"""
FastAPI Web Server for CADDesigner.
Web server implementation compatible with the OpenAI API specification.
"""

from contextlib import asynccontextmanager
import uvicorn

from bootstrap_env import load_project_env

load_project_env()

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware

from .state import server_state
from .routers import (
    health_router,
    agent_router,
    conversation_router,
    chat_router,
)
from .error_handlers import not_found_handler, internal_error_handler
from SimpleLLMFunc.logger import push_error, app_log
from SimpleLLMFunc.observability.langfuse_client import flush_all_observations


@asynccontextmanager
async def lifespan(app: FastAPI):
    """Application lifecycle management."""
    app_log("🚀 Initializing CADDesigner Web Server...")
    try:
        server_state.initialize()
        app_log("✅ CADDesigner initialized successfully!")
    except Exception as e:
        push_error(f"❌ Failed to initialize CADDesigner: {e}")
        raise

    yield

    app_log("🔄 Shutting down CADDesigner Web Server...")
    try:
        flush_all_observations()
        app_log("✅ Flushed Langfuse observations")
    except Exception as e:
        push_error(f"⚠️ Failed to flush Langfuse observations: {e}")


# Create the FastAPI application.
app = FastAPI(
    title="CADDesigner API",
    description="OpenAI-compatible API for CADDesigner",
    version="1.0.0",
    docs_url="/docs",
    redoc_url="/redoc",
    lifespan=lifespan,
)

# Add CORS middleware.
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # TODO: Restrict specific domains in production.
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# Register routers.
app.include_router(health_router)
app.include_router(agent_router)
app.include_router(conversation_router)
app.include_router(chat_router)

# Register error handlers.
app.add_exception_handler(404, not_found_handler)
app.add_exception_handler(500, internal_error_handler)


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