/**
 * PDFExtractor Unit Tests
 */

import { describe, expect, test } from "bun:test";
import { sanitizeText, chunkText } from "./PDFExtractor.js";

// ============================================================================
// sanitizeText() Tests
// ============================================================================

describe("sanitizeText", () => {
  test("strips null bytes from text", () => {
    const input = "Hello\x00World\x00!";
    const result = sanitizeText(input);
    expect(result).toBe("HelloWorld!");
  });

  test("strips multiple consecutive null bytes", () => {
    const input = "Text\x00\x00\x00with\x00\x00nulls";
    const result = sanitizeText(input);
    expect(result).toBe("Textwithnulls");
  });

  test("handles text with no null bytes", () => {
    const input = "Clean text";
    const result = sanitizeText(input);
    expect(result).toBe("Clean text");
  });

  test("handles empty string", () => {
    const input = "";
    const result = sanitizeText(input);
    expect(result).toBe("");
  });

  test("handles string with only null bytes", () => {
    const input = "\x00\x00\x00";
    const result = sanitizeText(input);
    expect(result).toBe("");
  });

  test("preserves unicode characters", () => {
    const input = "café\x00naïve\x00résumé";
    const result = sanitizeText(input);
    expect(result).toBe("cafénaïverésumé");
  });

  test("strips null bytes before other processing", () => {
    // Verify that null bytes are removed early in the pipeline
    const input = "Text\x00with\x00null\x00bytes";
    const result = sanitizeText(input);
    // Should not contain null bytes
    expect(result).not.toContain("\x00");
    // Should preserve the rest
    expect(result).toBe("Textwithnullbytes");
  });
});

// ============================================================================
// chunkText() Tests
// ============================================================================

describe("chunkText", () => {
  test("preserves paragraph boundaries (does not collapse all whitespace)", () => {
    const input = [
      "Para 1 line one",
      "Para 1 line two",
      "",
      "Para 2 line one",
      "Para 2 line two",
      "",
    ].join("\n");

    const chunks = chunkText(input, 10_000, 0);
    expect(chunks).toHaveLength(1);
    expect(chunks[0]).toBe(
      "Para 1 line one Para 1 line two\n\nPara 2 line one Para 2 line two"
    );
  });

  test("removes common PDF hyphenation artifacts at line breaks", () => {
    const input = "This is inter-\nnational text.";
    const chunks = chunkText(input, 10_000, 0);
    expect(chunks).toHaveLength(1);
    expect(chunks[0]).toBe("This is international text.");
  });

  test("filters tiny chunks (<20 chars)", () => {
    const input = ["Short", "", "This is a longer paragraph that should remain."]
      .join("\n");
    const chunks = chunkText(input, 25, 0);
    // With the small chunk size, the long paragraph will be split or kept,
    // but the tiny "Short" paragraph should be filtered out.
    expect(chunks.join("\n")).not.toContain("Short");
  });
});