/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * Geometry tracking Virtual Channel Extension
 *
 * 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.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <winpr/crt.h>
#include <winpr/synch.h>
#include <winpr/interlocked.h>
#include <winpr/print.h>
#include <winpr/stream.h>
#include <winpr/cmdline.h>
#include <winpr/collections.h>

#include <freerdp/addin.h>
#include <freerdp/client/geometry.h>
#include <freerdp/channels/log.h>

#define TAG CHANNELS_TAG("geometry.client")

#include "geometry_main.h"

struct _GEOMETRY_CHANNEL_CALLBACK
{
	IWTSVirtualChannelCallback iface;

	IWTSPlugin* plugin;
	IWTSVirtualChannelManager* channel_mgr;
	IWTSVirtualChannel* channel;
};
typedef struct _GEOMETRY_CHANNEL_CALLBACK GEOMETRY_CHANNEL_CALLBACK;

struct _GEOMETRY_LISTENER_CALLBACK
{
	IWTSListenerCallback iface;

	IWTSPlugin* plugin;
	IWTSVirtualChannelManager* channel_mgr;
	GEOMETRY_CHANNEL_CALLBACK* channel_callback;
};
typedef struct _GEOMETRY_LISTENER_CALLBACK GEOMETRY_LISTENER_CALLBACK;

struct _GEOMETRY_PLUGIN
{
	IWTSPlugin iface;

	IWTSListener* listener;
	GEOMETRY_LISTENER_CALLBACK* listener_callback;

	GeometryClientContext* context;
};
typedef struct _GEOMETRY_PLUGIN GEOMETRY_PLUGIN;

static UINT32 mappedGeometryHash(UINT64* g)
{
	return (UINT32)((*g >> 32) + (*g & 0xffffffff));
}

static BOOL mappedGeometryKeyCompare(UINT64* g1, UINT64* g2)
{
	return *g1 == *g2;
}

void mappedGeometryRef(MAPPED_GEOMETRY* g)
{
	InterlockedIncrement(&g->refCounter);
}

void mappedGeometryUnref(MAPPED_GEOMETRY* g)
{
	if (InterlockedDecrement(&g->refCounter))
		return;

	g->MappedGeometryUpdate = NULL;
	g->MappedGeometryClear = NULL;
	g->custom = NULL;
	free(g->geometry.rects);
	free(g);
}

static void freerdp_rgndata_reset(FREERDP_RGNDATA* data)
{
	data->nRectCount = 0;
}

static UINT32 geometry_read_RGNDATA(wStream* s, UINT32 len, FREERDP_RGNDATA* rgndata)
{
	UINT32 dwSize, iType;
	INT32 right, bottom;
	INT32 x, y, w, h;

	if (len < 32)
	{
		WLog_ERR(TAG, "invalid RGNDATA");
		return ERROR_INVALID_DATA;
	}

	Stream_Read_UINT32(s, dwSize);

	if (dwSize != 32)
	{
		WLog_ERR(TAG, "invalid RGNDATA dwSize");
		return ERROR_INVALID_DATA;
	}

	Stream_Read_UINT32(s, iType);

	if (iType != RDH_RECTANGLE)
	{
		WLog_ERR(TAG, "iType %" PRIu32 " for RGNDATA is not supported", iType);
		return ERROR_UNSUPPORTED_TYPE;
	}

	Stream_Read_UINT32(s, rgndata->nRectCount);
	Stream_Seek_UINT32(s); /* nRgnSize IGNORED */
	Stream_Read_INT32(s, x);
	Stream_Read_INT32(s, y);
	Stream_Read_INT32(s, right);
	Stream_Read_INT32(s, bottom);
	if ((abs(x) > INT16_MAX) || (abs(y) > INT16_MAX))
		return ERROR_INVALID_DATA;
	w = right - x;
	h = bottom - y;
	if ((abs(w) > INT16_MAX) || (abs(h) > INT16_MAX))
		return ERROR_INVALID_DATA;
	rgndata->boundingRect.x = (INT16)x;
	rgndata->boundingRect.y = (INT16)y;
	rgndata->boundingRect.width = (INT16)w;
	rgndata->boundingRect.height = (INT16)h;
	len -= 32;

