/**
 * Copyright (c) 2026 The xterm.js authors. All rights reserved.
 * @license MIT
 */
import { Attributes, BgFlags, FgFlags, UnderlineStyle } from 'common/buffer/Constants';
import { CellData } from 'common/buffer/CellData';
import { assert } from 'chai';

function createStyledCell(char: string, underlineStyle: UnderlineStyle, underlineColor: number): CellData {
  const cell = new CellData();
  const fg = Attributes.CM_P256 | 12 | FgFlags.BOLD | FgFlags.UNDERLINE;
  cell.setFromCharData([fg, char, 1, char.charCodeAt(0)]);
  cell.bg = Attributes.CM_P16 | 2 | BgFlags.ITALIC;
  cell.extended.underlineStyle = underlineStyle;
  cell.extended.underlineColor = Attributes.CM_P256 | underlineColor;
  cell.updateExtended();
  return cell;
}

describe('CellData', () => {
  describe('attributesEquals', () => {
    it('returns true for same attributes with different chars', () => {
      const cellA = createStyledCell('A', UnderlineStyle.DOUBLE, 45);
      const cellB = createStyledCell('B', UnderlineStyle.DOUBLE, 45);

      assert.equal(cellA.attributesEquals(cellB), true);
    });

    it('detects underline style changes', () => {
      const cellA = createStyledCell('A', UnderlineStyle.DOUBLE, 45);
      const cellB = createStyledCell('B', UnderlineStyle.SINGLE, 45);

      assert.equal(cellA.attributesEquals(cellB), false);
    });

    it('detects underline color changes', () => {
      const cellA = createStyledCell('A', UnderlineStyle.SINGLE, 45);
      const cellB = createStyledCell('B', UnderlineStyle.SINGLE, 46);

      assert.equal(cellA.attributesEquals(cellB), false);
    });

    it('ignores underline variant offsets', () => {
      const cellA = createStyledCell('A', UnderlineStyle.SINGLE, 45);
      const cellB = createStyledCell('B', UnderlineStyle.SINGLE, 45);
      cellA.extended.underlineVariantOffset = 1;
      cellB.extended.underlineVariantOffset = 3;
      cellA.updateExtended();
      cellB.updateExtended();

      assert.equal(cellA.attributesEquals(cellB), true);
    });

    it('ignores url ids', () => {
      const cellA = createStyledCell('A', UnderlineStyle.SINGLE, 45);
      const cellB = createStyledCell('B', UnderlineStyle.SINGLE, 45);
      cellA.extended.urlId = 1;
      cellB.extended.urlId = 2;
      cellA.updateExtended();
      cellB.updateExtended();

      assert.equal(cellA.attributesEquals(cellB), true);
    });
  });
});