Changeset 0.23.2 (#155)

server/handlers/participants.go

@@ -6,6 +6,7 @@ import (
 
 	"github.com/gin-gonic/gin"
 
+	"git.gobha.me/xcaliber/chat-switchboard/database"
 	"git.gobha.me/xcaliber/chat-switchboard/models"
 	"git.gobha.me/xcaliber/chat-switchboard/store"
 )
@@ -258,6 +259,37 @@ func (h *ParticipantHandler) Remove(c *gin.Context) {
 		}
 	}
 
+	// v0.23.2: DM guard — cannot drop below 2 human participants
+	var channelType string
+	_ = database.DB.QueryRowContext(c.Request.Context(), database.Q(`
+		SELECT COALESCE(type, 'direct') FROM channels WHERE id = $1
+	`), channelID).Scan(&channelType)
+
+	if channelType == "dm" && p.ParticipantType == "user" {
+		var userCount int
+		_ = database.DB.QueryRowContext(c.Request.Context(), database.Q(`
+			SELECT COUNT(*) FROM channel_participants
+			WHERE channel_id = $1 AND participant_type = 'user'
+		`), channelID).Scan(&userCount)
+		if userCount <= 2 {
+			c.JSON(http.StatusConflict, gin.H{"error": "DMs require at least 2 participants"})
+			return
+		}
+	}
+
+	// v0.23.2: Group guard — cannot remove the last persona
+	if channelType == "group" && p.ParticipantType == "persona" {
+		var personaCount int
+		_ = database.DB.QueryRowContext(c.Request.Context(), database.Q(`
+			SELECT COUNT(*) FROM channel_participants
+			WHERE channel_id = $1 AND participant_type = 'persona'
+		`), channelID).Scan(&personaCount)
+		if personaCount <= 1 {
+			c.JSON(http.StatusConflict, gin.H{"error": "group chats require at least 1 persona"})
+			return
+		}
+	}
+
 	// If removing a persona, also remove its auto-created model roster entry
 	if p.ParticipantType == "persona" {
 		_ = h.stores.Channels.DeleteModelByPersona(c.Request.Context(), channelID, p.ParticipantID)