Rewrite from TypeScript to Go

Complete rewrite of the Freebee Matrix bot as GogoBee using mautrix-go.

- E2EE with goolm (pure Go, no CGo/libolm) and cross-signing bootstrap
- 35+ plugins with dependency injection and ordered registration
- SQLite storage via modernc.org/sqlite (no CGo)
- Scheduler via robfig/cron for WOTD, holidays, birthdays, releases, etc.
- Optional LLM integration (Ollama) for sentiment, profanity, roasts, vibes
- Threaded trivia, three-tier profanity tracking, WOTD usage verification
- Multi-country holiday support with deduplication
- Quadratic XP curve, configurable bot display name, encrypted DMs

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/plugin/urls.go

@@ -0,0 +1,187 @@
+package plugin
+
+import (
+	"fmt"
+	"log/slog"
+	"net/http"
+	"os"
+	"regexp"
+	"strings"
+	"time"
+
+	"gogobee/internal/db"
+
+	"github.com/PuerkitoBio/goquery"
+	"maunium.net/go/mautrix"
+)
+
+var urlRe = regexp.MustCompile(`https?://[^\s<>"]+`)
+
+// URLsPlugin detects URLs in messages and previews og:title/og:description.
+type URLsPlugin struct {
+	Base
+	enabled    bool
+	httpClient *http.Client
+}
+
+// NewURLsPlugin creates a new URL preview plugin.
+func NewURLsPlugin(client *mautrix.Client) *URLsPlugin {
+	enabled := os.Getenv("FEATURE_URL_PREVIEW") != ""
+	return &URLsPlugin{
+		Base:    NewBase(client),
+		enabled: enabled,
+		httpClient: &http.Client{
+			Timeout: 3 * time.Second,
+		},
+	}
+}
+
+func (p *URLsPlugin) Name() string { return "urls" }
+
+func (p *URLsPlugin) Commands() []CommandDef {
+	return nil // No commands — purely passive
+}
+
+func (p *URLsPlugin) Init() error { return nil }
+
+func (p *URLsPlugin) OnReaction(_ ReactionContext) error { return nil }
+
+func (p *URLsPlugin) OnMessage(ctx MessageContext) error {
+	if !p.enabled {
+		return nil
+	}
+
+	// Skip command messages
+	if ctx.IsCommand {
+		return nil
+	}
+
+	urls := urlRe.FindAllString(ctx.Body, 5) // limit to 5 URLs per message
+	if len(urls) == 0 {
+		return nil
+	}
+
+	for _, u := range urls {
+		title, desc, err := p.fetchPreview(u)
+		if err != nil {
+			slog.Debug("urls: fetch preview failed", "url", u, "err", err)
+			continue
+		}
+
+		if title == "" && desc == "" {
+			continue
+		}
+
+		var preview strings.Builder
+		if title != "" {
+			preview.WriteString(fmt.Sprintf("Title: %s", title))
+		}
+		if desc != "" {
+			if preview.Len() > 0 {
+				preview.WriteString("\n")
+			}
+			// Truncate long descriptions
+			if len(desc) > 200 {
+				desc = desc[:200] + "..."
+			}
+			preview.WriteString(fmt.Sprintf("Description: %s", desc))
+		}
+
+		if err := p.SendReply(ctx.RoomID, ctx.EventID, preview.String()); err != nil {
+			slog.Error("urls: send preview", "err", err)
+		}
+	}
+
+	return nil
+}
+
+// fetchPreview retrieves og:title and og:description, checking cache first.
+func (p *URLsPlugin) fetchPreview(rawURL string) (string, string, error) {
+	d := db.Get()
+	now := time.Now().UTC().Unix()
+	cacheTTL := int64(24 * 60 * 60)
+
+	// Check cache
+	var title, desc string
+	var cachedAt int64
+	err := d.QueryRow(
+		`SELECT title, description, cached_at FROM url_cache WHERE url = ?`, rawURL,
+	).Scan(&title, &desc, &cachedAt)
+	if err == nil && now-cachedAt < cacheTTL {
+		return title, desc, nil
+	}
+
+	// Fetch from web
+	title, desc, err = p.scrapeOG(rawURL)
+	if err != nil {
+		return "", "", err
+	}
+
+	// Cache the result
+	_, cacheErr := d.Exec(
+		`INSERT INTO url_cache (url, title, description, cached_at) VALUES (?, ?, ?, ?)
+		 ON CONFLICT(url) DO UPDATE SET title = ?, description = ?, cached_at = ?`,
+		rawURL, title, desc, now, title, desc, now,
+	)
+	if cacheErr != nil {
+		slog.Error("urls: cache write", "err", cacheErr)
+	}
+
+	return title, desc, nil
+}
+
+// scrapeOG fetches a URL and extracts og:title and og:description.
+func (p *URLsPlugin) scrapeOG(rawURL string) (string, string, error) {
+	req, err := http.NewRequest("GET", rawURL, nil)
+	if err != nil {
+		return "", "", fmt.Errorf("create request: %w", err)
+	}
+	req.Header.Set("User-Agent", "GogoBee Bot/1.0")
+
+	resp, err := p.httpClient.Do(req)
+	if err != nil {
+		return "", "", fmt.Errorf("fetch: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return "", "", fmt.Errorf("status %d", resp.StatusCode)
+	}
+
+	doc, err := goquery.NewDocumentFromReader(resp.Body)
+	if err != nil {
+		return "", "", fmt.Errorf("parse HTML: %w", err)
+	}
+
+	title := ""
+	desc := ""
+
+	doc.Find("meta").Each(func(_ int, s *goquery.Selection) {
+		prop, _ := s.Attr("property")
+		content, _ := s.Attr("content")
+		switch prop {
+		case "og:title":
+			title = content
+		case "og:description":
+			desc = content
+		}
+	})
+
+	// Fallback to <title> tag if no og:title
+	if title == "" {
+		title = doc.Find("title").First().Text()
+	}
+
+	// Fallback to meta description
+	if desc == "" {
+		doc.Find("meta").Each(func(_ int, s *goquery.Selection) {
+			name, _ := s.Attr("name")
+			if strings.EqualFold(name, "description") {
+				content, _ := s.Attr("content")
+				desc = content
+			}
+		})
+	}
+
+	return strings.TrimSpace(title), strings.TrimSpace(desc), nil
+}