import { describe, expect, it } from "bun:test";
import { mapAgentSessionEventToAcpSessionUpdates } from "../src/modes/acp/acp-event-mapper";
import type { AgentSessionEvent } from "../src/session/agent-session";

function makeAssistantMessage(text: string) {
	return {
		role: "assistant" as const,
		content: [{ type: "text" as const, text }],
		api: "anthropic-messages" as const,
		provider: "anthropic" as const,
		model: "claude-sonnet-4-20250514",
		usage: {
			input: 10,
			output: 5,
			cacheRead: 0,
			cacheWrite: 0,
			totalTokens: 15,
			cost: { input: 0, output: 0, cacheRead: 0, cacheWrite: 0, total: 0 },
		},
		stopReason: "stop" as const,
		timestamp: Date.now(),
	};
}

function getChunkMessageId(event: { update: object }): string | undefined {
	const update = event.update as { messageId?: string | null };
	return typeof update.messageId === "string" ? update.messageId : undefined;
}

describe("ACP event mapper", () => {
	it("attaches a stable messageId to live assistant chunks", () => {
		const assistantMessage = makeAssistantMessage("chunk");
		const getMessageId = (message: unknown): string | undefined =>
			message === assistantMessage ? "a80f1ff7-4f0a-4e6b-9f09-c94857b62a4a" : undefined;

		const textUpdates = mapAgentSessionEventToAcpSessionUpdates(
			{
				type: "message_update",
				message: assistantMessage,
				assistantMessageEvent: { type: "text_delta", delta: "chunk" },
			} as AgentSessionEvent,
			"session-1",
			{ getMessageId },
		);
		const thoughtUpdates = mapAgentSessionEventToAcpSessionUpdates(
			{
				type: "message_update",
				message: assistantMessage,
				assistantMessageEvent: { type: "thinking_delta", delta: "plan" },
			} as AgentSessionEvent,
			"session-1",
			{ getMessageId },
		);

		expect(textUpdates).toHaveLength(1);
		expect(thoughtUpdates).toHaveLength(1);
		expect(textUpdates[0] ? getChunkMessageId(textUpdates[0]) : undefined).toBe(
			"a80f1ff7-4f0a-4e6b-9f09-c94857b62a4a",
		);
		expect(thoughtUpdates[0] ? getChunkMessageId(thoughtUpdates[0]) : undefined).toBe(
			"a80f1ff7-4f0a-4e6b-9f09-c94857b62a4a",
		);
	});
});