Files
arubinochan-bot/lib/llm.ts
2025-10-02 16:30:11 +00:00

79 lines
1.8 KiB
TypeScript

import path from "node:path";
import { fileURLToPath } from "node:url";
import {
type ChatHistoryItem,
type LLamaChatPromptOptions,
LlamaChatSession,
type LlamaModel,
createModelDownloader,
getLlama,
resolveChatWrapper,
} from "node-llama-cpp";
const __dirname = path.dirname(fileURLToPath(import.meta.url));
export async function getModel(model: string) {
const downloader = await createModelDownloader({
modelUri: `hf:${model}`,
dirPath: path.join(__dirname, "..", "models"),
});
const modelPath = await downloader.download();
const llama = await getLlama({
maxThreads: 2,
});
return await llama.loadModel({ modelPath });
}
export type Message = {
type: "system" | "model" | "user";
text: string;
};
export async function complete(
model: LlamaModel,
messages: Message[],
options: LLamaChatPromptOptions = {},
) {
if (messages.length < 1) throw new Error("messages are empty");
const init = messages.slice(0, -1);
const last = messages.at(-1) as Message;
const context = await model.createContext();
const session = new LlamaChatSession({
contextSequence: context.getSequence(),
chatWrapper: resolveChatWrapper(model),
});
session.setChatHistory(
init.map((m): ChatHistoryItem => {
switch (m.type) {
case "system":
return {
type: "system",
text: m.text,
};
case "model":
return {
type: "model",
response: [m.text],
};
case "user":
return {
type: "user",
text: m.text,
};
}
}),
);
const res = await session.prompt(last.text, {
trimWhitespaceSuffix: true,
onResponseChunk(chunk) {
process.stderr.write(chunk.text);
},
...options,
});
session.dispose();
await context.dispose();
return res;
}