#include "project.h"

static const struct usb_endpoint_descriptor comm_endp[] = {
  {
    .bLength = USB_DT_ENDPOINT_SIZE,
    .bDescriptorType = USB_DT_ENDPOINT,
    .bEndpointAddress = 0x83,
    .bmAttributes = USB_ENDPOINT_ATTR_INTERRUPT,
    .wMaxPacketSize = 16,
    .bInterval = 255,
  }
};

static const struct usb_endpoint_descriptor data_endp[] = {
  {
    .bLength = USB_DT_ENDPOINT_SIZE,
    .bDescriptorType = USB_DT_ENDPOINT,
    .bEndpointAddress = 0x01,
    .bmAttributes = USB_ENDPOINT_ATTR_BULK,
    .wMaxPacketSize = 64,
    .bInterval = 1,
  },
  {
    .bLength = USB_DT_ENDPOINT_SIZE,
    .bDescriptorType = USB_DT_ENDPOINT,
    .bEndpointAddress = 0x82,
    .bmAttributes = USB_ENDPOINT_ATTR_BULK,
    .wMaxPacketSize = 64,
    .bInterval = 1,
  }
};

static const struct {
  struct usb_cdc_header_descriptor header;
  struct usb_cdc_call_management_descriptor call_mgmt;
  struct usb_cdc_acm_descriptor acm;
  struct usb_cdc_union_descriptor cdc_union;
} __attribute__((packed)) cdcacm_functional_descriptors = {
  .header = {
    .bFunctionLength = sizeof(struct usb_cdc_header_descriptor),
    .bDescriptorType = CS_INTERFACE,
    .bDescriptorSubtype = USB_CDC_TYPE_HEADER,
    .bcdCDC = 0x0110,
  },
  .call_mgmt = {
    .bFunctionLength = 
    sizeof(struct usb_cdc_call_management_descriptor),
    .bDescriptorType = CS_INTERFACE,
    .bDescriptorSubtype = USB_CDC_TYPE_CALL_MANAGEMENT,
    .bmCapabilities = 0,
    .bDataInterface = 1,
  },
  .acm = {
    .bFunctionLength = sizeof(struct usb_cdc_acm_descriptor),
    .bDescriptorType = CS_INTERFACE,
    .bDescriptorSubtype = USB_CDC_TYPE_ACM,
    .bmCapabilities = 0,
  },
  .cdc_union = {
    .bFunctionLength = sizeof(struct usb_cdc_union_descriptor),
    .bDescriptorType = CS_INTERFACE,
    .bDescriptorSubtype = USB_CDC_TYPE_UNION,
    .bControlInterface = 0,
    .bSubordinateInterface0 = 1, 
  }
};

const struct usb_interface_descriptor comm_iface[] = {
  {
    .bLength = USB_DT_INTERFACE_SIZE,
    .bDescriptorType = USB_DT_INTERFACE,
    .bInterfaceNumber = 0,
    .bAlternateSetting = 0,
    .bNumEndpoints = 1,
    .bInterfaceClass = USB_CLASS_CDC,
    .bInterfaceSubClass = USB_CDC_SUBCLASS_ACM,
    .bInterfaceProtocol = USB_CDC_PROTOCOL_AT,
    .iInterface = 0,
    .endpoint = comm_endp,
    .extra = &cdcacm_functional_descriptors,
    .extralen = sizeof(cdcacm_functional_descriptors)
  }
};

const struct usb_interface_descriptor data_iface[] = {
  {
    .bLength = USB_DT_INTERFACE_SIZE,
    .bDescriptorType = USB_DT_INTERFACE,
    .bInterfaceNumber = 1,
    .bAlternateSetting = 0,
    .bNumEndpoints = 2,
    .bInterfaceClass = USB_CLASS_DATA,
    .bInterfaceSubClass = 0,
    .bInterfaceProtocol = 0,
    .iInterface = 0,
    .endpoint = data_endp,
  }
};


int cdcacm_control_request(usbd_device *usbd_dev,
				  struct usb_setup_data *req,
				  uint8_t **buf,
				  uint16_t *len,
				  int (**complete)(usbd_device *usbd_dev,
						    struct usb_setup_data *req))
{
  (void)complete;
  (void)buf;
  (void)usbd_dev;

  switch(req->bRequest) {
  case USB_CDC_REQ_SET_CONTROL_LINE_STATE: {
    /*
     * This Linux cdc_acm driver requires this to be implemented
     * even though it's optional in the CDC spec, and we don't
     * advertise it in the ACM functional descriptor.
     */
    char local_buf[10];
    struct usb_cdc_notification *notif = (void *)local_buf;

    /* We echo signals back to host as notification. */
    notif->bmRequestType = 0xA1;
    notif->bNotification = USB_CDC_NOTIFY_SERIAL_STATE;
    notif->wValue = 0;
    notif->wIndex = 0;
    notif->wLength = 2;
    local_buf[8] = req->wValue & 3;
    local_buf[9] = 0;
    // usbd_ep_write_packet(0x83, buf, 10);
    return 1;
  }
  case USB_CDC_REQ_SET_LINE_CODING: 
    if(*len < sizeof(struct usb_cdc_line_coding)) {
      return 0;
    }
    return 1;
  }
  return 0;
}

void cdcacm_data_tx(void *buf,size_t len)
{
    usbd_ep_write_packet(usbd_dev, 0x82, buf, len);
}

void cdcacm_data_rx_cb(usbd_device *usbd_dev, uint8_t ep)
{
  (void)ep;
  char buf[64];
  int len = usbd_ep_read_packet(usbd_dev, 0x01, buf, 64);

  if (len) 
    usart2_tx(buf,len);
}