1 files changed, 96 insertions, 0 deletions
diff --git a/internal/util/statustools.go b/internal/util/statustools.go
new file mode 100644
index 000000000..5591f185a
--- /dev/null
+++ b/internal/util/statustools.go
@@ -0,0 +1,96 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   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 util
+
+import (
+	"strings"
+)
+
+// DeriveMentions takes a plaintext (ie., not html-formatted) status,
+// and applies a regex to it to return a deduplicated list of accounts
+// mentioned in that status.
+//
+// It will look for fully-qualified account names in the form "@user@example.org".
+// or the form "@username" for local users.
+// The case of the returned mentions will be lowered, for consistency.
+func DeriveMentions(status string) []string {
+	mentionedAccounts := []string{}
+	for _, m := range mentionFinderRegex.FindAllStringSubmatch(status, -1) {
+		mentionedAccounts = append(mentionedAccounts, m[1])
+	}
+	return lower(unique(mentionedAccounts))
+}
+
+// DeriveHashtags takes a plaintext (ie., not html-formatted) status,
+// and applies a regex to it to return a deduplicated list of hashtags
+// used in that status, without the leading #. The case of the returned
+// tags will be lowered, for consistency.
+func DeriveHashtags(status string) []string {
+	tags := []string{}
+	for _, m := range hashtagFinderRegex.FindAllStringSubmatch(status, -1) {
+		tags = append(tags, m[1])
+	}
+	return lower(unique(tags))
+}
+
+// DeriveEmojis takes a plaintext (ie., not html-formatted) status,
+// and applies a regex to it to return a deduplicated list of emojis
+// used in that status, without the surround ::. The case of the returned
+// emojis will be lowered, for consistency.
+func DeriveEmojis(status string) []string {
+	emojis := []string{}
+	for _, m := range emojiFinderRegex.FindAllStringSubmatch(status, -1) {
+		emojis = append(emojis, m[1])
+	}
+	return lower(unique(emojis))
+}
+
+// unique returns a deduplicated version of a given string slice.
+func unique(s []string) []string {
+	keys := make(map[string]bool)
+	list := []string{}
+	for _, entry := range s {
+		if _, value := keys[entry]; !value {
+			keys[entry] = true
+			list = append(list, entry)
+		}
+	}
+	return list
+}
+
+// lower lowercases all strings in a given string slice
+func lower(s []string) []string {
+	new := []string{}
+	for _, i := range s {
+		new = append(new, strings.ToLower(i))
+	}
+	return new
+}
+
+// HTMLFormat takes a plaintext formatted status string, and converts it into
+// a nice HTML-formatted string.
+//
+// This includes:
+// - Replacing line-breaks with <p>
+// - Replacing URLs with hrefs.
+// - Replacing mentions with links to that account's URL as stored in the database.
+func HTMLFormat(status string) string {
+	// TODO: write proper HTML formatting logic for a status
+	return status
+}