refactor: isolate chat hot paths and lazy server watchers

Split static history from live tail, stabilize chat data identities, and reduce scroll-shell churn so old viewport content stops waking on stream deltas. Also defer watcher startup and health polling so idle runtime work better matches actual usage.
2026-04-05 15:36:11 +03:00
parent fc44465c00
commit 4663abd6f3
17 changed files with 1053 additions and 306 deletions
@@ -23,6 +23,119 @@ export interface TurnWindowModel {
    turnCount: number;
 }

+const getMessageSignature = (message: ChatMessageEntry | undefined): string | null => {
+    if (!message) return null;
+    const role = resolveMessageRole(message);
+    const messageId = typeof message.info?.id === 'string' ? message.info.id : '';
+    const parentId = resolveParentMessageId(message) ?? '';
+    return `${messageId}::${role}::${parentId}`;
+};
+
+const cloneTurnWindowModel = (model: TurnWindowModel): TurnWindowModel => ({
+    turnIds: [...model.turnIds],
+    turnMessageStartIndexes: [...model.turnMessageStartIndexes],
+    turnIndexById: new Map(model.turnIndexById),
+    messageToTurnId: new Map(model.messageToTurnId),
+    messageToTurnIndex: new Map(model.messageToTurnIndex),
+    turnCount: model.turnCount,
+});
+
+export const updateTurnWindowModelIncremental = (
+    previousModel: TurnWindowModel | null,
+    previousMessages: ChatMessageEntry[] | null,
+    nextMessages: ChatMessageEntry[],
+): TurnWindowModel | null => {
+    if (!previousModel || !previousMessages) {
+        return null;
+    }
+
+    if (previousMessages.length === nextMessages.length) {
+        let changedIndex = -1;
+        for (let index = 0; index < nextMessages.length; index += 1) {
+            if (previousMessages[index] === nextMessages[index]) {
+                continue;
+            }
+            if (changedIndex !== -1) {
+                return null;
+            }
+            changedIndex = index;
+        }
+
+        if (changedIndex === -1) {
+            return previousModel;
+        }
+
+        if (changedIndex !== nextMessages.length - 1) {
+            return null;
+        }
+
+        return getMessageSignature(previousMessages[changedIndex]) === getMessageSignature(nextMessages[changedIndex])
+            ? previousModel
+            : null;
+    }
+
+    if (nextMessages.length !== previousMessages.length + 1) {
+        return null;
+    }
+
+    for (let index = 0; index < previousMessages.length; index += 1) {
+        if (previousMessages[index] !== nextMessages[index]) {
+            return null;
+        }
+    }
+
+    const nextMessage = nextMessages[nextMessages.length - 1];
+    if (!nextMessage) {
+        return null;
+    }
+
+    const role = resolveMessageRole(nextMessage);
+    const messageId = nextMessage.info.id;
+    const nextModel = cloneTurnWindowModel(previousModel);
+
+    if (role === 'user') {
+        const nextTurnIndex = nextModel.turnIds.length;
+        nextModel.turnIds.push(messageId);
+        nextModel.turnMessageStartIndexes.push(nextMessages.length - 1);
+        nextModel.turnIndexById.set(messageId, nextTurnIndex);
+        nextModel.messageToTurnId.set(messageId, messageId);
+        nextModel.messageToTurnIndex.set(messageId, nextTurnIndex);
+        nextModel.turnCount = nextModel.turnIds.length;
+        return nextModel;
+    }
+
+    if (role !== 'assistant') {
+        const currentTurnIndex = nextModel.turnIds.length - 1;
+        if (currentTurnIndex < 0) {
+            return null;
+        }
+        const turnId = nextModel.turnIds[currentTurnIndex];
+        if (!turnId) {
+            return null;
+        }
+        nextModel.messageToTurnId.set(messageId, turnId);
+        nextModel.messageToTurnIndex.set(messageId, currentTurnIndex);
+        return nextModel;
+    }
+
+    const parentId = resolveParentMessageId(nextMessage);
+    const targetTurnIndex = parentId
+        ? nextModel.turnIndexById.get(parentId)
+        : nextModel.turnIds.length - 1;
+    if (typeof targetTurnIndex !== 'number' || targetTurnIndex < 0) {
+        return null;
+    }
+
+    const turnId = nextModel.turnIds[targetTurnIndex];
+    if (!turnId) {
+        return null;
+    }
+
+    nextModel.messageToTurnId.set(messageId, turnId);
+    nextModel.messageToTurnIndex.set(messageId, targetTurnIndex);
+    return nextModel;
+};
+
 export const buildTurnWindowModel = (messages: ChatMessageEntry[]): TurnWindowModel => {
    const turnIds: string[] = [];
    const turnMessageStartIndexes: number[] = [];