// Copyright (c) Six Labors.
// Licensed under the Six Labors Split License.

using System;

namespace SixLabors.Fonts.Tables.AdvancedTypographic {
  /// <summary>
  /// LookupFlag bit enumeration, see: https://docs.microsoft.com/en-us/typography/opentype/spec/chapter2#lookup-table
  /// </summary>
  [Flags]
  internal enum LookupFlags : ushort
  {
      /// <summary>
      /// This bit relates only to the correct processing of the cursive attachment lookup type (GPOS lookup type 3).
      /// When this bit is set, the last glyph in a given sequence to which the cursive attachment lookup is applied, will be positioned on the baseline.
      /// </summary>
      RightToLeft = 0x0001,

      /// <summary>
      /// If set, skips over base glyphs.
      /// </summary>
      IgnoreBaseGlyphs = 0x0002,

      /// <summary>
      /// If set, skips over ligatures.
      /// </summary>
      IgnoreLigatures = 0x0004,

      /// <summary>
      /// If set, skips over all combining marks.
      /// </summary>
      IgnoreMarks = 0x0008,

      /// <summary>
      /// If set, indicates that the lookup table structure is followed by a MarkFilteringSet field.
      /// The layout engine skips over all mark glyphs not in the mark filtering set indicated.
      /// </summary>
      UseMarkFilteringSet = 0x0010,

      /// <summary>
      /// For future use (Set to zero).
      /// </summary>
      Reserved = 0x00E0,

      /// <summary>
      /// If not zero, skips over all marks of attachment type different from specified.
      /// </summary>
      MarkAttachmentTypeMask = 0xFF00
  }
}