[ADD/WIP] Start processing event relations

Schema/Relation.json

@@ -0,0 +1,19 @@
+{
+    "guard": "TELODENDRIA_SCHEMA_RELATION_H",
+    "header": "Schema/Relation.h",
+    "types": {
+        "Relation": {
+            "type": "struct",
+            "fields": {
+                "event_id": {
+                    "type": "string",
+                    "required": true
+                },
+                "rel_type": {
+                    "type": "string",
+                    "required": true
+                }
+            }
+        }
+    }
+}

src/Room/V1/Send.c

@@ -1,5 +1,6 @@
 #include "Room/internal.h"
 
+#include <Schema/Relation.h>
 #include <Schema/PduV1.h>
 
 #include <Parser.h>
@@ -312,6 +313,9 @@ RoomAddEventV1(Room *room, PduV1 pdu, PduV1Status status)
      * notified about. */
     if (status == PDUV1_STATUS_ACCEPTED)
     {
+        HashMap *relates_to = 
+            JsonValueAsObject(HashMapGet(pdu.content, "m.relates_to"));
+        Relation rel = { 0 };
         State *state;
         char *type, *state_key, *event_id;
 
@@ -319,6 +323,34 @@ RoomAddEventV1(Room *room, PduV1 pdu, PduV1Status status)
 
         /* If we have a membership change, then add it to the
          * proper table. */
+        if (RelationFromJson(relates_to, &rel, NULL))
+        {
+            DbRef *relate = DbLock(
+                room->db, 
+                4, "rooms", room->id, "events", rel.event_id
+            );
+            HashMap *relObj = DbJson(relate);
+            if (relObj)
+            {
+                Array *relList = JsonValueAsArray(HashMapGet(
+                    relObj, "relations"
+                ));
+                if (!relList)
+                {
+                    relList = ArrayCreate();
+                    JsonValueFree(HashMapSet(
+                        relObj, "relations", JsonValueArray(relList)
+                    ));
+                }
+
+                /* TODO: We may want to treat the relation as 'special' 
+                 * if the specification asks us to bundle it. */
+                ArrayAdd(relList, JsonValueString(pdu.event_id));
+            }
+
+            RelationFree(&rel);
+            DbUnlock(room->db, relate);
+        }
         if (StrEquals(pdu.type, "m.room.member"))
         {
             CommonID *id = UserIdParse(pdu.state_key, NULL);