//
// System.Drawing.Imaging.Metafile.cs
//
// Authors:
//	Christian Meyer, eMail: Christian.Meyer@cs.tum.edu
//	Dennis Hayes (dennish@raytek.com)
//	Sebastien Pouliot  <sebastien@ximian.com>
//
// (C) 2002 Ximian, Inc.  http://www.ximian.com
// Copyright (C) 2004,2006-2007 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//

using System.IO;
using System.Reflection;
using System.ComponentModel;
using System.Runtime.InteropServices;

namespace System.Drawing.Imaging {

	[MonoTODO ("Metafiles, both WMF and EMF formats, are only partially supported.")]
	[Serializable]
	[Editor ("System.Drawing.Design.MetafileEditor, " + Consts.AssemblySystem_Drawing_Design, typeof (System.Drawing.Design.UITypeEditor))]
	public sealed class Metafile : Image {

		// Non-null if a graphics instance was created using
		// Graphics.FromImage(this) The metadata holder is responsible for
		// freeing the nativeImage if the Metadata instance is disposed before
		// the Graphics instance.
		private MetafileHolder _metafileHolder;

		// A class responsible for disposing of the native Metafile instance
		// if it needs to outlive the managed Metafile instance.
		//
		// The following are both legal with win32 GDI+:
		//     Metafile mf = ...; // get a metafile instance
		//     Graphics g = Graphics.FromImage(mf); // get a graphics instance
		//     g.Dispose();  mf.Dispose(); // dispose of the graphics instance first
		//   OR
		//     mf.Dispose(); g.Dispose();  // dispose of the metafile instance first
		//
		// ligbgdiplus has a bug where disposing of the metafile instance first will
		// trigger a use of freed memory when the graphics instance is disposed, which
		// could lead to crashes when the native memory is reused.
		//
		// The metafile holder is designed to take ownership of the native metafile image
		// when the managed Metafile instance is disposed while a Graphics instance is still
		// not disposed (ie the second code pattern above) and to keep the native image alive until the graphics
		// instance is disposed.
		//
		// Note that the following throws, so we only ever need to keep track of one Graphics
		// instance at a time:
		//	Metafile mf = ...;  // get a metafile instance
		//	Graphics g = Graphics.FromImage(mf);
		//	Graphics g2 = Graphics.FromImage(mf);  // throws OutOfMemoryException on GDI+ on Win32
		internal sealed class MetafileHolder : IDisposable
		{
			private bool _disposed;
			private IntPtr _nativeImage;


			internal bool Disposed { get => _disposed; }
			internal MetafileHolder()
			{
				_disposed = false;
				_nativeImage = IntPtr.Zero;
			}

			~MetafileHolder() => Dispose(false);

			public void Dispose()
			{
				Dispose(true);
				GC.SuppressFinalize(this);
			}

			internal void Dispose(bool disposing)
			{
				if (!_disposed)
				{
					IntPtr nativeImage = _nativeImage;
					_nativeImage = IntPtr.Zero;
					_disposed = true;
					if (nativeImage != IntPtr.Zero)
					{
						Status status = GDIPlus.GdipDisposeImage(nativeImage);
						GDIPlus.CheckStatus(status);
					}
				}
			}

			internal void MetafileDisposed(IntPtr nativeImage)
			{
				_nativeImage = nativeImage;
			}

			internal void GraphicsDisposed()
			{
				Dispose();
			}
		}

		internal MetafileHolder AddMetafileHolder()
		{
			// If _metafileHolder is not null and hasn't been disposed yet, there's already a graphics instance associated with
			// this metafile, the native code will return an error status.
			if (_metafileHolder != null && !_metafileHolder.Disposed)
				return null;
			_metafileHolder = new MetafileHolder();
			return _metafileHolder;
		}

		// constructors

		internal Metafile (IntPtr ptr)
		{
			nativeObject = ptr;
		}

		// Usually called when cloning images that need to have
		// not only the handle saved, but also the underlying stream
		// (when using MS GDI+ and IStream we must ensure the stream stays alive for all the life of the Image)
		internal Metafile (IntPtr ptr, Stream stream)
		{
			// under Win32 stream is owned by SD/GDI+ code
			if (GDIPlus.RunningOnWindows ())
				this.stream = stream;
			nativeObject = ptr;
		}

		public Metafile (Stream stream) 
		{
			if (stream == null)
				throw new ArgumentException ("stream");

