import {
  ScalePredictionRangeResponse,
  SensorWeightSummaryResponse,
  DailyWeightPoint,
  DailyWeightGainPoint,
  DeviceWeightData,
  WeightStatistics,
} from '../types.ts';
import { getTargetWeightForDay } from './weightUtils.ts';

const MS_PER_DAY = 24 * 60 * 60 * 1000;

interface DeviceInfo {
  id: string;
  name: string;
  status: boolean;
  last_online: string;
}

function parseDateOnly(dateString: string): Date | null {
  const [year, month, day] = dateString.split('-').map(Number);

  if (!year || !month || !day) {
    return null;
  }

  return new Date(year, month - 1, day);
}

function getDayOfCycle(dateString: string, cycleStartDate: Date): number | null {
  const pointDate = parseDateOnly(dateString);
  if (!pointDate) {
    return null;
  }

  const startDate = new Date(cycleStartDate);
  startDate.setHours(0, 0, 0, 0);
  pointDate.setHours(0, 0, 0, 0);

  const diffMs = pointDate.getTime() - startDate.getTime();
  if (diffMs < 0) {
    return null;
  }

  return Math.floor(diffMs / MS_PER_DAY) + 1;
}

/**
 * Process scale prediction range data into daily weight points
 */
export function processDailyWeightData(
  scaleData: ScalePredictionRangeResponse,
  cycleStartDate: Date,
  maxDay?: number
): DailyWeightPoint[] {
  const dailyMap = new Map<
    string,
    {
      weights: number[];
      chickenCounts: number[];
      date: string;
      day: number;
    }
  >();

  // Group data by date
  scaleData.data.forEach((dayData) => {
    const fallbackAge = dayData.items[0]?.age;
    const dayOfCycle = getDayOfCycle(dayData.date, cycleStartDate) ?? fallbackAge ?? 1;

    if (dayOfCycle < 1) {
      return;
    }

    if (maxDay !== undefined && dayOfCycle > maxDay) {
      return;
    }

    const weights: number[] = [];
    const chickenCounts: number[] = [];

    dayData.items.forEach((item) => {
      if (item.avg_weight_actual > 0 && item.chicken_count > 0) {
        weights.push(item.avg_weight_actual);
        chickenCounts.push(item.chicken_count);
      }
    });

    if (weights.length > 0) {
      dailyMap.set(dayData.date, {
        weights,
        chickenCounts,
        date: dayData.date,
        day: dayOfCycle,
      });
    }
  });

  // Convert to DailyWeightPoint array
  const result: DailyWeightPoint[] = [];

  dailyMap.forEach((dayInfo) => {
    // Calculate weighted average
    let totalWeight = 0;
    let totalChickens = 0;

    dayInfo.weights.forEach((weight, idx) => {
      const count = dayInfo.chickenCounts[idx] ?? 0;
      if (count <= 0) {
        return;
      }
      totalWeight += weight * count;
      totalChickens += count;
    });

    const avgWeight = totalChickens > 0 ? totalWeight / totalChickens : 0;

    // Skip if no actual weight data
    if (avgWeight === 0 || totalChickens === 0) {
      return;
    }

    const minWeight = Math.min(...dayInfo.weights);
    const maxWeight = Math.max(...dayInfo.weights);
    const targetWeight = getTargetWeightForDay(dayInfo.day) || 0;

    result.push({
      day: dayInfo.day,
      date: dayInfo.date,
      actual: Math.round(avgWeight),
      target: targetWeight,
      min: Math.round(minWeight),
      max: Math.round(maxWeight),
      chickenCount: totalChickens,
    });
  });

  // Sort by day
  return result.sort((a, b) => a.day - b.day);
}

/**
 * Calculate daily weight gain from daily weight data
 */
export function calculateDailyWeightGain(
  dailyWeightData: DailyWeightPoint[]
): DailyWeightGainPoint[] {
  const result: DailyWeightGainPoint[] = [];

  for (let i = 1; i < dailyWeightData.length; i++) {
    const today = dailyWeightData[i];
    const yesterday = dailyWeightData[i - 1];

    if (!today || !yesterday) {
      continue;
    }

    // Skip if either day has no actual weight
    if (!today.actual || !yesterday.actual) {
      continue;
    }

    const gain = today.actual - yesterday.actual;
    const targetGain = (today.target || 0) - (yesterday.target || 0);

