Using Winamp input plugins for tagging audio files

using System;
using System.Runtime.InteropServices;
using System.Text;

// RightToCopy & PublishAndPerish: OrlandoCurioso 2007
// Ansi/Unicode SDK 5.32

namespace OC.Winamp
{
    internal abstract partial class Constants
    {
        public const int IN_VER = 0x100;
        public const int IN_VER_UNI = 0x0f000100;
        public const int IN_UNICODE = 0x0F000000;
        public const int GETFILEINFO_TITLE_LENGTH = 2048;
    }

    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
    internal delegate IntPtr GetInModulePtr();        //typedef In_Module*	(*WINAMPGETINMODULE2)( void );

    internal abstract partial class AnsiDelegates
    {
        [UnmanagedFunctionPointer(CallingConvention.Cdecl, CharSet= CharSet.Ansi)]
        public delegate int IntString(string fn);
        [UnmanagedFunctionPointer(CallingConvention.Cdecl, CharSet = CharSet.Ansi)]
        public delegate void GetFileInfo(string file, StringBuilder title, out int length_in_ms);
        [UnmanagedFunctionPointer(CallingConvention.Cdecl, CharSet = CharSet.Ansi)]
        public delegate int InfoBox(string file, IntPtr hwndParent);
    }

    internal abstract partial class UnicodeDelegates
    {
        [UnmanagedFunctionPointer(CallingConvention.Cdecl, CharSet = CharSet.Unicode)]
        public delegate int IntString(string fn);
        [UnmanagedFunctionPointer(CallingConvention.Cdecl, CharSet = CharSet.Unicode)]
        public delegate void GetFileInfo(string file, StringBuilder title, out int length_in_ms);
        [UnmanagedFunctionPointer(CallingConvention.Cdecl, CharSet = CharSet.Unicode)]
        public delegate int InfoBox(string file, IntPtr hwndParent);
    }

    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi, Size = 152)]
    internal class In_Module
    {
        public int version;				// module type (IN_VER or IN_VER_UNI)
        [MarshalAs(UnmanagedType.LPStr)]
        public string description;		// always ANSI
        public IntPtr hMainWindow;		// winamp's main window (filled in by winamp)
        public IntPtr hDllInstance;		// DLL instance handle  (filled in by winamp)
        [MarshalAs(UnmanagedType.LPStr)]
        public string FileExtensions;	// always ANSI
        public int is_seekable;
        public int UsesOutputPlug;

        public delegate void VoidIntPtrdelegate(IntPtr hwndParent);
        public delegate void VoidVoiddelegate();
        public delegate int IntVoiddelegate();
        public delegate void VoidIntdelegate(int value);
        public delegate int IntIntdelegate(int value);
        public delegate void EQSetdelegate(int on, [MarshalAs(UnmanagedType.LPArray, SizeConst = 10)] byte[] data, int preamp);

        [MarshalAs(UnmanagedType.FunctionPtr)]
        public VoidIntPtrdelegate Config;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public VoidIntPtrdelegate About;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public VoidVoiddelegate Init;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public VoidVoiddelegate Quit;
        public IntPtr GetFileInfo;              // GetFileInfodelegate
        public IntPtr InfoBox;                  // InfoBoxdelegate
        public IntPtr IsOurFile;                // IntStringdelegate
        public IntPtr Play;                     // IntStringdelegate
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public VoidVoiddelegate Pause;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public VoidVoiddelegate UnPause;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public IntVoiddelegate IsPaused;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public VoidVoiddelegate Stop;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public IntVoiddelegate GetLength;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public IntVoiddelegate GetOutputTime;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public IntIntdelegate SetOutputTime;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public VoidIntdelegate SetVolume;
        [MarshalAs(UnmanagedType.FunctionPtr)]
        public VoidIntdelegate SetPan;

        public IntPtr SAVSAInit;                 // all filled in by winamp, except EQSet
        public IntPtr SAVSADeInit;
        public IntPtr SAAddPCMData;
        public IntPtr SAGetMode;
        public IntPtr SAAdd;

        public IntPtr VSAAddPCMData;
        public IntPtr VSAGetMode;
        public IntPtr VSAAdd;
        public IntPtr VSASetInfo;

        public IntPtr dsp_isactive;
        public IntPtr dsp_dosamples;

        [MarshalAs(UnmanagedType.FunctionPtr)]
        public EQSetdelegate EQSet;

        public IntPtr SetInfo;
        public IntPtr outMod;
    }
}


#region in2.h / SDK 5.32

#if false

//#ifndef NULLSOFT_WINAMP_IN2H
//#define NULLSOFT_WINAMP_IN2H
//#include "out.h"

//// note: exported symbol is now winampGetInModule2.

