/*  LilyPad - Pad plugin for PS2 Emulator
 *  Copyright (C) 2002-2014  PCSX2 Dev Team/ChickenLiver
 *
 *  PCSX2 is free software: you can redistribute it and/or modify it under the
 *  terms of the GNU Lesser General Public License as published by the Free
 *  Software Found- ation, either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  PCSX2 is distributed in the hope that it will be useful, but WITHOUT ANY
 *  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 *  FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 *  details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with PCSX2.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "Global.h"
#include "WndProcEater.h"

WndProcEater::WndProcEater()
{
    hWndEaten = 0;
    eatenWndProc = 0;

    extraProcs = 0;
    numExtraProcs = 0;

    hMutex = CreateMutex(0, 0, L"LilyPad");
}

WndProcEater::~WndProcEater() throw()
{
    if (hMutex) {
        ReleaseMutex(hMutex);
        CloseHandle(hMutex);
    }
}

void WndProcEater::ReleaseExtraProc(ExtraWndProc proc)
{
    // Probably isn't needed, but just in case...
    if (hMutex)
        WaitForSingleObject(hMutex, 100);

    //printf( "(Lilypad) Regurgitating! -> 0x%x\n", proc );

    for (int i = 0; i < numExtraProcs; i++) {
        if (extraProcs[i].proc == proc) {
            extraProcs[i] = extraProcs[--numExtraProcs];
            break;
        }
    }
    if (!numExtraProcs && eatenWndProc) {
        free(extraProcs);
        extraProcs = 0;
        // As numExtraProcs is 0, won't cause recursion if called from Release().
        Release();
    }
}

void WndProcEater::Release()
{
    while (numExtraProcs)
        ReleaseExtraProc(extraProcs[0].proc);
    if (hWndEaten && IsWindow(hWndEaten)) {
        RemoveProp(hWndEaten, L"LilyHaxxor");
        SetWindowLongPtr(hWndEaten, GWLP_WNDPROC, (LONG_PTR)eatenWndProc);
        hWndEaten = 0;
        eatenWndProc = 0;
    }
}

LRESULT WndProcEater::_OverrideWndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    if (hWnd != hWndEaten)
        fprintf(stderr, "Totally mismatched window handles on OverrideWndProc!\n");

    ExtraWndProcResult res = CONTINUE_BLISSFULLY;
    LRESULT out = 0;
    // Here because want it for binding, even when no keyboard mode is selected.
    if (uMsg == WM_GETDLGCODE) {
        return DLGC_WANTALLKEYS | CallWindowProc(eatenWndProc, hWnd, uMsg, wParam, lParam);
    }

    for (int i = 0; i < numExtraProcs; i++) {
        // Note:  Second bit of deviceUpdateQueued is only set when I receive a device change
        // notification, which is handled in the GS thread in one of the extraProcs, so this
        // is all I need to prevent bad things from happening while updating devices.  No mutex needed.
        // if ((deviceUpdateQueued&2) && (extraProcs[i].flags & EATPROC_NO_UPDATE_WHILE_UPDATING_DEVICES)) continue;

        ExtraWndProcResult res2 = extraProcs[i].proc(hWnd, uMsg, wParam, lParam, &out);
        if (res2 != res) {
            if (res2 == CONTINUE_BLISSFULLY_AND_RELEASE_PROC) {
                ReleaseExtraProc(extraProcs[i].proc);
                i--;
            } else if (res2 > res)
                res = res2;
        }
    }

    if (res != NO_WND_PROC) {
        if (out == WM_DESTROY) {
            Release();
        }
        if (res == CONTINUE_BLISSFULLY)
            out = CallWindowProc(eatenWndProc, hWnd, uMsg, wParam, lParam);
        else if (res == USE_DEFAULT_WND_PROC)
            out = DefWindowProc(hWnd, uMsg, wParam, lParam);
    }
    return out;
}

static LRESULT CALLBACK OverrideWndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    WndProcEater *obj = (WndProcEater *)GetProp(hWnd, L"LilyHaxxor");
    return (obj == NULL) ?
               DefWindowProc(hWnd, uMsg, wParam, lParam) :
               obj->_OverrideWndProc(hWnd, uMsg, wParam, lParam);
}

bool WndProcEater::SetWndHandle(HWND hWnd)
{
    if (hWnd == hWndEaten)
        return true;

    //printf( "(Lilypad) (Re)-Setting window handle! -> this=0x%08x, hWnd=0x%08x\n", this, hWnd );

    Release();
    SetProp(hWnd, L"LilyHaxxor", (HANDLE) this);

    eatenWndProc = (WNDPROC)SetWindowLongPtr(hWnd, GWLP_WNDPROC, (LONG_PTR)OverrideWndProc);
    hWndEaten = (eatenWndProc) ? hWnd : 0;

    return !!hWndEaten;
}

void WndProcEater::Eat(ExtraWndProc proc, DWORD flags)
{

    // check if Subclassing failed to init during SetWndHandle
    if (!hWndEaten)
        return;

    // Probably isn't needed, but just in case...
    if (hMutex)
        WaitForSingleObject(hMutex, 100);

    //printf( "(Lilypad) EatingWndProc! -> 0x%x\n", proc );

    extraProcs = (ExtraWndProcInfo *)realloc(extraProcs, sizeof(ExtraWndProcInfo) * (numExtraProcs + 1));
    extraProcs[numExtraProcs].proc = proc;
    extraProcs[numExtraProcs].flags = flags;
    numExtraProcs++;
}