import os
import json
from typing import Optional
from models import MemoryItem
from datetime import datetime

class KnowledgeBaseBackend:
    """
    Long-term knowledge base (filesystem)
    
    Phase 3: Stub implementation
    Stores docs, roadmaps, and structured knowledge
    """
    
    def __init__(self, kb_path: str = "/data/kb"):
        self.kb_path = kb_path
    
    async def initialize(self):
        """Create KB directory"""
        if not os.path.exists(self.kb_path):
            try:
                os.makedirs(self.kb_path, exist_ok=True)
                print(f"✅ KB directory created: {self.kb_path}")
            except Exception as e:
                print(f"⚠️  Failed to create KB directory: {e}")
                print("   Using in-memory stub")
    
    async def query(
        self,
        agent_id: str,
        query_text: str,
        limit: int = 5
    ) -> list[MemoryItem]:
        """
        Query knowledge base
        
        Phase 3: Returns stub/empty results
        Phase 4: Implement proper KB indexing and search
        """
        # Stub implementation for Phase 3
        print(f"ℹ️  KB query (stub): {query_text[:50]}...")
        
        # Return empty results for now
        # In Phase 4, this would:
        # 1. Index docs/roadmaps with embeddings
        # 2. Perform semantic search
        # 3. Return relevant knowledge chunks
        
        return []
    
    async def store(
        self,
        agent_id: str,
        microdao_id: str,
        kind: str,
        content: dict,
        metadata: Optional[dict] = None
    ) -> str:
        """
        Store knowledge base entry
        
        Phase 3: Stub implementation
        """
        # Stub for Phase 3
        entry_id = f"kb-{datetime.now().timestamp()}"
        print(f"ℹ️  KB store (stub): {entry_id}")
        
        # In Phase 4, would write to filesystem or DB
        # with proper indexing
        
        return entry_id