"""Phase 5 GraphRAG API: 엔티티 중복 제거, 부분그래프 추출, 패턴 매칭, 그래프 분석.

기능:
- 엔티티 중복 감지 및 병합 (벡터 + 텍스트 유사도)
- 의미 기반 부분그래프 추출 (쿼리 임베딩)
- 패턴 매칭 (경로, 순환, SCC)
- 그래프 분석 (중심성, 커뮤니티)
"""

import logging
from typing import Dict, Any, Optional, List

from fastapi import FastAPI, APIRouter, HTTPException, Depends, Query
from fastapi.responses import JSONResponse

from ont_platform.core.graph import (
    EntityResolver,
    RDFToPropertyGraphConverter,
    SubgraphRetriever,
    PatternMatcher,
    GraphAnalytics,
    Neo4jAdapter,
)

logger = logging.getLogger(__name__)

# FastAPI 앱
app = FastAPI(
    title="Ontology Platform - Phase 5 GraphRAG",
    description="엔티티 중복 제거, 부분그래프 추출, 패턴 매칭, 그래프 분석",
    version="0.5.0",
)

# 라우터
graph_router = APIRouter(prefix="/api/v1/graph", tags=["graph"])

# 전역 인스턴스 (싱글톤)
_neo4j_adapter: Optional[Neo4jAdapter] = None


def get_neo4j_adapter() -> Neo4jAdapter:
    """Get or initialize Neo4j adapter."""
    global _neo4j_adapter
    if _neo4j_adapter is None:
        _neo4j_adapter = Neo4jAdapter()
    return _neo4j_adapter


adapter = get_neo4j_adapter()

entity_resolver = EntityResolver()
rdf_converter = RDFToPropertyGraphConverter()
subgraph_retriever = SubgraphRetriever(adapter=adapter)
pattern_matcher = PatternMatcher(adapter=adapter)
graph_analytics = GraphAnalytics(adapter=adapter)


# ============================================================================
# 엔티티 중복 제거 엔드포인트
# ============================================================================


@graph_router.post("/resolve")
async def resolve_duplicates(
    request: Dict[str, Any],
) -> Dict[str, Any]:
    """엔티티 중복 감지 및 병합.

    Args:
        request: JSON body with "entities" field containing list of entities (id, label, type)

    Returns:
        {
            "clusters": [중복 클러스터],
            "report": 리포트,
            "total_duplicates": 감지된 중복 수
        }
    """
    entities = request.get("entities", [])
    try:
        # 임베더 초기화 (필요시)
        if not entity_resolver.embedder:
            await entity_resolver.initialize_embedder()

        # 중복 감지
        clusters = await entity_resolver.detect_duplicates(entities)

        # 리포트 생성
        report = entity_resolver.get_resolution_report(clusters)

        return {
            "status": "success",
            "clusters": [
                {
                    "cluster_id": c.cluster_id,
                    "canonical_id": c.canonical_id,
                    "duplicates": c.duplicates,
                    "confidence": c.confidence,
                    "reason": c.reason,
                }
                for c in clusters
            ],
            "report": report,
            "total_duplicates": report["total_duplicates"],
        }
    except Exception as e:
        logger.error(f"Failed to resolve duplicates: {e}")
        raise HTTPException(status_code=500, detail=str(e))


# ============================================================================
# 부분그래프 추출 엔드포인트
# ============================================================================


@graph_router.post("/subgraph/semantic")
async def retrieve_semantic_context(
    query: str = Query(...),
    top_k: int = Query(10, ge=1, le=100),
    min_similarity: float = Query(0.6, ge=0.0, le=1.0),
    hops: int = Query(1, ge=0, le=3),
) -> Dict[str, Any]:
    """의미 기반 부분그래프 추출 (쿼리 임베딩 유사도).

    Args:
        query: 검색 쿼리 텍스트
        top_k: 상위 K개 매칭 엔티티
        min_similarity: 최소 유사도 임계값 (0-1)
        hops: 확장할 홉 수 (0-3)

    Returns:
        의미 기반 부분그래프
    """
    try:
        # 임베더 초기화 (필요시)
        if not subgraph_retriever.embedder:
            from sentence_transformers import SentenceTransformer
            subgraph_retriever.embedder = SentenceTransformer("all-MiniLM-L6-v2")

        result = await subgraph_retriever.retrieve_by_semantic_query(
            query=query,
            top_k=top_k,
            min_similarity=min_similarity,
            hops=hops,
        )

        return {
            "status": "success",
            "query": query,
            "query_dimension": result.get("query_embedding_dimension", 0),
            "matched_count": result.get("matched_count", 0),
            "matched_entities": result.get("matched_entities", []),
            "nodes": result.get("nodes", []),
            "edges": result.get("edges", []),
        }
    except Exception as e:
        logger.error(f"Failed to retrieve semantic context: {e}")
        raise HTTPException(status_code=500, detail=str(e))


@graph_router.post("/subgraph")
async def extract_subgraph(
    entity_id: int = Query(...),
    hops: int = Query(2, ge=1, le=3),
    min_confidence: float = Query(0.0, ge=0.0, le=1.0),
) -> Dict[str, Any]:
    """N-hop 부분그래프 추출.

