import os
from fastapi import FastAPI, Request
from fastapi.responses import HTMLResponse, RedirectResponse
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates
from starlette.middleware.sessions import SessionMiddleware
from authlib.integrations.starlette_client import OAuth

from math_server import mcp as math_mcp

# -------------------------------
# Directories
# -------------------------------
BASE_DIR = os.path.dirname(__file__)
STATIC_DIR = os.path.join(BASE_DIR, "static")
TEMPLATES_DIR = os.path.join(BASE_DIR, "templates")

# -------------------------------
# App FastAPI
# -------------------------------
app = FastAPI()

# Session middleware nécessaire pour OAuth
app.add_middleware(SessionMiddleware, secret_key=os.environ.get("SESSION_SECRET", "UN_SECRET_123"))

# Static files
app.mount("/static", StaticFiles(directory=STATIC_DIR), name="static")
templates = Jinja2Templates(directory=TEMPLATES_DIR)

# -------------------------------
# Twitter OAuth configuration
# -------------------------------
oauth = OAuth()
oauth.register(
    name="twitter",
    client_id=os.environ.get("TWITTER_CLIENT_ID"),
    client_secret=os.environ.get("TWITTER_CLIENT_SECRET"),
    request_token_url=None,
    access_token_url="https://api.twitter.com/2/oauth2/token",
    authorize_url="https://twitter.com/i/oauth2/authorize",
    client_kwargs={"scope": "tweet.read users.read offline.access"},
)

# -------------------------------
# Endpoint racine
# -------------------------------
@app.get("/", response_class=HTMLResponse)
async def index(request: Request):
    space_host = os.environ.get("SPACE_HOST")
    if space_host and space_host.strip():
        base_url = space_host.strip().rstrip("/")
    else:
        base_url = f"{request.url.scheme}://{request.url.netloc}"
    
    user = request.session.get("user")
    return templates.TemplateResponse("index.html", {"request": request, "base_url": base_url, "user": user})

# -------------------------------
# Twitter OAuth endpoints
# -------------------------------
@app.get("/auth/twitter/login")
async def login(request: Request):
    redirect_uri = request.url_for("auth_callback")
    return await oauth.twitter.authorize_redirect(request, redirect_uri)

@app.get("/auth/twitter/callback")
async def auth_callback(request: Request):
    token = await oauth.twitter.authorize_access_token(request)
    user_info = await oauth.twitter.parse_id_token(request, token)
    request.session["user"] = {"id": user_info.get("sub"), "username": user_info.get("name")}
    return RedirectResponse(url="/")

@app.get("/auth/logout")
async def logout(request: Request):
    request.session.pop("user", None)
    return RedirectResponse(url="/")

# -------------------------------
# Endpoint MCP math
# -------------------------------
app.mount("/math", math_mcp.http_app())  # juste le HTTP app, pas besoin de run()

# -------------------------------
# Lancer le serveur
# -------------------------------
PORT = int(os.environ.get("PORT", "10000"))

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=PORT)