# processing/vector_store.py
"""
Main vector store interface that supports all three database options
Unified API for ChromaDB, FAISS, and Pinecone
"""

from typing import List, Dict, Any, Optional, Union
from processing.chroma_manager import ChromaManager
from processing.faiss_manager import FaissManager
from processing.pinecone_manager import PineconeManager
from config.vector_config import get_vector_config, get_available_vector_types


class VectorStore:
    """
    Unified vector store interface supporting multiple database backends
    """

    def __init__(self, vector_type: str = "chromadb", **kwargs):
        self.vector_type = vector_type
        self.manager = None
        self._initialize_manager(vector_type, kwargs)

    def _initialize_manager(self, vector_type: str, config: Dict[str, Any]):
        """Initialize the appropriate vector database manager"""
        try:
            if vector_type == "chromadb":
                self.manager = ChromaManager(**config)
            elif vector_type == "faiss_sqlite":
                self.manager = FaissManager(**config)
            elif vector_type == "pinecone":
                self.manager = PineconeManager(**config)
            else:
                raise ValueError(f"Unknown vector type: {vector_type}")

            print(f"✅ Vector store initialized: {vector_type}")

        except Exception as e:
            print(f"❌ Error initializing {vector_type} manager: {e}")
            # Fallback to ChromaDB
            if vector_type != "chromadb":
                print("🔄 Falling back to ChromaDB...")
                self.vector_type = "chromadb"
                self._initialize_manager("chromadb", config)

    def add_papers(self, papers: List[Dict[str, Any]], **kwargs) -> bool:
        """Add papers to vector store"""
        if not self.manager:
            print("❌ Vector store not initialized")
            return False

        return self.manager.add_papers(papers, **kwargs)

    def search(self, query: str, **kwargs) -> List[Dict[str, Any]]:
        """Search for similar paper chunks"""
        if not self.manager:
            print("❌ Vector store not initialized")
            return []

        return self.manager.search(query, **kwargs)

    def get_stats(self) -> Dict[str, Any]:
        """Get statistics about the vector store"""
        if not self.manager:
            return {"error": "Vector store not initialized"}

        stats = self.manager.get_collection_stats()
        stats["vector_type"] = self.vector_type
        return stats

    def delete_paper(self, paper_id: str) -> bool:
        """Delete a paper from vector store"""
        if not self.manager:
            print("❌ Vector store not initialized")
            return False

        return self.manager.delete_paper(paper_id)

    def switch_vector_store(self, new_vector_type: str, **kwargs) -> bool:
        """Switch to a different vector store backend"""
        try:
            print(f"🔄 Switching vector store from {self.vector_type} to {new_vector_type}")

            # Initialize new manager
            old_manager = self.manager
            self.manager = None
            self.vector_type = new_vector_type
            self._initialize_manager(new_vector_type, kwargs)

            if self.manager:
                print(f"✅ Successfully switched to {new_vector_type}")
                return True
            else:
                # Restore old manager if switch failed
                self.manager = old_manager
                self.vector_type = getattr(old_manager, 'vector_type', self.vector_type)
                print(f"❌ Failed to switch to {new_vector_type}, restored previous manager")
                return False

        except Exception as e:
            print(f"❌ Error switching vector store: {e}")
            return False


class MultiVectorStore:
    """
    Manager for multiple vector stores running simultaneously
    Useful for performance comparison and redundancy
    """

    def __init__(self):
        self.stores = {}
        self.active_store = None

    def add_store(self, name: str, vector_type: str, **kwargs) -> bool:
        """Add a vector store instance"""
        try:
            store = VectorStore(vector_type, **kwargs)
            self.stores[name] = store

            if not self.active_store:
                self.active_store = name

            print(f"✅ Added vector store: {name} ({vector_type})")
            return True

        except Exception as e:
            print(f"❌ Error adding vector store {name}: {e}")
            return False

    def set_active_store(self, name: str) -> bool:
        """Set the active vector store"""
        if name in self.stores:
            self.active_store = name
            print(f"✅ Active vector store set to: {name}")
            return True
        else:
            print(f"❌ Vector store {name} not found")
            return False