    Args:
        entity_id: 중심 엔티티 ID
        hops: 홉 수 (1-3)
        min_confidence: 최소 신뢰도

    Returns:
        부분그래프 정보
    """
    try:
        result = await subgraph_retriever.retrieve_neighborhood(
            entity_id=entity_id,
            hops=hops,
            min_confidence=min_confidence,
        )

        return {
            "status": "success",
            "entity_id": entity_id,
            "hops": hops,
            "subgraph": result,
        }
    except Exception as e:
        logger.error(f"Failed to extract subgraph: {e}")
        raise HTTPException(status_code=500, detail=str(e))


# ============================================================================
# 패턴 매칭 엔드포인트
# ============================================================================


@graph_router.post("/patterns/paths")
async def find_paths(
    start_id: int = Query(...),
    end_id: int = Query(...),
    max_length: int = Query(5, ge=2, le=10),
) -> Dict[str, Any]:
    """두 엔티티 사이의 경로 찾기.

    Args:
        start_id: 시작 엔티티 ID
        end_id: 종료 엔티티 ID
        max_length: 최대 경로 길이

    Returns:
        경로 리스트
    """
    try:
        paths = await pattern_matcher.find_paths(
            start_entity_id=start_id,
            end_entity_id=end_id,
            max_length=max_length,
        )

        return {
            "status": "success",
            "start_id": start_id,
            "end_id": end_id,
            "paths_found": len(paths),
            "paths": [
                {
                    "path": p.path if hasattr(p, "path") else [],
                    "length": p.length if hasattr(p, "length") else 0,
                    "confidence": p.confidence if hasattr(p, "confidence") else 0,
                }
                for p in paths
            ] if paths else [],
        }
    except Exception as e:
        logger.error(f"Failed to find paths: {e}")
        raise HTTPException(status_code=500, detail=str(e))


@graph_router.post("/patterns/cycles")
async def find_cycles() -> Dict[str, Any]:
    """순환 경로 감지.

    Returns:
        순환 리스트
    """
    try:
        cycles = await pattern_matcher.find_cycles()

        return {
            "status": "success",
            "cycles_found": len(cycles),
            "cycles": cycles,
        }
    except Exception as e:
        logger.error(f"Failed to find cycles: {e}")
        raise HTTPException(status_code=500, detail=str(e))


# ============================================================================
# 그래프 분석 엔드포인트
# ============================================================================


@graph_router.post("/analytics/centrality")
async def analyze_centrality(
    centrality_type: str = Query("pagerank", pattern="^(degree|betweenness|closeness|pagerank)$"),
    top_n: int = Query(10, ge=1, le=100),
) -> Dict[str, Any]:
    """엔티티 중심성 분석.

    Args:
        centrality_type: 중심성 타입
        top_n: 상위 N개 반환

    Returns:
        중심성 결과
    """
    try:
        results = await graph_analytics.calculate_centrality(
            centrality_type=centrality_type,
        )

        # 상위 N개만 반환
        top_results = sorted(results, key=lambda x: x.get("score", 0), reverse=True)[
            :top_n
        ]

        return {
            "status": "success",
            "centrality_type": centrality_type,
            "total_entities": len(results),
            "top_n": top_n,
            "results": top_results,
        }
    except Exception as e:
        logger.error(f"Failed to analyze centrality: {e}")
        raise HTTPException(status_code=500, detail=str(e))


@graph_router.post("/analytics/communities")
async def detect_communities(
    algorithm: str = Query("louvain", pattern="^(louvain|leiden)$"),
) -> Dict[str, Any]:
    """커뮤니티 감지.

    Args:
        algorithm: 알고리즘 (louvain, leiden)

    Returns:
        커뮤니티 결과
    """
    try:
        communities = await graph_analytics.detect_communities(algorithm=algorithm)

        return {
            "status": "success",
            "algorithm": algorithm,
            "communities_found": len(communities),
            "communities": [
                {
                    "community_id": c.community_id if hasattr(c, "community_id") else "",
                    "size": c.size if hasattr(c, "size") else 0,
                    "density": c.density if hasattr(c, "density") else 0,
                }
                for c in communities
            ],
        }
    except Exception as e:
        logger.error(f"Failed to detect communities: {e}")
        raise HTTPException(status_code=500, detail=str(e))


# ============================================================================
# 헬스 체크
# ============================================================================


@app.get("/health")
async def health_check() -> Dict[str, Any]:
    """헬스 체크."""
    return {
        "status": "healthy",
        "version": "0.5.0",
        "phase": "5 (GraphRAG)",
        "components": {
            "entity_resolver": "ok",
            "rdf_converter": "ok",
            "subgraph_retriever": "ok",
            "pattern_matcher": "ok",
            "graph_analytics": "ok",
        },
    }


@app.get("/info")
async def get_platform_info() -> Dict[str, Any]:
    """플랫폼 정보."""
    return {
        "platform": "Ontology System Construction Platform",
        "phase": "5 (GraphRAG)",
        "version": "0.5.0",
        "features": {
            "entity_resolution": True,
            "subgraph_retrieval": True,
            "pattern_matching": True,
            "graph_analytics": True,
        },
    }


# ============================================================================
# 라우터 등록
# ============================================================================

app.include_router(graph_router)


if __name__ == "__main__":
    import uvicorn

    uvicorn.run(app, host="0.0.0.0", port=8003)