#!/usr/bin/env bun

/**
 * Bay Area COVID-19 Wastewater Status Command
 *
 * Analyzes the Substrate COVID wastewater dataset to report:
 * - Current viral load level
 * - Risk assessment
 * - Trend direction (ascending/descending/stable)
 * - Recent trend analysis
 */

import { readFileSync } from 'fs';
import { join } from 'path';

const DATASET_PATH = join(__dirname, 'Data/Bay-Area-COVID-Wastewater/COVID-Wastewater-California-Statewide-2022-2025.csv');

interface WastewaterData {
  season: string;
  week_ending_date: string;
  sars_cov2_log10_copies_ml: number;
  data_source: string;
  region: string;
  notes: string;
}

function parseCSV(csvContent: string): WastewaterData[] {
  const lines = csvContent.trim().split('\n');
  const headers = lines[0].split(',');

  return lines.slice(1).map(line => {
    const values = line.split(',');
    return {
      season: values[0],
      week_ending_date: values[1],
      sars_cov2_log10_copies_ml: parseFloat(values[2]),
      data_source: values[3],
      region: values[4],
      notes: values[5] || ''
    };
  });
}

function getRiskLevel(value: number): { level: string; color: string } {
  // Risk thresholds based on log10 viral copies/mL
  if (value >= 10) return { level: 'VERY HIGH', color: '🔴' };
  if (value >= 5) return { level: 'HIGH', color: '🟠' };
  if (value >= 3) return { level: 'MODERATE', color: '🟡' };
  if (value >= 2) return { level: 'LOW', color: '🟢' };
  return { level: 'MINIMAL', color: '🔵' };
}

function getTrend(current: number, previous: number, twoWeeksAgo: number): string {
  const recentChange = current - previous;
  const weeklyChange = previous - twoWeeksAgo;

  // Check if consistently moving in one direction
  if (recentChange > 0.3 && weeklyChange > 0.3) return 'RAPIDLY ASCENDING ⬆️⬆️';
  if (recentChange > 0.1) return 'ASCENDING ⬆️';
  if (recentChange < -0.3 && weeklyChange < -0.3) return 'RAPIDLY DESCENDING ⬇️⬇️';
  if (recentChange < -0.1) return 'DESCENDING ⬇️';
  return 'STABLE ➡️';
}

function formatDate(dateStr: string): string {
  const date = new Date(dateStr);
  return date.toLocaleDateString('en-US', {
    month: 'short',
    day: 'numeric',
    year: 'numeric'
  });
}

try {
  const csvContent = readFileSync(DATASET_PATH, 'utf-8');
  const data = parseCSV(csvContent);

  // Sort by date (most recent first)
  data.sort((a, b) => new Date(b.week_ending_date).getTime() - new Date(a.week_ending_date).getTime());

  const latest = data[0];
  const oneWeekAgo = data[1];
  const twoWeeksAgo = data[2];
  const fourWeeksAgo = data[4];

  const risk = getRiskLevel(latest.sars_cov2_log10_copies_ml);
  const trend = getTrend(latest.sars_cov2_log10_copies_ml, oneWeekAgo.sars_cov2_log10_copies_ml, twoWeeksAgo.sars_cov2_log10_copies_ml);

  const weeklyChange = ((latest.sars_cov2_log10_copies_ml - oneWeekAgo.sars_cov2_log10_copies_ml) / oneWeekAgo.sars_cov2_log10_copies_ml * 100).toFixed(1);
  const monthlyChange = ((latest.sars_cov2_log10_copies_ml - fourWeeksAgo.sars_cov2_log10_copies_ml) / fourWeeksAgo.sars_cov2_log10_copies_ml * 100).toFixed(1);

  console.log('\n━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━');
  console.log('🦠 BAY AREA COVID-19 WASTEWATER STATUS');
  console.log('━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━\n');

  console.log(`📅 Latest Data: ${formatDate(latest.week_ending_date)}`);
  console.log(`📊 Viral Load: ${latest.sars_cov2_log10_copies_ml} log10 copies/mL\n`);

  console.log(`${risk.color} Risk Level: ${risk.level}`);
  console.log(`📈 Trend: ${trend}\n`);

  console.log('📉 Recent Changes:');
  console.log(`   Weekly:  ${weeklyChange > 0 ? '+' : ''}${weeklyChange}%`);
  console.log(`   Monthly: ${monthlyChange > 0 ? '+' : ''}${monthlyChange}%\n`);

  console.log('📍 Previous Weeks:');
  console.log(`   ${formatDate(oneWeekAgo.week_ending_date)}: ${oneWeekAgo.sars_cov2_log10_copies_ml}`);
  console.log(`   ${formatDate(twoWeeksAgo.week_ending_date)}: ${twoWeeksAgo.sars_cov2_log10_copies_ml}`);
  console.log(`   ${formatDate(fourWeeksAgo.week_ending_date)}: ${fourWeeksAgo.sars_cov2_log10_copies_ml}\n`);

  console.log('ℹ️  Source: California Department of Public Health');
  console.log('ℹ️  Region: California Statewide (Bay Area proxy)');
  console.log('ℹ️  Leading indicator: ~4-7 days ahead of clinical data\n');
  console.log('━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━\n');

} catch (error) {
  console.error('❌ Error reading COVID wastewater data:', error);
  console.error('\nMake sure the dataset exists at:');
  console.error(DATASET_PATH);
  process.exit(1);
}