/**
 * FreeRDP: A Remote Desktop Protocol Implementation
 * Serial Port Device Service Virtual Channel
 *
 * Copyright 2011 O.S. Systems Software Ltda.
 * Copyright 2011 Eduardo Fiss Beloni <beloni@ossystems.com.br>
 *
 * 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 <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#ifdef HAVE_SYS_MODEM_H
#include <sys/modem.h>
#endif
#ifdef HAVE_SYS_FILIO_H
#include <sys/filio.h>
#endif
#ifdef HAVE_SYS_STRTIO_H
#include <sys/strtio.h>
#endif
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#include "serial_tty.h"
#include "serial_constants.h"

#include <winpr/crt.h>
#include <winpr/synch.h>
#include <winpr/thread.h>
#include <winpr/stream.h>
#include <winpr/collections.h>

#include <freerdp/freerdp.h>
#include <freerdp/utils/list.h>
#include <freerdp/channels/rdpdr.h>
#include <freerdp/utils/svc_plugin.h>

typedef struct _SERIAL_DEVICE SERIAL_DEVICE;

struct _SERIAL_DEVICE
{
	DEVICE device;

	char* path;
	SERIAL_TTY* tty;

	HANDLE thread;
	wMessageQueue* IrpQueue;
};

static void serial_process_irp_create(SERIAL_DEVICE* serial, IRP* irp)
{
	int status;
	UINT32 FileId;
	UINT32 PathLength;
	SERIAL_TTY* tty;
	char* path = NULL;

	Stream_Seek_UINT32(irp->input); /* DesiredAccess (4 bytes) */
	Stream_Seek_UINT64(irp->input); /* AllocationSize (8 bytes) */
	Stream_Seek_UINT32(irp->input); /* FileAttributes (4 bytes) */
	Stream_Seek_UINT32(irp->input); /* SharedAccess (4 bytes) */
	Stream_Seek_UINT32(irp->input); /* CreateDisposition (4 bytes) */
	Stream_Seek_UINT32(irp->input); /* CreateOptions (4 bytes) */

	Stream_Read_UINT32(irp->input, PathLength);

	status = ConvertFromUnicode(CP_UTF8, 0, (WCHAR*) Stream_Pointer(irp->input),
			PathLength / 2, &path, 0, NULL, NULL);

	if (status < 1)
		path = (char*) calloc(1, 1);

	FileId = irp->devman->id_sequence++;

	tty = serial_tty_new(serial->path, FileId);

	if (!tty)
	{
		irp->IoStatus = STATUS_UNSUCCESSFUL;
		FileId = 0;

		DEBUG_WARN("failed to create %s", path);
	}
	else
	{
		serial->tty = tty;
		DEBUG_SVC("%s(%d) created.", serial->path, FileId);
	}

	Stream_Write_UINT32(irp->output, FileId);
	Stream_Write_UINT8(irp->output, 0);

	free(path);

	irp->Complete(irp);
}

static void serial_process_irp_close(SERIAL_DEVICE* serial, IRP* irp)
{
	SERIAL_TTY* tty;

	tty = serial->tty;

	if (!tty)
	{
		irp->IoStatus = STATUS_UNSUCCESSFUL;
		DEBUG_WARN("tty not valid.");
	}
	else
	{
		DEBUG_SVC("%s(%d) closed.", serial->path, tty->id);

		serial_tty_free(tty);
		serial->tty = NULL;
	}

	Stream_Zero(irp->output, 5); /* Padding (5 bytes) */

	irp->Complete(irp);
}

static void serial_process_irp_read(SERIAL_DEVICE* serial, IRP* irp)
{
	SERIAL_TTY* tty;
	UINT32 Length;
	UINT64 Offset;
	BYTE* buffer = NULL;

	Stream_Read_UINT32(irp->input, Length);
	Stream_Read_UINT64(irp->input, Offset);

	DEBUG_SVC("length %u offset %llu", Length, Offset);

	tty = serial->tty;

	if (!tty)
	{
		irp->IoStatus = STATUS_UNSUCCESSFUL;
		Length = 0;

		DEBUG_WARN("tty not valid.");
	}
	else
	{
		buffer = (BYTE*) malloc(Length);

		if (!serial_tty_read(tty, buffer, &Length))
		{
			irp->IoStatus = STATUS_UNSUCCESSFUL;
			free(buffer);
			buffer = NULL;
			Length = 0;

			DEBUG_WARN("read %s(%d) failed.", serial->path, tty->id);
		}
		else
		{
			DEBUG_SVC("read %llu-%llu from %d", Offset, Offset + Length, tty->id);
		}
	}

	Stream_Write_UINT32(irp->output, Length);

	if (Length > 0)
	{
		Stream_EnsureRemainingCapacity(irp->output, Length);
		Stream_Write(irp->output, buffer, Length);
	}

	free(buffer);

	irp->Complete(irp);
}

static void serial_process_irp_write(SERIAL_DEVICE* serial, IRP* irp)
{
	SERIAL_TTY* tty;
	UINT32 Length;
	UINT64 Offset;

	Stream_Read_UINT32(irp->input, Length);
	Stream_Read_UINT64(irp->input, Offset);
	Stream_Seek(irp->input, 20); /* Padding */

	DEBUG_SVC("length %u offset %llu", Length, Offset);

	tty = serial->tty;

	if (!tty)
	{
		irp->IoStatus = STATUS_UNSUCCESSFUL;
		Length = 0;

