feat: domain blocker plugin

internal/plugin/domainblock/domainblock.go

@@ -0,0 +1,132 @@
+package domainblock
+
+import (
+	"fmt"
+	"net/url"
+	"regexp"
+	"strings"
+
+	"git.nakama.town/fmartingr/butterrobot/internal/model"
+	"git.nakama.town/fmartingr/butterrobot/internal/plugin"
+)
+
+// DomainBlockPlugin is a plugin that blocks messages containing links from specific domains
+type DomainBlockPlugin struct {
+	plugin.BasePlugin
+}
+
+// Debug helper to check if RequiresConfig is working
+func (p *DomainBlockPlugin) RequiresConfig() bool {
+	return true
+}
+
+// New creates a new DomainBlockPlugin instance
+func New() *DomainBlockPlugin {
+	return &DomainBlockPlugin{
+		BasePlugin: plugin.BasePlugin{
+			ID:             "security.domainblock",
+			Name:           "Domain Blocker",
+			Help:           "Blocks messages containing links from configured domains",
+			ConfigRequired: true,
+		},
+	}
+}
+
+// extractDomains extracts domains from a message text
+func extractDomains(text string) []string {
+	// URL regex pattern
+	urlPattern := regexp.MustCompile(`https?://([^\s/$.?#].[^\s]*)`)
+	matches := urlPattern.FindAllStringSubmatch(text, -1)
+
+	domains := make([]string, 0, len(matches))
+	for _, match := range matches {
+		if len(match) < 2 {
+			continue
+		}
+
+		// Try to parse the URL to extract the domain
+		urlStr := match[0]
+		parsedURL, err := url.Parse(urlStr)
+		if err != nil {
+			continue
+		}
+
+		// Extract the domain (host) from the URL
+		domain := parsedURL.Host
+		// Remove port if present
+		if i := strings.IndexByte(domain, ':'); i >= 0 {
+			domain = domain[:i]
+		}
+
+		domains = append(domains, strings.ToLower(domain))
+	}
+
+	return domains
+}
+
+// OnMessage processes incoming messages
+func (p *DomainBlockPlugin) OnMessage(msg *model.Message, config map[string]interface{}) []*model.MessageAction {
+	// Skip messages from bots
+	if msg.FromBot {
+		return nil
+	}
+
+	// Get blocked domains from config
+	blockedDomainsStr, ok := config["blocked_domains"].(string)
+	if !ok || blockedDomainsStr == "" {
+		return nil // No blocked domains configured
+	}
+
+	// Split and clean blocked domains
+	blockedDomains := strings.Split(blockedDomainsStr, ",")
+	for i, domain := range blockedDomains {
+		blockedDomains[i] = strings.ToLower(strings.TrimSpace(domain))
+	}
+
+	// Extract domains from message
+	messageDomains := extractDomains(msg.Text)
+	if len(messageDomains) == 0 {
+		return nil // No domains in message
+	}
+
+	// Check if any domains in the message are blocked
+	for _, msgDomain := range messageDomains {
+		for _, blockedDomain := range blockedDomains {
+			if blockedDomain == "" {
+				continue
+			}
+
+			if strings.HasSuffix(msgDomain, blockedDomain) || msgDomain == blockedDomain {
+				// Domain is blocked, create actions
+
+				// 1. Create a delete message action
+				deleteAction := &model.MessageAction{
+					Type:      model.ActionDeleteMessage,
+					MessageID: msg.ID,
+					Chat:      msg.Chat,
+					Channel:   msg.Channel,
+				}
+
+				// 2. Create a notification message action
+				notificationMsg := &model.Message{
+					Text:    fmt.Sprintf("I don't like links from %s 🙈", blockedDomain),
+					Chat:    msg.Chat,
+					Channel: msg.Channel,
+				}
+
+				sendAction := &model.MessageAction{
+					Type:    model.ActionSendMessage,
+					Message: notificationMsg,
+					Chat:    msg.Chat,
+					Channel: msg.Channel,
+				}
+
+				return []*model.MessageAction{deleteAction, sendAction}
+			}
+		}
+	}
+
+	return nil
+}
+
+// Plugin is registered in app.go, not using init()