package validator

import (
	"errors"
	"strings"

	"apskel-pos-be/internal/constants"
	"apskel-pos-be/internal/contract"
	"apskel-pos-be/internal/entities"
)

type UserDeviceValidator interface {
	ValidateRegisterDeviceRequest(req *contract.RegisterUserDeviceRequest) (error, string)
	ValidateUpdateDeviceRequest(req *contract.UpdateUserDeviceRequest) (error, string)
	ValidateListDevicesRequest(req *contract.ListUserDevicesRequest) (error, string)
}

type UserDeviceValidatorImpl struct{}

func NewUserDeviceValidator() *UserDeviceValidatorImpl {
	return &UserDeviceValidatorImpl{}
}

var validDeviceTypes = map[entities.DeviceType]bool{
	entities.DeviceTypeMobile:  true,
	entities.DeviceTypeTablet:  true,
	entities.DeviceTypeDesktop: true,
}

var validPlatforms = map[entities.DevicePlatform]bool{
	entities.DevicePlatformAndroid: true,
	entities.DevicePlatformIOS:     true,
	entities.DevicePlatformWeb:     true,
}

func (v *UserDeviceValidatorImpl) ValidateRegisterDeviceRequest(req *contract.RegisterUserDeviceRequest) (error, string) {
	if req == nil {
		return errors.New("request body is required"), constants.MissingFieldErrorCode
	}

	if strings.TrimSpace(req.DeviceID) == "" {
		return errors.New("device_id is required"), constants.MissingFieldErrorCode
	}

	if len(req.DeviceID) > 255 {
		return errors.New("device_id must be at most 255 characters"), constants.MalformedFieldErrorCode
	}

	if req.DeviceName != "" && len(req.DeviceName) > 255 {
		return errors.New("device_name must be at most 255 characters"), constants.MalformedFieldErrorCode
	}

	if req.DeviceType != "" && !validDeviceTypes[req.DeviceType] {
		return errors.New("device_type must be one of: mobile, tablet, desktop"), constants.MalformedFieldErrorCode
	}

	if req.Platform != "" && !validPlatforms[req.Platform] {
		return errors.New("platform must be one of: android, ios, web"), constants.MalformedFieldErrorCode
	}

	if req.FCMToken != "" && len(req.FCMToken) > 512 {
		return errors.New("fcm_token must be at most 512 characters"), constants.MalformedFieldErrorCode
	}

	if req.AppVersion != "" && len(req.AppVersion) > 50 {
		return errors.New("app_version must be at most 50 characters"), constants.MalformedFieldErrorCode
	}

	if req.OsVersion != "" && len(req.OsVersion) > 50 {
		return errors.New("os_version must be at most 50 characters"), constants.MalformedFieldErrorCode
	}

	return nil, ""
}

func (v *UserDeviceValidatorImpl) ValidateUpdateDeviceRequest(req *contract.UpdateUserDeviceRequest) (error, string) {
	if req == nil {
		return errors.New("request body is required"), constants.MissingFieldErrorCode
	}

	if req.DeviceName != "" && len(req.DeviceName) > 255 {
		return errors.New("device_name must be at most 255 characters"), constants.MalformedFieldErrorCode
	}

	if req.DeviceType != "" && !validDeviceTypes[req.DeviceType] {
		return errors.New("device_type must be one of: mobile, tablet, desktop"), constants.MalformedFieldErrorCode
	}

	if req.Platform != "" && !validPlatforms[req.Platform] {
		return errors.New("platform must be one of: android, ios, web"), constants.MalformedFieldErrorCode
	}

	if req.FCMToken != "" && len(req.FCMToken) > 512 {
		return errors.New("fcm_token must be at most 512 characters"), constants.MalformedFieldErrorCode
	}

	if req.AppVersion != "" && len(req.AppVersion) > 50 {
		return errors.New("app_version must be at most 50 characters"), constants.MalformedFieldErrorCode
	}

	if req.OsVersion != "" && len(req.OsVersion) > 50 {
		return errors.New("os_version must be at most 50 characters"), constants.MalformedFieldErrorCode
	}

	return nil, ""
}

func (v *UserDeviceValidatorImpl) ValidateListDevicesRequest(req *contract.ListUserDevicesRequest) (error, string) {
	if req == nil {
		return errors.New("request body is required"), constants.MissingFieldErrorCode
	}

	if req.Page < 1 {
		return errors.New("page must be at least 1"), constants.MalformedFieldErrorCode
	}

	if req.Limit < 1 || req.Limit > 100 {
		return errors.New("limit must be between 1 and 100"), constants.MalformedFieldErrorCode
	}

	if req.Platform != "" && !validPlatforms[entities.DevicePlatform(req.Platform)] {
		return errors.New("platform must be one of: android, ios, web"), constants.MalformedFieldErrorCode
	}

	return nil, ""
}