/**
 * Simulation Statistics & History Tracking
 * Keeps full account of births, deaths, consumption, and temporal population data for charting.
 */

export class SimStats {
  constructor() {
    this.reset();
  }

  reset() {
    this.startTime = Date.now();
    this.elapsedSimTime = 0; // simulated seconds

    // Historical population records (sampled at 1Hz sim time)
    this.history = [];
    this.sampleTimer = 0;

    // Entity counters
    this.totalSheepBorn = 0;
    this.totalWolvesBorn = 0;
    this.totalPlantsGrown = 0;
    this.totalPlantsFromDecay = 0;
    this.totalSeedsSprouted = 0;

    // Death counters
    this.sheepKilledByWolves = 0;
    this.sheepStarved = 0;
    this.wolvesStarved = 0;
    this.plantsEaten = 0;
    this.plantsWithered = 0;

    // Peaks
    this.peakSheep = 0;
    this.peakWolves = 0;
    this.peakPlants = 0;

    // Extinction flag
    this.extinct = false;
    this.extinctionTime = 0;
  }

  update(dt, sheepCount, wolfCount, plantCount) {
    this.elapsedSimTime += dt;

    if (sheepCount > this.peakSheep) this.peakSheep = sheepCount;
    if (wolfCount > this.peakWolves) this.peakWolves = wolfCount;
    if (plantCount > this.peakPlants) this.peakPlants = plantCount;

    // Sample population every 1 simulated second for graphs
    this.sampleTimer += dt;
    if (this.sampleTimer >= 1.0) {
      this.sampleTimer -= 1.0;
      this.history.push({
        time: Math.round(this.elapsedSimTime),
        sheep: sheepCount,
        wolves: wolfCount,
        plants: plantCount,
      });

      // Keep up to 600 data points (10 minutes of active history)
      if (this.history.length > 600) {
        this.history.shift();
      }
    }

    // Check for extinction event (both animal populations reach 0 after starting)
    if (!this.extinct && this.elapsedSimTime > 2.0 && sheepCount === 0 && wolfCount === 0) {
      this.extinct = true;
      this.extinctionTime = this.elapsedSimTime;
    }
  }

  recordSheepBirth(isInitial = false) {
    if (!isInitial) this.totalSheepBorn++;
  }

  recordWolfBirth(isInitial = false) {
    if (!isInitial) this.totalWolvesBorn++;
  }

  recordPlantSpawn(isFromDecay = false, isFromSeed = false) {
    this.totalPlantsGrown++;
    if (isFromDecay) this.totalPlantsFromDecay++;
    if (isFromSeed) this.totalSeedsSprouted++;
  }

  recordSheepDeath(cause = 'wolf') {
    if (cause === 'wolf') {
      this.sheepKilledByWolves++;
    } else {
      this.sheepStarved++;
    }
  }

  recordWolfDeath(cause = 'starvation') {
    this.wolvesStarved++;
  }

  recordPlantConsumed() {
    this.plantsEaten++;
  }

  recordPlantWithered() {
    this.plantsWithered++;
  }
}