			Status status;
			if (GDIPlus.RunningOnUnix ()) {
				// With libgdiplus we use a custom API for this, because there's no easy way
				// to get the Stream down to libgdiplus. So, we wrap the stream with a set of delegates.
				GDIPlus.GdiPlusStreamHelper sh = new GDIPlus.GdiPlusStreamHelper (stream, false);
				status = GDIPlus.GdipCreateMetafileFromDelegate_linux (sh.GetHeaderDelegate, sh.GetBytesDelegate, 
					sh.PutBytesDelegate, sh.SeekDelegate, sh.CloseDelegate, sh.SizeDelegate, out nativeObject);
			} else {
				status = GDIPlus.GdipCreateMetafileFromStream (new ComIStreamWrapper (stream), out nativeObject);
			}
			GDIPlus.CheckStatus (status);
		}

		public Metafile (string filename) 
		{
			if (filename == null)
				throw new ArgumentNullException ("filename");
			if (filename.Length == 0)
				throw new ArgumentException ("filename");

			Status status = GDIPlus.GdipCreateMetafileFromFile (filename, out nativeObject);
			if (status == Status.GenericError)
				throw new ExternalException ("Couldn't load specified file.");
			GDIPlus.CheckStatus (status);
		}

		public Metafile (IntPtr henhmetafile, bool deleteEmf) 
		{
			Status status = GDIPlus.GdipCreateMetafileFromEmf (henhmetafile, deleteEmf, out nativeObject);
			GDIPlus.CheckStatus (status);
		}

		public Metafile (IntPtr referenceHdc, EmfType emfType) :
			this (referenceHdc, new RectangleF (), MetafileFrameUnit.GdiCompatible, emfType, null)
		{
		}

		public Metafile (IntPtr referenceHdc, Rectangle frameRect) :
			this (referenceHdc, frameRect, MetafileFrameUnit.GdiCompatible, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (IntPtr referenceHdc, RectangleF frameRect) :
			this (referenceHdc, frameRect, MetafileFrameUnit.GdiCompatible, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (IntPtr hmetafile, WmfPlaceableFileHeader wmfHeader) 
		{
			Status status = GDIPlus.GdipCreateMetafileFromEmf (hmetafile, false, out nativeObject);
			GDIPlus.CheckStatus (status);
		}

		public Metafile (Stream stream, IntPtr referenceHdc) :
			this (stream, referenceHdc, new RectangleF (), MetafileFrameUnit.GdiCompatible, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (string fileName, IntPtr referenceHdc) :
			this (fileName, referenceHdc, new RectangleF (), MetafileFrameUnit.GdiCompatible, EmfType.EmfPlusDual,
			null)
		{
		}

		public Metafile (IntPtr referenceHdc, EmfType emfType, string description) :
			this (referenceHdc, new RectangleF (), MetafileFrameUnit.GdiCompatible, emfType, description)
		{
		}

		public Metafile (IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit) :
			this (referenceHdc, frameRect, frameUnit, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit) :
			this (referenceHdc, frameRect, frameUnit, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (IntPtr hmetafile, WmfPlaceableFileHeader wmfHeader, bool deleteWmf) 
		{
			Status status = GDIPlus.GdipCreateMetafileFromEmf (hmetafile, deleteWmf, out nativeObject);
			GDIPlus.CheckStatus (status);
		}

		public Metafile (Stream stream, IntPtr referenceHdc, EmfType type) :
			this (stream, referenceHdc, new RectangleF (), MetafileFrameUnit.GdiCompatible, type, null)
		{
		}

		public Metafile (Stream stream, IntPtr referenceHdc, Rectangle frameRect) :
			this (stream, referenceHdc, frameRect, MetafileFrameUnit.GdiCompatible, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (Stream stream, IntPtr referenceHdc, RectangleF frameRect) :
			this (stream, referenceHdc, frameRect, MetafileFrameUnit.GdiCompatible, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (string fileName, IntPtr referenceHdc, EmfType type) :
			this (fileName, referenceHdc, new RectangleF (), MetafileFrameUnit.GdiCompatible, type, null)
		{
		}

		public Metafile (string fileName, IntPtr referenceHdc, Rectangle frameRect) :
			this (fileName, referenceHdc, frameRect, MetafileFrameUnit.GdiCompatible, EmfType.EmfPlusDual, null)
		{
		}
		
		public Metafile (string fileName, IntPtr referenceHdc, RectangleF frameRect) :
			this (fileName, referenceHdc, frameRect, MetafileFrameUnit.GdiCompatible, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit, EmfType type) :
			this (referenceHdc, frameRect, frameUnit, type, null)
		{
		}

		public Metafile (IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit, EmfType type) :
			this (referenceHdc, frameRect, frameUnit, type, null)
		{
		}

		public Metafile (Stream stream, IntPtr referenceHdc, EmfType type, string description) :
			this (stream, referenceHdc, new RectangleF (), MetafileFrameUnit.GdiCompatible, type, description)
		{
		}

		public Metafile (Stream stream, IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit) :
			this (stream, referenceHdc, frameRect, frameUnit, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (Stream stream, IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit) :
			this (stream, referenceHdc, frameRect, frameUnit, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (string fileName, IntPtr referenceHdc, EmfType type, string description) :
			this (fileName, referenceHdc, new RectangleF (), MetafileFrameUnit.GdiCompatible, type, description)
		{
		}