	if (len / (4 * 4) < rgndata->nRectCount)
	{
		WLog_ERR(TAG, "not enough data for region rectangles");
	}

	if (rgndata->nRectCount)
	{
		UINT32 i;
		RDP_RECT* tmp = realloc(rgndata->rects, rgndata->nRectCount * sizeof(RDP_RECT));

		if (!tmp)
		{
			WLog_ERR(TAG, "unable to allocate memory for %" PRIu32 " RECTs", rgndata->nRectCount);
			return CHANNEL_RC_NO_MEMORY;
		}
		rgndata->rects = tmp;

		for (i = 0; i < rgndata->nRectCount; i++)
		{
			Stream_Read_INT32(s, x);
			Stream_Read_INT32(s, y);
			Stream_Read_INT32(s, right);
			Stream_Read_INT32(s, bottom);
			if ((abs(x) > INT16_MAX) || (abs(y) > INT16_MAX))
				return ERROR_INVALID_DATA;
			w = right - x;
			h = bottom - y;
			if ((abs(w) > INT16_MAX) || (abs(h) > INT16_MAX))
				return ERROR_INVALID_DATA;
			rgndata->rects[i].x = (INT16)x;
			rgndata->rects[i].y = (INT16)y;
			rgndata->rects[i].width = (INT16)w;
			rgndata->rects[i].height = (INT16)h;
		}
	}

	return CHANNEL_RC_OK;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
static UINT geometry_recv_pdu(GEOMETRY_CHANNEL_CALLBACK* callback, wStream* s)
{
	UINT32 length, cbGeometryBuffer;
	MAPPED_GEOMETRY* mappedGeometry;
	GEOMETRY_PLUGIN* geometry;
	GeometryClientContext* context;
	UINT ret = CHANNEL_RC_OK;
	UINT32 version, updateType, geometryType;
	UINT64 id;

	geometry = (GEOMETRY_PLUGIN*)callback->plugin;
	context = (GeometryClientContext*)geometry->iface.pInterface;

	if (Stream_GetRemainingLength(s) < 4)
	{
		WLog_ERR(TAG, "not enough remaining data");
		return ERROR_INVALID_DATA;
	}

	Stream_Read_UINT32(s, length); /* Length (4 bytes) */

	if (length < 73 || Stream_GetRemainingLength(s) < (length - 4))
	{
		WLog_ERR(TAG, "invalid packet length");
		return ERROR_INVALID_DATA;
	}

	Stream_Read_UINT32(s, version);
	Stream_Read_UINT64(s, id);
	Stream_Read_UINT32(s, updateType);
	Stream_Seek_UINT32(s); /* flags */

	mappedGeometry = HashTable_GetItemValue(context->geometries, &id);

	if (updateType == GEOMETRY_CLEAR)
	{
		if (!mappedGeometry)
		{
			WLog_ERR(TAG, "geometry 0x%" PRIx64 " not found here, ignoring clear command", id);
			return CHANNEL_RC_OK;
		}

		WLog_DBG(TAG, "clearing geometry 0x%" PRIx64 "", id);

		if (mappedGeometry->MappedGeometryClear &&
		    !mappedGeometry->MappedGeometryClear(mappedGeometry))
			return ERROR_INTERNAL_ERROR;

		if (!HashTable_Remove(context->geometries, &id))
			WLog_ERR(TAG, "geometry not removed from geometries");
	}
	else if (updateType == GEOMETRY_UPDATE)
	{
		BOOL newOne = FALSE;

		if (!mappedGeometry)
		{
			newOne = TRUE;
			WLog_DBG(TAG, "creating geometry 0x%" PRIx64 "", id);
			mappedGeometry = calloc(1, sizeof(MAPPED_GEOMETRY));
			if (!mappedGeometry)
				return CHANNEL_RC_NO_MEMORY;

			mappedGeometry->refCounter = 1;
			mappedGeometry->mappingId = id;

			if (HashTable_Add(context->geometries, &(mappedGeometry->mappingId), mappedGeometry) <
			    0)
			{
				WLog_ERR(TAG, "unable to register geometry 0x%" PRIx64 " in the table", id);
				free(mappedGeometry);
				return CHANNEL_RC_NO_MEMORY;
			}
		}
		else
		{
			WLog_DBG(TAG, "updating geometry 0x%" PRIx64 "", id);
		}

