namespace Cosmos.System.FileSystem.FAT.Listing
{
    /// <summary>
    /// Fat directory entry metadata class.
    /// </summary>
    public sealed class FatDirectoryEntryMetadata
    {
        /// <summary>
        /// Entry data offset.
        /// </summary>
        public readonly uint DataOffset;
        /// <summary>
        /// Entry data length.
        /// </summary>
        public readonly uint DataLength;

        private FatDirectoryEntryMetadata(uint aDataOffset, uint aDataLength)
        {
            DataOffset = aDataOffset;
            DataLength = aDataLength;
        }

        /// <summary>
        /// Directory entry first byte matadata. This is filename first byte.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata FirstByte = new FatDirectoryEntryMetadata(0x00, 1);
        /// <summary>
        /// Directory entry short name matadata. This is the filename + filename extension. 
        /// The dot '.' separate filename and filename extention is implied.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata ShortName = new FatDirectoryEntryMetadata(0x00, 11);
        /// <summary>
        /// Directory entry attributes matadata. This contains information about the directory.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata Attributes = new FatDirectoryEntryMetadata(0x0B, 1);
        /// <summary>
        /// Directory entry reserved matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata NTReserved = new FatDirectoryEntryMetadata(0x0C, 1);
        /// <summary>
        /// Directory entry creation time tenths of a second matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata CreationTimeTenthsOfASecond = new FatDirectoryEntryMetadata(0x0D, 1);
        /// <summary>
        /// Directory entry creation time matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata CreationTime = new FatDirectoryEntryMetadata(0x0E, 2);
        /// <summary>
        /// Directory entry creation date matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata CreationDate = new FatDirectoryEntryMetadata(0x10, 2);
        /// <summary>
        /// Directory entry last accessed date matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata AccessedDate = new FatDirectoryEntryMetadata(0x12, 2);
        /// <summary>
        /// Directory entry first cluster high matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata FirstClusterHigh = new FatDirectoryEntryMetadata(0x14, 2);
        /// <summary>
        /// Directory entry last modified time matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata ModifiedTime = new FatDirectoryEntryMetadata(0x16, 2);
        /// <summary>
        /// Directory entry last modified date matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata ModifiedDate = new FatDirectoryEntryMetadata(0x18, 2);
        /// <summary>
        /// Directory entry first cluster low matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata FirstClusterLow = new FatDirectoryEntryMetadata(0x1A, 2);
        /// <summary>
        /// Directory entry drectory size matadata.
        /// </summary>
        public static readonly FatDirectoryEntryMetadata Size = new FatDirectoryEntryMetadata(0x1C, 4);

        /// <summary>
        /// Long filename entry metadata class. This class can not be inherited.
        /// </summary>
        public sealed class LongFilenameEntryMetadata
        {
            /// <summary>
            /// Directory entry sequence number and allocation status matadata.
            /// </summary>
            public static readonly FatDirectoryEntryMetadata SequenceNumberAndAllocationStatus = new FatDirectoryEntryMetadata(0x00, 1);
            /// <summary>
            /// Directory entry LongName1 matadata.
            /// </summary>
            public static readonly FatDirectoryEntryMetadata LongName1 = new FatDirectoryEntryMetadata(0x01, 10);
            /// <summary>
            /// Directory entry attributes matadata.
            /// </summary>
            public static readonly FatDirectoryEntryMetadata Attributes = new FatDirectoryEntryMetadata(0x0B, 1);
            //public static readonly FatDirectoryEntryMetadata Reserved1 = new FatDirectoryEntryMetadata(0x0C, 1);
            /// <summary>
            /// Directory entry checksum matadata.
            /// </summary>
            public static readonly FatDirectoryEntryMetadata Checksum = new FatDirectoryEntryMetadata(0x0D, 1);
            /// <summary>
            /// Directory entry LongName2 matadata.
            /// </summary>
            public static readonly FatDirectoryEntryMetadata LongName2 = new FatDirectoryEntryMetadata(0x0E, 12);
            //public static readonly FatDirectoryEntryMetadata Reserved2 = new FatDirectoryEntryMetadata(0x1A, 2);
            /// <summary>
            /// Directory entry LongName3 matadata.
            /// </summary>
            public static readonly FatDirectoryEntryMetadata LongName3 = new FatDirectoryEntryMetadata(0x1C, 4);
        }
    }
}