/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * X11 Display Control channel
 *
 * Copyright 2017 David Fort <contact@hardening-consulting.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <winpr/sysinfo.h>
#include <X11/Xutil.h>

#ifdef WITH_XRANDR
#include <X11/extensions/Xrandr.h>
#include <X11/extensions/randr.h>

#if (RANDR_MAJOR * 100 + RANDR_MINOR) >= 105
#	define USABLE_XRANDR
#endif

#endif

#include "xf_disp.h"
#include "xf_monitor.h"


#define TAG CLIENT_TAG("x11disp")
#define RESIZE_MIN_DELAY 200 /* minimum delay in ms between two resizes */

struct _xfDispContext
{
	xfContext *xfc;
	BOOL haveXRandr;
	int eventBase, errorBase;
	int lastSentWidth, lastSentHeight;
	UINT64 lastSentDate;
	int targetWidth, targetHeight;
	BOOL activated;
	BOOL waitingResize;
};


static BOOL xf_disp_sendResize(xfDispContext *xfDisp, int width, int height)
{
	DISPLAY_CONTROL_MONITOR_LAYOUT layout;
	xfContext *xfc = xfDisp->xfc;
	rdpSettings *settings = xfc->context.settings;

	xfDisp->lastSentDate = GetTickCount64();
	xfDisp->lastSentWidth = width;
	xfDisp->lastSentHeight = height;
	xfDisp->waitingResize = TRUE;

	layout.Flags = DISPLAY_CONTROL_MONITOR_PRIMARY;
	layout.Top = layout.Left = 0;
	layout.Width = width;
	layout.Height = height;
	layout.Orientation = ORIENTATION_LANDSCAPE;
	layout.DesktopScaleFactor = settings->DesktopScaleFactor;
	layout.DeviceScaleFactor = settings->DeviceScaleFactor;
	layout.PhysicalWidth = width;
	layout.PhysicalHeight = height;

	return xfc->disp->SendMonitorLayout(xfc->disp, 1, &layout) == CHANNEL_RC_OK;
}


static BOOL xf_disp_set_window_resizable(xfDispContext *xfDisp)
{
	XSizeHints *size_hints;

	if (!(size_hints = XAllocSizeHints()))
		return FALSE;

	size_hints->flags = PMinSize | PMaxSize | PWinGravity;
	size_hints->win_gravity = NorthWestGravity;
	size_hints->min_width = size_hints->min_height = 320;
	size_hints->max_width = size_hints->max_height = 8192;
	XSetWMNormalHints(xfDisp->xfc->display, xfDisp->xfc->window->handle, size_hints);
	XFree(size_hints);
	return TRUE;
}


static void xf_disp_OnActivated(rdpContext* context, ActivatedEventArgs* e)
{
	xfContext *xfc = (xfContext *)context;
	xfDispContext *xfDisp = xfc->xfDisp;
	rdpSettings *settings = context->settings;

	xfDisp->waitingResize = FALSE;

	if (xfDisp->activated && !settings->Fullscreen)
	{
		xf_disp_set_window_resizable(xfDisp);

		if (e->firstActivation)
			return;

		/* if a resize has been done recently don't do anything and let the timer
		 * perform the resize */
		if (GetTickCount64() - xfDisp->lastSentDate < RESIZE_MIN_DELAY)
			return;

		if ((xfDisp->lastSentWidth != xfDisp->targetWidth) || (xfDisp->lastSentHeight != xfDisp->targetHeight))
		{
			WLog_DBG(TAG, "performing delayed resize to %dx%d", xfDisp->targetWidth, xfDisp->targetHeight);
			xf_disp_sendResize(xfDisp, xfDisp->targetWidth, xfDisp->targetHeight);
		}
	}
}


static void xf_disp_OnGraphicsReset(rdpContext* context, GraphicsResetEventArgs* e)
{
	xfContext *xfc = (xfContext *)context;
	xfDispContext *xfDisp = xfc->xfDisp;
	rdpSettings *settings = context->settings;

	xfDisp->waitingResize = FALSE;

	if (xfDisp->activated && !settings->Fullscreen)
	{
		xf_disp_set_window_resizable(xfDisp);

