using System;
using System.Runtime.InteropServices;

namespace FastReport.Fonts
{
    /// <summary>
    /// OS/2 and Windows Metrics table 
    /// </summary>
    public class OS2WindowsMetricsClass : TrueTypeTable
    {
        #region "Type definition"

        /// <summary>
        /// Description of FontTextMetric structure
        /// </summary>
        [StructLayout(LayoutKind.Sequential)]
        public struct FontTextMetric
        {
            public int tmHeight;
            public int tmAscent;
            public int tmDescent;
            public int tmInternalLeading;
            public int tmExternalLeading;
            public int tmAveCharWidth;
            public int tmMaxCharWidth;
            public int tmWeight;
            public int tmOverhang;
            public int tmDigitizedAspectX;
            public int tmDigitizedAspectY;
            public char tmFirstChar;
            public char tmLastChar;
            public char tmDefaultChar;
            public char tmBreakChar;
            public byte tmItalic;
            public byte tmUnderlined;
            public byte tmStruckOut;
            public byte tmPitchAndFamily;
            public byte tmCharSet;
        }

        /// <summary>
        /// Description of FontPanose structure
        /// </summary>
        [StructLayout(LayoutKind.Sequential, Pack = 1)]
        public struct FontPanose
        {
            public byte bFamilyType;
            public byte bSerifStyle;
            public byte bWeight;
            public byte bProportion;
            public byte bContrast;
            public byte bStrokeVariation;
            public byte ArmStyle;
            public byte bLetterform;
            public byte bMidline;
            public byte bXHeight;
        }


        [StructLayout(LayoutKind.Sequential, Pack = 1)]
        public struct OS2WindowsMetrics
        {
            public ushort Version; // version number 0x0004
            public short xAvgCharWidth;
            public ushort usWeightClass;
            public ushort usWidthClass;
            public ushort fsType;
            public short ySubscriptXSize;
            public short ySubscriptYSize;
            public short ySubscriptXOffset;
            public short ySubscriptYOffset;
            public short ySuperscriptXSize;
            public short ySuperscriptYSize;
            public short ySuperscriptXOffset;
            public short ySuperscriptYOffset;
            public short yStrikeoutSize;
            public short yStrikeoutPosition;
            public short sFamilyClass;
#if false
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 10)]
            public byte[] panose; // = new byte[10];
#else
            public FontPanose panose;
#endif
            public uint ulUnicodeRange1;
            public uint ulUnicodeRange2;
            public uint ulUnicodeRange3;
            public uint ulUnicodeRange4;
#if true
            public byte achVendID1;
            public byte achVendID2;
            public byte achVendID3;
            public byte achVendID4;
#else
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 4)]
            public byte[] achVendID; //  = new vyte[4];
#endif
            public ushort fsSelection;
            public ushort usFirstCharIndex;
            public ushort usLastCharIndex;
            public short sTypoAscender;
            public short sTypoDescender;
            public short sTypoLineGap;
            public ushort usWinAscent;
            public ushort usWinDescent;
            public uint ulCodePageRange1;
            public uint ulCodePageRange2;
            public short sxHeight;
            public short sCapHeight;
            public ushort usDefaultChar;
            public ushort usBreakChar;
            public ushort usMaxContext;
        }
        #endregion

        internal OS2WindowsMetrics win_metrix;

        internal override void Load(FontStream stream)
        {
            stream.Position = this.Offset;
            win_metrix.Version = stream.ReadUInt16(); // version number 0x0004
                                                      //public short 
            win_metrix.xAvgCharWidth = stream.ReadInt16();
            win_metrix.usWeightClass = stream.ReadUInt16();
            win_metrix.usWidthClass = stream.ReadUInt16();
            win_metrix.fsType = stream.ReadUInt16();
            win_metrix.ySubscriptXSize = stream.ReadInt16();
            win_metrix.ySubscriptYSize = stream.ReadInt16();
            win_metrix.ySubscriptXOffset = stream.ReadInt16();
            win_metrix.ySubscriptYOffset = stream.ReadInt16();
            win_metrix.ySuperscriptXSize = stream.ReadInt16();
            win_metrix.ySuperscriptYSize = stream.ReadInt16();
            win_metrix.ySuperscriptXOffset = stream.ReadInt16();
            win_metrix.ySuperscriptYOffset = stream.ReadInt16();
            win_metrix.yStrikeoutSize = stream.ReadInt16();
            win_metrix.yStrikeoutPosition = stream.ReadInt16();
            win_metrix.sFamilyClass = stream.ReadInt16();