		public Metafile (string fileName, IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit) :
			this (fileName, referenceHdc, frameRect, frameUnit, EmfType.EmfPlusDual, null)
		{
		}
		
		public Metafile (string fileName, IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit) :
			this (fileName, referenceHdc, frameRect, frameUnit, EmfType.EmfPlusDual, null)
		{
		}

		public Metafile (IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit, EmfType type,
			string desc)
		{
			Status status = GDIPlus.GdipRecordMetafileI (referenceHdc, type, ref frameRect, frameUnit,
				desc, out nativeObject);
			GDIPlus.CheckStatus (status);
		}

		public Metafile (IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit, EmfType type,
			string description)
		{
			Status status = GDIPlus.GdipRecordMetafile (referenceHdc, type, ref frameRect, frameUnit,
				description, out nativeObject);
			GDIPlus.CheckStatus (status);
		}

		public Metafile (Stream stream, IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit,
			EmfType type) : this (stream, referenceHdc, frameRect, frameUnit, type, null)
		{
		}

		public Metafile (Stream stream, IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit,
			EmfType type) : this (stream, referenceHdc, frameRect, frameUnit, type, null)
		{
		}

		public Metafile (string fileName, IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit,
			EmfType type) : this (fileName, referenceHdc, frameRect, frameUnit, type, null)
		{
		}
		
		public Metafile (string fileName, IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit,
			string description) : this (fileName, referenceHdc, frameRect, frameUnit, EmfType.EmfPlusDual, description)
		{
		}

		public Metafile (string fileName, IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit,
			EmfType type) : this (fileName, referenceHdc, frameRect, frameUnit, type, null)
		{
		}
		
		public Metafile (string fileName, IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit, 
			string desc) : this (fileName, referenceHdc, frameRect, frameUnit, EmfType.EmfPlusDual,
			desc) 
		{
		}
		
		public Metafile (Stream stream, IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit, 
			EmfType type, string description) 
		{
			if (stream == null)
				throw new NullReferenceException ("stream");

			Status status = Status.NotImplemented;
			if (GDIPlus.RunningOnUnix ()) {
				// With libgdiplus we use a custom API for this, because there's no easy way
				// to get the Stream down to libgdiplus. So, we wrap the stream with a set of delegates.
				GDIPlus.GdiPlusStreamHelper sh = new GDIPlus.GdiPlusStreamHelper (stream, false);
				status = GDIPlus.GdipRecordMetafileFromDelegateI_linux (sh.GetHeaderDelegate, sh.GetBytesDelegate, 
					sh.PutBytesDelegate, sh.SeekDelegate, sh.CloseDelegate, sh.SizeDelegate, referenceHdc, 
					type, ref frameRect, frameUnit, description, out nativeObject);
			} else {
				status = GDIPlus.GdipRecordMetafileStreamI (new ComIStreamWrapper (stream), referenceHdc, 
					type, ref frameRect, frameUnit, description, out nativeObject);
			}
			GDIPlus.CheckStatus (status);
		}

		public Metafile (Stream stream, IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit, 
			EmfType type, string description) 
		{
			if (stream == null)
				throw new NullReferenceException ("stream");

			Status status = Status.NotImplemented;
			if (GDIPlus.RunningOnUnix ()) {
				// With libgdiplus we use a custom API for this, because there's no easy way
				// to get the Stream down to libgdiplus. So, we wrap the stream with a set of delegates.
				GDIPlus.GdiPlusStreamHelper sh = new GDIPlus.GdiPlusStreamHelper (stream, false);
				status = GDIPlus.GdipRecordMetafileFromDelegate_linux (sh.GetHeaderDelegate, sh.GetBytesDelegate, 
					sh.PutBytesDelegate, sh.SeekDelegate, sh.CloseDelegate, sh.SizeDelegate, referenceHdc, 
					type, ref frameRect, frameUnit, description, out nativeObject);
			} else {
				status = GDIPlus.GdipRecordMetafileStream (new ComIStreamWrapper (stream), referenceHdc, 
					type, ref frameRect, frameUnit, description, out nativeObject);
			}
			GDIPlus.CheckStatus (status);
		}

		public Metafile (string fileName, IntPtr referenceHdc, Rectangle frameRect, MetafileFrameUnit frameUnit, 
			EmfType type, string description) 
		{
			Status status = GDIPlus.GdipRecordMetafileFileNameI (fileName, referenceHdc, type, ref frameRect, 
				frameUnit, description, out nativeObject);
			GDIPlus.CheckStatus (status);
		}
		