		/* if a resize has been done recently don't do anything and let the timer
		 * perform the resize */
		if (GetTickCount64() - xfDisp->lastSentDate < RESIZE_MIN_DELAY)
			return;

		if ((xfDisp->lastSentWidth != xfDisp->targetWidth) || (xfDisp->lastSentHeight != xfDisp->targetHeight))
		{
			WLog_DBG(TAG, "performing delayed resize to %dx%d", xfDisp->targetWidth, xfDisp->targetHeight);
			xf_disp_sendResize(xfDisp, xfDisp->targetWidth, xfDisp->targetHeight);
		}
	}
}

static void xf_disp_OnTimer(rdpContext* context, TimerEventArgs* e)
{
	xfContext *xfc = (xfContext *)context;
	xfDispContext *xfDisp = xfc->xfDisp;
	rdpSettings *settings = context->settings;

	if (!xfDisp->activated || settings->Fullscreen)
		return;

	if (e->now - xfDisp->lastSentDate < RESIZE_MIN_DELAY)
		return;

	if ((xfDisp->lastSentWidth != xfDisp->targetWidth) || (xfDisp->lastSentHeight != xfDisp->targetHeight))
	{
		WLog_DBG(TAG, "timer performing delayed resize to %dx%d", xfDisp->targetWidth, xfDisp->targetHeight);
		xf_disp_sendResize(xfDisp, xfDisp->targetWidth, xfDisp->targetHeight);
	}
}

xfDispContext *xf_disp_new(xfContext* xfc)
{
	xfDispContext *ret = calloc(1, sizeof(xfDispContext));
	if (!ret)
		return NULL;

	ret->xfc = xfc;
#ifdef USABLE_XRANDR
	if (XRRQueryExtension(xfc->display, &ret->eventBase, &ret->errorBase))
	{
		ret->haveXRandr = TRUE;
	}
#endif
	ret->lastSentWidth = ret->targetWidth = xfc->context.settings->DesktopWidth;
	ret->lastSentHeight = ret->targetHeight = xfc->context.settings->DesktopHeight;

	PubSub_SubscribeActivated(xfc->context.pubSub, (pActivatedEventHandler)xf_disp_OnActivated);
	PubSub_SubscribeGraphicsReset(xfc->context.pubSub, (pGraphicsResetEventHandler)xf_disp_OnGraphicsReset);
	PubSub_SubscribeTimer(xfc->context.pubSub, (pTimerEventHandler)xf_disp_OnTimer);
	return ret;
}

void xf_disp_free(xfDispContext *disp)
{
	PubSub_UnsubscribeActivated(disp->xfc->context.pubSub, (pActivatedEventHandler)xf_disp_OnActivated);
	PubSub_UnsubscribeTimer(disp->xfc->context.pubSub, (pTimerEventHandler)xf_disp_OnTimer);
	free(disp);
}

static UINT xf_disp_sendLayout(DispClientContext *disp, rdpMonitor *monitors, int nmonitors)
{
	UINT ret = CHANNEL_RC_OK;
	DISPLAY_CONTROL_MONITOR_LAYOUT *layouts;
	int i;
	xfDispContext *xfDisp = (xfDispContext *)disp->custom;
	rdpSettings *settings = xfDisp->xfc->context.settings;

	layouts = calloc(nmonitors, sizeof(DISPLAY_CONTROL_MONITOR_LAYOUT));
	if (!layouts)
		return CHANNEL_RC_NO_MEMORY;

	for (i = 0; i < nmonitors; i++)
	{
		layouts[i].Flags = (monitors[i].is_primary ? DISPLAY_CONTROL_MONITOR_PRIMARY : 0);
		layouts[i].Left = monitors[i].x;
		layouts[i].Top = monitors[i].y;
		layouts[i].Width = monitors[i].width;
		layouts[i].Height = monitors[i].height;
		layouts[i].Orientation = ORIENTATION_LANDSCAPE;
		layouts[i].PhysicalWidth = monitors[i].attributes.physicalWidth;
		layouts[i].PhysicalHeight = monitors[i].attributes.physicalHeight;

