src/open_llm_vtuber/server.py

"""
Open-LLM-VTuber Server
========================
This module contains the WebSocket server for Open-LLM-VTuber, which handles
the WebSocket connections, serves static files, and manages the web tool.
It uses FastAPI for the server and Starlette for static file serving.
"""

import os
import shutil

from fastapi import FastAPI
from starlette.middleware.cors import CORSMiddleware
from starlette.responses import Response
from starlette.staticfiles import StaticFiles as StarletteStaticFiles

from .routes import init_client_ws_route, init_webtool_routes, init_proxy_route
from .service_context import ServiceContext
from .config_manager.utils import Config
from .openllm_vtuber_main import OpenLLMVTuberMain

# Create a custom StaticFiles class that adds CORS headers
class CORSStaticFiles(StarletteStaticFiles):
    """
    Static files handler that adds CORS headers to all responses.
    Needed because Starlette StaticFiles might bypass standard middleware.
    """

    async def get_response(self, path: str, scope):
        response = await super().get_response(path, scope)

        # Add CORS headers to all responses
        response.headers["Access-Control-Allow-Origin"] = "*"
        response.headers["Access-Control-Allow-Methods"] = "GET, OPTIONS"
        response.headers["Access-Control-Allow-Headers"] = "*"

        if path.endswith(".js"):
            response.headers["Content-Type"] = "application/javascript"

        return response


class AvatarStaticFiles(CORSStaticFiles):
    """
    Avatar files handler with security restrictions and CORS headers
    """

    async def get_response(self, path: str, scope):
        allowed_extensions = (".jpg", ".jpeg", ".png", ".gif", ".svg")
        if not any(path.lower().endswith(ext) for ext in allowed_extensions):
            return Response("Forbidden file type", status_code=403)
        response = await super().get_response(path, scope)
        return response


class WebSocketServer:
    """
    API server for Open-LLM-VTuber. This contains the websocket endpoint for the client, hosts the web tool, and serves static files.

    Creates and configures a FastAPI app, registers all routes
    (WebSocket, web tools, proxy) and mounts static assets with CORS.

    Args:
        config (Config): Application configuration containing system settings.
        default_context_cache (ServiceContext, optional):
            Pre‑initialized service context for sessions' service context to reference to.
            **If omitted, `initialize()` method needs to be called to load service context.**

    Notes:
        - If default_context_cache is omitted, call `await initialize()` to load service context cache.
        - Use `clean_cache()` to clear and recreate the local cache directory.
    """

    def __init__(self, config: Config, default_context_cache: ServiceContext = None):
        self.app = FastAPI(title="Open-LLM-VTuber Server")  # Added title for clarity
        self.config = config
        self.vtuber_main = None
        self.is_ready = False
        self.default_context_cache = (
            default_context_cache or ServiceContext()
        )  # Use provided context or initialize a new empty one waiting to be loaded
        # It will be populated during the initialize method call

        # Add global CORS middleware
        self.app.add_middleware(
            CORSMiddleware,
            allow_origins=["*"],
            allow_credentials=True,
            allow_methods=["*"],
            allow_headers=["*"],
        )

        
        # The context will be populated during the initialize step
        self.app.include_router(
            init_client_ws_route(default_context_cache=self.default_context_cache, server_instance=self)
        )

        # Initialize and include proxy routes if proxy is enabled
        system_config = config.system_config
        if hasattr(system_config, "enable_proxy") and system_config.enable_proxy:
            # Construct the server URL for the proxy
            host = system_config.host
            port = system_config.port
            server_url = f"ws://{host}:{port}/client-ws"
            self.app.include_router(
                init_proxy_route(server_url=server_url),
            )

        # Mount cache directory first (to ensure audio file access)
        if not os.path.exists("cache"):
            os.makedirs("cache")
        # Always ensure all required sing subdirectories exist
        os.makedirs("sing/original", exist_ok=True)
        os.makedirs("sing/tracks", exist_ok=True)
        self.app.mount(
            "/cache",
            CORSStaticFiles(directory="cache"),
            name="cache",
        )

        # Mount static files with CORS-enabled handlers
        self.app.mount(
            "/live2d-models",
            CORSStaticFiles(directory="live2d-models"),
            name="live2d-models",
        )
        self.app.mount(
            "/bg",
            CORSStaticFiles(directory="backgrounds"),
            name="backgrounds",
        )
        self.app.mount(
            "/avatars",
            AvatarStaticFiles(directory="avatars"),
            name="avatars",
        )
        self.app.mount(
            "/sing/tracks",
            CORSStaticFiles(directory="sing/tracks"),
            name="sing_tracks"
        )
        
        # Mount web tool directory separately from frontend
        self.app.mount(
            "/web-tool",
            CORSStaticFiles(directory="web_tool", html=True),
            name="web_tool",
        )

        # Mount main frontend last (as catch-all)
        self.app.mount(
            "/",
            CORSStaticFiles(directory="frontend", html=True),
            name="frontend",
        )
        self.is_ready = False

    async def initialize(self):
        """Asynchronously load the service context and VTuber Main logic."""
        import asyncio
        from loguru import logger
        import traceback
        
        await self.default_context_cache.load_from_config(self.config)
        
        try:
            configs_dict = self.config.model_dump()
        except:
            configs_dict = vars(self.config)

        # --- ĐOẠN SỬA LỖI: Tự động map persona_prompt sang system_prompt ---
        if isinstance(configs_dict, dict):
            char_cfg = configs_dict.get('character_config', {})
            
            # 1. Nếu system_prompt trống nhưng persona_prompt có dữ liệu, thì lấy persona_prompt
            if char_cfg.get('system_prompt') is None:
                char_cfg['system_prompt'] = char_cfg.get('persona_prompt', "")
            
            # 2. Đảm bảo các chuỗi quan trọng không bao giờ là None để tránh lỗi +=
            keys_to_fix = [
                'system_prompt', 'personality', 'instruction', 
                'system_with_tools', 'name', 'background'
            ]
            for key in keys_to_fix:
                if key in char_cfg and char_cfg[key] is None:
                    char_cfg[key] = ""
                # Kiểm tra cả ở cấp ngoài nếu có
                if key in configs_dict and configs_dict[key] is None:
                    configs_dict[key] = ""
        # -----------------------------------------------------------------
            
        try:
            self.vtuber_main = OpenLLMVTuberMain(
                configs=configs_dict, 
                loop=asyncio.get_running_loop()
            )
            self.is_ready = True 
            logger.info("✅ VTuber Main Logic initialized and Ready.")
        except Exception as e:
            self.is_ready = False 
            logger.error(f"❌ Failed to initialize VTuber Main: {e}")
            logger.error(traceback.format_exc())

    @staticmethod
    def clean_cache():
        """Clean the cache directory by removing and recreating it."""
        cache_dir = "cache"
        if os.path.exists(cache_dir):
            shutil.rmtree(cache_dir)
            os.makedirs(cache_dir)