Add Discord outbound posting.

internal/discord/format.go

@@ -0,0 +1,75 @@
+package discord
+
+import (
+	"strings"
+
+	"plumber/internal/events"
+)
+
+const (
+	embedTitleLimit       = 256
+	embedDescriptionLimit = 4096
+	threadNameLimit       = 100
+	embedColor            = 0xe96a26
+)
+
+// Message is a Discord-ready snapshot of a site post event.
+type Message struct {
+	Title       string
+	URL         string
+	Description string
+	City        string
+	Author      string
+	ImageURLs   []string
+	ThreadName  string
+}
+
+func formatMessage(ev events.PostEvent) Message {
+	title := strings.TrimSpace(ev.Title)
+	if title == "" {
+		title = "Reply"
+	}
+	author := strings.TrimSpace(ev.AuthorName)
+	if author == "" {
+		author = "Someone"
+	}
+	msg := Message{
+		Title:       truncateRunes(title, embedTitleLimit),
+		URL:         strings.TrimSpace(ev.Permalink),
+		Description: truncateRunes(strings.TrimSpace(ev.Body), embedDescriptionLimit),
+		City:        strings.TrimSpace(ev.City),
+		Author:      author,
+		ThreadName:  threadName(ev.Title),
+	}
+	for _, img := range ev.Images {
+		url := strings.TrimSpace(img.URL)
+		if url == "" {
+			continue
+		}
+		msg.ImageURLs = append(msg.ImageURLs, url)
+	}
+	return msg
+}
+
+func threadName(title string) string {
+	title = strings.TrimSpace(title)
+	if title == "" {
+		return "Question"
+	}
+	return truncateRunes(title, threadNameLimit)
+}
+
+func truncateRunes(s string, max int) string {
+	if max <= 0 {
+		return ""
+	}
+	runes := []rune(s)
+	if len(runes) <= max {
+		return s
+	}
+	return string(runes[:max])
+}
+
+func isRoot(ev events.PostEvent) bool {
+	return strings.TrimSpace(ev.ParentID) == ""
+}