// Package httputil provides HTTP utility functions for the KnowFoolery application.
package httputil

import (
	"github.com/gofiber/fiber/v3"

	"knowfoolery/backend/shared/domain/errors"
)

// ErrorResponse represents a standard error response.
type ErrorResponse struct {
	Error   bool   `json:"error"`
	Code    string `json:"code,omitempty"`
	Message string `json:"message"`
	Details string `json:"details,omitempty"`
}

// NewErrorResponse creates a new ErrorResponse.
func NewErrorResponse(code, message, details string) ErrorResponse {
	return ErrorResponse{
		Error:   true,
		Code:    code,
		Message: message,
		Details: details,
	}
}

// SendError sends an error response with the appropriate HTTP status code.
func SendError(c fiber.Ctx, err error) error {
	statusCode, response := MapError(err)
	return c.Status(statusCode).JSON(response)
}

// MapError maps a domain error to an HTTP status code and response.
func MapError(err error) (int, ErrorResponse) {
	if err == nil {
		return fiber.StatusInternalServerError, NewErrorResponse(
			"INTERNAL",
			"An unexpected error occurred",
			"",
		)
	}

	domainErr, ok := err.(*errors.DomainError)
	if !ok {
		return fiber.StatusInternalServerError, NewErrorResponse(
			"INTERNAL",
			"An unexpected error occurred",
			err.Error(),
		)
	}

	statusCode := mapErrorCodeToStatus(domainErr.Code)
	return statusCode, NewErrorResponse(
		domainErr.Code.String(),
		domainErr.Message,
		"",
	)
}

// mapErrorCodeToStatus maps an error code to an HTTP status code.
func mapErrorCodeToStatus(code errors.ErrorCode) int {
	switch code {
	case errors.CodeNotFound, errors.CodeQuestionNotFound, errors.CodeUserNotFound:
		return fiber.StatusNotFound
	case errors.CodeInvalidInput, errors.CodeValidationFailed, errors.CodeInvalidPlayerName, errors.CodeInvalidAnswer:
		return fiber.StatusBadRequest
	case errors.CodeUnauthorized, errors.CodeInvalidToken, errors.CodeTokenExpired:
		return fiber.StatusUnauthorized
	case errors.CodeForbidden, errors.CodeMFARequired:
		return fiber.StatusForbidden
	case errors.CodeConflict, errors.CodeUserAlreadyExists, errors.CodeGameInProgress:
		return fiber.StatusConflict
	case errors.CodeRateLimitExceeded:
		return fiber.StatusTooManyRequests
	case errors.CodeSessionExpired, errors.CodeSessionNotActive:
		return fiber.StatusGone
	case errors.CodeMaxAttemptsReached:
		return fiber.StatusUnprocessableEntity
	default:
		return fiber.StatusInternalServerError
	}
}

// BadRequest sends a 400 Bad Request response.
func BadRequest(c fiber.Ctx, message string) error {
	return c.Status(fiber.StatusBadRequest).JSON(NewErrorResponse(
		"BAD_REQUEST",
		message,
		"",
	))
}

// Unauthorized sends a 401 Unauthorized response.
func Unauthorized(c fiber.Ctx, message string) error {
	return c.Status(fiber.StatusUnauthorized).JSON(NewErrorResponse(
		"UNAUTHORIZED",
		message,
		"",
	))
}

// Forbidden sends a 403 Forbidden response.
func Forbidden(c fiber.Ctx, message string) error {
	return c.Status(fiber.StatusForbidden).JSON(NewErrorResponse(
		"FORBIDDEN",
		message,
		"",
	))
}

// NotFound sends a 404 Not Found response.
func NotFound(c fiber.Ctx, message string) error {
	return c.Status(fiber.StatusNotFound).JSON(NewErrorResponse(
		"NOT_FOUND",
		message,
		"",
	))
}

// Conflict sends a 409 Conflict response.
func Conflict(c fiber.Ctx, message string) error {
	return c.Status(fiber.StatusConflict).JSON(NewErrorResponse(
		"CONFLICT",
		message,
		"",
	))
}

// TooManyRequests sends a 429 Too Many Requests response.
func TooManyRequests(c fiber.Ctx, message string, retryAfter int) error {
	c.Set("Retry-After", string(rune(retryAfter)))
	return c.Status(fiber.StatusTooManyRequests).JSON(NewErrorResponse(
		"RATE_LIMIT_EXCEEDED",
		message,
		"",
	))
}

// InternalError sends a 500 Internal Server Error response.
func InternalError(c fiber.Ctx, message string) error {
	return c.Status(fiber.StatusInternalServerError).JSON(NewErrorResponse(
		"INTERNAL",
		message,
		"",
	))
}