/* Copyright (C) 2009-2010, Stefan Hacker <dD0t@users.sourceforge.net>
   Copyright (C) 2005-2010, Thorvald Natvig <thorvald@natvig.com>

   All rights reserved.

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions
   are met:

   - Redistributions of source code must retain the above copyright notice,
     this list of conditions and the following disclaimer.
   - Redistributions in binary form must reproduce the above copyright notice,
     this list of conditions and the following disclaimer in the documentation
     and/or other materials provided with the distribution.
   - Neither the name of the Mumble Developers nor the names of its
     contributors may be used to endorse or promote products derived from this
     software without specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#define _USE_MATH_DEFINES

#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
#include <tlhelp32.h>
#include <math.h>

#include "../mumble_plugin.h"

HANDLE h = NULL;

static DWORD getProcess(const wchar_t *exename) {
	PROCESSENTRY32 pe;
	DWORD pid = 0;

	pe.dwSize = sizeof(pe);
	HANDLE hSnap = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
	if (hSnap != INVALID_HANDLE_VALUE) {
		BOOL ok = Process32First(hSnap, &pe);

		while (ok) {
			if (wcscmp(pe.szExeFile, exename)==0) {
				pid = pe.th32ProcessID;
				break;
			}
			ok = Process32Next(hSnap, &pe);
		}
		CloseHandle(hSnap);
	}
	return pid;
}

static bool peekProc(VOID *base, VOID *dest, SIZE_T len) {
	SIZE_T r;
	BOOL ok=ReadProcessMemory(h, base, dest, len, &r);
	return (ok && (r == len));
}

static void about(HWND h) {
	::MessageBox(h, L"Reads audio position information from Wolfenstein: Enemy Territory (v2.60b)", L"Mumble W:ET plugin", MB_OK);
}

static int fetch(float *avatar_pos, float *avatar_front, float *avatar_top, float *camera_pos, float *camera_front, float *camera_top, std::string &context, std::wstring &identity) {
	float viewHor, viewVer;
	char state;

	for (int i=0;i<3;i++)
		avatar_pos[i] = avatar_front[i] = avatar_top[i] = camera_pos[i] = camera_front[i] = camera_top[i] = 0.0f;

	bool ok;

	/*
		This plugin uses the following Variables:

			Address			Type	Description
			===================================
			0x013F79CC		float	Y-Coordinate
			0x013E8CF4		float	X-Coordinate
			0x013E8CF8		float	Z-Coordinate
			0x013F9E20		float	Horizontal view
			0x013F9E1C		float	Vertical view
			0x013E8D18		byte	Magic value (32 ingame / 0 spectating)
	*/
	ok = peekProc((BYTE *) 0x013E8D18, &state, 1);
	if (! ok)
		return false;

	if (state != 32)
		return true; // If this magic value is !=32 we are spectating, so switch off PA

	ok = peekProc((BYTE *) 0x013F79CC, avatar_pos+1, 4) &&	//Y
	     peekProc((BYTE *) 0x013E8CF4, avatar_pos, 4) &&	//X
	     peekProc((BYTE *) 0x013E8CF8, avatar_pos+2, 4) && //Z
	     peekProc((BYTE *) 0x013F9E20, &viewHor, 4) && //Hor
	     peekProc((BYTE *) 0x013F9E1C, &viewVer, 4); //Ver

	if (! ok)
		return false;

	avatar_top[2] = -1; // Head movement is in front vector

	/*
	   Z-Value is increasing when heading north
				  decreasing when heading south
	   X-Value is increasing when heading east
				  decreasing when heading west
	   Y-Value is increasing when going up
				  decreasing when going down
	   1 unit = 1 meter (not confirmed)
	*/

	// Calculate view unit vector
	/*
	   Vertical view 0 when centered
				   -90 when looking up
				   +90 when looking down
	   Increasing when looking down.

	   Horizontal is 90 when facing north
					  0 when facing east
					-90 when facing south
					+/-180 when facing west
	   Increasing when turning left.
	*/
	viewVer *= static_cast<float>(M_PI / 180.0f);
	viewHor *= static_cast<float>(M_PI / 180.0f);

	avatar_front[0] = cos(viewVer) * cos(viewHor);
	avatar_front[1] = -sin(viewVer);
	avatar_front[2] = cos(viewVer) * sin(viewHor);

	for (int i=0;i<3;i++) {
		camera_pos[i] = avatar_pos[i];
		camera_front[i] = avatar_front[i];
		camera_top[i] = avatar_top[i];
	}

	return true;
}

static int trylock() {
	h = NULL;
	DWORD pid=getProcess(L"ET.exe");
	if (!pid)
		return false;

	h=OpenProcess(PROCESS_VM_READ, false, pid);
	if (!h)
		return false;

	float apos[3], afront[3], atop[3], cpos[3], cfront[3], ctop[3];
	std::string context;
	std::wstring identity;

	if (fetch(apos, afront, atop, cpos, cfront, ctop, context, identity))
		return true;

	CloseHandle(h);
	h = NULL;
	return false;
}

static void unlock() {
	if (h) {
		CloseHandle(h);
		h = NULL;
	}
}

static const std::wstring longdesc() {
	return std::wstring(L"Supports Wolfenstien: Enemy Territory v2.60b. No context or identity support yet.");
}

static std::wstring description(L"Wolfenstein: Enemy Territory v2.60b");
static std::wstring shortname(L"Wolfenstein: Enemy Territory");

static MumblePlugin wolfetplug = {
	MUMBLE_PLUGIN_MAGIC,
	description,
	shortname,
	about,
	NULL,
	trylock,
	unlock,
	longdesc,
	fetch
};

extern "C" __declspec(dllexport) MumblePlugin *getMumblePlugin() {
	return &wolfetplug;
}