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

using System.IO;

namespace SixLabors.Fonts.Tables.AdvancedTypographic.GPos {
  /// <summary>
  /// Represents the Mark2Array table used in MarkToMark attachment positioning (GPOS LookupType 6).
  /// The Mark2Array table contains an array of Mark2Records, one for each mark2 glyph (the base mark), ordered by the mark2 Coverage index.
  /// <see href="https://learn.microsoft.com/en-us/typography/opentype/spec/gpos#mark-to-mark-attachment-positioning-format-1-mark-to-mark-attachment"/>
  /// </summary>
  internal class Mark2ArrayTable
  {
      /// <summary>
      /// Initializes a new instance of the <see cref="Mark2ArrayTable"/> class.
      /// </summary>
      /// <param name="reader">The big endian binary reader.</param>
      /// <param name="markClassCount">The number of mark classes.</param>
      /// <param name="offset">The offset to the start of the mark array table.</param>
      public Mark2ArrayTable(BigEndianBinaryReader reader, ushort markClassCount, long offset)
      {
          // +--------------+------------------------+--------------------------------------------------------------------------------------+
          // | Type         | Name                   | Description                                                                          |
          // +==============+========================+======================================================================================+
          // | uint16       | mark2Count             | Number of Mark2Records.                                                              |
          // +--------------+------------------------+--------------------------------------------------------------------------------------+
          // | Mark2Record  | mark2Records[markCount]| Array of Mark2Records, in Coverage order.                                            |
          // +--------------+------------------------+--------------------------------------------------------------------------------------+
          reader.Seek(offset, SeekOrigin.Begin);
          ushort markCount = reader.ReadUInt16();
          this.Mark2Records = new Mark2Record[markCount];
          for (int i = 0; i < markCount; i++)
          {
              this.Mark2Records[i] = new Mark2Record(reader, markClassCount, offset);
          }
      }

      /// <summary>
      /// Gets the array of Mark2 records, in Coverage order.
      /// </summary>
      public Mark2Record[] Mark2Records { get; }
  }
}