From be3d1edcae07035ff53d60306bb6b9a37d1593eb Mon Sep 17 00:00:00 2001
From: Guangcong Luo <guangcongluo@gmail.com>
Date: Fri, 5 Dec 2025 08:43:33 +0000
Subject: [PATCH] Preact: Fix format normalization

Fixes #2552
---
 play.pokemonshowdown.com/src/battle-log.ts  | 11 +++++++++++
 play.pokemonshowdown.com/src/panel-chat.tsx |  3 +--
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/play.pokemonshowdown.com/src/battle-log.ts b/play.pokemonshowdown.com/src/battle-log.ts
index c39f2beb4..1438a37d6 100644
--- a/play.pokemonshowdown.com/src/battle-log.ts
+++ b/play.pokemonshowdown.com/src/battle-log.ts
@@ -1086,6 +1086,17 @@ export class BattleLog {
 		}
 		return this.escapeHTML(this.formatName(formatid, fixGen6));
 	}
+	static formatId(format: string): ID {
+		const atIndex = format.indexOf('@@@');
+		if (atIndex >= 0) {
+			format = toID(format.slice(0, atIndex)) + format.slice(atIndex).trim();
+		} else {
+			format = toID(format);
+		}
+		if (!format) return '' as ID;
+		if (!format.startsWith('gen')) format = `${Dex.modid}${format}`;
+		return format as ID;
+	}
 	/**
 	 * Do not store this output anywhere; it removes the generation number
 	 * for the current gen.
diff --git a/play.pokemonshowdown.com/src/panel-chat.tsx b/play.pokemonshowdown.com/src/panel-chat.tsx
index d788a7c38..75379be50 100644
--- a/play.pokemonshowdown.com/src/panel-chat.tsx
+++ b/play.pokemonshowdown.com/src/panel-chat.tsx
@@ -313,8 +313,7 @@ export class ChatRoom extends PSRoom {
 					format = target;
 					targetUser = this.pmTarget;
 				}
-				format = (format || '').trim();
-				if (!format.startsWith('gen')) format = `${Dex.modid}${format}`;
+				format = BattleLog.formatId(format || '');
 				PS.mainmenu.makeQuery('userdetails', targetUser).then(data => {
 					if (data.rooms === false) return this.errorReply('This player does not exist or is not online.');
 					PS.join(`challenge-${toID(targetUser)}` as RoomID, { args: { format } });