"""JIRA AI Fixer - Enterprise Issue Analysis Platform."""
from contextlib import asynccontextmanager
from fastapi import FastAPI, Request
from fastapi.middleware.cors import CORSMiddleware
from fastapi.staticfiles import StaticFiles
from fastapi.responses import FileResponse, RedirectResponse
from starlette.middleware.base import BaseHTTPMiddleware
import os

from app.core.config import settings
from app.core.database import init_db
from app.api import api_router

class HTTPSRedirectMiddleware(BaseHTTPMiddleware):
    """Force HTTPS in redirects when behind reverse proxy."""
    async def dispatch(self, request: Request, call_next):
        response = await call_next(request)
        # Fix Location header to use HTTPS if behind proxy
        if response.status_code in (301, 302, 303, 307, 308):
            location = response.headers.get("location", "")
            if location.startswith("http://"):
                response.headers["location"] = location.replace("http://", "https://", 1)
        return response

@asynccontextmanager
async def lifespan(app: FastAPI):
    # Startup
    await init_db()
    yield
    # Shutdown

app = FastAPI(
    title=settings.APP_NAME,
    version=settings.APP_VERSION,
    description="Enterprise AI-powered issue analysis and automated fix generation",
    docs_url="/api/docs",
    redoc_url="/api/redoc",
    openapi_url="/api/openapi.json",
    lifespan=lifespan,
    redirect_slashes=False  # Disable automatic slash redirects
)

# Add HTTPS redirect middleware
app.add_middleware(HTTPSRedirectMiddleware)

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

# API routes
app.include_router(api_router, prefix="/api")

# Health check
@app.get("/api/health")
async def health():
    return {
        "status": "healthy",
        "service": "jira-ai-fixer",
        "version": settings.APP_VERSION
    }

# Serve static frontend (will be mounted if exists)
FRONTEND_DIR = "/app/frontend"
ASSETS_DIR = f"{FRONTEND_DIR}/assets"

if os.path.exists(FRONTEND_DIR) and os.path.exists(ASSETS_DIR):
    app.mount("/assets", StaticFiles(directory=ASSETS_DIR), name="assets")
    
    @app.get("/")
    async def serve_frontend():
        return FileResponse(f"{FRONTEND_DIR}/index.html")
    
    @app.get("/{path:path}")
    async def serve_spa(path: str):
        if path.startswith("api/"):
            return None  # Let API routes handle
        file_path = f"{FRONTEND_DIR}/{path}"
        if os.path.exists(file_path) and os.path.isfile(file_path):
            return FileResponse(file_path)
        return FileResponse(f"{FRONTEND_DIR}/index.html")

# Fallback: serve basic info page when no frontend
@app.get("/")
async def root():
    return {
        "service": settings.APP_NAME,
        "version": settings.APP_VERSION,
        "docs": "/api/docs",
        "health": "/api/health"
    }