import chromadb
from typing import List, Dict
import numpy as np
from config import settings

class VectorStore:
    """ChromaDB vector store for resumes and job descriptions"""
    
    def __init__(self):
        """Initialize ChromaDB client with persistent storage."""
        # Use new ChromaDB API (1.4.1+)
        self.client = chromadb.PersistentClient(
            path=settings.CHROMA_PERSIST_DIRECTORY
        )
        
        # Create collections
        self.resume_collection = self.client.get_or_create_collection(
            name="resumes",
            metadata={"description": "Resume embeddings"}
        )
        
        self.job_collection = self.client.get_or_create_collection(
            name="jobs",
            metadata={"description": "Job description embeddings"}
        )
    
    def add_resume_chunks(self, resume_id: int, chunks: List[Dict], embeddings: np.ndarray):
        """Add resume chunks to vector store"""
        ids = [f"resume_{resume_id}_chunk_{i}" for i in range(len(chunks))]
        documents = [chunk['text'] for chunk in chunks]
        metadatas = [
            {
                'resume_id': resume_id,
                'section': chunk['section'],
                'chunk_type': chunk['chunk_type'],
                'position': chunk['position']
            }
            for chunk in chunks
        ]
        
        self.resume_collection.add(
            ids=ids,
            embeddings=embeddings.tolist(),
            documents=documents,
            metadatas=metadatas
        )
    
    def add_job_chunks(self, job_id: int, chunks: List[Dict], embeddings: np.ndarray):
        """Add job description chunks to vector store"""
        ids = [f"job_{job_id}_chunk_{i}" for i in range(len(chunks))]
        documents = [chunk['text'] for chunk in chunks]
        metadatas = [
            {
                'job_id': job_id,
                'section': chunk.get('section', 'description'),
                'position': chunk.get('position', i)
            }
            for i, chunk in enumerate(chunks)
        ]
        
        self.job_collection.add(
            ids=ids,
            embeddings=embeddings.tolist(),
            documents=documents,
            metadatas=metadatas
        )
    
    def search_similar_chunks(self, query_embedding: np.ndarray, collection_name: str = "resumes", 
                             n_results: int = 10, filter_metadata: Dict = None):
        """Search for similar chunks"""
        collection = self.resume_collection if collection_name == "resumes" else self.job_collection
        
        results = collection.query(
            query_embeddings=[query_embedding.tolist()],
            n_results=n_results,
            where=filter_metadata
        )
        
        return results
    
    def get_resume_chunks(self, resume_id: int):
        """Get all chunks for a resume"""
        results = self.resume_collection.get(
            where={"resume_id": resume_id}
        )
        return results
    
    def get_job_chunks(self, job_id: int):
        """Get all chunks for a job"""
        results = self.job_collection.get(
            where={"job_id": job_id}
        )
        return results
    
    def delete_resume_chunks(self, resume_id: int):
        """Delete all chunks for a resume"""
        self.resume_collection.delete(
            where={"resume_id": resume_id}
        )
    
    def delete_job_chunks(self, job_id: int):
        """Delete all chunks for a job"""
        self.job_collection.delete(
            where={"job_id": job_id}
        )