import { describe, expect, it } from "vitest";
import remend from "..";

describe("chunked streaming scenarios", () => {
  it("should handle nested formatting cut mid-stream", () => {
    expect(remend("This is **bold with *ital")).toBe(
      "This is **bold with *ital*"
    );
    // When bold is unclosed, it gets closed first, then underscore
    expect(remend("**bold _und")).toBe("**bold _und**_");
  });

  it("should handle headings with incomplete formatting", () => {
    expect(remend("# Main Title\n## Subtitle with **emph")).toBe(
      "# Main Title\n## Subtitle with **emph**"
    );
  });

  it("should handle blockquotes with incomplete formatting", () => {
    expect(remend("> Quote with **bold")).toBe("> Quote with **bold**");
  });

  it("should handle tables with incomplete formatting", () => {
    expect(remend("| Col1 | Col2 |\n|------|------|\n| **dat")).toBe(
      "| Col1 | Col2 |\n|------|------|\n| **dat**"
    );
  });

  it("should handle complex nested structures from chunks", () => {
    // Backticks spanning multiple lines need special handling
    expect(remend("1. First item\n   - Nested with `code\n2. Second")).toBe(
      "1. First item\n   - Nested with `code\n2. Second`"
    );
  });

  it("should handle multiple incomplete formats in one chunk", () => {
    // Formats are closed in order they're processed
    expect(remend("Text **bold `code")).toBe("Text **bold `code**`");
  });
});

describe("real-world streaming chunks", () => {
  it("should handle typical GPT response chunks", () => {
    const chunks = [
      "Here is",
      "Here is a **bold",
      "Here is a **bold statement",
      "Here is a **bold statement** about",
      "Here is a **bold statement** about `code",
      "Here is a **bold statement** about `code`.",
    ];

    expect(remend(chunks[0])).toBe("Here is");
    expect(remend(chunks[1])).toBe("Here is a **bold**");
    expect(remend(chunks[2])).toBe("Here is a **bold statement**");
    expect(remend(chunks[3])).toBe("Here is a **bold statement** about");
    expect(remend(chunks[4])).toBe("Here is a **bold statement** about `code`");
    expect(remend(chunks[5])).toBe(chunks[5]);
  });

  it("should handle code explanation chunks", () => {
    const chunks = [
      "To use this function",
      "To use this function, call `getData(",
      "To use this function, call `getData()` with",
    ];

    expect(remend(chunks[0])).toBe(chunks[0]);
    expect(remend(chunks[1])).toBe("To use this function, call `getData(`");
    expect(remend(chunks[2])).toBe(chunks[2]);
  });
});