Number(speed) : 1;
  return runtime.speed;
}

export function advanceSessionReplay(runtime, nowTs = Date.now()) {
  if (runtime.status !== "running") return runtime.elapsedMs;
  const advanced = runtime.startedElapsedMs + Math.max(0, nowTs - runtime.startedWallAt) * runtime.speed;
  runtime.elapsedMs = Math.min(runtime.durationMs, advanced);
  if (runtime.elapsedMs >= runtime.durationMs) runtime.status = "finished";
  return runtime.elapsedMs;
}

export function buildSessionReplaySnapshot(runtime) {
  const firstTimestamp = runtime.passings[0]?.timestamp || 0;
  const cutoff = firstTimestamp + Math.max(0, runtime.elapsedMs);
  const visiblePassings = runtime.passings.filter((passing, index) => index === 0 || passing.timestamp <= cutoff);
  const competitors = new Map();

  visiblePassings.forEach((passing) => {
    const key = passing.competitorKey;
    const row = competitors.get(key) || {
      key,
      driverName: passing.driverName,
      carName: passing.carName,
      transponder: passing.transponder,
      laps: 0,
      bestLapMs: 0,
      lastLapMs: 0,
      firstTimestamp: passing.timestamp,
      lastTimestamp: passing.timestamp,
    };
    row.driverName = passing.driverName || row.driverName;
    row.carName = passing.carName || row.carName;
    row.transponder = passing.transponder || row.transponder;
    row.lastTimestamp = passing.timestamp;
    if (passing.validLap !== false && passing.lapMs > 0) {
      row.laps += 1;
      row.lastLapMs = passing.lapMs;
      row.bestLapMs = row.bestLapMs ? Math.min(row.bestLapMs, passing.lapMs) : passing.lapMs;
    }
    competitors.set(key, row);
  });

  const practiceRanking = PRACTICE_TYPES.has(runtime.sessionType);
  const leaderboard = [...competitors.values()]
    .map((row) => ({ ...row, totalMs: Math.max(0, row.lastTimestamp - row.firstTimestamp) }))
    .sort((left, right) => {
      if (practiceRanking) {
        return (left.bestLapMs || Number.MAX_SAFE_INTEGER) - (right.bestLapMs || Number.MAX_SAFE_INTEGER)
          || right.laps - left.laps
          || left.driverName.localeCompare(right.driverName);
      }
      return right.laps - left.laps || left.totalMs - right.totalMs || left.driverName.localeCompare(right.driverName);
    });

  return {
    status: runtime.status,
    elapsedMs: runtime.elapsedMs,
    durationMs: runtime.durationMs,
    progress: runtime.durationMs ? Math.min(1, runtime.elapsedMs / runtime.durationMs) : visiblePassings.length ? 1 : 0,
    visiblePassings,
    latestPassing: visiblePassings[visiblePassings.length - 1] || null,
    leaderboard,
  };
}