import logging

from fastapi import FastAPI, HTTPException, Request
from fastapi.exceptions import RequestValidationError
from fastapi.responses import JSONResponse

log = logging.getLogger("fraud.errors")


def install_exception_handlers(app: FastAPI) -> None:
    @app.exception_handler(RequestValidationError)
    async def _validation(_: Request, exc: RequestValidationError):
        return JSONResponse(
            status_code=422,
            content={
                "error": "VALIDATION_ERROR",
                "message": "Request validation failed",
                "details": {"errors": exc.errors()},
            },
        )

    @app.exception_handler(HTTPException)
    async def _http(_: Request, exc: HTTPException):
        detail = exc.detail
        if isinstance(detail, dict) and "error" in detail:
            payload = {
                "error": detail.get("error", "ERROR"),
                "message": detail.get("message", ""),
                "details": detail.get("details"),
            }
        else:
            payload = {"error": "ERROR", "message": str(detail), "details": None}
        return JSONResponse(status_code=exc.status_code, content=payload)

    @app.exception_handler(Exception)
    async def _unhandled(_: Request, exc: Exception):
        log.exception("Unhandled exception: %s", exc)
        return JSONResponse(
            status_code=500,
            content={"error": "INTERNAL_ERROR", "message": "Internal server error", "details": None},
        )