import { test } from "node:test";

import assert from "node:assert/strict";

import { findExpandedThinkingId } from "../ui";

import type { SessionMessage } from "../session";

function buildMessage(

id: string,

role: SessionMessage["role"],

options: { asThinking?: boolean } = {}

): SessionMessage {

return {

id,

sessionId: "s",

role,

content: "",

contentParams: null,

messageParams: null,

compacted: false,

visible: true,

createTime: "2026-04-28T00:00:00.000Z",

updateTime: "2026-04-28T00:00:00.000Z",

meta: options.asThinking ? { asThinking: true } : undefined,

};

}

test("findExpandedThinkingId returns null on an empty list", () => {

assert.equal(findExpandedThinkingId([]), null);

});

test("findExpandedThinkingId returns the only thinking id when there is no final reply", () => {

const messages = [buildMessage("user", "user"), buildMessage("a-1", "assistant", { asThinking: true })];

assert.equal(findExpandedThinkingId(messages), "a-1");

});

test("findExpandedThinkingId always picks the latest thinking id", () => {

const messages = [

buildMessage("a-1", "assistant", { asThinking: true }),

buildMessage("tool", "tool"),

buildMessage("a-2", "assistant", { asThinking: true }),

];

assert.equal(findExpandedThinkingId(messages), "a-2");

});

test("findExpandedThinkingId returns null after a non-thinking assistant reply", () => {

const messages = [buildMessage("a-1", "assistant", { asThinking: true }), buildMessage("a-final", "assistant")];

assert.equal(findExpandedThinkingId(messages), null);

});

test("findExpandedThinkingId picks the thinking id that follows the last final reply", () => {

const messages = [

buildMessage("a-1", "assistant", { asThinking: true }),

buildMessage("a-final", "assistant"),

buildMessage("a-2", "assistant", { asThinking: true }),

buildMessage("a-3", "assistant", { asThinking: true }),

];

assert.equal(findExpandedThinkingId(messages), "a-3");

});