import { cobbStandardPerformance } from '../mockData/cobbStandard.ts';

/**
 * Analyze trend of numerical data over a window
 * @param data Array of numerical values
 * @param windowSize Number of recent data points to analyze
 * @returns Trend description in Indonesian
 */
export function analyzeTrend(data: number[], windowSize = 7): string {
  if (!data || data.length < 2) {
    return 'tidak cukup data';
  }

  // Filter out invalid values (null, undefined, NaN, 0)
  const validData = data.filter((val) => val != null && !isNaN(val) && val !== 0);

  if (validData.length < 2) {
    return 'tidak cukup data';
  }

  // Take last N values
  const recentData = validData.slice(-Math.min(windowSize, validData.length));

  if (recentData.length < 2) {
    return 'tidak cukup data';
  }

  // Calculate simple linear regression slope
  const n = recentData.length;
  const xMean = (n - 1) / 2; // Mean of indices 0, 1, 2, ..., n-1
  const yMean = recentData.reduce((sum, val) => sum + val, 0) / n;

  let numerator = 0;
  let denominator = 0;

  for (let i = 0; i < n; i++) {
    numerator += (i - xMean) * ((recentData[i] ?? 0) - yMean);
    denominator += Math.pow(i - xMean, 2);
  }

  const slope = denominator !== 0 ? numerator / denominator : 0;

  // Calculate relative slope (as percentage of mean)
  const relativeSlope = yMean !== 0 ? (slope / yMean) * 100 : 0;

  // Determine trend based on relative slope
  // Threshold: >2% = increasing, <-2% = decreasing, else stable
  if (relativeSlope > 2) {
    return 'meningkat';
  } else if (relativeSlope < -2) {
    return 'menurun';
  } else {
    return 'stabil';
  }
}

/**
 * Get cycle phase based on day of cycle
 * @param day Current day of cycle (1-based)
 * @returns Phase name
 */
export function getCyclePhase(day: number): string {
  if (day <= 14) {
    return 'Brooding';
  } else if (day <= 28) {
    return 'Growth';
  } else {
    return 'Finisher';
  }
}

/**
 * Get Cobb standard performance metrics for a given day
 * @param day Day of cycle (1-based)
 * @returns Object with FCR and weight, or null if not available
 */
export function getCobbStandardForDay(day: number): { fcr: number; weight: number } | null {
  const standard = cobbStandardPerformance.find((entry) => entry.day === day);
  if (standard) {
    return {
      fcr: standard.fcr,
      // Weight targets live in page builders / CP707 knowledge; FCR row has no weight column here.
      weight: 0,
    };
  }
  return null;
}

/**
 * Calculate deviation between actual and target values
 * @param actual Actual value
 * @param target Target value
 * @returns Object with absolute and percentage deviation
 */
export function calculateDeviation(
  actual: number,
  target: number
): { absolute: number; percent: number } {
  const absolute = actual - target;
  const percent = target !== 0 ? (absolute / target) * 100 : 0;
  return { absolute, percent };
}

/**
 * Determine environmental status based on readings and cycle phase
 * @param temp Temperature in Celsius
 * @param humidity Humidity percentage
 * @param ammonia Ammonia in ppm
 * @param day Current day of cycle
 * @returns Status description in Indonesian
 */
export function getEnvironmentalStatus(
  temp: number,
  humidity: number,
  ammonia: number,
  day: number
): string {
  const issues: string[] = [];

  // Age-appropriate temperature ranges
  // Younger chicks need warmer temperatures
  let optimalTempMin: number;
  let optimalTempMax: number;

  if (day <= 7) {
    optimalTempMin = 32;
    optimalTempMax = 35;
  } else if (day <= 14) {
    optimalTempMin = 30;
    optimalTempMax = 32;
  } else if (day <= 21) {
    optimalTempMin = 28;
    optimalTempMax = 30;
  } else {
    optimalTempMin = 26;
    optimalTempMax = 28;
  }

  // Check temperature
  if (temp < optimalTempMin) {
    issues.push('suhu terlalu rendah');
  } else if (temp > optimalTempMax) {
    issues.push('suhu terlalu tinggi');
  }

  // Check humidity (optimal: 50-70%)
  if (humidity < 50) {
    issues.push('kelembapan rendah');
  } else if (humidity > 70) {
    issues.push('kelembapan tinggi');
  }

  // Check ammonia (safe: <25ppm, warning: 25-50ppm, critical: >50ppm)
  if (ammonia > 50) {
    issues.push('amonia kritis');
  } else if (ammonia > 25) {
    issues.push('amonia tinggi');
  }

  if (issues.length === 0) {
    return 'optimal';
  } else if (issues.length === 1) {
    return issues[0] ?? 'optimal';
  } else {
    return issues.join(', ');
  }
}

/**
 * Analyze feed consumption trend
 * @param feedHistory Array of daily feed consumption (in sacks)
 * @param _currentDay Current day of cycle (reserved for future use)
 * @returns Trend description in Indonesian
 */
export function analyzeFeedTrend(feedHistory: number[], _currentDay: number): string {
  if (!feedHistory || feedHistory.length < 3) {
    return 'tidak cukup data';
  }

  // Get last 7 days of feed data
  const recentFeed = feedHistory.slice(-7);

  // Rough expectation: feed consumption should increase gradually as chickens grow
  // Early days: 0.5-1 sack/1000 birds/day
  // Mid cycle: 1-2 sacks/1000 birds/day
  // Late cycle: 2-3 sacks/1000 birds/day

  // This is a simplified heuristic - in real deployment, this would be calibrated
  // based on actual farm data and population size

  // For now, just analyze if consumption is increasing (expected as birds grow)
  const trend = analyzeTrend(recentFeed, 7);

  if (trend === 'meningkat') {
    return 'sesuai pertumbuhan';
  } else if (trend === 'menurun') {
    return 'menurun (perlu perhatian)';
  } else {
    return 'stabil';
  }
}