		Stream_Read_UINT64(s, mappedGeometry->topLevelId);

		Stream_Read_INT32(s, mappedGeometry->left);
		Stream_Read_INT32(s, mappedGeometry->top);
		Stream_Read_INT32(s, mappedGeometry->right);
		Stream_Read_INT32(s, mappedGeometry->bottom);

		Stream_Read_INT32(s, mappedGeometry->topLevelLeft);
		Stream_Read_INT32(s, mappedGeometry->topLevelTop);
		Stream_Read_INT32(s, mappedGeometry->topLevelRight);
		Stream_Read_INT32(s, mappedGeometry->topLevelBottom);

		Stream_Read_UINT32(s, geometryType);

		Stream_Read_UINT32(s, cbGeometryBuffer);
		if (Stream_GetRemainingLength(s) < cbGeometryBuffer)
		{
			WLog_ERR(TAG, "invalid packet length");
			return ERROR_INVALID_DATA;
		}

		if (cbGeometryBuffer)
		{
			ret = geometry_read_RGNDATA(s, cbGeometryBuffer, &mappedGeometry->geometry);
			if (ret != CHANNEL_RC_OK)
				return ret;
		}
		else
		{
			freerdp_rgndata_reset(&mappedGeometry->geometry);
		}

		if (newOne)
		{
			if (context->MappedGeometryAdded &&
			    !context->MappedGeometryAdded(context, mappedGeometry))
			{
				WLog_ERR(TAG, "geometry added callback failed");
				ret = ERROR_INTERNAL_ERROR;
			}
		}
		else
		{
			if (mappedGeometry->MappedGeometryUpdate &&
			    !mappedGeometry->MappedGeometryUpdate(mappedGeometry))
			{
				WLog_ERR(TAG, "geometry update callback failed");
				ret = ERROR_INTERNAL_ERROR;
			}
		}
	}
	else
	{
		WLog_ERR(TAG, "unknown updateType=%" PRIu32 "", updateType);
		ret = CHANNEL_RC_OK;
	}

	return ret;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
static UINT geometry_on_data_received(IWTSVirtualChannelCallback* pChannelCallback, wStream* data)
{
	GEOMETRY_CHANNEL_CALLBACK* callback = (GEOMETRY_CHANNEL_CALLBACK*)pChannelCallback;
	return geometry_recv_pdu(callback, data);
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
static UINT geometry_on_close(IWTSVirtualChannelCallback* pChannelCallback)
{
	free(pChannelCallback);
	return CHANNEL_RC_OK;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
static UINT geometry_on_new_channel_connection(IWTSListenerCallback* pListenerCallback,
                                               IWTSVirtualChannel* pChannel, BYTE* Data,
                                               BOOL* pbAccept,
                                               IWTSVirtualChannelCallback** ppCallback)
{
	GEOMETRY_CHANNEL_CALLBACK* callback;
	GEOMETRY_LISTENER_CALLBACK* listener_callback = (GEOMETRY_LISTENER_CALLBACK*)pListenerCallback;

	WINPR_UNUSED(Data);
	WINPR_UNUSED(pbAccept);

	callback = (GEOMETRY_CHANNEL_CALLBACK*)calloc(1, sizeof(GEOMETRY_CHANNEL_CALLBACK));

	if (!callback)
	{
		WLog_ERR(TAG, "calloc failed!");
		return CHANNEL_RC_NO_MEMORY;
	}

	callback->iface.OnDataReceived = geometry_on_data_received;
	callback->iface.OnClose = geometry_on_close;
	callback->plugin = listener_callback->plugin;
	callback->channel_mgr = listener_callback->channel_mgr;
	callback->channel = pChannel;
	listener_callback->channel_callback = callback;
	*ppCallback = (IWTSVirtualChannelCallback*)callback;
	return CHANNEL_RC_OK;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
static UINT geometry_plugin_initialize(IWTSPlugin* pPlugin, IWTSVirtualChannelManager* pChannelMgr)
{
	UINT status;
	GEOMETRY_PLUGIN* geometry = (GEOMETRY_PLUGIN*)pPlugin;
	geometry->listener_callback =
	    (GEOMETRY_LISTENER_CALLBACK*)calloc(1, sizeof(GEOMETRY_LISTENER_CALLBACK));

