"""
B2B Shopping AI Assistant - Main Application Entry
"""
from contextlib import asynccontextmanager
from typing import Any

from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
from pydantic import BaseModel

from config import settings
from webhooks.chatwoot_webhook import router as webhook_router
from utils.logger import setup_logging, get_logger
from utils.cache import get_cache_manager
from integrations.chatwoot import get_chatwoot_client


# Setup logging
setup_logging(settings.log_level)
logger = get_logger(__name__)


# ============ Lifespan Management ============

@asynccontextmanager
async def lifespan(app: FastAPI):
    """Application lifespan manager"""
    # Startup
    logger.info("Starting B2B Shopping AI Assistant")
    
    # Initialize cache connection
    cache = get_cache_manager()
    await cache.connect()
    logger.info("Redis cache connected")
    
    yield
    
    # Shutdown
    logger.info("Shutting down B2B Shopping AI Assistant")
    
    # Close connections
    await cache.disconnect()
    
    chatwoot = get_chatwoot_client()
    await chatwoot.close()
    
    logger.info("Connections closed")


# ============ Application Setup ============

app = FastAPI(
    title="B2B Shopping AI Assistant",
    description="AI-powered customer service assistant with LangGraph and MCP",
    version="1.0.0",
    lifespan=lifespan
)

# CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # Configure appropriately for production
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)


# ============ Exception Handlers ============

@app.exception_handler(Exception)
async def global_exception_handler(request: Request, exc: Exception):
    """Global exception handler"""
    logger.error(
        "Unhandled exception",
        path=request.url.path,
        error=str(exc)
    )
    return JSONResponse(
        status_code=500,
        content={"detail": "Internal server error"}
    )


# ============ Include Routers ============

app.include_router(webhook_router)


# ============ API Endpoints ============

@app.get("/health")
async def health_check():
    """Health check endpoint"""
    return {
        "status": "healthy",
        "service": "b2b-ai-assistant",
        "version": "1.0.0"
    }


@app.get("/")
async def root():
    """Root endpoint"""
    return {
        "name": "B2B Shopping AI Assistant",
        "version": "1.0.0",
        "status": "running"
    }


class QueryRequest(BaseModel):
    """Direct query request model"""
    conversation_id: str
    user_id: str
    account_id: str
    message: str


class QueryResponse(BaseModel):
    """Query response model"""
    response: str
    intent: str | None = None
    requires_human: bool = False
    context: dict[str, Any] = {}


@app.post("/api/agent/query", response_model=QueryResponse)
async def agent_query(request: QueryRequest):
    """Direct agent query endpoint
    
    Allows direct testing of the agent without Chatwoot integration.
    """
    from core.graph import process_message
    
    logger.info(
        "Direct query received",
        conversation_id=request.conversation_id,
        user_id=request.user_id
    )
    
    # Load context from cache
    cache = get_cache_manager()
    context = await cache.get_context(request.conversation_id)
    history = await cache.get_messages(request.conversation_id)
    
    # Process message
    final_state = await process_message(
        conversation_id=request.conversation_id,
        user_id=request.user_id,
        account_id=request.account_id,
        message=request.message,
        history=history,
        context=context
    )
    
    # Update cache
    await cache.add_message(request.conversation_id, "user", request.message)
    if final_state.get("response"):
        await cache.add_message(
            request.conversation_id,
            "assistant",
            final_state["response"]
        )
    
    # Save context
    new_context = final_state.get("context", {})
    new_context["last_intent"] = final_state.get("intent")
    await cache.set_context(request.conversation_id, new_context)
    
    return QueryResponse(
        response=final_state.get("response", ""),
        intent=final_state.get("intent"),
        requires_human=final_state.get("requires_human", False),
        context=final_state.get("context", {})
    )


@app.get("/api/config")
async def get_config():
    """Get sanitized configuration"""
    return {
        "zhipu_model": settings.zhipu_model,
        "max_conversation_steps": settings.max_conversation_steps,
        "conversation_timeout": settings.conversation_timeout,
        "mcp_servers": {
            "strapi": settings.strapi_mcp_url,
            "order": settings.order_mcp_url,
            "aftersale": settings.aftersale_mcp_url,
            "product": settings.product_mcp_url
        }
    }


# ============ Run Application ============

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(
        "main:app",
        host="0.0.0.0",
        port=8000,
        reload=True
    )