// GoToSocial // Copyright (C) GoToSocial Authors admin@gotosocial.org // SPDX-License-Identifier: AGPL-3.0-or-later // // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU Affero General Public License as published by // the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU Affero General Public License for more details. // // You should have received a copy of the GNU Affero General Public License // along with this program. If not, see <http://www.gnu.org/licenses/>. package text import ( "bytes" "html" "html/template" apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model" "github.com/superseriousbusiness/gotosocial/internal/regexes" ) // EmojifyWeb replaces emoji shortcodes like `:example:` in the given HTML // fragment with `<img>` tags suitable for rendering on the web frontend. func EmojifyWeb(emojis []apimodel.Emoji, html template.HTML) template.HTML { out := emojify( emojis, string(html), func(url, staticURL, code string, buf *bytes.Buffer) { // Open a picture tag so we // can present multiple options. buf.WriteString(`<picture>`) // Static version. buf.WriteString(`<source `) { buf.WriteString(`class="emoji" `) buf.WriteString(`srcset="` + staticURL + `" `) buf.WriteString(`type="image/png" `) // Show this version when user // doesn't want an animated emoji. buf.WriteString(`media="(prefers-reduced-motion: reduce)" `) // Limit size to avoid showing // huge emojis when unstyled. buf.WriteString(`width="25" height="25" `) } buf.WriteString(`/>`) // Original image source. buf.WriteString(`<img `) { buf.WriteString(`class="emoji" `) buf.WriteString(`src="` + url + `" `) buf.WriteString(`title=":` + code + `:" `) buf.WriteString(`alt=":` + code + `:" `) // Lazy load emojis when // they scroll into view. buf.WriteString(`loading="lazy" `) // Limit size to avoid showing // huge emojis when unstyled. buf.WriteString(`width="25" height="25" `) } buf.WriteString(`/>`) // Close the picture tag. buf.WriteString(`</picture>`) }, ) // If input was safe, // we can trust output. return template.HTML(out) // #nosec G203 } // EmojifyRSS replaces emoji shortcodes like `:example:` in the given text // fragment with `<img>` tags suitable for rendering as RSS content. func EmojifyRSS(emojis []apimodel.Emoji, text string) string { return emojify( emojis, text, func(url, staticURL, code string, buf *bytes.Buffer) { // Original image source. buf.WriteString(`<img `) { buf.WriteString(`src="` + url + `" `) buf.WriteString(`title=":` + code + `:" `) buf.WriteString(`alt=":` + code + `:" `) // Limit size to avoid showing // huge emojis in RSS readers. buf.WriteString(`width="25" height="25" `) } buf.WriteString(`/>`) }, ) } // Demojify replaces emoji shortcodes like `:example:` in the given text // fragment with empty strings, essentially stripping them from the text. // This is useful for text used in OG Meta headers. func Demojify(text string) string { return regexes.EmojiFinder.ReplaceAllString(text, "") } func emojify( emojis []apimodel.Emoji, input string, write func(url, staticURL, code string, buf *bytes.Buffer), ) string { // Build map of shortcodes. Normalize each // shortcode by readding closing colons. emojisMap := make(map[string]apimodel.Emoji, len(emojis)) for _, emoji := range emojis { shortcode := ":" + emoji.Shortcode + ":" emojisMap[shortcode] = emoji } return regexes.ReplaceAllStringFunc( regexes.EmojiFinder, input, func(shortcode string, buf *bytes.Buffer) string { // Look for emoji with this shortcode. emoji, ok := emojisMap[shortcode] if !ok { return shortcode } // Escape raw emoji content. url := html.EscapeString(emoji.URL) staticURL := html.EscapeString(emoji.StaticURL) code := html.EscapeString(emoji.Shortcode) // Write emoji repr to buffer. write(url, staticURL, code, buf) return buf.String() }, ) }