// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#pragma once

#include <ddk/usb/usb.h>
#include <ddktl/device.h>
#include <ddktl/protocol/empty-protocol.h>
#include <lib/zx/vmo.h>
#include <zircon/hw/usb-dfu.h>

namespace usb {

class Dfu;
using DfuBase = ddk::Device<Dfu, ddk::Messageable, ddk::Unbindable>;

class Dfu : public DfuBase,
            public ddk::EmptyProtocol<ZX_PROTOCOL_USB_TEST_FWLOADER> {

public:
    Dfu(zx_device_t* parent, const usb_protocol_t& usb,
        uint8_t intf_num, const usb_dfu_func_desc_t& func_desc)
        : DfuBase(parent),
          usb_(usb),
          intf_num_(intf_num),
          func_desc_(func_desc) {}

    // Spawns device node based on parent node.
    static zx_status_t Create(zx_device_t* parent);

    // Device protocol implementation.
    zx_status_t DdkMessage(fidl_msg_t* msg, fidl_txn_t* txn);
    void DdkUnbind() { DdkRemove(); }
    void DdkRelease() { delete this; }

    // FIDL message implementation.
    zx_status_t LoadFirmware(zx::vmo fw_vmo, size_t fw_size);

private:
    zx_status_t Bind();

    // Sends a USB control request to the device, and resets the control endpoint if stalled.
    // Returns ZX_OK if the request succeeded.
    zx_status_t ControlReq(uint8_t dir, uint8_t request, uint16_t value,
                           void* data, size_t length, size_t* out_length);

    // Downloads the data block to the device.
    // |block_num| should be incremented each time a block is transferred and range
    // from 0 to 65,535, wrapping around if necessary.
    // |len_to_write| is limited by the device max transfer size stored in |func_desc_|.
    zx_status_t Download(uint16_t block_num, uint8_t* buf, size_t len_to_write);
    // Stores the status data of the last download transfer into |out_status|.
    zx_status_t GetStatus(usb_dfu_get_status_data_t* out_status);
    // Sets the device status to OK and transitions the device to the DFU Idle state.
    zx_status_t ClearStatus();
    // Stores the current state of the device to |out_dfu_state|.
    zx_status_t GetState(uint8_t* out_dfu_state);

    const usb_protocol_t usb_;

    const uint8_t intf_num_;
    const usb_dfu_func_desc_t func_desc_;
};

}  // namespace usb