import { describe, expect, it } from "vitest";
import {
  ASSISTANT_MARKER,
  STREAMING_CURSOR,
  USER_MARKER,
  buildThreadMarkdown,
  previewText,
  quote,
  sessionToPlainText,
} from "../lib/markdown";
import type { ChatTurn, ThreadMessage } from "../lib/types";

function message(overrides: Partial<ThreadMessage> & Pick<ThreadMessage, "role">): ThreadMessage {
  return {
    id: "m1",
    text: "",
    preview: "",
    createdAt: 0,
    isStreaming: false,
    thinking: "",
    toolCalls: [],
    ...overrides,
  };
}

describe("quote", () => {
  it("keeps a multi-line message inside one quote block", () => {
    expect(quote("line one\nline two")).toBe("> line one\n> line two");
  });
});

describe("buildThreadMarkdown", () => {
  it("returns nothing for an empty conversation", () => {
    expect(buildThreadMarkdown([])).toBe("");
  });

  it("renders a question as a quote and an answer as body text", () => {
    const markdown = buildThreadMarkdown([
      message({ role: "user", text: "What is 2+2?" }),
      message({ role: "assistant", text: "4" }),
    ]);

    expect(markdown).toContain("**You**");
    expect(markdown).toContain("> What is 2+2?");
    expect(markdown).toContain("**Lam**");
    expect(markdown).toContain("4");
  });

  it("marks each speaker with a role icon", () => {
    const markdown = buildThreadMarkdown([
      message({ role: "user", text: "q" }),
      message({ role: "assistant", text: "a" }),
    ]);

    expect(markdown).toContain(USER_MARKER);
    expect(markdown).toContain(ASSISTANT_MARKER);
    // The user marker must not leak onto the answer or vice versa.
    expect(markdown.indexOf(USER_MARKER)).toBeLessThan(markdown.indexOf(ASSISTANT_MARKER));
  });

  it("keeps the conversation in order", () => {
    const markdown = buildThreadMarkdown([
      message({ id: "a", role: "user", text: "first" }),
      message({ id: "b", role: "assistant", text: "second" }),
      message({ id: "c", role: "user", text: "third" }),
    ]);

    expect(markdown.indexOf("first")).toBeLessThan(markdown.indexOf("second"));
    expect(markdown.indexOf("second")).toBeLessThan(markdown.indexOf("third"));
  });

  it("marks a streaming answer with a cursor", () => {
    const streaming = buildThreadMarkdown([
      message({ role: "assistant", text: "partial", isStreaming: true }),
    ]);
    const finished = buildThreadMarkdown([message({ role: "assistant", text: "partial" })]);

    expect(streaming).toContain(STREAMING_CURSOR);
    expect(finished).not.toContain(STREAMING_CURSOR);
  });

  it("shows a placeholder while an answer has no text yet", () => {
    expect(buildThreadMarkdown([message({ role: "assistant", isStreaming: true })])).toContain("Thinking");
    expect(buildThreadMarkdown([message({ role: "assistant" })])).toContain("No response");
  });

  it("surfaces an error instead of hiding it", () => {
    const markdown = buildThreadMarkdown([
      message({ role: "assistant", error: "Ollama rejected the API key." }),
    ]);
    expect(markdown).toContain("Ollama rejected the API key.");
  });

  it("lists tools that were used, flagging failures", () => {
    const markdown = buildThreadMarkdown([
      message({
        role: "assistant",
        text: "a",
        toolCalls: [
          { name: "web_search", arguments: {}, result: "ok", isError: false },
          { name: "web_fetch", arguments: {}, result: "boom", isError: true },
        ],
      }),
    ]);

    expect(markdown).toContain("`web_search`");
    expect(markdown).toContain("`web_fetch` — failed");
  });

  it("only shows a reasoning section when there is reasoning", () => {
    expect(buildThreadMarkdown([message({ role: "assistant", text: "a" })])).not.toContain("Reasoning");
    expect(buildThreadMarkdown([message({ role: "assistant", text: "a", thinking: "hmm" })])).toContain(
      "Reasoning",
    );
  });
});

describe("previewText", () => {
  it("collapses newlines so a preview stays on one row", () => {
    expect(previewText("a\n\nb", 40)).toBe("a b");
  });

  it("clips with an ellipsis", () => {
    expect(previewText("a".repeat(50), 5)).toHaveLength(5);
  });

  it("leaves short text alone", () => {
    expect(previewText("hi", 40)).toBe("hi");
  });
});

describe("sessionToPlainText", () => {
  function turn(prompt: string, response: string, error?: string): ChatTurn {
    return { id: prompt, prompt, response, thinking: "", model: "m", createdAt: 0, toolCalls: [], error };
  }

  it("returns an empty string for an empty conversation", () => {
    expect(sessionToPlainText([])).toBe("");
  });

  it("keeps every question and answer", () => {
    const text = sessionToPlainText([turn("q1", "a1"), turn("q2", "a2")]);

    expect(text).toContain("## q1");
    expect(text).toContain("a1");
    expect(text).toContain("## q2");
    expect(text).toContain("a2");
  });

  it("includes the failure when a turn errored", () => {
    expect(sessionToPlainText([turn("q", "", "Ollama rejected the API key.")])).toContain(
      "Ollama rejected the API key.",
    );
  });
});