#ifndef FLATUSB_USB_DRIVER_INTERFACE
#define FLATUSB_USB_DRIVER_INTERFACE

#include <stdbool.h>
#include <stdint.h>

typedef enum {
    USB_SPD_UKWN = 0,
    USB_SPD_LOW = 1,
    USB_SPD_FULL = 2,
    USB_SPD_HIGH = 3
} UsbDrv_LineSpeed;

typedef void (*UsbDrv_IN_cb)(uint8_t ep);

/**
 * USB Driver interface.
 */
typedef struct {
    // USB CORE -> USB DRIVER
    void (*init)();                                                    ///< Initialize USB driver
    void (*reset)();                                                   ///< Reset USB driver
    void (*stall)(uint8_t ep, uint8_t dir, bool stall);                ///< Stall the endpoint
    uint32_t (*arm_IN)(uint8_t ep, const uint8_t *data, uint16_t len); ///< Arm IN endpoint
    uint32_t (*arm_OUT)(uint8_t ep, uint16_t len);                     ///< Arm OUT endpoint
    void (*set_address)(uint8_t addr);                                 ///< Set device address
    void (*set_config)(uint8_t ci);                                    ///< Make the chosen setting operational
    void (*autoarm)(uint8_t ep);                                       ///< Enable OUT autoarm
    void (*en_ep_irq)(uint8_t ep, uint8_t dir, bool en);               ///< Enable endpoint interrupt
    void (*reg_IN_cb)(uint8_t ep, UsbDrv_IN_cb cb);                    ///< Register a callback for IN transaction complete

    // USB DRIVER -> USB CORE
    void (*rst_notify)();             ///< Notify USB core of a bus issued reset
    void (*enum_notify)(uint8_t spd); ///< Notify the USB core that speed negotiation has concluded
} UsbDrv_DrvIntf;

#ifndef USBDBGMSG
#define USBMSG(...)
#endif

/**
 * Callback codes.
 */
typedef enum {
    USB_CBC_OUT,          ///< OUT done!
    USB_CBC_IN_DONE,      ///< IN done!
    USB_CBC_IN_FIFOEMPTY, ///< Could not serve IN request, since Tx FIFO was empty
} UsbDrv_CallbackCode;

/**
 * Callback compound.
 */
typedef struct {
    uint8_t ep : 4;      ///< Endpoint number
    uint8_t dir : 1;     ///< Direction
    uint8_t code : 3;    ///< Event code
    uint16_t size;       ///< Data size
    const uint8_t *data; ///< Data
} UsbDrv_CallbackCompound;

/**
 * Control transfer stages.
 */
typedef enum { UST_SETUP, ///< Setup stage
               UST_DATA   ///< Data stage
} UsbDrv_ControlTfStage;

#endif /* FLATUSB_USB_DRIVER_INTERFACE */