	if (!geometry->listener_callback)
	{
		WLog_ERR(TAG, "calloc failed!");
		return CHANNEL_RC_NO_MEMORY;
	}

	geometry->listener_callback->iface.OnNewChannelConnection = geometry_on_new_channel_connection;
	geometry->listener_callback->plugin = pPlugin;
	geometry->listener_callback->channel_mgr = pChannelMgr;
	status =
	    pChannelMgr->CreateListener(pChannelMgr, GEOMETRY_DVC_CHANNEL_NAME, 0,
	                                &geometry->listener_callback->iface, &(geometry->listener));
	geometry->listener->pInterface = geometry->iface.pInterface;
	return status;
}

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
static UINT geometry_plugin_terminated(IWTSPlugin* pPlugin)
{
	GEOMETRY_PLUGIN* geometry = (GEOMETRY_PLUGIN*)pPlugin;
	GeometryClientContext* context = (GeometryClientContext*)geometry->iface.pInterface;

	if (geometry && geometry->listener_callback)
	{
		IWTSVirtualChannelManager* mgr = geometry->listener_callback->channel_mgr;
		if (mgr)
			IFCALL(mgr->DestroyListener, mgr, geometry->listener);
	}

	if (context)
		HashTable_Free(context->geometries);

	free(geometry->listener_callback);
	free(geometry->iface.pInterface);
	free(pPlugin);
	return CHANNEL_RC_OK;
}

/**
 * Channel Client Interface
 */

#ifdef BUILTIN_CHANNELS
#define DVCPluginEntry geometry_DVCPluginEntry
#else
#define DVCPluginEntry FREERDP_API DVCPluginEntry
#endif

/**
 * Function description
 *
 * @return 0 on success, otherwise a Win32 error code
 */
UINT DVCPluginEntry(IDRDYNVC_ENTRY_POINTS* pEntryPoints)
{
	UINT error = CHANNEL_RC_OK;
	GEOMETRY_PLUGIN* geometry;
	GeometryClientContext* context;
	geometry = (GEOMETRY_PLUGIN*)pEntryPoints->GetPlugin(pEntryPoints, "geometry");

	if (!geometry)
	{
		geometry = (GEOMETRY_PLUGIN*)calloc(1, sizeof(GEOMETRY_PLUGIN));

		if (!geometry)
		{
			WLog_ERR(TAG, "calloc failed!");
			return CHANNEL_RC_NO_MEMORY;
		}

		geometry->iface.Initialize = geometry_plugin_initialize;
		geometry->iface.Connected = NULL;
		geometry->iface.Disconnected = NULL;
		geometry->iface.Terminated = geometry_plugin_terminated;
		context = (GeometryClientContext*)calloc(1, sizeof(GeometryClientContext));

		if (!context)
		{
			WLog_ERR(TAG, "calloc failed!");
			goto error_context;
		}

		context->geometries = HashTable_New(FALSE);
		context->geometries->hash = (HASH_TABLE_HASH_FN)mappedGeometryHash;
		context->geometries->keyCompare = (HASH_TABLE_KEY_COMPARE_FN)mappedGeometryKeyCompare;
		context->geometries->valueFree = (HASH_TABLE_VALUE_FREE_FN)mappedGeometryUnref;

		context->handle = (void*)geometry;
		geometry->iface.pInterface = (void*)context;
		geometry->context = context;
		error = pEntryPoints->RegisterPlugin(pEntryPoints, "geometry", (IWTSPlugin*)geometry);
	}
	else
	{
		WLog_ERR(TAG, "could not get geometry Plugin.");
		return CHANNEL_RC_BAD_CHANNEL;
	}

	return error;

error_context:
	free(geometry);
	return CHANNEL_RC_NO_MEMORY;
}