#!/usr/bin/env python3
"""
Geocode missing Bulgarian institutions using Nominatim API.

Uses OpenStreetMap Nominatim API to find coordinates for Bulgarian cities
that were not found in the GeoNames database.

Rate limit: 1 request per second (Nominatim usage policy)
"""

import sys
import yaml
import time
import requests
from pathlib import Path
from typing import Optional, Dict, Any
from datetime import datetime, timezone

# Add project root to path
project_root = Path(__file__).parent.parent
sys.path.insert(0, str(project_root))

# Configuration
INPUT_FILE = project_root / "data/instances/bulgaria_isil_libraries.yaml"
OUTPUT_FILE = project_root / "data/instances/bulgaria_isil_libraries.yaml"
NOMINATIM_URL = "https://nominatim.openstreetmap.org/search"
USER_AGENT = "GLAM-DataExtraction/1.0 (heritage-data-extraction)"


def geocode_nominatim(city_name: str, country: str = "Bulgaria") -> Optional[Dict[str, Any]]:
    """
    Geocode a city using Nominatim API.
    
    Args:
        city_name: Name of the city (can be Cyrillic)
        country: Country name (default: Bulgaria)
        
    Returns:
        Dict with latitude, longitude, display_name, or None if not found
    """
    params = {
        'q': f"{city_name}, {country}",
        'format': 'json',
        'limit': 1,
        'addressdetails': 1
    }
    
    headers = {
        'User-Agent': USER_AGENT
    }
    
    try:
        response = requests.get(NOMINATIM_URL, params=params, headers=headers)
        response.raise_for_status()
        
        results = response.json()
        
        if results:
            result = results[0]
            return {
                'latitude': float(result['lat']),
                'longitude': float(result['lon']),
                'display_name': result['display_name'],
                'osm_type': result.get('osm_type'),
                'osm_id': result.get('osm_id')
            }
        else:
            return None
            
    except Exception as e:
        print(f"  ⚠️  Error geocoding {city_name}: {e}")
        return None


def main():
    """Main geocoding workflow."""
    print("=" * 80)
    print("Bulgarian ISIL Registry - Geocoding Missing Institutions")
    print("=" * 80)
    print()
    
    # Load institutions
    print(f"Loading institutions from {INPUT_FILE}...")
    with open(INPUT_FILE, 'r', encoding='utf-8') as f:
        content = f.read()
        
        # Extract YAML header comments
        yaml_start = content.index('\n- id:')
        header = content[:yaml_start]
        
        institutions = yaml.safe_load(content[yaml_start:])
    
    print(f"Loaded {len(institutions)} institutions")
    print()
    
    # Find institutions without geocoding
    missing_geocoding = []
    
    for inst in institutions:
        if inst.get('locations'):
            loc = inst['locations'][0]
            if not loc.get('latitude') or not loc.get('longitude'):
                missing_geocoding.append({
                    'index': institutions.index(inst),
                    'isil': inst['identifiers'][0]['identifier_value'],
                    'name': inst['name'],
                    'city': loc.get('city', 'N/A'),
                    'institution': inst
                })
    
    print(f"Institutions missing geocoding: {len(missing_geocoding)}")
    print()
    
    if len(missing_geocoding) == 0:
        print("✓ All institutions already geocoded!")
        return
    
    # Geocode missing institutions
    print("Geocoding institutions using Nominatim API...")
    print("(Rate limited to 1 request per second)")
    print("=" * 80)
    print()
    
    geocoded_count = 0
    failed_count = 0
    
    for i, item in enumerate(missing_geocoding, 1):
        city = item['city']
        isil = item['isil']
        
        print(f"{i:2d}/{len(missing_geocoding)} | {isil} | {city:30s} ", end='', flush=True)
        
        # Try geocoding
        result = geocode_nominatim(city)
        
        if result:
            # Update institution location
            idx = item['index']
            institutions[idx]['locations'][0]['latitude'] = result['latitude']
            institutions[idx]['locations'][0]['longitude'] = result['longitude']
            
            print(f"✓ ({result['latitude']:.5f}, {result['longitude']:.5f})")
            geocoded_count += 1
        else:
            print("✗ Not found")
            failed_count += 1
        
        # Rate limit: 1 request per second (Nominatim usage policy)
        if i < len(missing_geocoding):
            time.sleep(1)
    
    print()
    print("=" * 80)
    print(f"✓ Geocoding complete:")
    print(f"  Successfully geocoded: {geocoded_count}")
    print(f"  Failed to geocode:     {failed_count}")
    print(f"  Total geocoded:        {len(institutions) - failed_count}/{len(institutions)} ({(len(institutions) - failed_count)/len(institutions)*100:.1f}%)")
    print()
    
    # Export updated data
    if geocoded_count > 0:
        print(f"Exporting updated data to {OUTPUT_FILE}...")
        
        # Update header timestamp
        header_lines = header.split('\n')
        for i, line in enumerate(header_lines):
            if line.startswith('# Generated:'):
                header_lines[i] = f'# Generated: {datetime.now(timezone.utc).isoformat()}'
        
        updated_header = '\n'.join(header_lines)
        
        with open(OUTPUT_FILE, 'w', encoding='utf-8') as f:
            f.write(updated_header)
            yaml.dump(institutions, f, allow_unicode=True, default_flow_style=False, sort_keys=False)
        
        print(f"✓ Exported {len(institutions)} institutions")
        print()
    
    # Show failed institutions
    if failed_count > 0:
        print("=" * 80)
        print("⚠️  Institutions that could not be geocoded:")
        print("=" * 80)
        print()
        
        for item in missing_geocoding:
            city = item['city']
            isil = item['isil']
            
            # Check if it was geocoded
            idx = item['index']
            if not institutions[idx]['locations'][0].get('latitude'):
                print(f"  {isil} | {city:30s} | {item['name'][:50]}")
        
        print()
        print("Note: These may be:")
        print("  - Very small villages not in OpenStreetMap")
        print("  - Transliteration issues (Cyrillic → Latin)")
        print("  - Misspellings in source data")
        print()
        print("Manual geocoding may be required for these institutions.")
        print()
    
    print("=" * 80)
    print("✓ Geocoding workflow complete!")
    print("=" * 80)


if __name__ == '__main__':
    main()