from uuid import uuid4

from fastapi import FastAPI, HTTPException, Request
from fastapi.exceptions import RequestValidationError
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
from sqlalchemy import text

from app.api.router import api_router
from app.core.config import get_settings
from app.core.database import SessionLocal

settings = get_settings()
app = FastAPI(
    title="Maskan CRM API",
    version="0.1.0",
    docs_url="/api/docs",
    openapi_url="/api/openapi.json",
)

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


def error_response(
    *,
    request: Request,
    status_code: int,
    code: str,
    message: str,
    details: object | None = None,
) -> JSONResponse:
    request_id = getattr(request.state, "request_id", str(uuid4()))
    return JSONResponse(
        status_code=status_code,
        content={
            "error": {
                "code": code,
                "message": message,
                "details": details,
                "request_id": request_id,
            },
        },
        headers={"X-Request-ID": request_id},
    )


@app.middleware("http")
async def request_id_middleware(request: Request, call_next):
    request.state.request_id = request.headers.get("X-Request-ID") or str(uuid4())
    response = await call_next(request)
    response.headers["X-Request-ID"] = request.state.request_id
    return response


@app.exception_handler(HTTPException)
async def http_exception_handler(request: Request, exc: HTTPException) -> JSONResponse:
    return error_response(
        request=request,
        status_code=exc.status_code,
        code=f"HTTP_{exc.status_code}",
        message=str(exc.detail),
    )


@app.exception_handler(RequestValidationError)
async def validation_exception_handler(
    request: Request,
    exc: RequestValidationError,
) -> JSONResponse:
    return error_response(
        request=request,
        status_code=422,
        code="VALIDATION_ERROR",
        message="One or more fields are invalid.",
        details=exc.errors(),
    )


@app.get("/health/live", tags=["Health"])
def live() -> dict[str, str]:
    return {"status": "ok", "service": "maskan-crm-api"}


@app.get("/health/ready", tags=["Health"])
def ready() -> dict[str, str]:
    with SessionLocal() as db:
        db.execute(text("SELECT 1"))
    return {"status": "ready", "database": "connected"}


@app.get("/api/v1/status", tags=["Health"])
def status() -> dict[str, str]:
    return {
        "product": "Maskan CRM",
        "mode": settings.mode,
        "environment": settings.environment,
    }


app.include_router(api_router)