GlobalExceptionHandler.java

package ch.fhnw.timerecordingbackend.excpetion;

import jakarta.validation.ValidationException;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.HttpStatusCode;
import org.springframework.http.ResponseEntity;
import org.springframework.security.access.AccessDeniedException;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.context.request.WebRequest;
import org.springframework.web.server.ResponseStatusException;
import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

@ControllerAdvice
public class GlobalExceptionHandler extends ResponseEntityExceptionHandler {

    @Override
    protected ResponseEntity<Object> handleMethodArgumentNotValid(
            MethodArgumentNotValidException ex, HttpHeaders headers, HttpStatusCode status, WebRequest request) {
        Map<String, Object> body = new HashMap<>();
        List<String> errors = ex.getBindingResult()
                .getFieldErrors()
                .stream()
                .map(error -> error.getField() + ": " + error.getDefaultMessage())
                .collect(Collectors.toList());
        body.put("timestamp", System.currentTimeMillis());
        body.put("status", status.value());
        body.put("errors", errors);
        body.put("message", "Validation failed for arguments");
        return new ResponseEntity<>(body, headers, status);
    }

    @ExceptionHandler(ValidationException.class)
    public ResponseEntity<Object> handleValidationException(ValidationException ex, WebRequest request) {
        Map<String, Object> body = new HashMap<>();
        body.put("timestamp", System.currentTimeMillis());
        body.put("status", HttpStatus.BAD_REQUEST.value());
        body.put("error", "Bad Request");
        body.put("message", ex.getMessage()); // Message from the service layer
        body.put("path", request.getDescription(false).substring(4)); // Extract URI
        return new ResponseEntity<>(body, HttpStatus.BAD_REQUEST);
    }

    @ExceptionHandler(IllegalArgumentException.class)
    public ResponseEntity<Object> handleIllegalArgumentException(IllegalArgumentException ex, WebRequest request) {
        Map<String, Object> body = new HashMap<>();
        body.put("timestamp", System.currentTimeMillis());
        body.put("status", HttpStatus.BAD_REQUEST.value());
        body.put("error", "Bad Request");
        body.put("message", ex.getMessage());
        body.put("path", request.getDescription(false).substring(4));
        return new ResponseEntity<>(body, HttpStatus.BAD_REQUEST);
    }

    @ExceptionHandler(ResponseStatusException.class)
    public ResponseEntity<Object> handleResponseStatusException(ResponseStatusException ex, WebRequest request) {
        Map<String, Object> body = new HashMap<>();
        body.put("timestamp", System.currentTimeMillis());
        body.put("status", ex.getStatusCode().value());
        body.put("error", HttpStatus.resolve(ex.getStatusCode().value()).getReasonPhrase());
        body.put("message", ex.getReason()); // Use getReason() for the message
        body.put("path", request.getDescription(false).substring(4));
        return new ResponseEntity<>(body, ex.getStatusCode());
    }

    @ExceptionHandler(AccessDeniedException.class)
    public ResponseEntity<Object> handleAccessDeniedException(AccessDeniedException ex, WebRequest request) {
        Map<String, Object> body = new HashMap<>();
        body.put("timestamp", System.currentTimeMillis());
        body.put("status", HttpStatus.FORBIDDEN.value());
        body.put("error", "Forbidden");
        body.put("message", ex.getMessage());
        body.put("path", request.getDescription(false).substring(4));
        return new ResponseEntity<>(body, HttpStatus.FORBIDDEN);
    }

    // Fallback for other exceptions
    @ExceptionHandler(Exception.class)
    public ResponseEntity<Object> handleAllOtherExceptions(Exception ex, WebRequest request) {
        Map<String, Object> body = new HashMap<>();
        body.put("timestamp", System.currentTimeMillis());
        body.put("status", HttpStatus.INTERNAL_SERVER_ERROR.value());
        body.put("error", "Internal Server Error");
        body.put("message", "An unexpected error occurred: " + ex.getMessage());
        body.put("path", request.getDescription(false).substring(4));
        // Log the exception for server-side analysis
        // logger.error("Unexpected error occurred", ex);
        return new ResponseEntity<>(body, HttpStatus.INTERNAL_SERVER_ERROR);
    }
}