/* mbed Microcontroller Library
 * Copyright (c) 2017-2017 ARM Limited
 * SPDX-License-Identifier: Apache-2.0
 *
 * 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.
 */

#ifndef IMPL_HCI_TRANSPORT_DRIVER_H_
#define IMPL_HCI_TRANSPORT_DRIVER_H_

#include <cstdint>

namespace ble {

/**
 * Base class of the HCI transport driver.
 * It allow the stack to write data in the HCI channel.
 */
class CordioHCITransportDriver {

    // hook for internal tests and passthrough driver
    friend class CordioHCIHook;

public:
    /**
     * Driver destructor.
     */
    virtual ~CordioHCITransportDriver() = default;

    /**
     * Inialization of the transport.
     */
    virtual void initialize() = 0;

    /**
     * termination of the transport.
     */
    virtual void terminate() = 0;

    /**
     * Write data in the transport channel.
     *
     * @param type The type of packet to transmit. It might be an HCI command
     * packet, ACL packet or EVT packet. Depending on the type of transport
     * it can prefix the packet itself.
     * @param len Number of bytes to transmit.
     * @param pData Pointer to the data to transmit. This is an WSF buffer
     * and if CORDIO_ZERO_COPY_HCI is enabled we receive ownership.
     *
     * @return The number of bytes which have been transmited.
     */
    virtual uint16_t write(uint8_t type, uint16_t len, uint8_t *pData) = 0;

    /**
     * The driver shall call this function whenever data bytes are received.
     *
     * @param data Pointer to the data received.
     * @param len Number of bytes received.
     */
    static void on_data_received(uint8_t* data, uint16_t len);

private:
    typedef void (*data_received_handler_t)(uint8_t* data, uint8_t len);

    static data_received_handler_t data_received_handler;

    static void set_data_received_handler(data_received_handler_t handler);
};

} // namespace ble

#endif /* IMPL_HCI_TRANSPORT_DRIVER_H_ */