/**
 * API Route: Record environment reading
 * PUT /api/vertical-farm/batch/[batchId]/environment
 */

import type { NextApiRequest, NextApiResponse } from 'next';
import { getVerticalFarmController } from '../../../../../lib/vertical-farming/controller';
import { ZoneEnvironmentReadings } from '../../../../../lib/vertical-farming/types';

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse
) {
  if (req.method !== 'PUT') {
    return res.status(405).json({ success: false, error: 'Method not allowed' });
  }

  try {
    const { batchId } = req.query;
    const {
      temperatureC,
      humidityPercent,
      co2Ppm,
      ppfd,
      waterTempC,
      ec,
      ph,
      dissolvedOxygenPpm,
      airflowMs
    } = req.body;

    if (!batchId || typeof batchId !== 'string') {
      return res.status(400).json({
        success: false,
        error: 'Batch ID is required'
      });
    }

    // Validate required readings
    if (temperatureC === undefined || humidityPercent === undefined || ec === undefined || ph === undefined) {
      return res.status(400).json({
        success: false,
        error: 'Missing required fields: temperatureC, humidityPercent, ec, ph'
      });
    }

    const controller = getVerticalFarmController();

    // Access internal state to find the batch
    const state = controller.toJSON() as any;
    const batches = state.batches as [string, any][];
    const batchEntry = batches.find(([id]) => id === batchId);

    if (!batchEntry) {
      return res.status(404).json({
        success: false,
        error: `Batch not found: ${batchId}`
      });
    }

    const batch = batchEntry[1];

    const readings: ZoneEnvironmentReadings = {
      timestamp: new Date().toISOString(),
      temperatureC,
      humidityPercent,
      co2Ppm: co2Ppm || 800,
      vpd: calculateVpd(temperatureC, humidityPercent),
      ppfd: ppfd || 300,
      dli: (ppfd || 300) * 16 * 3600 / 1000000, // Approximate DLI
      waterTempC: waterTempC || 20,
      ec,
      ph,
      dissolvedOxygenPpm: dissolvedOxygenPpm || 8,
      airflowMs: airflowMs || 0.5,
      alerts: []
    };

    const alerts = controller.recordEnvironment(batch.zoneId, readings);

    res.status(200).json({
      success: true,
      data: {
        readings,
        alerts,
        batchId,
        zoneId: batch.zoneId
      }
    });
  } catch (error: any) {
    console.error('Error recording environment:', error);
    res.status(500).json({ success: false, error: error.message || 'Internal server error' });
  }
}

/**
 * Calculate Vapor Pressure Deficit
 */
function calculateVpd(tempC: number, humidityPercent: number): number {
  // Saturation vapor pressure (kPa)
  const svp = 0.6108 * Math.exp((17.27 * tempC) / (tempC + 237.3));
  // Actual vapor pressure
  const avp = svp * (humidityPercent / 100);
  // VPD
  return Math.round((svp - avp) * 100) / 100;
}