using System;
using System.IO;
using ICSharpCode.SharpZipLib.Checksums;
using ICSharpCode.SharpZipLib.Zip.Compression;
using ICSharpCode.SharpZipLib.Zip.Compression.Streams;

namespace ICSharpCode.SharpZipLib.GZip
{
	// Token: 0x0200002C RID: 44
	public class GZipOutputStream : DeflaterOutputStream
	{
		// Token: 0x0600014E RID: 334 RVA: 0x00008F57 File Offset: 0x00007F57
		public GZipOutputStream(Stream baseOutputStream)
			: this(baseOutputStream, 4096)
		{
		}

		// Token: 0x0600014F RID: 335 RVA: 0x00008F65 File Offset: 0x00007F65
		public GZipOutputStream(Stream baseOutputStream, int size)
			: base(baseOutputStream, new Deflater(-1, true), size)
		{
		}

		// Token: 0x06000150 RID: 336 RVA: 0x00008F81 File Offset: 0x00007F81
		public void SetLevel(int level)
		{
			if (level < 1)
			{
				throw new ArgumentOutOfRangeException("level");
			}
			this.deflater_.SetLevel(level);
		}

		// Token: 0x06000151 RID: 337 RVA: 0x00008F9E File Offset: 0x00007F9E
		public int GetLevel()
		{
			return this.deflater_.GetLevel();
		}

		// Token: 0x06000152 RID: 338 RVA: 0x00008FAB File Offset: 0x00007FAB
		public override void Write(byte[] buffer, int offset, int count)
		{
			if (this.state_ == GZipOutputStream.OutputState.Header)
			{
				this.WriteHeader();
			}
			if (this.state_ != GZipOutputStream.OutputState.Footer)
			{
				throw new InvalidOperationException("Write not permitted in current state");
			}
			this.crc.Update(buffer, offset, count);
			base.Write(buffer, offset, count);
		}

		// Token: 0x06000153 RID: 339 RVA: 0x00008FE8 File Offset: 0x00007FE8
		public override void Close()
		{
			try
			{
				this.Finish();
			}
			finally
			{
				if (this.state_ != GZipOutputStream.OutputState.Closed)
				{
					this.state_ = GZipOutputStream.OutputState.Closed;
					if (base.IsStreamOwner)
					{
						this.baseOutputStream_.Close();
					}
				}
			}
		}

		// Token: 0x06000154 RID: 340 RVA: 0x00009034 File Offset: 0x00008034
		public override void Finish()
		{
			if (this.state_ == GZipOutputStream.OutputState.Header)
			{
				this.WriteHeader();
			}
			if (this.state_ == GZipOutputStream.OutputState.Footer)
			{
				this.state_ = GZipOutputStream.OutputState.Finished;
				base.Finish();
				uint num = (uint)(this.deflater_.TotalIn & (long)((ulong)(-1)));
				uint num2 = (uint)(this.crc.Value & (long)((ulong)(-1)));
				byte[] array = new byte[]
				{
					(byte)num2,
					(byte)(num2 >> 8),
					(byte)(num2 >> 16),
					(byte)(num2 >> 24),
					(byte)num,
					(byte)(num >> 8),
					(byte)(num >> 16),
					(byte)(num >> 24)
				};
				this.baseOutputStream_.Write(array, 0, array.Length);
			}
		}

		// Token: 0x06000155 RID: 341 RVA: 0x000090E4 File Offset: 0x000080E4
		private void WriteHeader()
		{
			if (this.state_ == GZipOutputStream.OutputState.Header)
			{
				this.state_ = GZipOutputStream.OutputState.Footer;
				int num = (int)((DateTime.Now.Ticks - new DateTime(1970, 1, 1).Ticks) / 10000000L);
				byte[] array = new byte[] { 31, 139, 8, 0, 0, 0, 0, 0, 0, byte.MaxValue };
				array[4] = (byte)num;
				array[5] = (byte)(num >> 8);
				array[6] = (byte)(num >> 16);
				array[7] = (byte)(num >> 24);
				byte[] array2 = array;
				this.baseOutputStream_.Write(array2, 0, array2.Length);
			}
		}

		// Token: 0x040000B6 RID: 182
		protected Crc32 crc = new Crc32();

		// Token: 0x040000B7 RID: 183
		private GZipOutputStream.OutputState state_;

		// Token: 0x0200002D RID: 45
		private enum OutputState
		{
			// Token: 0x040000B9 RID: 185
			Header,
			// Token: 0x040000BA RID: 186
			Footer,
			// Token: 0x040000BB RID: 187
			Finished,
			// Token: 0x040000BC RID: 188
			Closed
		}
	}
}