import { describe, expect, it } from "bun:test";
import {
  adaptiveMaxTokens,
  conversationChars,
  ErrorTracker,
  truncateToolOutput,
} from "./turn_service.ts";
import { type ChatMessage, newConversation, systemMessage, userMessage, toolResultMessage } from "@zesdex/domain";

describe("truncateToolOutput", () => {
  it("short output is unchanged", () => {
    expect(truncateToolOutput("short")).toBe("short");
  });

  it("long output preserves head and marks cut", () => {
    const long = "x".repeat(12_000 + 500);
    const truncated = truncateToolOutput(long);
    expect(truncated.length).toBeLessThan(long.length);
    expect(truncated).toContain("...[truncated");
    expect(truncated.startsWith("xxx")).toBe(true);
  });
});

describe("adaptiveMaxTokens", () => {
  it("scales with request length", () => {
    expect(adaptiveMaxTokens(10)).toBe(800);
    expect(adaptiveMaxTokens(200)).toBe(1600);
    expect(adaptiveMaxTokens(5000)).toBe(4096);
  });
});

describe("ErrorTracker", () => {
  it("injects recovery note after repeated errors", () => {
    const tracker = new ErrorTracker();
    const messages: ChatMessage[] = [];
    tracker.record("read", "Error: File not found", messages);
    tracker.record("read", "Error: File not found", messages);
    expect(tracker.shouldStop()).toBe(false);
    tracker.record("read", "Error: File not found", messages);
    expect(messages.some((m) => m.content?.includes("[System note]"))).toBe(true);
  });

  it("stops after too many errors", () => {
    const tracker = new ErrorTracker();
    const messages: ChatMessage[] = [];
    for (let i = 0; i < 8; i++) {
      tracker.record("bash", `Error: boom ${i}`, messages);
    }
    expect(tracker.shouldStop()).toBe(true);
  });
});

describe("conversationChars", () => {
  it("sums content only", () => {
    const conv = newConversation("sys", "s1");
    conv.messages.push(systemMessage("sys"), userMessage("hello world"), toolResultMessage("id", "output"));
    expect(conversationChars(conv.messages)).toBe(3 + 11 + 6);
  });
});