package com.cfdeployer.exception;

import com.cfdeployer.model.CfDeployResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.RestControllerAdvice;
import org.springframework.web.multipart.MaxUploadSizeExceededException;

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

@RestControllerAdvice
public class GlobalExceptionHandler {

    private static final Logger log = LoggerFactory.getLogger(GlobalExceptionHandler.class);

    @ExceptionHandler(MethodArgumentNotValidException.class)
    public ResponseEntity<CfDeployResponse> handleValidationExceptions(MethodArgumentNotValidException ex) {
        log.error("Validation error occurred", ex);

        Map<String, String> errors = new HashMap<>();
        ex.getBindingResult().getAllErrors().forEach((error) -> {
            String fieldName = ((FieldError) error).getField();
            String errorMessage = error.getDefaultMessage();
            errors.put(fieldName, errorMessage);
        });

        String errorMessage = errors.entrySet().stream()
                .map(entry -> entry.getKey() + ": " + entry.getValue())
                .collect(Collectors.joining(", "));

        CfDeployResponse response = CfDeployResponse.failure(
                "Validation failed: " + errorMessage,
                ex.getMessage()
        );

        return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(response);
    }

    @ExceptionHandler(MaxUploadSizeExceededException.class)
    public ResponseEntity<CfDeployResponse> handleMaxUploadSizeExceededException(MaxUploadSizeExceededException ex) {
        log.error("File size exceeded maximum allowed size", ex);

        CfDeployResponse response = CfDeployResponse.failure(
                "File size exceeded maximum allowed size. Please ensure your files are within the 500MB limit.",
                ex.getMessage()
        );

        return ResponseEntity.status(HttpStatus.PAYLOAD_TOO_LARGE).body(response);
    }

    @ExceptionHandler(IllegalArgumentException.class)
    public ResponseEntity<CfDeployResponse> handleIllegalArgumentException(IllegalArgumentException ex) {
        log.error("Invalid argument provided", ex);

        CfDeployResponse response = CfDeployResponse.failure(
                ex.getMessage(),
                ex.toString()
        );

        return ResponseEntity.status(HttpStatus.BAD_REQUEST).body(response);
    }

    @ExceptionHandler(Exception.class)
    public ResponseEntity<CfDeployResponse> handleGenericException(Exception ex) {
        log.error("Unexpected error occurred", ex);

        CfDeployResponse response = CfDeployResponse.failure(
                "An unexpected error occurred: " + ex.getMessage(),
                ex.toString()
        );

        return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(response);
    }
}