package api

import (
	"encoding/json"
	"time"

	"github.com/mayswind/ezbookkeeping/pkg/core"
	"github.com/mayswind/ezbookkeeping/pkg/errs"
	"github.com/mayswind/ezbookkeeping/pkg/log"
	"github.com/mayswind/ezbookkeeping/pkg/models"
	"github.com/mayswind/ezbookkeeping/pkg/services"
	"github.com/mayswind/ezbookkeeping/pkg/utils"
)

// UserApplicationCloudSettingsApi represents user application cloud settings api
type UserApplicationCloudSettingsApi struct {
	userAppCloudSettings *services.UserApplicationCloudSettingsService
	users                *services.UserService
}

// Initialize a user application cloud settings api singleton instance
var (
	UserApplicationCloudSettings = &UserApplicationCloudSettingsApi{
		userAppCloudSettings: services.UserApplicationCloudSettings,
		users:                services.Users,
	}
)

// ApplicationSettingsGetHandler returns application cloud settings of current user
func (a *UserApplicationCloudSettingsApi) ApplicationSettingsGetHandler(c *core.WebContext) (any, *errs.Error) {
	uid := c.GetCurrentUid()

	userApplicationCloudSettings, err := a.userAppCloudSettings.GetUserApplicationCloudSettingsByUid(c, uid)

	if err != nil {
		log.Errorf(c, "[user_app_cloud_settings.ApplicationSettingsGetHandler] failed to get latest user application cloud settings for user \"uid:%d\", because %s", uid, err.Error())
		return nil, errs.Or(err, errs.ErrOperationFailed)
	}

	if userApplicationCloudSettings == nil {
		return false, nil
	}

	applicationCloudSettingSlice := userApplicationCloudSettings.Settings

	if len(applicationCloudSettingSlice) < 1 {
		return false, nil
	}

	return applicationCloudSettingSlice, nil
}

// ApplicationSettingsUpdateHandler updates user application cloud settings by request parameters for current user
func (a *UserApplicationCloudSettingsApi) ApplicationSettingsUpdateHandler(c *core.WebContext) (any, *errs.Error) {
	var userAppCloudSettingUpdateReq models.UserApplicationCloudSettingsUpdateRequest
	err := c.ShouldBindJSON(&userAppCloudSettingUpdateReq)

	if err != nil {
		log.Warnf(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] parse request failed, because %s", err.Error())
		return false, errs.NewIncompleteOrIncorrectSubmissionError(err)
	}

	uid := c.GetCurrentUid()
	user, err := a.users.GetUserById(c, uid)

	if err != nil {
		if !errs.IsCustomError(err) {
			log.Warnf(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] failed to get user for user \"uid:%d\", because %s", uid, err.Error())
		}

		return false, errs.ErrUserNotFound
	}

	if user.FeatureRestriction.Contains(core.USER_FEATURE_RESTRICTION_TYPE_SYNC_APPLICATION_SETTINGS) {
		return false, errs.ErrNotPermittedToPerformThisAction
	}

	var userApplicationCloudSettings *models.UserApplicationCloudSetting

	// Retry up to 3 times
	for i := 0; i < 3; i++ {
		userApplicationCloudSettings, err = a.userAppCloudSettings.GetUserApplicationCloudSettingsByUid(c, uid)

		if err != nil {
			log.Errorf(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] failed to get latest user application cloud settings for user \"uid:%d\" (try count %d), because %s", uid, i+1, err.Error())
			return false, errs.Or(err, errs.ErrOperationFailed)
		}

		oldApplicationCloudSettingsMap := make(map[string]models.ApplicationCloudSetting)
		lastUpdateTime := int64(0)

		if userApplicationCloudSettings != nil {
			for _, setting := range userApplicationCloudSettings.Settings {
				oldApplicationCloudSettingsMap[setting.SettingKey] = setting
			}

			lastUpdateTime = userApplicationCloudSettings.UpdatedUnixTime
		}

		// Check if the full update settings are the same as the existing settings
		if userAppCloudSettingUpdateReq.FullUpdate {
			if len(userAppCloudSettingUpdateReq.Settings) == len(oldApplicationCloudSettingsMap) {
				needUpdate := false

				for _, setting := range userAppCloudSettingUpdateReq.Settings {
					oldSetting, exists := oldApplicationCloudSettingsMap[setting.SettingKey]

					if !exists || oldSetting.SettingValue != setting.SettingValue {
						needUpdate = true
						break
					}
				}

				if !needUpdate {
					return false, errs.ErrNothingWillBeUpdated
				}
			}
		} else { // Check if the partial update settings are the same as the existing settings or the settings to update are not set to sync
			needUpdate := true

			for _, setting := range userAppCloudSettingUpdateReq.Settings {
				cloudSetting, exists := oldApplicationCloudSettingsMap[setting.SettingKey]

				if !exists {
					needUpdate = false
					log.Infof(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] user application cloud setting key \"%s\" is not set to sync (try count %d)", setting.SettingKey, i+1)
				} else if cloudSetting.SettingValue == setting.SettingValue {
					needUpdate = false
					log.Infof(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] user application cloud setting key \"%s\" value \"%s\" is not changed, no need to update (try count %d)", setting.SettingKey, setting.SettingValue, i+1)
				}
			}

