import { describe, expect, test } from "bun:test";
import { createTerminal, disposeTerminal, serializeAsHTML } from "./terminal";

// Helper to write to terminal and wait for completion
function writeSync(
  term: ReturnType<typeof createTerminal>,
  data: string,
): Promise<void> {
  return new Promise((resolve) => {
    term.terminal.write(data, resolve);
  });
}

describe("terminal", () => {
  test("creates terminal with correct dimensions", () => {
    const term = createTerminal(80, 24);
    expect(term.terminal.cols).toBe(80);
    expect(term.terminal.rows).toBe(24);
    disposeTerminal(term);
  });

  test("writes data to terminal buffer", async () => {
    const term = createTerminal(80, 24);
    await writeSync(term, "Hello, world!");
    const html = serializeAsHTML(term);
    expect(html).toContain("Hello, world!");
    disposeTerminal(term);
  });

  test("handles ANSI cursor movement", async () => {
    const term = createTerminal(80, 24);
    await writeSync(term, "AAA\x1b[3D"); // Write AAA, move cursor back 3
    await writeSync(term, "BBB"); // Overwrite with BBB
    const html = serializeAsHTML(term);
    expect(html).toContain("BBB");
    expect(html).not.toContain("AAA");
    disposeTerminal(term);
  });

  test("handles carriage return correctly", async () => {
    const term = createTerminal(80, 24);
    await writeSync(term, "Old text\rNew"); // CR should move to col 0
    const html = serializeAsHTML(term);
    expect(html).toContain("New");
    expect(html).not.toContain("Old");
    disposeTerminal(term);
  });

  test("handles incomplete ANSI sequences across writes", async () => {
    const term = createTerminal(80, 24);
    await writeSync(term, "Hello\x1b["); // Incomplete CSI
    await writeSync(term, "31mRed\x1b[0m"); // Complete it
    const html = serializeAsHTML(term);
    expect(html).toContain("Red");
    // Check for red styling (color may vary in format)
    expect(html).toMatch(/color|red|#[a-f0-9]{6}/i);
    disposeTerminal(term);
  });

  test("handles screen clearing", async () => {
    const term = createTerminal(80, 24);
    await writeSync(term, "First line\n");
    await writeSync(term, "Second line");
    await writeSync(term, "\x1b[2J"); // Clear screen
    await writeSync(term, "\x1b[H"); // Cursor home
    await writeSync(term, "After clear");
    const html = serializeAsHTML(term);
    expect(html).toContain("After clear");
    // "First line" should be in scrollback but not current screen
    disposeTerminal(term);
  });

  test("handles cursor position command", async () => {
    const term = createTerminal(80, 24);
    await writeSync(term, "\x1b[5;10H"); // Move cursor to row 5, col 10
    await writeSync(term, "Positioned");
    const html = serializeAsHTML(term);
    expect(html).toContain("Positioned");
    // CSI H should not leak through as literal characters
    expect(html).not.toMatch(/^[HJ]$/m);
    disposeTerminal(term);
  });

  test("handles resize", () => {
    const term = createTerminal(80, 24);
    term.terminal.resize(120, 40);
    expect(term.terminal.cols).toBe(120);
    expect(term.terminal.rows).toBe(40);
    disposeTerminal(term);
  });

  test("serialize returns valid HTML structure", async () => {
    const term = createTerminal(80, 24);
    await writeSync(term, "Test content");
    const html = serializeAsHTML(term);
    // Should be valid HTML (has span structure from xterm serialize addon)
    expect(html).toMatch(/<span|<div|Test content/);
    disposeTerminal(term);
  });
});