//#define IN_UNICODE 0x0F000000

//#ifdef UNICODE_INPUT_PLUGIN
//#define in_char wchar_t
//#define IN_VER (IN_UNICODE | 0x100)
//#else
//#define in_char char
//#define IN_VER 0x100
//#endif

typedef struct 
{
	int version;				// module type (IN_VER)
	char *description;			// description of module, with version string

	HWND hMainWindow;			// winamp's main window (filled in by winamp)
	HINSTANCE hDllInstance;		// DLL instance handle (Also filled in by winamp)

	char *FileExtensions;		// "mp3\0Layer 3 MPEG\0mp2\0Layer 2 MPEG\0mpg\0Layer 1 MPEG\0"
								// May be altered from Config, so the user can select what they want
	
	int is_seekable;			// is this stream seekable? 
	int UsesOutputPlug;			// does this plug-in use the output plug-ins? (musn't ever change, ever :)

	void (*Config)(HWND hwndParent); // configuration dialog
	void (*About)(HWND hwndParent);  // about dialog

	void (*Init)();				// called at program init
	void (*Quit)();				// called at program quit

//#define GETFILEINFO_TITLE_LENGTH 2048 
	void (*GetFileInfo)(const in_char *file, in_char *title, int *length_in_ms); // if file == NULL, current playing is used
	int (*InfoBox)(const in_char *file, HWND hwndParent);
	
	int (*IsOurFile)(const in_char *fn);	// called before extension checks, to allow detection of mms://, etc
	// playback stuff
	int (*Play)(const in_char *fn);		// return zero on success, -1 on file-not-found, some other value on other (stopping winamp) error
	void (*Pause)();			// pause stream
	void (*UnPause)();			// unpause stream
	int (*IsPaused)();			// ispaused? return 1 if paused, 0 if not
	void (*Stop)();				// stop (unload) stream

	// time stuff
	int (*GetLength)();			// get length in ms
	int (*GetOutputTime)();		// returns current output time in ms. (usually returns outMod->GetOutputTime()
	void (*SetOutputTime)(int time_in_ms);	// seeks to point in stream (in ms). Usually you signal yoru thread to seek, which seeks and calls outMod->Flush()..

	// volume stuff
	void (*SetVolume)(int volume);	// from 0 to 255.. usually just call outMod->SetVolume
	void (*SetPan)(int pan);	// from -127 to 127.. usually just call outMod->SetPan
	
	// in-window builtin vis stuff

	void (*SAVSAInit)(int maxlatency_in_ms, int srate);		// call once in Play(). maxlatency_in_ms should be the value returned from outMod->Open()
	// call after opening audio device with max latency in ms and samplerate
	void (*SAVSADeInit)();	// call in Stop()


	// simple vis supplying mode
	void (*SAAddPCMData)(void *PCMData, int nch, int bps, int timestamp); 
											// sets the spec data directly from PCM data
											// quick and easy way to get vis working :)
											// needs at least 576 samples :)

	// advanced vis supplying mode, only use if you're cool. Use SAAddPCMData for most stuff.
	int (*SAGetMode)();		// gets csa (the current type (4=ws,2=osc,1=spec))
							// use when calling SAAdd()
	int (*SAAdd)(void *data, int timestamp, int csa); // sets the spec data, filled in by winamp


	// vis stuff (plug-in)
	// simple vis supplying mode
	void (*VSAAddPCMData)(void *PCMData, int nch, int bps, int timestamp); // sets the vis data directly from PCM data
											// quick and easy way to get vis working :)
											// needs at least 576 samples :)

	// advanced vis supplying mode, only use if you're cool. Use VSAAddPCMData for most stuff.
	int (*VSAGetMode)(int *specNch, int *waveNch); // use to figure out what to give to VSAAdd
	int (*VSAAdd)(void *data, int timestamp); // filled in by winamp, called by plug-in


	// call this in Play() to tell the vis plug-ins the current output params. 
	void (*VSASetInfo)(int srate, int nch); // <-- Correct (benski, dec 2005).. old declaration had the params backwards


	// dsp plug-in processing: 
	// (filled in by winamp, calld by input plug)

	// returns 1 if active (which means that the number of samples returned by dsp_dosamples
	// could be greater than went in.. Use it to estimate if you'll have enough room in the
	// output buffer
	int (*dsp_isactive)(); 

	// returns number of samples to output. This can be as much as twice numsamples. 
	// be sure to allocate enough buffer for samples, then.
	int (*dsp_dosamples)(short int *samples, int numsamples, int bps, int nch, int srate);


	// eq stuff
	void (*EQSet)(int on, char data[10], int preamp); // 0-64 each, 31 is +0, 0 is +12, 63 is -12. Do nothing to ignore.

	// info setting (filled in by winamp)
	void (*SetInfo)(int bitrate, int srate, int stereo, int synched); // if -1, changes ignored? :)

	Out_Module *outMod; // filled in by winamp, optionally used :)
} In_Module;

//#endif

#endif

#endregion