		DEBUG_WARN("tty not valid.");
	}
	else if (!serial_tty_write(tty, Stream_Pointer(irp->input), Length))
	{
		irp->IoStatus = STATUS_UNSUCCESSFUL;
		Length = 0;

		DEBUG_WARN("write %s(%d) failed.", serial->path, tty->id);
	}
	else
	{
		DEBUG_SVC("write %llu-%llu to %s(%d).", Offset, Offset + Length, serial->path, tty->id);
	}

	Stream_Write_UINT32(irp->output, Length);
	Stream_Write_UINT8(irp->output, 0); /* Padding */

	irp->Complete(irp);
}

static void serial_process_irp_device_control(SERIAL_DEVICE* serial, IRP* irp)
{
	SERIAL_TTY* tty;
	UINT32 IoControlCode;
	UINT32 InputBufferLength;
	UINT32 OutputBufferLength;
	UINT32 abortIo = SERIAL_ABORT_IO_NONE;

	Stream_Read_UINT32(irp->input, InputBufferLength);
	Stream_Read_UINT32(irp->input, OutputBufferLength);
	Stream_Read_UINT32(irp->input, IoControlCode);
	Stream_Seek(irp->input, 20); /* Padding */

	tty = serial->tty;

	if (!tty)
	{
		irp->IoStatus = STATUS_UNSUCCESSFUL;
		OutputBufferLength = 0;

		DEBUG_WARN("tty not valid.");
	}
	else
	{
		irp->IoStatus = serial_tty_control(tty, IoControlCode, irp->input, irp->output, &abortIo);
	}

	irp->Complete(irp);
}

static void serial_process_irp(SERIAL_DEVICE* serial, IRP* irp)
{
	DEBUG_SVC("MajorFunction %u", irp->MajorFunction);

	switch (irp->MajorFunction)
	{
		case IRP_MJ_CREATE:
			serial_process_irp_create(serial, irp);
			break;

		case IRP_MJ_CLOSE:
			serial_process_irp_close(serial, irp);
			break;

		case IRP_MJ_READ:
			serial_process_irp_read(serial, irp);
			break;

		case IRP_MJ_WRITE:
			serial_process_irp_write(serial, irp);
			break;

		case IRP_MJ_DEVICE_CONTROL:
			serial_process_irp_device_control(serial, irp);
			break;

		default:
			DEBUG_WARN("MajorFunction 0x%X not supported", irp->MajorFunction);
			irp->IoStatus = STATUS_NOT_SUPPORTED;
			irp->Complete(irp);
			break;
	}
}

static void* serial_thread_func(void* arg)
{
	IRP* irp;
	wMessage message;
	SERIAL_DEVICE* drive = (SERIAL_DEVICE*) arg;

	while (1)
	{
		if (!MessageQueue_Wait(drive->IrpQueue))
			break;

		if (!MessageQueue_Peek(drive->IrpQueue, &message, TRUE))
			break;

		if (message.id == WMQ_QUIT)
			break;

		irp = (IRP*) message.wParam;

		if (irp)
			serial_process_irp(drive, irp);
	}

	ExitThread(0);
	return NULL;
}

static void serial_irp_request(DEVICE* device, IRP* irp)
{
	SERIAL_DEVICE* serial = (SERIAL_DEVICE*) device;
	MessageQueue_Post(serial->IrpQueue, NULL, 0, (void*) irp, NULL);
}

static void serial_free(DEVICE* device)
{
	SERIAL_DEVICE* serial = (SERIAL_DEVICE*) device;

	DEBUG_SVC("freeing device");

	MessageQueue_PostQuit(serial->IrpQueue, 0);
	WaitForSingleObject(serial->thread, INFINITE);
	CloseHandle(serial->thread);

	serial_tty_free(serial->tty);

	/* Clean up resources */
	Stream_Free(serial->device.data, TRUE);
	MessageQueue_Free(serial->IrpQueue);

	free(serial);
}

#ifdef STATIC_CHANNELS
#define DeviceServiceEntry	serial_DeviceServiceEntry
#endif

int DeviceServiceEntry(PDEVICE_SERVICE_ENTRY_POINTS pEntryPoints)
{
	int i, len;
	char* name;
	char* path;
	RDPDR_SERIAL* device;
	SERIAL_DEVICE* serial;

	device = (RDPDR_SERIAL*) pEntryPoints->device;
	name = device->Name;
	path = device->Path;

	if (!name || (name[0] == '*'))
	{
		/* TODO: implement auto detection of parallel ports */
		return 0;
	}

	if ((name && name[0]) && (path && path[0]))
	{
		serial = (SERIAL_DEVICE*) calloc(1, sizeof(SERIAL_DEVICE));

		if (!serial)
			return -1;

		serial->device.type = RDPDR_DTYP_SERIAL;
		serial->device.name = name;
		serial->device.IRPRequest = serial_irp_request;
		serial->device.Free = serial_free;

		len = strlen(name);
		serial->device.data = Stream_New(NULL, len + 1);

		for (i = 0; i <= len; i++)
			Stream_Write_UINT8(serial->device.data, name[i] < 0 ? '_' : name[i]);

		serial->path = path;
		serial->IrpQueue = MessageQueue_New(NULL);

		pEntryPoints->RegisterDevice(pEntryPoints->devman, (DEVICE*) serial);

		serial->thread = CreateThread(NULL, 0, 
				(LPTHREAD_START_ROUTINE) serial_thread_func, (void*) serial, 0, NULL);
	}

	return 0;
}