app/mcp/tools/graph_tool.py

"""Graph Tool - Neo4j spatial search with place details, relationships, and OSM geocoding.

Features:
- Spatial search (find nearby places by coordinates)
- Place details with photos and reviews
- Same category relationships
- OpenStreetMap geocoding fallback
"""

from dataclasses import dataclass, field
from typing import Optional, Any

import httpx

from app.shared.integrations.neo4j_client import neo4j_client


@dataclass
class PlaceResult:
    """Result from nearby places search."""

    place_id: str
    name: str
    category: str
    lat: float
    lng: float
    distance_km: float | None = None
    rating: float | None = None
    description: str | None = None


@dataclass
class NearbyPlace:
    """Nearby place with distance."""

    place_id: str
    name: str
    category: str
    rating: float
    distance_km: float


@dataclass
class Review:
    """Place review."""

    text: str
    rating: int
    reviewer: str


@dataclass
class PlaceDetails:
    """Complete place details from Neo4j."""

    place_id: str
    name: str
    category: str
    rating: float
    address: str
    phone: str | None = None
    website: str | None = None
    google_maps_url: str | None = None
    description: str | None = None
    specialty: str | None = None
    price_range: str | None = None
    coordinates: dict[str, float] = field(default_factory=dict)
    photos_count: int = 0
    reviews_count: int = 0
    photos: list[str] = field(default_factory=list)
    reviews: list[Review] = field(default_factory=list)
    nearby_places: list[NearbyPlace] = field(default_factory=list)
    same_category: list[dict[str, Any]] = field(default_factory=list)


# Available categories in Neo4j - imported from centralized prompts
from app.shared.prompts import AVAILABLE_CATEGORIES


# Tool definition for agent - imported from centralized prompts
from app.shared.prompts import FIND_NEARBY_PLACES_TOOL as TOOL_DEFINITION


async def find_nearby_places(
    lat: float,
    lng: float,
    max_distance_km: float = 5.0,
    category: str | None = None,
    limit: int = 10,
) -> list[PlaceResult]:
    """
    Find nearby places using Neo4j spatial query.

    Args:
        lat: Center latitude
        lng: Center longitude
        max_distance_km: Maximum distance in kilometers
        category: Optional category filter
        limit: Maximum results

    Returns:
        List of nearby places ordered by distance
    """
    category_filter = ""
    if category:
        category_filter = "AND toLower(p.category) CONTAINS toLower($category)"

    query = f"""
    MATCH (p:Place)
    WITH p, point.distance(
        point({{latitude: p.latitude, longitude: p.longitude}}),
        point({{latitude: $lat, longitude: $lng}})
    ) / 1000 as distance_km
    WHERE distance_km <= $max_distance {category_filter}
    RETURN 
        p.id as place_id,
        p.name as name,
        p.category as category,
        p.latitude as lat,
        p.longitude as lng,
        distance_km,
        p.rating as rating,
        p.description as description
    ORDER BY distance_km
    LIMIT $limit
    """

    params = {
        "lat": lat,
        "lng": lng,
        "max_distance": max_distance_km,
        "limit": limit,
    }
    if category:
        params["category"] = category

    results = await neo4j_client.run_cypher(query, params)

    return [
        PlaceResult(
            place_id=r["place_id"],
            name=r["name"],
            category=r["category"] or '',
            lat=r["lat"] or 0.0,
            lng=r["lng"] or 0.0,
            distance_km=r.get("distance_km"),
            rating=r.get("rating"),
            description=r.get("description"),
        )
        for r in results
    ]


async def get_place_details(
    place_id: str,
    include_nearby: bool = True,
    include_same_category: bool = True,
    nearby_limit: int = 5,
) -> PlaceDetails | None:
    """
    Get complete place details including photos, reviews, and relationships.

    Args:
        place_id: The place identifier
        include_nearby: Whether to include nearby places
        include_same_category: Whether to include same category places
        nearby_limit: Limit for nearby/related results

    Returns:
        PlaceDetails or None if not found
    """
    # Main place query with photos and reviews
    query = """
    MATCH (p:Place {id: $place_id})
    OPTIONAL MATCH (p)-[:HAS_PHOTO]->(photo:Photo)
    OPTIONAL MATCH (p)-[:HAS_REVIEW]->(review:Review)
    RETURN p,
           collect(DISTINCT photo.path) as photos,
           collect(DISTINCT {
               text: review.text,
               rating: review.rating,
               reviewer: review.reviewer
           }) as reviews
    """

    results = await neo4j_client.run_cypher(query, {"place_id": place_id})

    if not results or not results[0].get('p'):
        return None

    record = results[0]
    place = record['p']

    details = PlaceDetails(
        place_id=place.get('id', place_id),
        name=place.get('name', 'Unknown'),
        category=place.get('category', ''),
        rating=float(place.get('rating', 0) or 0),
        address=place.get('address', ''),
        phone=place.get('phone'),
        website=place.get('website'),
        google_maps_url=place.get('google_maps_url'),
        description=place.get('description'),
        specialty=place.get('specialty'),
        price_range=place.get('price_range'),
        coordinates={
            'lat': float(place.get('latitude', 0) or 0),
            'lng': float(place.get('longitude', 0) or 0)
        },
        photos_count=int(place.get('photos_count', 0) or 0),
        reviews_count=int(place.get('reviews_count', 0) or 0),
        photos=record.get('photos', [])[:10],
        reviews=[
            Review(
                text=r['text'] or '',
                rating=int(r['rating'] or 0),
                reviewer=r['reviewer'] or ''
            )
            for r in record.get('reviews', [])[:5]
            if r.get('text')
        ]
    )

