"""Geocoding integration using Google Maps API (primary) and Goong Map API (fallback)."""
import aiohttp
import re
import unicodedata
from typing import Optional, Tuple, Dict, Any, List
from ..core.coordinates import DroneKnowledgeBase


class GeocodingService:
    """Service for converting location names to coordinates using Google Maps and Goong APIs."""

    def __init__(self, google_api_key: str = None, goong_api_key: str = None):
        # Read from env first; fallback to provided args; final fallback to demo keys
        import os
        self.google_api_key = os.getenv('GOOGLE_MAPS_API_KEY') or google_api_key or "AIzaSyAtrPXZxILYkPMKJKxB_XlBK-SvuHTA2rU"
        self.goong_api_key = os.getenv('GOONG_API_KEY') or goong_api_key or "kK951wrH9UZmF2bCnB1WNwaSlHgeuyPzsIoWUBSg"
        self.google_base_url = "https://maps.googleapis.com/maps/api"
        self.goong_base_url = "https://rsapi.goong.io"
        self.knowledge_base = DroneKnowledgeBase()

    async def geocode_location(self, location_query: str) -> Optional[Tuple[float, float]]:
        """Convert location name to coordinates using Google Maps API (primary) and Goong (fallback).

        Args:
            location_query: Location name or address

        Returns:
            Tuple of (latitude, longitude) or None if not found
        """
        try:
            # Extract the actual location name from the query
            location_name = self._extract_location_name(location_query)

            if not location_name:
                return None

            # Try Google Maps API first
            coords = await self._try_google_geocoding(location_name)
            if coords:
                return coords
            
            # Fallback to Goong API
            coords = await self._try_goong_geocoding(location_name)
            if coords:
                return coords
            
            return None
            
        except Exception as e:
            print(f"Geocoding error: {e}")
            return None
    
    async def _try_google_geocoding(self, location_name: str) -> Optional[Tuple[float, float]]:
        """Try geocoding with Google Maps API."""
        try:
            url = f"{self.google_base_url}/geocode/json"
            params = {
                'address': location_name,
                'key': self.google_api_key
            }

            async with aiohttp.ClientSession() as session:
                async with session.get(url, params=params) as response:
                    if response.status == 200:
                        data = await response.json()
                        
                        if data.get('status') == 'OK' and data.get('results'):
                            result = data['results'][0]
                            location = result['geometry']['location']
                            lat, lng = location['lat'], location['lng']
                            
                            # Validate coordinates and return with 6 decimal precision
                            if -90 <= lat <= 90 and -180 <= lng <= 180:
                                return (float(lat), float(lng))
            return None
        except Exception as e:
            print(f"Google geocoding error: {e}")
            return None
    
    async def _try_goong_geocoding(self, location_name: str) -> Optional[Tuple[float, float]]:
        """Try geocoding with Goong API as fallback."""
        try:
            url = f"{self.goong_base_url}/geocode"
            params = {
                'address': location_name,
                'api_key': self.goong_api_key
            }

            async with aiohttp.ClientSession() as session:
                async with session.get(url, params=params) as response:
                    if response.status == 200:
                        data = await response.json()

                        # Goong may return 'status' or 'error'. Prefer results when available
                        results = data.get('results') or []
                        if results:
                            # Choose the highest confidence result if available
                            result = results[0]
                            geometry = result.get('geometry', {})
                            location = geometry.get('location', {})

                            lat = location.get('lat')
                            lng = location.get('lng')

                            if lat is not None and lng is not None:
                                return (float(lat), float(lng))

            return None
        except Exception as e:
            print(f"Goong geocoding error: {e}")
            return None

    def _extract_location_name(self, query: str) -> Optional[str]:
        """Extract location name from user query."""
        # Common patterns for location queries
        patterns = [
            r'around\s+(.+)',
            r'near\s+(.+)',
            r'at\s+(.+)',
            r'in\s+(.+)',
            r'from\s+(.+)',
            r'scan\s+\d*\s*m\s+around\s+(.+)',
            r'scan\s+around\s+(.+)',
            r'help me scan\s+\d*\s*m\s+around\s+(.+)',
            r'(.+)\s+district',
            r'(.+)\s+province',
            r'(.+)\s+city',
            r'(.+)\s+quận',
            r'(.+)\s+tỉnh',
            r'(.+)\s+thành phố'
        ]

        query_lower = self._normalize_text(query.lower())

        for pattern in patterns:
            match = re.search(pattern, query_lower)
            if match:
                location = match.group(1).strip()
                # Remove common words that might interfere
                location = re.sub(r'\b(the|a|an|my|your|our)\b', '', location).strip()
                return location

        # If no pattern matches, try to extract meaningful location words
        words = query_lower.split()
        if len(words) >= 2:
            # Look for Vietnamese place names
            vietnamese_locations = ['da nang', 'hai chau', 'son tra', 'ngu hanh son', 'lien chieu', 'hoi an', 'hue', 'quang nam']

