fix edited Discord messages not updating in database

logMessage now upserts content on conflict instead of INSERT OR IGNORE,
so backfill picks up edited messages. Added messageUpdate event handler
to capture edits in real-time. This fixes student stats showing 0 PRs
when students edit their EOD messages to add PR links.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: dsshimel

attendabot/backend/src/services/db.ts

@@ -290,8 +290,10 @@ export function logMessage(message: MessageRecord): void {
   upsertUser(message.author_id, message.display_name, message.username);
 
   const stmt = db.prepare(`
-    INSERT OR IGNORE INTO messages (discord_message_id, channel_id, author_id, content, created_at)
+    INSERT INTO messages (discord_message_id, channel_id, author_id, content, created_at)
     VALUES (?, ?, ?, ?, ?)
+    ON CONFLICT(discord_message_id) DO UPDATE SET
+      content = excluded.content
   `);
   stmt.run(
     message.discord_message_id,

attendabot/backend/src/services/discord.ts

@@ -186,6 +186,31 @@ export async function initializeDiscord(): Promise<Client> {
         }
       });
 
+      // Register messageUpdate listener to capture edited messages
+      discordClient.on("messageUpdate", async (_oldMessage, newMessage) => {
+        if (!MONITORED_CHANNEL_IDS.includes(newMessage.channelId)) return;
+        if (newMessage.author?.bot) return;
+
+        try {
+          // Fetch full message if partial (not in cache)
+          const message = newMessage.partial ? await newMessage.fetch() : newMessage;
+          const channel = message.channel as TextChannel;
+          logMessage({
+            discord_message_id: message.id,
+            channel_id: message.channelId,
+            channel_name: channel.name,
+            author_id: message.author.id,
+            display_name: message.member?.displayName || null,
+            username: message.author.username,
+            content: message.content,
+            created_at: message.createdAt.toISOString(),
+          });
+          console.log(`Updated edited message from ${message.author.username} in #${channel.name}`);
+        } catch (error) {
+          console.error("Failed to update edited message:", error);
+        }
+      });
+
       // Run backfill after ready
       backfillMonitoredChannels(discordClient).catch((error) => {
         console.error("Failed to backfill monitored channels", error);

attendabot/backend/src/test/services/db.test.ts

@@ -134,6 +134,36 @@ describe("Database Service - Direct Tests", () => {
       expect(result.count).toBe(1);
     });
 
+    it("updates content on duplicate discord_message_id via upsert", () => {
+      const channel = createTestChannel(db);
+      const user = createTestUser(db);
+
+      createTestMessage(db, {
+        discordMessageId: "msg-1",
+        channelId: channel.channel_id,
+        authorId: user.author_id,
+        content: "Original content",
+      });
+
+      // Re-insert with updated content (simulates logMessage upsert after edit)
+      const stmt = db.prepare(`
+        INSERT INTO messages (discord_message_id, channel_id, author_id, content, created_at)
+        VALUES (?, ?, ?, ?, ?)
+        ON CONFLICT(discord_message_id) DO UPDATE SET
+          content = excluded.content
+      `);
+      stmt.run("msg-1", channel.channel_id, user.author_id, "Edited with PRs", new Date().toISOString());
+
+      const row = db.prepare("SELECT content FROM messages WHERE discord_message_id = ?")
+        .get("msg-1") as { content: string };
+
+      expect(row.content).toBe("Edited with PRs");
+
+      const countResult = db.prepare("SELECT COUNT(*) as count FROM messages")
+        .get() as { count: number };
+      expect(countResult.count).toBe(1);
+    });
+
     it("retrieves messages ordered by newest first", () => {
       const channel = createTestChannel(db);
       const user = createTestUser(db);