import { describe, expect, it, vi } from "vitest";
import { subscribeEmbeddedPiSession } from "./pi-embedded-subscribe.js";

type StubSession = {
  subscribe: (fn: (evt: unknown) => void) => () => void;
};

describe("subscribeEmbeddedPiSession", () => {
  it("does not duplicate when text_end repeats full content", () => {
    let handler: ((evt: unknown) => void) | undefined;
    const session: StubSession = {
      subscribe: (fn) => {
        handler = fn;
        return () => {};
      },
    };

    const onBlockReply = vi.fn();

    const subscription = subscribeEmbeddedPiSession({
      session: session as unknown as Parameters<typeof subscribeEmbeddedPiSession>[0]["session"],
      runId: "run",
      onBlockReply,
      blockReplyBreak: "text_end",
    });

    handler?.({
      type: "message_update",
      message: { role: "assistant" },
      assistantMessageEvent: {
        type: "text_delta",
        delta: "Good morning!",
      },
    });

    handler?.({
      type: "message_update",
      message: { role: "assistant" },
      assistantMessageEvent: {
        type: "text_end",
        content: "Good morning!",
      },
    });

    expect(onBlockReply).toHaveBeenCalledTimes(1);
    expect(subscription.assistantTexts).toEqual(["Good morning!"]);
  });
  it("does not duplicate block chunks when text_end repeats full content", () => {
    let handler: ((evt: unknown) => void) | undefined;
    const session: StubSession = {
      subscribe: (fn) => {
        handler = fn;
        return () => {};
      },
    };

    const onBlockReply = vi.fn();

    subscribeEmbeddedPiSession({
      session: session as unknown as Parameters<typeof subscribeEmbeddedPiSession>[0]["session"],
      runId: "run",
      onBlockReply,
      blockReplyBreak: "text_end",
      blockReplyChunking: {
        minChars: 5,
        maxChars: 40,
        breakPreference: "newline",
      },
    });

    const fullText = "First line\nSecond line\nThird line\n";

    handler?.({
      type: "message_update",
      message: { role: "assistant" },
      assistantMessageEvent: {
        type: "text_delta",
        delta: fullText,
      },
    });

    const callsAfterDelta = onBlockReply.mock.calls.length;
    expect(callsAfterDelta).toBeGreaterThan(0);

    handler?.({
      type: "message_update",
      message: { role: "assistant" },
      assistantMessageEvent: {
        type: "text_end",
        content: fullText,
      },
    });

    expect(onBlockReply).toHaveBeenCalledTimes(callsAfterDelta);
  });
});
