//-----------------------------------------------------------------------------
//
// Copyright 1993-1996 id Software
// Copyright 1999-2016 Randy Heit
// Copyright 2002-2016 Christoph Oelckers
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 2 of the License, or
// (at your option) any later version.
//
// This program 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 this program.  If not, see http://www.gnu.org/licenses/
//
//
//----------------------------------------------------------------------------- 

#include "c_bind.h"
#include "d_event.h"
#include "d_gui.h"
#include "inputstate.h"

int eventhead;
int eventtail;
event_t events[NUM_EVENTS];

//==========================================================================
//
// G_Responder
// Process the event for the game
//
//==========================================================================

bool G_Responder (event_t *ev)
{
#if 0
	// any other key pops up menu if in demos
	// [RH] But only if the key isn't bound to a "special" command
	if (gameaction == ga_nothing && 
		(demoplayback || gamestate == GS_DEMOSCREEN || gamestate == GS_TITLELEVEL))
	{
		const char *cmd = Bindings.GetBind (ev->data1);

		if (ev->type == EV_KeyDown)
		{

			if (!cmd || (
				strnicmp (cmd, "menu_", 5) &&
				stricmp (cmd, "toggleconsole") &&
				stricmp (cmd, "sizeup") &&
				stricmp (cmd, "sizedown") &&
				stricmp (cmd, "togglemap") &&
				stricmp (cmd, "spynext") &&
				stricmp (cmd, "spyprev") &&
				stricmp (cmd, "chase") &&
				stricmp (cmd, "+showscores") &&
				stricmp (cmd, "bumpgamma") &&
				stricmp (cmd, "screenshot")))
			{
				M_StartControlPanel(true);
				M_SetMenu(NAME_Mainmenu, -1);
				return true;
			}
			else
			{
				return C_DoKey (ev, &Bindings, &DoubleBindings);
			}
		}
		if (cmd && cmd[0] == '+')
			return C_DoKey (ev, &Bindings, &DoubleBindings);

		return false;
	}
#endif

#if 0
	if (gamestate == GS_LEVEL)
	{
		if (ST_Responder (ev))
			return true;		// status window ate it
		if (!viewactive && primaryLevel->automap->Responder (ev, false))
			return true;		// automap ate it
	}
	else if (gamestate == GS_FINALE)
	{
		if (F_Responder (ev))
			return true;		// finale ate the event
	}
#endif

	switch (ev->type)
	{
	case EV_KeyDown:
		if (C_DoKey (ev, &Bindings, &DoubleBindings))
			return true;
		break;

	case EV_KeyUp:
		C_DoKey (ev, &Bindings, &DoubleBindings);
		break;

#if 0
	// [RH] mouse buttons are sent as key up/down events
	case EV_Mouse: 
		mousex = (int)(ev->x * mouse_sensitivity);
		mousey = (int)(ev->y * mouse_sensitivity);
		break;
#endif
	}

	// [RH] If the view is active, give the automap a chance at
	// the events *last* so that any bound keys get precedence.

#if 0
	if (gamestate == GS_LEVEL && viewactive && primaryLevel->automap)
		return primaryLevel->automap->Responder (ev, true);
#endif

	return (ev->type == EV_KeyDown ||
			ev->type == EV_Mouse);
}


//==========================================================================
//
// D_ProcessEvents
//
// Send all the events of the given timestamp down the responder chain.
// Events are asynchronous inputs generally generated by the game user.
// Events can be discarded if no responder claims them
//
//==========================================================================

void D_ProcessEvents (void)
{
	event_t *ev;
	for (; eventtail != eventhead ; eventtail = (eventtail+1)&(NUM_EVENTS-1))
	{
		ev = &events[eventtail];
		if (ev->type == EV_None)
			continue;
		if (ev->type == EV_DeviceChange)
			(void)0;//UpdateJoystickMenu(I_UpdateDeviceList());
#if 0
		if (C_Responder (ev))
			continue;				// console ate the event
		if (M_Responder (ev))
			continue;				// menu ate the event
#endif
		G_Responder (ev);
	}
}

//==========================================================================
//
// D_PostEvent
//
// Called by the I/O functions when input is detected.
//
//==========================================================================

void D_PostEvent (const event_t *ev)
{
	// Do not post duplicate consecutive EV_DeviceChange events.
	if (ev->type == EV_DeviceChange && events[eventhead].type == EV_DeviceChange)
	{
		return;
	}
	events[eventhead] = *ev;
#if 0 // No idea if this can be made to work ever... For now, pass on the mouse movement event so that the input code can deal with them itself.
	if (ev->type == EV_Mouse && menuactive == MENU_Off && ConsoleState != c_down && ConsoleState != c_falling && !primaryLevel->localEventManager->Responder(ev) && !paused)
	{
		if (Button_Mlook.bDown || freelook)
		{
			int look = int(ev->y * m_pitch * mouse_sensitivity * 16.0);
			if (invertmouse)
				look = -look;
			G_AddViewPitch (look, true);
			events[eventhead].y = 0;
		}
		if (!Button_Strafe.bDown && !lookstrafe)
		{
			G_AddViewAngle (int(ev->x * m_yaw * mouse_sensitivity * 8.0), true);
			events[eventhead].x = 0;
		}
		if ((events[eventhead].x | events[eventhead].y) == 0)
		{
			return;
		}
	}
#endif
	
	// Add the key to the global keyboard state.
	// This is probably the biggest roadblock with the input system as it undermines a proper event driven approach.
	// Too much code depends on just checking this instead of waiting for events to happen.
	// Here's also definitely not the best place to maintain the keyboard state but right now it's unavoidable to do this outside the event processing because so much code depends on it.
	// Once all those busy waiting loops can poll the event queue for a proper skip event, this will mostly go away.
	inputState.AddEvent(ev);
	
	// Also add it to the event queue - this is where everything should transition to eventually.
	eventhead = (eventhead+1)&(NUM_EVENTS-1);
}

//==========================================================================
//
// D_RemoveNextCharEvent
//
// Removes the next EV_GUI_Char event in the input queue. Used by the menu,
// since it (generally) consumes EV_GUI_KeyDown events and not EV_GUI_Char
// events, and it needs to ensure that there is no left over input when it's
// done. If there are multiple EV_GUI_KeyDowns before the EV_GUI_Char, then
// there are dead chars involved, so those should be removed, too. We do
// this by changing the message type to EV_None rather than by actually
// removing the event from the queue.
// 
//==========================================================================

void D_RemoveNextCharEvent()
{
	assert(events[eventtail].type == EV_GUI_Event && events[eventtail].subtype == EV_GUI_KeyDown);
	for (int evnum = eventtail; evnum != eventhead; evnum = (evnum+1) & (NUM_EVENTS-1))
	{
		event_t *ev = &events[evnum];
		if (ev->type != EV_GUI_Event)
			break;
		if (ev->subtype == EV_GUI_KeyDown || ev->subtype == EV_GUI_Char)
		{
			ev->type = EV_None;
			if (ev->subtype == EV_GUI_Char)
				break;
		}
		else
		{
			break;
		}
	}
}