    # Get nearby places
    if include_nearby:
        details.nearby_places = await get_nearby_by_relationship(place_id, nearby_limit)

    # Get same category places
    if include_same_category:
        details.same_category = await get_same_category_places(place_id, nearby_limit)

    return details


async def get_nearby_by_relationship(
    place_id: str,
    limit: int = 5,
    max_distance_km: float = 2.0
) -> list[NearbyPlace]:
    """
    Get places near a given place using NEAR relationship.

    Args:
        place_id: The source place identifier
        limit: Maximum number of results
        max_distance_km: Maximum distance in km

    Returns:
        List of NearbyPlace objects
    """
    query = """
    MATCH (p:Place {id: $place_id})-[n:NEAR]-(other:Place)
    WHERE n.distance_km <= $max_distance
    RETURN other.id as place_id,
           other.name as name,
           other.category as category,
           other.rating as rating,
           n.distance_km as distance_km
    ORDER BY n.distance_km
    LIMIT $limit
    """

    results = await neo4j_client.run_cypher(query, {
        "place_id": place_id,
        "max_distance": max_distance_km,
        "limit": limit
    })

    return [
        NearbyPlace(
            place_id=r['place_id'],
            name=r['name'],
            category=r['category'] or '',
            rating=float(r['rating'] or 0),
            distance_km=round(float(r['distance_km'] or 0), 2)
        )
        for r in results
    ]


async def get_same_category_places(
    place_id: str,
    limit: int = 5
) -> list[dict[str, Any]]:
    """
    Get other places in the same category.

    Args:
        place_id: The source place identifier
        limit: Maximum number of results

    Returns:
        List of places in same category, ordered by rating
    """
    query = """
    MATCH (p:Place {id: $place_id})-[:IN_CATEGORY]->(c:Category)<-[:IN_CATEGORY]-(other:Place)
    WHERE other.id <> $place_id
    RETURN other.id as place_id,
           other.name as name,
           other.category as category,
           other.rating as rating,
           other.address as address
    ORDER BY other.rating DESC
    LIMIT $limit
    """

    results = await neo4j_client.run_cypher(query, {
        "place_id": place_id,
        "limit": limit
    })

    return [
        {
            'place_id': r['place_id'],
            'name': r['name'],
            'category': r['category'] or '',
            'rating': float(r['rating'] or 0),
            'address': r['address'] or ''
        }
        for r in results
    ]


async def geocode_location(location_name: str, country: str = "Vietnam") -> tuple[float, float] | None:
    """
    Geocode a location name using OpenStreetMap Nominatim API.

    Args:
        location_name: Name of the place (e.g., "Cầu Rồng", "Bãi biển Mỹ Khê")
        country: Country to bias search (default: Vietnam)

    Returns:
        (lat, lng) tuple or None if not found
    """
    search_query = f"{location_name}, Da Nang, {country}"

    try:
        async with httpx.AsyncClient(timeout=10.0) as client:
            response = await client.get(
                "https://nominatim.openstreetmap.org/search",
                params={
                    "q": search_query,
                    "format": "json",
                    "limit": 1,
                    "addressdetails": 0,
                },
                headers={
                    "User-Agent": "LocalMate-DaNang/1.0 (travel assistant app)",
                },
            )
            response.raise_for_status()
            data = response.json()

            if data and len(data) > 0:
                lat = float(data[0]["lat"])
                lng = float(data[0]["lon"])
                return (lat, lng)

    except Exception:
        pass

    return None


async def get_location_coordinates(location_name: str) -> tuple[float, float] | None:
    """
    Get coordinates for a location name.

    First tries Neo4j, then falls back to OpenStreetMap Nominatim.

    Args:
        location_name: Name of the place (e.g., "Khách sạn Rex", "Cầu Rồng")

    Returns:
        (lat, lng) tuple or None if not found
    """
    # Try Neo4j first
    try:
        query = """
        MATCH (p:Place)
        WHERE toLower(p.name) CONTAINS toLower($name)
        RETURN p.latitude as lat, p.longitude as lng
        LIMIT 1
        """
        results = await neo4j_client.run_cypher(query, {"name": location_name})
        if results and results[0].get("lat") and results[0].get("lng"):
            return (results[0]["lat"], results[0]["lng"])
    except Exception:
        pass

    # Fallback to OpenStreetMap Nominatim
    osm_result = await geocode_location(location_name)
    if osm_result:
        return osm_result

    return None