package entity

// Channel is a square plaza instance (path prefix / data isolation).
type Channel string

const (
	ChannelSquare       Channel = "square"
	ChannelSquareNovel  Channel = "squarenovel"
	ChannelSquareSteps  Channel = "squaresteps"
	ChannelSquareHealth Channel = "squarehealth"
)

// Channels is the closed set of plaza instances.
func Channels() []Channel {
	return []Channel{ChannelSquare, ChannelSquareNovel, ChannelSquareSteps, ChannelSquareHealth}
}

func (c Channel) Valid() bool {
	switch c {
	case ChannelSquare, ChannelSquareNovel, ChannelSquareSteps, ChannelSquareHealth:
		return true
	default:
		return false
	}
}

func ParseChannel(s string) (Channel, bool) {
	c := Channel(s)
	if !c.Valid() {
		return "", false
	}
	return c, true
}

// Category is a feed tab / post tag under every channel.
// Feed modes (recommend/latest/hot/nearby) only affect list sort; tags are stored on posts.
type Category string

const (
	CategoryRecommend Category = "recommend"
	CategoryLatest    Category = "latest"
	CategoryHot       Category = "hot"
	CategoryNearby    Category = "nearby"
	CategoryFunny     Category = "funny"
	CategoryBeauty    Category = "beauty"
)

// Categories lists every filter tab (feed modes + tags).
func Categories() []Category {
	return []Category{
		CategoryRecommend, CategoryLatest, CategoryHot, CategoryNearby,
		CategoryFunny, CategoryBeauty,
	}
}

// PublishCategories are tags that may be written on a post.
func PublishCategories() []Category {
	return []Category{CategoryFunny, CategoryBeauty}
}

func (c Category) Valid() bool {
	switch c {
	case CategoryRecommend, CategoryLatest, CategoryHot, CategoryNearby,
		CategoryFunny, CategoryBeauty, "":
		return true
	default:
		return false
	}
}

func (c Category) IsFeedMode() bool {
	switch c {
	case CategoryRecommend, CategoryLatest, CategoryHot, CategoryNearby, "":
		return true
	default:
		return false
	}
}

func (c Category) IsTag() bool {
	switch c {
	case CategoryFunny, CategoryBeauty:
		return true
	default:
		return false
	}
}

func ParseCategory(s string) (Category, bool) {
	c := Category(s)
	if !c.Valid() {
		return "", false
	}
	return c, true
}

// FeedListQuery drives public feed filtering and sort in the repository.
type FeedListQuery struct {
	Cursor   int64
	Limit    int
	Category Category
	Lat      float64
	Lng      float64
}