            //FontPanose 
            win_metrix.panose.bFamilyType = stream.ReadByte();
            win_metrix.panose.bSerifStyle = stream.ReadByte();
            win_metrix.panose.bWeight = stream.ReadByte();
            win_metrix.panose.bProportion = stream.ReadByte();
            win_metrix.panose.bContrast = stream.ReadByte();
            win_metrix.panose.bStrokeVariation = stream.ReadByte();
            win_metrix.panose.ArmStyle = stream.ReadByte();
            win_metrix.panose.bLetterform = stream.ReadByte();
            win_metrix.panose.bMidline = stream.ReadByte();
            win_metrix.panose.bXHeight = stream.ReadByte();

            win_metrix.ulUnicodeRange1 = stream.ReadUInt32();
            win_metrix.ulUnicodeRange2 = stream.ReadUInt32();
            win_metrix.ulUnicodeRange3 = stream.ReadUInt32();
            win_metrix.ulUnicodeRange4 = stream.ReadUInt32();

            win_metrix.achVendID1 = stream.ReadByte();
            win_metrix.achVendID2 = stream.ReadByte();
            win_metrix.achVendID3 = stream.ReadByte();
            win_metrix.achVendID4 = stream.ReadByte();

            win_metrix.fsSelection = stream.ReadUInt16();
            win_metrix.usFirstCharIndex = stream.ReadUInt16();
            win_metrix.usLastCharIndex = stream.ReadUInt16();
            win_metrix.sTypoAscender = stream.ReadInt16();
            win_metrix.sTypoDescender = stream.ReadInt16();
            win_metrix.sTypoLineGap = stream.ReadInt16();
            win_metrix.usWinAscent = stream.ReadUInt16();
            win_metrix.usWinDescent = stream.ReadUInt16();
            win_metrix.ulCodePageRange1 = stream.ReadUInt32();
            win_metrix.ulCodePageRange2 = stream.ReadUInt32();
            win_metrix.sxHeight = stream.ReadInt16();
            win_metrix.sCapHeight = stream.ReadInt16();
            win_metrix.usDefaultChar = stream.ReadUInt16();
            win_metrix.usBreakChar = stream.ReadUInt16();
            win_metrix.usMaxContext = stream.ReadUInt16();
        }

        internal override uint Save(FontStream source_not_used, FontStream stream, uint offset)
        {
            stream.Position = offset;
            stream.WriteUInt16(win_metrix.Version); // version number 0x0004
            stream.WriteInt16(win_metrix.xAvgCharWidth);
            stream.WriteUInt16(win_metrix.usWeightClass);
            stream.WriteUInt16(win_metrix.usWidthClass);
            stream.WriteUInt16(win_metrix.fsType);
            stream.WriteInt16(win_metrix.ySubscriptXSize);
            stream.WriteInt16(win_metrix.ySubscriptYSize);
            stream.WriteInt16(win_metrix.ySubscriptXOffset);
            stream.WriteInt16(win_metrix.ySubscriptYOffset);
            stream.WriteInt16(win_metrix.ySuperscriptXSize);
            stream.WriteInt16(win_metrix.ySuperscriptYSize);
            stream.WriteInt16(win_metrix.ySuperscriptXOffset);
            stream.WriteInt16(win_metrix.ySuperscriptYOffset);
            stream.WriteInt16(win_metrix.yStrikeoutSize);
            stream.WriteInt16(win_metrix.yStrikeoutPosition);
            stream.WriteInt16(win_metrix.sFamilyClass);

            stream.WriteByte(win_metrix.panose.bFamilyType);
            stream.WriteByte(win_metrix.panose.bSerifStyle);
            stream.WriteByte(win_metrix.panose.bWeight);
            stream.WriteByte(win_metrix.panose.bProportion);
            stream.WriteByte(win_metrix.panose.bContrast);
            stream.WriteByte(win_metrix.panose.bStrokeVariation);
            stream.WriteByte(win_metrix.panose.ArmStyle);
            stream.WriteByte(win_metrix.panose.bLetterform);
            stream.WriteByte(win_metrix.panose.bMidline);
            stream.WriteByte(win_metrix.panose.bXHeight);

