interstellar_ai/app/hooks/useChatHistory.tsx

94 lines
3.5 KiB
TypeScript

import { useEffect, useState } from "react";
// Define the structure of a Message
interface Message {
role: string; // The role of the message sender (e.g., system, user, assistant)
content: string; // The content of the message
}
// Define the structure for each chat session
interface ChatMessages {
name: string; // The name or title of the chat
messages: Message[]; // Array of messages in the chat
timestamp: number; // Timestamp for the chat session
}
// Define the structure for the global chat history
interface GlobalChatHistory {
chats: ChatMessages[]; // Array of chat sessions
selectedIndex: number; // Index of the currently selected chat
}
// Initial global chat history state
let globalChatHistory: GlobalChatHistory = {
chats: [
{
name: "Welcome!",
messages: [
{ role: "system", content: "you are a helpful assistant" },
{ role: "assistant", content: "Hello! How can I help you?" }
],
timestamp: 4
},
],
selectedIndex: 0
};
// Listeners for state changes
let listeners: ((state: GlobalChatHistory) => void)[] = [];
// Function to set a new global state and notify listeners
const setGlobalState = (newState: GlobalChatHistory): void => {
globalChatHistory = newState; // Update the global state
listeners.forEach((listener) => listener(globalChatHistory)); // Notify all listeners
}
// Custom hook to manage chat history
export const useChatHistory = (): [
GlobalChatHistory, // Current state
(newState: GlobalChatHistory) => void, // Function to set global state
] => {
const [state, setState] = useState<GlobalChatHistory>(globalChatHistory); // Local state initialized with global state
useEffect(() => {
// Listener to update local state when global state changes
const listener = (newState: GlobalChatHistory) => {
setState(newState);
};
listeners.push(listener); // Add the listener to the array
// Cleanup function to remove the listener when the component unmounts
return () => {
listeners = listeners.filter((l) => l !== listener);
};
}, []);
// Return the current state and action functions
return [state, setGlobalState];
}
// Function to set the selected chat index
export const setSelectedIndex = (index: number) => {
setGlobalState({ ...globalChatHistory, selectedIndex: index }); // Update the global state
}
// Function to update a specific message in the current chat
export const updateMessage = (messageIndex: number, newContent: string) => {
const updatedChats = [...globalChatHistory.chats]; // Make a copy of the current chats
const chatIndex = globalChatHistory.selectedIndex; // Get the currently selected chat index
// Check if the selected chat index is valid
if (chatIndex >= 0 && chatIndex < updatedChats.length) {
const updatedMessages = [...updatedChats[chatIndex].messages]; // Copy messages of the selected chat
// Check if the message index is valid
if (messageIndex >= 0 && messageIndex < updatedMessages.length) {
// Update the content of the specified message
updatedMessages[messageIndex] = { ...updatedMessages[messageIndex], content: newContent };
updatedChats[chatIndex] = { ...updatedChats[chatIndex], messages: updatedMessages }; // Update the chat with new messages
setGlobalState({ ...globalChatHistory, chats: updatedChats }); // Set the updated global state
}
}
}