            # Check for multi-word Vietnamese locations
            for vietnamese_place in vietnamese_locations:
                if vietnamese_place in query_lower:
                    return vietnamese_place

            # Return the last meaningful words (likely the location)
            meaningful_words = [word for word in words if len(word) > 2 and word not in ['help', 'scan', 'me', 'around', 'near', 'at', 'in']]
            if meaningful_words:
                return ' '.join(meaningful_words[-3:])  # Take last 3 meaningful words

        return query.strip()

    def _normalize_text(self, text: str) -> str:
        """Normalize Vietnamese diacritics to ASCII for better matching."""
        nfkd = unicodedata.normalize('NFD', text)
        return ''.join(c for c in nfkd if not unicodedata.combining(c))

    async def parse_location_with_distance(self, query: str) -> Optional[Dict[str, Any]]:
        """Parse location query that includes distance information.

        Args:
            query: User query like "scan 100m around Hải Châu"

        Returns:
            Dict with location_name, distance_meters, and coordinates
        """
        try:
            # Extract distance
            distance_match = re.search(r'(\d+)\s*m', query)
            distance = int(distance_match.group(1)) if distance_match else 100

            # Extract location
            location_name = self._extract_location_name(query)

            if location_name:
                # Geocode the location
                coordinates = await self.geocode_location(location_name)

                if coordinates:
                    return {
                        'location_name': location_name,
                        'distance_meters': distance,
                        'coordinates': coordinates,
                        'center_lat': coordinates[0],
                        'center_lon': coordinates[1]
                    }

            return None

        except Exception as e:
            print(f"Error parsing location with distance: {e}")
            return None

    async def create_mission_from_location_query(self, query: str) -> Optional[Dict[str, Any]]:
        """Create mission parameters from location-based query.

        Args:
            query: User query like "scan 100m around Hải Châu"

        Returns:
            Mission parameters dict or None if parsing failed
        """
        result = await self.parse_location_with_distance(query)

        if result:
            # Calculate mission area based on distance
            center_lat, center_lon = result['coordinates']
            distance = result['distance_meters']

            # Create scaled survey grid to avoid overlapping waypoints for small areas
            waypoints = self._create_scaled_survey(center_lat, center_lon, altitude=80, requested_distance=distance)

            return {
                'mission_type': 'survey',
                'location_name': result['location_name'],
                'coordinates': result['coordinates'],
                'distance_meters': result['distance_meters'],
                'altitude': 80,
                'waypoints': waypoints,
                'waypoint_count': len(waypoints)
            }

        return None

    async def _autocomplete_then_detail(self, input_text: str) -> Optional[Tuple[float, float]]:
        """Use Goong Autocomplete + Place Detail to resolve precise coordinates."""
        try:
            ac_url = f"{self.base_url}/Place/AutoComplete"
            params = {'input': input_text, 'api_key': self.api_key}
            async with aiohttp.ClientSession() as session:
                async with session.get(ac_url, params=params) as resp:
                    if resp.status != 200:
                        return None
                    ac_data = await resp.json()
                    predictions: List[Dict[str, Any]] = ac_data.get('predictions') or []
                    if not predictions:
                        return None
                    place_id = predictions[0].get('place_id') or predictions[0].get('placeId')
                    if not place_id:
                        return None

            detail_url = f"{self.base_url}/Place/Detail"
            dparams = {'place_id': place_id, 'api_key': self.api_key}
            async with aiohttp.ClientSession() as session:
                async with session.get(detail_url, params=dparams) as resp:
                    if resp.status != 200:
                        return None
                    ddata = await resp.json()
                    result = ddata.get('result') or {}
                    geometry = result.get('geometry', {})
                    location = geometry.get('location', {})
                    lat = location.get('lat')
                    lng = location.get('lng')
                    if lat is not None and lng is not None:
                        return (float(lat), float(lng))
            return None
        except Exception:
            return None

    def _create_scaled_survey(self, center_lat: float, center_lon: float, altitude: int, requested_distance: int) -> List[Dict[str, Any]]:
        """Create a survey grid with spacing scaled to requested distance (prevents overlapping waypoints)."""
        waypoints: List[Dict[str, Any]] = []
        grid_size = 4
        # scale spacing: for 100m request → ~35m spacing; clamp between 20 and 150m
        spacing = max(20, min(150, int(max(50, requested_distance) / (grid_size - 1))))
        for i in range(grid_size):
            for j in range(grid_size):
                north_offset = (i - grid_size/2) * spacing
                east_offset = (j - grid_size/2) * spacing
                wp_lat, _ = self.knowledge_base.calculate_coordinate_offset(center_lat, center_lon, north_offset, 'north')
                wp_lat, wp_lon = self.knowledge_base.calculate_coordinate_offset(wp_lat, center_lon, east_offset, 'east')
                waypoints.append({'lat': wp_lat, 'lon': wp_lon, 'altitude': altitude, 'hold_time': 1.0, 'accept_radius': 3.0})
        return waypoints