import { NextResponse } from 'next/server';

// Library branch locations with approximate coordinates
const LIBRARY_LOCATIONS: Record<string, { lat: number; lng: number }> = {
  'Beckwourth': { lat: 32.7157, lng: -117.1611 },
  'Benjamin': { lat: 32.8328, lng: -117.2713 },
  'Balboa': { lat: 32.7330, lng: -117.1430 },
  'Carmel Mountain': { lat: 32.9286, lng: -117.1311 },
  'Carmel Valley': { lat: 32.9340, lng: -117.2340 },
  'Central Library': { lat: 32.7216, lng: -117.1574 },
  'City Heights': { lat: 32.7411, lng: -117.1045 },
  'Clairemont': { lat: 32.8328, lng: -117.2050 },
  'College-Rolando': { lat: 32.7482, lng: -117.0704 },
  'Kensington': { lat: 32.7644, lng: -117.1164 },
  'La Jolla': { lat: 32.8344, lng: -117.2544 },
  'Linda Vista': { lat: 32.7714, lng: -117.1789 },
  'Logan Heights': { lat: 32.7030, lng: -117.1289 },
  'Malcolm X': { lat: 32.7089, lng: -117.1242 },
  'Mission Hills': { lat: 32.7469, lng: -117.1978 },
  'Oak Park': { lat: 32.7328, lng: -117.1461 },
  'Paradise Hills': { lat: 32.6747, lng: -117.0742 },
  'Rancho Bernardo': { lat: 33.0200, lng: -117.1156 },
  'Rancho Penasquitos': { lat: 32.958034, lng: -117.121975 },
  'San Ysidro': { lat: 32.5592, lng: -117.0431 },
  'Skyline Hills': { lat: 32.6781, lng: -117.0200 },
};

interface BibItem {
  branchName: string;
  availability: {
    statusType: string;
  };
}

interface BiblioResponse {
  entities: {
    bibItems: Record<string, BibItem>;
  };
}

interface LocationData {
  name: string;
  lat: number;
  lng: number;
  available: boolean;
  passType: string;
}

async function fetchAvailabilityData(itemNumber: string): Promise<BibItem[]> {
  try {
    const response = await fetch(
      `https://gateway.bibliocommons.com/v2/libraries/sandiego/bibs/${itemNumber}/availability?locale=en-US`,
      {
        headers: {
          'User-Agent': 'Mozilla/5.0 (compatible; LibraryChecker/1.0)',
        },
      }
    );
    
    if (!response.ok) {
      throw new Error(`HTTP error! status: ${response.status}`);
    }
    
    const data: BiblioResponse = await response.json();
    return Object.values(data.entities.bibItems || {});
  } catch (error) {
    console.error(`Error fetching data for ${itemNumber}:`, error);
    return [];
  }
}

export async function GET() {
  try {
    // Fetch both types of passes
    const [passItems, backpackItems] = await Promise.all([
      fetchAvailabilityData('S161C1690437'), // Pure parking pass
      fetchAvailabilityData('S161C1805116'), // Backpack with pass
    ]);

    const locationMap = new Map<string, LocationData>();

    // Process parking passes
    passItems.forEach(item => {
      const location = LIBRARY_LOCATIONS[item.branchName];
      if (location && item.branchName) {
        const isAvailable = item.availability?.statusType === 'AVAILABLE';
        const existing = locationMap.get(item.branchName);
        
        if (existing) {
          // Update existing entry - if either item type is available, mark as available
          existing.available = existing.available || isAvailable;
          existing.passType = 'Both';
        } else {
          locationMap.set(item.branchName, {
            name: item.branchName,
            lat: location.lat,
            lng: location.lng,
            available: isAvailable,
            passType: 'Pass Only',
          });
        }
      }
    });

    // Process backpack items
    backpackItems.forEach(item => {
      const location = LIBRARY_LOCATIONS[item.branchName];
      if (location && item.branchName) {
        const isAvailable = item.availability?.statusType === 'AVAILABLE';
        const existing = locationMap.get(item.branchName);
        
        if (existing) {
          // Update existing entry - if either item type is available, mark as available
          existing.available = existing.available || isAvailable;
          existing.passType = 'Both';
        } else {
          locationMap.set(item.branchName, {
            name: item.branchName,
            lat: location.lat,
            lng: location.lng,
            available: isAvailable,
            passType: 'Backpack Only',
          });
        }
      }
    });

    const locations = Array.from(locationMap.values());
    
    return NextResponse.json({
      locations,
      lastUpdated: new Date().toISOString(),
    });
  } catch (error) {
    console.error('Error in API route:', error);
    return NextResponse.json(
      { error: 'Failed to fetch availability data' },
      { status: 500 }
    );
  }
}