using System;
using System.Collections;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Text;

#pragma warning disable CS3001, CS3002, CS3003, CS1591

namespace FastReport.Fonts
{
    /// <summary>
    /// Name table keep human friendly description about font properties, including font names, author and copyright notes
    /// </summary>
    public class NameTableClass : TrueTypeTable, ICollection
    {
        #region "Structure dfinition"
        public enum NameID
        {
            CopyrightNotice = 0,
            FamilyName = 1,
            SubFamilyName = 2,
            UniqueID = 3,
            FullName = 4,
            Version = 5,
            PostscriptName = 6,
            Trademark = 7,
            Manufacturer = 8,
            Designer = 9,
            Description = 10,
            URL_Vendor = 11,
            URL_Designer = 12,
            LicenseDescription = 13,
            LicenseInfoURL = 14,
            PreferredFamily = 16,
            PreferredSubFamily = 17,
            CompatibleFull = 18,
            SampleText = 19,
            PostscriptCID = 20,
            WWS_Family_Name = 21,
            WWS_SubFamily_Name = 22
        }


        [StructLayout(LayoutKind.Explicit, Pack = 1)]
        public struct NamingTableHeader
        {
            [FieldOffset(0)]
            public ushort TableVersion;
            [FieldOffset(2)]
            public ushort Count;
            [FieldOffset(4)]
            public ushort stringOffset;
        }

        [StructLayout(LayoutKind.Explicit, Pack = 1)]
        public struct NamingRecord
        {
            [FieldOffset(0)]
            public ushort PlatformID;
            [FieldOffset(2)]
            public ushort EncodingID;
            [FieldOffset(4)]
            public ushort LanguageID;
            [FieldOffset(6)]
            public ushort NameID;
            [FieldOffset(8)]
            public ushort Length;
            [FieldOffset(10)]
            public ushort Offset;
        }

        public readonly struct LangTagReccord
        {
            public readonly ushort lenght;
            public readonly ushort offset;
            public LangTagReccord(ushort lenght, ushort offset)
            {
                this.lenght = lenght;
                this.offset = offset;
            }
        };
        #endregion

        NamingTableHeader name_header;
        int langTagCount = 0;
        NamingRecord[] name_rec;
        LangTagReccord[] tags;

        Dictionary<NameID, List<string>> names = new Dictionary<NameID, List<string>>();

        public Dictionary<NameID, List<string>> NamesDict
        {
            get
            {
                return names;
            }
        }

        public int Count
        {
            get
            {
                return name_header.Count;
            }
        }

        public object SyncRoot
        {
            get
            {
                return null; // Names.SyncRoot;
            }
        }

        public bool IsSynchronized
        {
            get
            {
                return true; // Names.IsSynchronized;
            }
        }

        private void ChangeEndian()
        {
            name_header.TableVersion = SwapUInt16(name_header.TableVersion);
            name_header.Count = SwapUInt16(name_header.Count);
            name_header.stringOffset = SwapUInt16(name_header.stringOffset);
        }

        internal override void Load(FontStream stream)
        {
            stream.Position = this.Offset;
            name_header.TableVersion = stream.ReadUInt16();
            name_header.Count = stream.ReadUInt16();
            name_header.stringOffset = stream.ReadUInt16();
            name_rec = new NamingRecord[name_header.Count];

            for (int i = 0; i < name_header.Count; i++)
            {
                name_rec[i].PlatformID = stream.ReadUInt16();
                name_rec[i].EncodingID = stream.ReadUInt16();
                name_rec[i].LanguageID = stream.ReadUInt16();
                name_rec[i].NameID = stream.ReadUInt16();
                name_rec[i].Length = stream.ReadUInt16();
                name_rec[i].Offset = stream.ReadUInt16();
            }

            if (name_header.TableVersion == 1)
            {
                this.langTagCount = stream.ReadUInt16();
                tags = new LangTagReccord[langTagCount];
                for (int i = 0; i < this.langTagCount; i++)
                {
                    tags[i] = new LangTagReccord(stream.ReadUInt16(), stream.ReadUInt16());
                }
            }

            // Tables ready. Let's look into them
            byte[] Temp;
            string value;
            int j;
            for (int i = 0; i < name_header.Count; i++)
            {
                if (name_rec[i].PlatformID == 1)
                {
                    Temp = new byte[name_rec[i].Length];

                    stream.Position = this.Offset + name_header.stringOffset + name_rec[i].Offset;
                    stream.Read(Temp, name_rec[i].Length);

                    value = Encoding.GetEncoding("utf-8").GetString(Temp);
                }
                else
                {
                    Temp = new byte[name_rec[i].Length];
                    stream.Position = this.Offset + name_header.stringOffset + name_rec[i].Offset;
                    stream.Read(Temp, name_rec[i].Length);

                    value = Encoding.GetEncoding(1201).GetString(Temp);
                }
                NameID id = (NameID)name_rec[i].NameID;
                List<string> values;
                if (!names.ContainsKey(id))
                {
                    values = new List<string>();
                    names.Add(id, values);
                }
                else
                {
                    values = (List<string>)names[id];
                }
                if (!values.Contains(value))
                {
                    values.Add(value);
                }
            }
        }

        public void CopyTo(Array array, int index)
        {
            throw new NotImplementedException();
        }

        public IEnumerator GetEnumerator()
        {
            return names.Keys.GetEnumerator();
        }

        public ICollection this[NameID Index]
        {
            get
            {
                ICollection rec = null;
                if (names.ContainsKey(Index))
                {
                    rec = names[Index] as ICollection;
                }
                return rec;
            }
        }

        public NameTableClass(TrueTypeTable src) : base(src) { }
    }

}
#pragma warning restore