from fastapi import Request, status
from fastapi.responses import JSONResponse
from fastapi.exceptions import RequestValidationError
from sqlalchemy.exc import SQLAlchemyError
from typing import Union, Dict, Any

from app.main import app


class BookstoreException(Exception):
    """Base exception for the bookstore application"""

    def __init__(
        self,
        status_code: int,
        detail: Union[str, Dict[str, Any]],
        headers: Dict[str, str] = None,
    ):
        self.status_code = status_code
        self.detail = detail
        self.headers = headers


@app.exception_handler(BookstoreException)
async def bookstore_exception_handler(request: Request, exc: BookstoreException):
    """Handler for custom bookstore exceptions"""
    return JSONResponse(
        status_code=exc.status_code,
        content={"detail": exc.detail},
        headers=exc.headers,
    )


@app.exception_handler(RequestValidationError)
async def validation_exception_handler(request: Request, exc: RequestValidationError):
    """Handler for request validation errors"""
    return JSONResponse(
        status_code=status.HTTP_422_UNPROCESSABLE_ENTITY,
        content={
            "detail": "Validation error",
            "errors": exc.errors(),
        },
    )


@app.exception_handler(SQLAlchemyError)
async def sqlalchemy_exception_handler(request: Request, exc: SQLAlchemyError):
    """Handler for database errors"""
    return JSONResponse(
        status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
        content={
            "detail": "Database error",
            "error": str(exc),
        },
    )


@app.exception_handler(Exception)
async def general_exception_handler(request: Request, exc: Exception):
    """Handler for unhandled exceptions"""
    return JSONResponse(
        status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
        content={
            "detail": "Internal server error",
            "error": str(exc),
        },
    )