text

Documentation

Overview

Package text provides a rich text API for cchat interfaces to use.

Asserting

Although interfaces here contain asserter methods similarly to cchat, the backend should take care to not implement multiple interfaces that may seem conflicting. For example, if Avatarer is already implemented, then Imager shouldn't be.

Index

• func SolidColor(rgb uint32) uint32
• type Attribute
  • func (a Attribute) Is(is Attribute) bool
• type Attributor
• type Avatarer
• type Codeblocker
• type Colorer
• type Imager
• type Linker
• type Mentioner
• type Quoteblocker
• type Rich
  • func Plain(text string) Rich
• type Segment

Functions

func SolidColor

func SolidColor(rgb uint32) uint32

SolidColor takes in a 24-bit RGB color and overrides the alpha bits with 0xFF, making the color solid.

Types

type Attribute

type Attribute uint32

Attribute is the type for basic rich text markup attributes.

const (
	// Normal is a zero-value attribute.
	AttributeNormal Attribute = iota
	// Bold represents bold text.
	AttributeBold
	// Italics represents italicized text.
	AttributeItalics
	// Underline represents underlined text.
	AttributeUnderline
	// Strikethrough represents struckthrough text.
	AttributeStrikethrough
	// Spoiler represents spoiler text, which usually looks blacked out until
	// hovered or clicked on.
	AttributeSpoiler
	// Monospace represents monospaced text, typically for inline code.
	AttributeMonospace
	// Dimmed represents dimmed text, typically slightly less visible than other
	// text.
	AttributeDimmed
)

func (Attribute) Is

func (a Attribute) Is(is Attribute) bool

type Attributor

type Attributor interface {
	Attribute() Attribute
}

Attributor is a rich text markup format that a segment could implement. This is to be applied directly onto the text.

type Avatarer

type Avatarer interface {
	// AvatarText returns the underlying text of the image. Frontends could use this
	// for hovering or displaying the text instead of the image.
	AvatarText() string
	// AvatarSize returns the requested dimension for the image. This function could
	// return (0, 0), which the frontend should use the avatar's dimensions.
	AvatarSize() (size int)
	// Avatar returns the URL for the image.
	Avatar() (url string)
}

Avatarer implies the segment should be replaced with a rounded-corners image. This works similarly to Imager.

For segments that also implement mentioner, the image should be treated as a round avatar.

type Codeblocker

type Codeblocker interface {
	CodeblockLanguage() (language string)
}

Codeblocker is a codeblock that supports optional syntax highlighting using the language given. Note that as this is a block, it will appear separately from the rest of the paragraph.

This interface is equivalent to Markdown's codeblock syntax.

type Colorer

type Colorer interface {
	// Color returns a 32-bit RGBA color.
	Color() uint32
}

Colorer is a text color format that a segment could implement. This is to be applied directly onto the text.

The Color method must return a valid 32-bit RGBA color. That is, if the text color is solid, then the alpha value must be 0xFF. Frontends that support 32-bit colors must render alpha accordingly without any edge cases.

type Imager

type Imager interface {
	// ImageText returns the underlying text of the image. Frontends could use this
	// for hovering or displaying the text instead of the image.
	ImageText() string
	// ImageSize returns the requested dimension for the image. This function could
	// return (0, 0), which the frontend should use the image's dimensions.
	ImageSize() (w int, h int)
	// Image returns the URL for the image.
	Image() (url string)
}

Imager implies the segment should be replaced with a (possibly inlined) image. Only the starting bound matters, as images cannot substitute texts.

For segments that also implement mentioner, the image should be treated as a square avatar.

type Linker

type Linker interface {
	Link() (url string)
}

Linker is a hyperlink format that a segment could implement. This implies that the segment should be replaced with a hyperlink, similarly to the anchor tag with href being the URL and the inner text being the text string.

type Mentioner

type Mentioner interface {
	// MentionInfo returns the popup information of the mentioned segment. This is
	// typically user information or something similar to that context.
	MentionInfo() Rich
}

Mentioner implies that the segment can be clickable, and when clicked it should open up a dialog containing information from MentionInfo().

It is worth mentioning that frontends should assume whatever segment that Mentioner highlighted to be the display name of that user. This would allow frontends to flexibly layout the labels.

type Quoteblocker

type Quoteblocker interface {
	// QuotePrefix returns the prefix that every line the segment covers have. This
	// is typically the greater-than sign ">" in Markdown. Frontends could use this
	// information to format the quote properly.
	QuotePrefix() (prefix string)
}

Quoteblocker represents a quoteblock that behaves similarly to the blockquote HTML tag. The quoteblock may be represented typically by an actaul quoteblock or with green arrows prepended to each line.

type Rich

type Rich struct {
	Content  string
	Segments []Segment
}

Rich is a normal text wrapped with optional format segments.

func Plain

func Plain(text string) Rich

Plain creates a new text.Rich without any formatting segments.

type Segment

type Segment interface {
	Bounds() (start int, end int)

	AsColorer() Colorer           // Optional
	AsLinker() Linker             // Optional
	AsImager() Imager             // Optional
	AsAvatarer() Avatarer         // Optional
	AsMentioner() Mentioner       // Optional
	AsAttributor() Attributor     // Optional
	AsCodeblocker() Codeblocker   // Optional
	AsQuoteblocker() Quoteblocker // Optional
}

Segment is the minimum requirement for a format segment. Frontends will use this to determine when the format starts and ends. They will also assert this interface to any other formatting interface, including Linker, Colorer and Attributor.

Note that a segment may implement multiple interfaces. For example, a Mentioner may also implement Colorer.