fix removing roles from members (maybe)

src/discord/store.cpp

@@ -253,6 +253,14 @@ void Store::SetGuildMember(Snowflake guild_id, Snowflake user_id, const GuildMem
 
     s->Reset();
 
+    {
+        auto &s = m_stmt_clr_member_roles;
+        s->Bind(1, user_id);
+        s->Bind(2, guild_id);
+        s->Step();
+        s->Reset();
+    }
+
     {
         auto &s = m_stmt_set_member_roles;
 
@@ -1881,6 +1889,20 @@ bool Store::CreateStatements() {
         return false;
     }
 
+    m_stmt_clr_member_roles = std::make_unique<Statement>(m_db, R"(
+        DELETE FROM member_roles
+        WHERE user = ? AND
+        EXISTS (
+            SELECT 1 FROM roles
+            WHERE member_roles.role = roles.id
+            AND roles.guild = ?
+        )
+    )");
+    if (!m_stmt_clr_member_roles->OK()) {
+        fprintf(stderr, "failed to prepare clear member roles statement: %s\n", m_db.ErrStr());
+        return false;
+    }
+
     m_stmt_set_guild_emoji = std::make_unique<Statement>(m_db, R"(
         REPLACE INTO guild_emojis VALUES (
             ?, ?

src/discord/store.hpp

@@ -281,6 +281,7 @@ private:
     STMT(set_interaction);
     STMT(set_member_roles);
     STMT(get_member_roles);
+    STMT(clr_member_roles);
     STMT(set_guild_emoji);
     STMT(get_guild_emojis);
     STMT(clr_guild_emoji);