		switch(monitors[i].attributes.orientation)
		{
		case 90:
			layouts[i].Orientation = ORIENTATION_PORTRAIT;
			break;
		case 180:
			layouts[i].Orientation = ORIENTATION_LANDSCAPE_FLIPPED;
			break;
		case 270:
			layouts[i].Orientation = ORIENTATION_PORTRAIT_FLIPPED;
			break;
		case 0:
		default:
			/* MS-RDPEDISP - 2.2.2.2.1:
			 * Orientation (4 bytes): A 32-bit unsigned integer that specifies the
			 * orientation of the monitor in degrees. Valid values are 0, 90, 180
			 * or 270
			 *
			 * So we default to ORIENTATION_LANDSCAPE
			 */
			layouts[i].Orientation = ORIENTATION_LANDSCAPE;
			break;
		}
		layouts[i].DesktopScaleFactor = settings->DesktopScaleFactor;
		layouts[i].DeviceScaleFactor = settings->DeviceScaleFactor;
	}

	ret = disp->SendMonitorLayout(disp, nmonitors, layouts);

	free(layouts);

	return ret;
}

BOOL xf_disp_handle_xevent(xfContext *xfc, XEvent *event)
{
	xfDispContext *xfDisp = xfc->xfDisp;
	rdpSettings *settings = xfc->context.settings;
	UINT32 maxWidth, maxHeight;

	if (!xfDisp->haveXRandr)
		return TRUE;

#ifdef USABLE_XRANDR
	if (event->type != xfDisp->eventBase + RRScreenChangeNotify)
		return TRUE;
#endif

	xf_detect_monitors(xfc, &maxWidth, &maxHeight);
	return xf_disp_sendLayout(xfc->disp, settings->MonitorDefArray, settings->MonitorCount) == CHANNEL_RC_OK;
}


BOOL xf_disp_handle_configureNotify(xfContext *xfc, int width, int height)
{
	xfDispContext *xfDisp = xfc->xfDisp;

	if (xfDisp->lastSentWidth == width && xfDisp->lastSentHeight == height)
		return TRUE;

	if (xfDisp->waitingResize || !xfDisp->activated ||
			(GetTickCount64() - xfDisp->lastSentDate < RESIZE_MIN_DELAY))
	{
		WLog_DBG(TAG, "delaying resize to %dx%d", width, height);
		xfDisp->targetWidth = width;
		xfDisp->targetHeight = height;
		return TRUE;
	}

	WLog_DBG(TAG, "resizing on ConfigureNotify to %dx%d", width, height);
	return xf_disp_sendResize(xfDisp, width, height);
}


UINT xf_DisplayControlCaps(DispClientContext *disp, UINT32 maxNumMonitors, UINT32 maxMonitorAreaFactorA, UINT32 maxMonitorAreaFactorB)
{
	/* we're called only if dynamic resolution update is activated */
	xfDispContext *xfDisp = (xfDispContext *)disp->custom;
	rdpSettings *settings = xfDisp->xfc->context.settings;

	WLog_DBG(TAG, "DisplayControlCapsPdu: MaxNumMonitors: %"PRIu32" MaxMonitorAreaFactorA: %"PRIu32" MaxMonitorAreaFactorB: %"PRIu32"",
	       maxNumMonitors, maxMonitorAreaFactorA, maxMonitorAreaFactorB);

	xfDisp->activated = TRUE;

	if (settings->Fullscreen)
		return CHANNEL_RC_OK;

	WLog_DBG(TAG, "DisplayControlCapsPdu: setting the window as resizeable");
	return xf_disp_set_window_resizable(xfDisp) ? CHANNEL_RC_OK : CHANNEL_RC_NO_MEMORY;
}

BOOL xf_disp_init(xfContext* xfc, DispClientContext *disp)
{
	rdpSettings *settings = xfc->context.settings;
	xfc->disp = disp;
	disp->custom = (void*) xfc->xfDisp;

	if (settings->DynamicResolutionUpdate)
	{
		disp->DisplayControlCaps = xf_DisplayControlCaps;
#ifdef USABLE_XRANDR
		if (settings->Fullscreen)
		{
			/* ask X11 to notify us of screen changes */
			XRRSelectInput(xfc->display, DefaultRootWindow(xfc->display), RRScreenChangeNotifyMask);
		}
#endif
	}

	return TRUE;
}