			if !needUpdate {
				log.Infof(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] no user application cloud settings need to update for user \"uid:%d\" (try count %d)", uid, i+1)
				return true, nil
			}
		}

		newApplicationCloudSettingsMap := make(map[string]models.ApplicationCloudSetting)
		var newApplicationCloudSettingSlice models.ApplicationCloudSettingSlice

		if userAppCloudSettingUpdateReq.FullUpdate {
			log.Infof(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] user \"uid:%d\" application cloud settings force update, will overwrite all existing settings (try count %d)", uid, i+1)
		} else {
			if len(oldApplicationCloudSettingsMap) > 0 {
				log.Infof(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] user \"uid:%d\" application cloud settings exists, try to merge it with request settings (try count %d)", uid, i+1)
				newApplicationCloudSettingsMap = oldApplicationCloudSettingsMap
			}
		}

		for _, setting := range userAppCloudSettingUpdateReq.Settings {
			newApplicationCloudSettingsMap[setting.SettingKey] = setting
		}

		for settingKey, setting := range newApplicationCloudSettingsMap {
			settingType, exists := models.ALL_ALLOWED_CLOUD_SYNC_APP_SETTING_KEY_TYPES[settingKey]

			if !exists {
				log.Warnf(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] user application cloud setting key \"%s\" is not supported to sync (try count %d)", settingKey, i+1)
				continue
			}

			if settingType == models.USER_APPLICATION_CLOUD_SETTING_TYPE_STRING {
				// Do Nothing
			} else if settingType == models.USER_APPLICATION_CLOUD_SETTING_TYPE_NUMBER {
				_, err := utils.StringToFloat64(setting.SettingValue)

				if err != nil {
					log.Warnf(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] user application cloud setting key \"%s\" has invalid number value \"%s\" (try count %d)", settingKey, setting.SettingValue, i+1)
					continue
				}
			} else if settingType == models.USER_APPLICATION_CLOUD_SETTING_TYPE_BOOLEAN {
				if setting.SettingValue != "true" && setting.SettingValue != "false" {
					log.Warnf(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] user application cloud setting key \"%s\" has invalid boolean value \"%s\" (try count %d)", settingKey, setting.SettingValue, i+1)
					continue
				}
			} else if settingType == models.USER_APPLICATION_CLOUD_SETTING_TYPE_STRING_BOOLEAN_MAP {
				var settingValueMap map[string]bool
				err := json.Unmarshal([]byte(setting.SettingValue), &settingValueMap)

				if err != nil {
					log.Warnf(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] user application cloud setting key \"%s\" has invalid map value \"%s\" (try count %d), because %s", settingKey, setting.SettingValue, i+1, err.Error())
					continue
				}
			} else {
				log.Warnf(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] user application cloud setting key \"%s\" has unknown type \"%s\" (try count %d)", settingKey, settingType, i+1)
				continue
			}

			newApplicationCloudSettingSlice = append(newApplicationCloudSettingSlice, setting)
		}

		err = a.userAppCloudSettings.UpdateUserApplicationCloudSettings(c, uid, newApplicationCloudSettingSlice, userAppCloudSettingUpdateReq.FullUpdate, lastUpdateTime)

		if err == nil {
			break
		}

		time.Sleep(100 * time.Millisecond) // Wait for 100 milliseconds before retrying
	}

	if err != nil {
		log.Errorf(c, "[user_app_cloud_settings.ApplicationSettingsUpdateHandler] failed to update user application cloud settings for user \"uid:%d\", because %s", uid, err.Error())
		return false, errs.Or(err, errs.ErrOperationFailed)
	}

	return true, nil
}

// ApplicationSettingsDisableHandler disabled user application cloud settings by request parameters for current user
func (a *UserApplicationCloudSettingsApi) ApplicationSettingsDisableHandler(c *core.WebContext) (any, *errs.Error) {
	uid := c.GetCurrentUid()
	user, err := a.users.GetUserById(c, uid)

	if err != nil {
		if !errs.IsCustomError(err) {
			log.Warnf(c, "[user_app_cloud_settings.ApplicationSettingsDisableHandler] failed to get user for user \"uid:%d\", because %s", uid, err.Error())
		}

		return false, errs.ErrUserNotFound
	}

	if user.FeatureRestriction.Contains(core.USER_FEATURE_RESTRICTION_TYPE_SYNC_APPLICATION_SETTINGS) {
		return false, errs.ErrNotPermittedToPerformThisAction
	}

	err = a.userAppCloudSettings.ClearUserApplicationCloudSettings(c, uid)

	if err != nil {
		log.Errorf(c, "[user_app_cloud_settings.ApplicationSettingsDisableHandler] failed to clear user application cloud settings for user \"uid:%d\", because %s", uid, err.Error())
		return false, errs.Or(err, errs.ErrOperationFailed)
	}

	return true, nil
}