package middleware

import (
	"errors"

	"a301_server/pkg/apperror"

	"github.com/gofiber/fiber/v2"
)

// ErrorHandler is a Fiber error handler that returns structured JSON for AppError.
// Includes requestID in error responses for log correlation.
func ErrorHandler(c *fiber.Ctx, err error) error {
	requestID, _ := c.Locals("requestID").(string)

	var appErr *apperror.AppError
	if errors.As(err, &appErr) {
		resp := fiber.Map{
			"error":   appErr.Code,
			"message": appErr.Message,
		}
		if requestID != "" {
			resp["requestId"] = requestID
		}
		return c.Status(appErr.Status).JSON(resp)
	}

	// Default Fiber error handling
	var fiberErr *fiber.Error
	if errors.As(err, &fiberErr) {
		resp := fiber.Map{
			"error":   "server_error",
			"message": fiberErr.Message,
		}
		if requestID != "" {
			resp["requestId"] = requestID
		}
		return c.Status(fiberErr.Code).JSON(resp)
	}

	resp := fiber.Map{
		"error":   "internal_error",
		"message": "서버 오류가 발생했습니다",
	}
	if requestID != "" {
		resp["requestId"] = requestID
	}
	return c.Status(500).JSON(resp)
}