            stream.WriteUInt32(win_metrix.ulUnicodeRange1);
            stream.WriteUInt32(win_metrix.ulUnicodeRange2);
            stream.WriteUInt32(win_metrix.ulUnicodeRange3);
            stream.WriteUInt32(win_metrix.ulUnicodeRange4);
#if true
            stream.WriteByte(win_metrix.achVendID1);
            stream.WriteByte(win_metrix.achVendID2);
            stream.WriteByte(win_metrix.achVendID3);
            stream.WriteByte(win_metrix.achVendID4);
#else
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 4)]
            public byte[] achVendID; //  = new vyte[4];
#endif
            stream.WriteUInt16(win_metrix.fsSelection);
            stream.WriteUInt16(win_metrix.usFirstCharIndex);
            stream.WriteUInt16(win_metrix.usLastCharIndex);
            stream.WriteInt16(win_metrix.sTypoAscender);
            stream.WriteInt16(win_metrix.sTypoDescender);
            stream.WriteInt16(win_metrix.sTypoLineGap);
            stream.WriteUInt16(win_metrix.usWinAscent);
            stream.WriteUInt16(win_metrix.usWinDescent);
            stream.WriteUInt32(win_metrix.ulCodePageRange1);
            stream.WriteUInt32(win_metrix.ulCodePageRange2);
            stream.WriteInt16(win_metrix.sxHeight);
            stream.WriteInt16(win_metrix.sCapHeight);
            stream.WriteUInt16(win_metrix.usDefaultChar);
            stream.WriteUInt16(win_metrix.usBreakChar);
            stream.WriteUInt16(win_metrix.usMaxContext);

            offset = (offset + this.Length + 3) & 0xfffffffc;
            return offset;
        }

        // Public properties
#pragma warning disable CS3001, CS3002, CS3003, CS1591

        public bool IsBold
        {
            get
            {
                //                return win_metrix.usWeightClass >= 700;
                return (win_metrix.fsSelection & 0x20) != 0;
            }
        }
        public ushort Ascent { get { return win_metrix.usWinAscent; } }
        public ushort Descent { get { return win_metrix.usWinDescent; } }
        public short LineGap { get { return win_metrix.sTypoLineGap; } }
        public short AvgCharWidth { get { return win_metrix.xAvgCharWidth; } }
        public ushort Weight { get { return win_metrix.usWeightClass; } }
        public ushort WidthClass { get { return win_metrix.usWidthClass; } }
        public short Height { get { return win_metrix.sxHeight; } }
        public ushort BreakChar { get { return win_metrix.usBreakChar; } }
        public ushort DefaultChar { get { return win_metrix.usDefaultChar; } }
        public ushort FirstCharIndex { get { return win_metrix.usFirstCharIndex; } }
        public ushort LastCharIndex { get { return win_metrix.usLastCharIndex; } }
        public ushort LicensingRights { get { return win_metrix.fsType; } }
        public OS2WindowsMetricsClass.FontPanose Panose { get { return win_metrix.panose; } }
        public OS2WindowsMetricsClass(TrueTypeTable src) : base(src) { }
        public uint UnicodeRange1 { get { return win_metrix.ulUnicodeRange1; } }
        public uint UnicodeRange2 { get { return win_metrix.ulUnicodeRange2; } }
        public uint UnicodeRange3 { get { return win_metrix.ulUnicodeRange3; } }
        public uint UnicodeRange4 { get { return win_metrix.ulUnicodeRange4; } }
        public short FamilyClass { get { return win_metrix.sFamilyClass; } }
        public ushort Selection { get { return win_metrix.fsSelection; } }
        public uint CodepageRange1 { get { return win_metrix.ulCodePageRange1; } }
        public uint CodepageRange2 { get { return win_metrix.ulCodePageRange2; } }
        public string VendorID
        {
            get
            {
                return "" +
                  (char)win_metrix.achVendID1 +
                  (char)win_metrix.achVendID2 +
                  (char)win_metrix.achVendID3 +
                  (char)win_metrix.achVendID4;
            }
        }
#pragma warning restore
    }

}