		public Metafile (string fileName, IntPtr referenceHdc, RectangleF frameRect, MetafileFrameUnit frameUnit,
			EmfType type, string description) 
		{
			Status status = GDIPlus.GdipRecordMetafileFileName (fileName, referenceHdc, type, ref frameRect, frameUnit, 
				description, out nativeObject);
			GDIPlus.CheckStatus (status);
		}

		protected override void Dispose(bool disposing)
		{
			if (_metafileHolder != null && !_metafileHolder.Disposed)
			{
				// There's a graphics instance created from this Metafile,
				// transfer responsibility for disposing the nativeImage to the
				// MetafileHolder
				_metafileHolder.MetafileDisposed(nativeObject);
				_metafileHolder = null;
				nativeObject = IntPtr.Zero;
			}

			base.Dispose(disposing);
		}

		// methods

		public IntPtr GetHenhmetafile ()
		{
			return nativeObject;
		}

		[MonoLimitation ("Metafiles aren't only partially supported by libgdiplus.")]
		public MetafileHeader GetMetafileHeader ()
		{
			IntPtr header = Marshal.AllocHGlobal (Marshal.SizeOf (typeof (MetafileHeader)));
			try {
				Status status = GDIPlus.GdipGetMetafileHeaderFromMetafile (nativeObject, header);
				GDIPlus.CheckStatus (status);
				return new MetafileHeader (header);
			}
			finally {
				Marshal.FreeHGlobal (header);
			}
		}

		[MonoLimitation ("Metafiles aren't only partially supported by libgdiplus.")]
		public static MetafileHeader GetMetafileHeader (IntPtr henhmetafile)
		{
			IntPtr header = Marshal.AllocHGlobal (Marshal.SizeOf (typeof (MetafileHeader)));
			try {
				Status status = GDIPlus.GdipGetMetafileHeaderFromEmf (henhmetafile, header);
				GDIPlus.CheckStatus (status);
				return new MetafileHeader (header);
			}
			finally {
				Marshal.FreeHGlobal (header);
			}
		}

		[MonoLimitation ("Metafiles aren't only partially supported by libgdiplus.")]
		public static MetafileHeader GetMetafileHeader (Stream stream)
		{
			if (stream == null)
				throw new NullReferenceException ("stream");

			IntPtr header = Marshal.AllocHGlobal (Marshal.SizeOf (typeof (MetafileHeader)));
			try {
				Status status;

				if (GDIPlus.RunningOnUnix ()) {
					// With libgdiplus we use a custom API for this, because there's no easy way
					// to get the Stream down to libgdiplus. So, we wrap the stream with a set of delegates.
					GDIPlus.GdiPlusStreamHelper sh = new GDIPlus.GdiPlusStreamHelper (stream, false);
					status = GDIPlus.GdipGetMetafileHeaderFromDelegate_linux (sh.GetHeaderDelegate, 
						sh.GetBytesDelegate, sh.PutBytesDelegate, sh.SeekDelegate, sh.CloseDelegate, 
						sh.SizeDelegate, header);
				} else {
					status = GDIPlus.GdipGetMetafileHeaderFromStream (new ComIStreamWrapper (stream), header);
				}
				GDIPlus.CheckStatus (status);
				return new MetafileHeader (header);
			}
			finally {
				Marshal.FreeHGlobal (header);
			}
		}

		[MonoLimitation ("Metafiles aren't only partially supported by libgdiplus.")]
		public static MetafileHeader GetMetafileHeader (string fileName)
		{
			if (fileName == null)
				throw new ArgumentNullException ("fileName");

			IntPtr header = Marshal.AllocHGlobal (Marshal.SizeOf (typeof (MetafileHeader)));
			try {
				Status status = GDIPlus.GdipGetMetafileHeaderFromFile (fileName, header);
				GDIPlus.CheckStatus (status);
				return new MetafileHeader (header);
			}
			finally {
				Marshal.FreeHGlobal (header);
			}
		}

		[MonoLimitation ("Metafiles aren't only partially supported by libgdiplus.")]
		public static MetafileHeader GetMetafileHeader (IntPtr hmetafile, WmfPlaceableFileHeader wmfHeader)
		{
			IntPtr header = Marshal.AllocHGlobal (Marshal.SizeOf (typeof (MetafileHeader)));
			try {
				Status status = GDIPlus.GdipGetMetafileHeaderFromEmf (hmetafile, header);
				GDIPlus.CheckStatus (status);
				return new MetafileHeader (header);
			}
			finally {
				Marshal.FreeHGlobal (header);
			}
		}

		[MonoLimitation ("Metafiles aren't only partially supported by libgdiplus.")]
		public void PlayRecord (EmfPlusRecordType recordType, int flags, int dataSize, byte[] data)
		{
			Status status = GDIPlus.GdipPlayMetafileRecord (nativeObject, recordType, flags, dataSize, data);
			GDIPlus.CheckStatus (status);
		}
	}
}