Add LLM chat history widget (#3907)

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src/composables/node/useNodeChatHistory.ts

@@ -0,0 +1,60 @@
+import { LGraphNode } from '@comfyorg/litegraph'
+
+import type ChatHistoryWidget from '@/components/graph/widgets/ChatHistoryWidget.vue'
+import { useChatHistoryWidget } from '@/composables/widgets/useChatHistoryWidget'
+
+const CHAT_HISTORY_WIDGET_NAME = '$$node-chat-history'
+
+/**
+ * Composable for handling node text previews
+ */
+export function useNodeChatHistory(
+  options: {
+    minHeight?: number
+    props?: Omit<InstanceType<typeof ChatHistoryWidget>['$props'], 'widget'>
+  } = {}
+) {
+  const chatHistoryWidget = useChatHistoryWidget(options)
+
+  const findChatHistoryWidget = (node: LGraphNode) =>
+    node.widgets?.find((w) => w.name === CHAT_HISTORY_WIDGET_NAME)
+
+  const addChatHistoryWidget = (node: LGraphNode) =>
+    chatHistoryWidget(node, {
+      name: CHAT_HISTORY_WIDGET_NAME,
+      type: 'chatHistory'
+    })
+
+  /**
+   * Shows chat history for a node
+   * @param node The graph node to show the chat history for
+   */
+  function showChatHistory(node: LGraphNode) {
+    if (!findChatHistoryWidget(node)) {
+      addChatHistoryWidget(node)
+    }
+    node.setDirtyCanvas?.(true)
+  }
+
+  /**
+   * Removes chat history from a node
+   * @param node The graph node to remove the chat history from
+   */
+  function removeChatHistory(node: LGraphNode) {
+    if (!node.widgets) return
+
+    const widgetIdx = node.widgets.findIndex(
+      (w) => w.name === CHAT_HISTORY_WIDGET_NAME
+    )
+
+    if (widgetIdx > -1) {
+      node.widgets[widgetIdx].onRemove?.()
+      node.widgets.splice(widgetIdx, 1)
+    }
+  }
+
+  return {
+    showChatHistory,
+    removeChatHistory
+  }
+}