/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

#ifndef GUAC_RDP_CHANNELS_RDPDR_H
#define GUAC_RDP_CHANNELS_RDPDR_H

#include "config.h"
#include "channels/common-svc.h"

#include <freerdp/freerdp.h>
#include <guacamole/client.h>

/**
 * The maximum number of bytes to allow for a device read.
 */
#define GUAC_RDP_MAX_READ_BUFFER 4194304

/**
 * Arbitrary device forwarded over the RDPDR channel.
 */
typedef struct guac_rdpdr_device guac_rdpdr_device;

/**
 * Handler for client device list announce. Each implementing device must write
 * its announcement header and data to the given output stream.
 */
typedef void guac_rdpdr_device_announce_handler(guac_rdp_common_svc* svc,
        guac_rdpdr_device* device, wStream* output_stream, int device_id);

/**
 * Handler for device I/O requests.
 */
typedef void guac_rdpdr_device_iorequest_handler(guac_rdp_common_svc* svc,
        guac_rdpdr_device* device, wStream* input_stream, int file_id,
        int completion_id, int major_func, int minor_func);

/**
 * Handler for cleaning up the dynamically-allocated portions of a device.
 */
typedef void guac_rdpdr_device_free_handler(guac_rdp_common_svc* svc,
        guac_rdpdr_device* device);

struct guac_rdpdr_device {

    /**
     * The ID assigned to this device by the RDPDR plugin.
     */
    int device_id;

    /**
     * Device name, used for logging and for passthrough to the
     * server.
     */
    const char* device_name;

    /**
     * The type of RDPDR device that this represents.
     */
    uint32_t device_type;

    /**
     * The DOS name of the device.  Max 8 bytes, including terminator.
     */
    const char *dos_name;
    
    /**
     * The stream that stores the RDPDR device announcement for this device.
     */
    wStream* device_announce;
    
    /**
     * The length of the device_announce wStream.
     */
    int device_announce_len;

    /**
     * Handler which should be called for every I/O request received.
     */
    guac_rdpdr_device_iorequest_handler* iorequest_handler;

    /**
     * Handler which should be called when the device is being freed.
     */
    guac_rdpdr_device_free_handler* free_handler;

    /**
     * Arbitrary data, used internally by the handlers for this device.
     */
    void* data;

};

/**
 * Structure representing the current state of the Guacamole RDPDR plugin for
 * FreeRDP.
 */
typedef struct guac_rdpdr {

    /**
     * The number of devices registered within the devices array.
     */
    int devices_registered;

    /**
     * Array of registered devices.
     */
    guac_rdpdr_device devices[8];

} guac_rdpdr;

/**
 * Creates a new stream which contains the common DR_DEVICE_IOCOMPLETION header
 * used for virtually all responses.
 */
wStream* guac_rdpdr_new_io_completion(guac_rdpdr_device* device,
        int completion_id, int status, int size);

/**
 * Begins streaming the given file to the user via a Guacamole file stream.
 */
void guac_rdpdr_start_download(guac_rdp_common_svc* svc,
        guac_rdpdr_device* device, char* path);

/**
 * Initializes device redirection support (file transfer, printing, etc.) for
 * RDP and handling of the RDPDR channel.  If failures occur, messages noting
 * the specifics of those failures will be logged, and the RDP side of
 * device redirection support will not be functional.
 *
 * This MUST be called within the PreConnect callback of the freerdp instance
 * for RDPDR support to be loaded.
 *
 * @param rdpContext
 *     The rdpContext associated with the FreeRDP side of the RDP connection.
 */
void guac_rdpdr_load_plugin(rdpContext* context);

/**
 * Handler which is invoked when the RDPDR channel is connected to the RDP
 * server.
 */
guac_rdp_common_svc_connect_handler guac_rdpdr_process_connect;

/**
 * Handler which is invoked when the RDPDR channel has received data from the
 * RDP server.
 */
guac_rdp_common_svc_receive_handler guac_rdpdr_process_receive;

/**
 * Handler which is invoked when the RDPDR channel has disconnected and is
 * about to be freed.
 */
guac_rdp_common_svc_terminate_handler guac_rdpdr_process_terminate;

#endif