    def get_active_store(self) -> Optional[VectorStore]:
        """Get the active vector store"""
        if self.active_store and self.active_store in self.stores:
            return self.stores[self.active_store]
        return None

    def add_papers_to_all(self, papers: List[Dict[str, Any]]) -> Dict[str, bool]:
        """Add papers to all vector stores"""
        results = {}
        for name, store in self.stores.items():
            try:
                results[name] = store.add_papers(papers)
            except Exception as e:
                print(f"❌ Error adding papers to {name}: {e}")
                results[name] = False
        return results

    def search_all(self, query: str, **kwargs) -> Dict[str, List[Dict[str, Any]]]:
        """Search all vector stores and compare results"""
        results = {}
        for name, store in self.stores.items():
            try:
                results[name] = store.search(query, **kwargs)
            except Exception as e:
                print(f"❌ Error searching {name}: {e}")
                results[name] = []
        return results

    def compare_performance(self, query: str, n_searches: int = 5) -> Dict[str, Any]:
        """Compare performance of all vector stores"""
        import time

        results = {}
        test_query = query or "machine learning medical imaging"

        for name, store in self.stores.items():
            try:
                search_times = []
                for i in range(n_searches):
                    start_time = time.time()
                    store.search(test_query, n_results=10)
                    search_times.append(time.time() - start_time)

                avg_time = sum(search_times) / len(search_times)
                stats = store.get_stats()

                results[name] = {
                    'average_search_time': avg_time,
                    'total_chunks': stats.get('total_chunks', 0),
                    'vector_type': store.vector_type,
                    'search_times': search_times
                }

            except Exception as e:
                print(f"❌ Error testing {name}: {e}")
                results[name] = {'error': str(e)}

        return results


# Quick test and comparison
def test_all_vector_stores():
    """Test and compare all vector store options"""
    test_papers = [
        {
            'id': 'comparison_test_001',
            'title': 'Vector Store Comparison Test',
            'abstract': 'This paper tests different vector database implementations for medical research applications.',
            'source': 'test',
            'domain': 'medical_imaging',
            'authors': ['Test Researcher']
        }
    ]

    print("🧪 Testing All Vector Stores")
    print("=" * 60)

    multi_store = MultiVectorStore()

    # Test ChromaDB
    print("\n🔬 Testing ChromaDB...")
    chroma_success = multi_store.add_store(
        "chromadb_test",
        "chromadb",
        persist_directory="./data/test_comparison/chromadb"
    )

    # Test FAISS
    print("\n🔬 Testing FAISS...")
    faiss_success = multi_store.add_store(
        "faiss_test",
        "faiss_sqlite",
        faiss_index_path="./data/test_comparison/faiss/index.faiss",
        sqlite_db_path="./data/test_comparison/faiss/metadata.db",
        index_type="Flat"
    )

    # Note: Pinecone requires API key, so we'll skip for basic test
    print("\n🔬 Pinecone test skipped (requires API key)")

    # Add papers to successful stores
    successful_stores = []
    if chroma_success:
        successful_stores.append("chromadb_test")
    if faiss_success:
        successful_stores.append("faiss_test")

    if successful_stores:
        print(f"\n📦 Adding test papers to: {', '.join(successful_stores)}")
        add_results = multi_store.add_papers_to_all(test_papers)

        # Test search
        print(f"\n🔍 Testing search across all stores...")
        search_results = multi_store.search_all("vector database medical research")

        for store_name, results in search_results.items():
            print(f"   {store_name}: {len(results)} results")

        # Compare performance
        print(f"\n⚡ Performance comparison...")
        performance = multi_store.compare_performance("vector database", n_searches=3)

        for store_name, perf_data in performance.items():
            if 'error' not in perf_data:
                print(
                    f"   {store_name}: {perf_data['average_search_time']:.3f}s avg, {perf_data['total_chunks']} chunks")

    print(f"\n✅ Vector store testing completed!")


if __name__ == "__main__":
    test_all_vector_stores()