source: backend/src/main/java/mk/finki/roomreservation/exception/ApiExceptionHandler.java

package mk.finki.roomreservation.exception;

import org.springframework.dao.DataAccessException;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;

import java.util.Map;

@RestControllerAdvice
public class ApiExceptionHandler {

    @ExceptionHandler(IllegalArgumentException.class)
    public ResponseEntity<Map<String, String>> handleIllegalArgument(IllegalArgumentException ex) {
        return ResponseEntity
                .status(HttpStatus.BAD_REQUEST)
                .body(Map.of("message", ex.getMessage()));
    }

    @ExceptionHandler(DataAccessException.class)
    public ResponseEntity<Map<String, String>> handleDatabaseError(DataAccessException ex) {
        String message = ex.getMostSpecificCause() != null
                ? ex.getMostSpecificCause().getMessage()
                : ex.getMessage();

        return ResponseEntity
                .status(HttpStatus.BAD_REQUEST)
                .body(Map.of("message", message));
    }

    @ExceptionHandler(RuntimeException.class)
    public ResponseEntity<Map<String, String>> handleRuntime(RuntimeException ex) {
        return ResponseEntity
                .status(HttpStatus.BAD_REQUEST)
                .body(Map.of("message", ex.getMessage()));
    }
}