package api

import (
	"encoding/json"
	"fmt"

	"golang.org/x/exp/slices"
)

type UserSettingKey string

const (
	// UserSettingLocaleKey is the key type for user locale.
	UserSettingLocaleKey UserSettingKey = "locale"
	// UserSettingAppearanceKey is the key type for user appearance.
	UserSettingAppearanceKey UserSettingKey = "appearance"
	// UserSettingMemoVisibilityKey is the key type for user preference memo default visibility.
	UserSettingMemoVisibilityKey UserSettingKey = "memoVisibility"
	// UserSettingMemoDisplayTsOptionKey is the key type for memo display ts option.
	UserSettingMemoDisplayTsOptionKey UserSettingKey = "memoDisplayTsOption"
)

// String returns the string format of UserSettingKey type.
func (key UserSettingKey) String() string {
	switch key {
	case UserSettingLocaleKey:
		return "locale"
	case UserSettingAppearanceKey:
		return "appearance"
	case UserSettingMemoVisibilityKey:
		return "memoVisibility"
	case UserSettingMemoDisplayTsOptionKey:
		return "memoDisplayTsOption"
	}
	return ""
}

var (
	UserSettingLocaleValue                 = []string{"en", "zh", "vi", "fr", "nl", "sv", "de", "es", "uk", "ru", "it"}
	UserSettingAppearanceValue             = []string{"system", "light", "dark"}
	UserSettingMemoVisibilityValue         = []Visibility{Private, Protected, Public}
	UserSettingMemoDisplayTsOptionKeyValue = []string{"created_ts", "updated_ts"}
)

type UserSetting struct {
	UserID int
	Key    UserSettingKey `json:"key"`
	// Value is a JSON string with basic value
	Value string `json:"value"`
}

type UserSettingUpsert struct {
	UserID int            `json:"-"`
	Key    UserSettingKey `json:"key"`
	Value  string         `json:"value"`
}

func (upsert UserSettingUpsert) Validate() error {
	if upsert.Key == UserSettingLocaleKey {
		localeValue := "en"
		err := json.Unmarshal([]byte(upsert.Value), &localeValue)
		if err != nil {
			return fmt.Errorf("failed to unmarshal user setting locale value")
		}
		if !slices.Contains(UserSettingLocaleValue, localeValue) {
			return fmt.Errorf("invalid user setting locale value")
		}
	} else if upsert.Key == UserSettingAppearanceKey {
		appearanceValue := "system"
		err := json.Unmarshal([]byte(upsert.Value), &appearanceValue)
		if err != nil {
			return fmt.Errorf("failed to unmarshal user setting appearance value")
		}
		if !slices.Contains(UserSettingAppearanceValue, appearanceValue) {
			return fmt.Errorf("invalid user setting appearance value")
		}
	} else if upsert.Key == UserSettingMemoVisibilityKey {
		memoVisibilityValue := Private
		err := json.Unmarshal([]byte(upsert.Value), &memoVisibilityValue)
		if err != nil {
			return fmt.Errorf("failed to unmarshal user setting memo visibility value")
		}
		if !slices.Contains(UserSettingMemoVisibilityValue, memoVisibilityValue) {
			return fmt.Errorf("invalid user setting memo visibility value")
		}
	} else if upsert.Key == UserSettingMemoDisplayTsOptionKey {
		memoDisplayTsOption := "created_ts"
		err := json.Unmarshal([]byte(upsert.Value), &memoDisplayTsOption)
		if err != nil {
			return fmt.Errorf("failed to unmarshal user setting memo display ts option")
		}
		if !slices.Contains(UserSettingMemoDisplayTsOptionKeyValue, memoDisplayTsOption) {
			return fmt.Errorf("invalid user setting memo display ts option value")
		}
	} else {
		return fmt.Errorf("invalid user setting key")
	}

	return nil
}

type UserSettingFind struct {
	UserID int

	Key *UserSettingKey `json:"key"`
}

type UserSettingDelete struct {
	UserID int
}