diff --git a/src/chat/chat_event.c b/src/chat/chat_event.c
index 4ecceabb..5625c329 100644
--- a/src/chat/chat_event.c
+++ b/src/chat/chat_event.c
@@ -9,6 +9,8 @@
 #include "chat_event.h"
 #include "../utun_instance.h"
 #include "../lib/debug_config.h"
+#include <stdio.h>
+#include <string.h>
 
 #ifdef __ANDROID__
 #include <android/log.h>
@@ -47,8 +49,21 @@ void chat_event_post(struct UTUN_INSTANCE* inst, int type, const uint8_t* data,
         [40]="CALL_ERROR", [41]="DM_MESSAGES", [42]="CALL_PATH",
         [43]="RADIO_TALK",
         [44]="CALL_CONNECTION",
+        [45]="DM_CONVERSATIONS", [46]="ATTACHMENT_PREPARATION",
     };
     const char* n = (type >= 1 && type < (int)(sizeof(names) / sizeof(names[0]))) ? names[type] : "?";
     DEBUG_DEBUG(DEBUG_CATEGORY_CHAT, "chat_event: %s(%d) data=%d bytes", n, type, len);
     if (data && len > 0) log_dump(DEBUG_LEVEL_DEBUG, DEBUG_CATEGORY_CHAT, "  ", data, len);
 }
+
+/* ID задачи не даёт позднему завершению изменить статус другой подготовки. */
+void chat_event_attachment(struct UTUN_INSTANCE* inst, int is_dm, const char* target, const uint8_t id[16], int state) {
+    char name[68];
+    int n = snprintf(name, sizeof(name), "%s%s", is_dm ? "dm:" : "", target);
+    if (n <= 0 || (size_t)n >= sizeof(name) || state < 0 || state > 2) {
+        DEBUG_ERROR(DEBUG_CATEGORY_MEDIA, "attachment: invalid preparation event target=%s state=%d", target, state); return;
+    }
+    uint8_t data[1 + 68 + 16 + 1];
+    data[0] = (uint8_t)n; memcpy(data + 1, name, (size_t)n); memcpy(data + 1 + n, id, 16); data[17 + n] = (uint8_t)state;
+    chat_event_post(inst, CHAT_EVT_ATTACHMENT_PREPARATION, data, n + 18);
+}
diff --git a/src/chat/chat_event.h b/src/chat/chat_event.h
index 898eb400..4093c9f0 100644
--- a/src/chat/chat_event.h
+++ b/src/chat/chat_event.h
@@ -66,11 +66,13 @@ extern "C" {
 #define CHAT_EVT_RADIO_TALK         43  /* [group_id:8][src_node_id:8][stream_id:2][on:1] — кто-то начал/закончил говорить */
 #define CHAT_EVT_CALL_CONNECTION    44  /* [call_id:8][CONN_TYPE:1][next_hop_node_id:8] — текущий путь отправки звонка */
 #define CHAT_EVT_DM_CONVERSATIONS   45  /* [JSON:utf8] — последние 200 личных бесед */
+#define CHAT_EVT_ATTACHMENT_PREPARATION 46 /* [target_len:1][target:var][job_uuid:16][state:1], 0=start 1=ready 2=failed */
 
 typedef void (*chat_event_handler_fn)(struct UTUN_INSTANCE* inst, int type, const uint8_t* data, int len);
 
 void chat_event_set_handler(struct UTUN_INSTANCE* inst, chat_event_handler_fn handler);
 void chat_event_post(struct UTUN_INSTANCE* inst, int type, const uint8_t* data, int len);
+void chat_event_attachment(struct UTUN_INSTANCE* inst, int is_dm, const char* target, const uint8_t id[16], int state);
 
 #ifdef __cplusplus
 }