    // Determine status
    let status: 'above' | 'near' | 'below';
    const threshold = Math.abs(targetGain) * 0.1; // 10% threshold

    if (gain >= targetGain + threshold) {
      status = 'above';
    } else if (gain >= targetGain - threshold) {
      status = 'near';
    } else {
      status = 'below';
    }

    result.push({
      day: today.day,
      date: today.date,
      gain,
      targetGain,
      status,
    });
  }

  return result;
}

/**
 * Process sensor summary data into device weight data
 */
export function processDeviceWeightData(
  summaryData: SensorWeightSummaryResponse,
  deviceInfoList: DeviceInfo[]
): DeviceWeightData[] {
  return summaryData.data
    .filter((sensor) => {
      // Skip devices with no weight data or no chickens
      if (
        !sensor.avg_weight_actual ||
        sensor.avg_weight_actual <= 0 ||
        !sensor.chicken_count ||
        sensor.chicken_count <= 0
      ) {
        return false;
      }
      return true;
    })
    .map((sensor) => {
      const deviceInfo = deviceInfoList.find((d) => d.id === sensor.device_id);

      return {
        deviceId: sensor.device_id,
        deviceName: sensor.device_name,
        avgWeight: Math.round(sensor.avg_weight_actual),
        chickenCount: sensor.chicken_count,
        isOnline: deviceInfo?.status ?? true,
        lastOnline: deviceInfo?.last_online ?? new Date().toISOString(),
      };
    });
}

/**
 * Calculate weight statistics from sensor summary data
 */
export function calculateWeightStatistics(
  summaryData: SensorWeightSummaryResponse,
  yesterdaySummary?: SensorWeightSummaryResponse
): WeightStatistics {
  // Calculate weighted average weight - only include sensors with data
  let totalWeight = 0;
  let totalChickens = 0;

  summaryData.data.forEach((sensor) => {
    // Skip sensors with no data
    if (sensor.avg_weight_actual > 0 && sensor.chicken_count > 0) {
      totalWeight += sensor.avg_weight_actual * sensor.chicken_count;
      totalChickens += sensor.chicken_count;
    }
  });

  const avgWeight = totalChickens > 0 ? totalWeight / totalChickens : 0;

  // Calculate daily gain
  let yesterdayAvgWeight = 0;
  if (yesterdaySummary) {
    let yTotalWeight = 0;
    let yTotalChickens = 0;

    yesterdaySummary.data.forEach((sensor) => {
      if (sensor.avg_weight_actual > 0 && sensor.chicken_count > 0) {
        yTotalWeight += sensor.avg_weight_actual * sensor.chicken_count;
        yTotalChickens += sensor.chicken_count;
      }
    });

    yesterdayAvgWeight = yTotalChickens > 0 ? yTotalWeight / yTotalChickens : 0;
  }

  const dailyGain = yesterdayAvgWeight > 0 ? avgWeight - yesterdayAvgWeight : 0;

  // Calculate uniformity (CV - Coefficient of Variation)
  // Lower CV means better uniformity
  const deviceWeights = summaryData.data
    .filter((s) => s.avg_weight_actual > 0 && s.chicken_count > 0)
    .map((s) => s.avg_weight_actual);

  const mean = avgWeight;
  const variance =
    deviceWeights.length > 0
      ? deviceWeights.reduce((sum, w) => sum + Math.pow(w - mean, 2), 0) / deviceWeights.length
      : 0;
  const stdDev = Math.sqrt(variance);
  const cv = mean > 0 ? (stdDev / mean) * 100 : 0;
  const uniformity = Math.max(0, Math.min(100, 100 - cv)); // Convert CV to uniformity score

  // Determine status
  const getAdgStatus = (adg: number): 'ok' | 'warning' | 'critical' => {
    if (adg >= 60) return 'ok';
    if (adg >= 40) return 'warning';
    return 'critical';
  };

  const getUniformityStatus = (uniformity: number): 'ok' | 'warning' | 'critical' => {
    if (uniformity >= 85) return 'ok';
    if (uniformity >= 75) return 'warning';
    return 'critical';
  };

  return {
    averageWeight: {
      value: Math.round(avgWeight),
      unit: 'g',
      status: 'ok', // Will be updated with actual target comparison
    },
    avgDailyGain: {
      value: Math.round(dailyGain),
      unit: 'g/hari',
      status: getAdgStatus(dailyGain),
    },
    uniformity: {
      value: Math.round(uniformity),
      unit: '%',
      status: getUniformityStatus(uniformity),
    },
  };
}