//
// Copyright 2010-2014 Ettus Research LLC
// Copyright 2018 Ettus Research, a National Instruments Company
//
// SPDX-License-Identifier: GPL-3.0-or-later
//

#ifndef INCLUDED_LIBUHD_TRANSPORT_LIBUSB_HPP
#define INCLUDED_LIBUHD_TRANSPORT_LIBUSB_HPP

#include <uhd/config.hpp>
#include <uhd/transport/usb_device_handle.hpp>
#include <uhd/utils/noncopyable.hpp>
#include <libusb.h>
#include <memory>

//! Define LIBUSB_CALL when its missing (non-windows)
#ifndef LIBUSB_CALL
#    define LIBUSB_CALL
#endif /*LIBUSB_CALL*/

//! libusb_handle_events_timeout_completed is only in newer API
#ifndef HAVE_LIBUSB_HANDLE_EVENTS_TIMEOUT_COMPLETED
#    define libusb_handle_events_timeout_completed(ctx, tx, completed) \
        libusb_handle_events_timeout(ctx, tx)
#endif /* HAVE_LIBUSB_HANDLE_EVENTS_TIMEOUT_COMPLETED */

//! libusb_error_name is only in newer API
#ifndef HAVE_LIBUSB_ERROR_NAME
#    define libusb_error_name(code) str(boost::format("LIBUSB_ERROR_CODE %d") % code)
#endif /* HAVE_LIBUSB_ERROR_NAME */

//! libusb_strerror is only in newer API
#ifndef HAVE_LIBUSB_STRERROR
#    define libusb_strerror(code) libusb_error_name(code)
#endif /* HAVE_LIBUSB_STRERROR */

/***********************************************************************
 * Libusb object oriented smart pointer wrappers:
 * The following wrappers provide allocation and automatic deallocation
 * for various libusb data types and handles. The construction routines
 * also store tables of already allocated structures to avoid multiple
 * occurrences of opened handles (for example).
 **********************************************************************/
namespace uhd { namespace transport { namespace libusb {

/*!
 * This session class holds a global libusb context for this process.
 * The get global session call will create a new context if none exists.
 * When all references to session are destroyed, the context will be freed.
 */
class session : uhd::noncopyable
{
public:
    typedef std::shared_ptr<session> sptr;

    virtual ~session(void);

    /*!
     *   Level 0: no messages ever printed by the library (default)
     *   Level 1: error messages are printed to stderr
     *   Level 2: warning and error messages are printed to stderr
     *   Level 3: informational messages are printed to stdout, warning
     *            and error messages are printed to stderr
     */
    static const int debug_level = 0;

    //! get a shared pointer to the global session
    static sptr get_global_session(void);

    //! get the underlying libusb context pointer
    virtual libusb_context* get_context(void) const = 0;
};

/*!
 * Holds a device pointer with a reference to the session.
 */
class device : uhd::noncopyable
{
public:
    typedef std::shared_ptr<device> sptr;

    virtual ~device(void);

    //! get the underlying device pointer
    virtual libusb_device* get(void) const = 0;
};

/*!
 * This device list class holds a device list that will be
 * automatically freed when the last reference is destroyed.
 */
class device_list : uhd::noncopyable
{
public:
    typedef std::shared_ptr<device_list> sptr;

    virtual ~device_list(void);

    //! make a new device list
    static sptr make(void);

    //! the number of devices in this list
    virtual size_t size() const = 0;

    //! get the device pointer at a particular index
    virtual device::sptr at(size_t index) const = 0;
};

/*!
 * Holds a device descriptor and a reference to the device.
 */
class device_descriptor : uhd::noncopyable
{
public:
    typedef std::shared_ptr<device_descriptor> sptr;

    virtual ~device_descriptor(void);

    //! make a new descriptor from a device reference
    static sptr make(device::sptr);

    //! get the underlying device descriptor
    virtual const libusb_device_descriptor& get(void) const = 0;

    virtual std::string get_ascii_property(const std::string& what) const = 0;
};

/*!
 * Holds a device handle and a reference to the device.
 */
class device_handle : uhd::noncopyable
{
public:
    typedef std::shared_ptr<device_handle> sptr;

    virtual ~device_handle(void);

    //! get a cached handle or make a new one given the device
    static sptr get_cached_handle(device::sptr);

    //! get the underlying device handle
    virtual libusb_device_handle* get(void) const = 0;

    /*!
     * Open USB interfaces for control using magic value
     * IN interface:      2
     * OUT interface:     1
     * Control interface: 0
     */
    virtual void claim_interface(int) = 0;

    virtual void clear_endpoints(
        unsigned char recv_endpoint, unsigned char send_endpoint) = 0;

    virtual void reset_device(void) = 0;
};

/*!
 * The special handle is our internal implementation of the
 * usb device handle which is used publicly to identify a device.
 */
class special_handle : public usb_device_handle
{
public:
    typedef std::shared_ptr<special_handle> sptr;

    ~special_handle(void) override;

    //! make a new special handle from device
    static sptr make(device::sptr);

    //! get the underlying device reference
    virtual device::sptr get_device(void) const = 0;
};

}}} // namespace uhd::transport::libusb

#endif /* INCLUDED_LIBUHD_TRANSPORT_LIBUSB_HPP */
