/*
 * =====================================================================================
 *
 *       Filename:  hanvon-libusb.c
 *
 *    Description:  Libusb GP0504 handler prototype
 *
 *        Version:  0.1 
 *        Created:  08/17/2020 04:05:14 PM
 *       Revision:  none
 *       Compiler:  gcc
 *
 *         Author:  surkeh@protonmail.com
 *
 * =====================================================================================
 */

#include <stdlib.h>
#include <stdio.h>
#include <libusb-1.0/libusb.h>

#define STATE_SUCCESS 0
#define STATE_NOT_FOUND 1

#define UNREF_DEVICE 1 
#define KEEP_DEVICE_REF 0 

#define VENDOR_ID_HANVON	0x0b57
#define PRODUCT_ID_AM3M		0x8528
#define PRODUCT_ID_AM0806	0x8502
#define PRODUCT_ID_AM0605	0x8503
#define PRODUCT_ID_AM1107	0x8505
#define PRODUCT_ID_AM1209	0x8501
#define PRODUCT_ID_RL0604	0x851f
#define PRODUCT_ID_RL0504	0x851d
#define PRODUCT_ID_GP0806	0x8039
#define PRODUCT_ID_GP0806B	0x8511
#define PRODUCT_ID_GP0605	0x8512
#define PRODUCT_ID_GP0605A	0x803a
#define PRODUCT_ID_GP0504	0x8037
#define PRODUCT_ID_NXS1513	0x8030
#define PRODUCT_ID_GP0906	0x8521
#define PRODUCT_ID_APPIV0906	0x8532

#define AM_PACKET_LEN   10

//static int lbuttons[]={BTN_0,BTN_1,BTN_2,BTN_3};   /* reported on all AMs */
//static int rbuttons[]={BTN_4,BTN_5,BTN_6,BTN_7};   /* reported on AM1107+ */

#define AM_WHEEL_THRESHOLD   4

#define AM_MAX_TILT_X   0x3f
#define AM_MAX_TILT_Y   0x7f
#define AM_MAX_PRESSURE   0x400



struct hanvon {
	unsigned char *data;
	//dma_addr_t data_dma;
	struct input_dev *dev;
	struct usb_device *usbdev;
	struct urb *irq;
	int old_wheel_pos;
	char phys[32];
};

void callback(struct libusb_transfer *transfer) {
  int i = 0;
  for(; i < 10; i++) {
    printf("%c, ", transfer -> buffer[i]);
  }
  printf("placeholder\n");
}

int find_device(libusb_device **list, unsigned int count) {
	if (count < 0) {
		return -1;
	}
	int found = -1;
	struct libusb_device_descriptor desc;
	for (unsigned int i = 0; i < count; i++) {
		libusb_device *t = list[i];
		libusb_get_device_descriptor(list[i], &desc);

		printf( "Dev%u ID %04x:%04x\n", (i), desc.idVendor, desc.idProduct );

		if (desc.idVendor == VENDOR_ID_HANVON) {
			switch(desc.idProduct) {		
				default:
					break;
				case PRODUCT_ID_AM0806:
				case PRODUCT_ID_AM0605:
				case PRODUCT_ID_AM1107:
				case PRODUCT_ID_AM1209:
				case PRODUCT_ID_RL0604:
				case PRODUCT_ID_RL0504:
				case PRODUCT_ID_GP0806:
				case PRODUCT_ID_GP0806B:
				case PRODUCT_ID_GP0605:
				case PRODUCT_ID_GP0605A:
				case PRODUCT_ID_GP0504:
				case PRODUCT_ID_NXS1513:
				case PRODUCT_ID_GP0906:
				case PRODUCT_ID_APPIV0906:
					return i;
			} // end switch
		} // end if
	} // end for 
 	return found;
}



libusb_device *FindHanvon( libusb_context **context);
int HandleData( void );


int main()
{
#define UNREF_DEVICE 1 
#define KEEP_DEVICE_REF 0 

    libusb_device ** devs;
    int r = libusb_init(NULL);
    if (r < 0) {
        return r;
    } 
    int count = libusb_get_device_list(NULL, &devs);
    if (count < 0) {
        libusb_exit(NULL);
        return count;
    }

	int index = find_device(devs, count);
	if (index < 0) {
		printf("Device not plugged in\n");
		return 0;
	}

	printf("Device #%i\n", index);

	libusb_device_handle *h;
	int state = libusb_open(devs[index], &h);
	libusb_free_device_list (devs, UNREF_DEVICE);

	if (state < 0 || h == NULL) {
		printf(" Something happened, %i.\n", state);
		return 0;	
	}

	printf("Got to this point\n");


	// Wait and handle interrupts?
	struct libusb_transfer tx;

	const int ENDPOINT_ADDR = 0x81; // bEndpointAddress from lsusb -v
	const unsigned int LEN = 10;    // wMaxPacketSize from lsusb -v
	unsigned char buffer[LEN];
	// assign timeout of 1s, for any action is too much as is
	libusb_fill_interrupt_transfer(	&tx, 
					h, 
					ENDPOINT_ADDR, 
					buffer, 
					LEN,
					callback,
					NULL, 
					130); // milliseconds

	state = libusb_submit_transfer(&tx);
	if (state < 0 ) {
		return state;
	}
    for(;;) {
        libusb_handle_events(NULL);
    }
    return state;
}



libusb_device *FindHanvon( libusb_context **context)
{
    libusb_device **deviceList;
    libusb_device *found = NULL;
    ssize_t nDevices = libusb_get_device_list( context[0], &deviceList);
    if( nDevices > 0 )
      {
        struct libusb_device_descriptor description;

        for( ssize_t i = 0; i < nDevices; i++ )
        {
          libusb_device *device = deviceList[i]; 
          libusb_get_device_descriptor(device, &description);
          printf( "Dev%u ID %04x:%04x\n", (i + 1), description.idVendor, description.idProduct );
          if( description.idVendor ==  VENDOR_ID_HANVON )
          {
            switch( description.idProduct )
            case PRODUCT_ID_AM0806:
            case PRODUCT_ID_AM0605:
            case PRODUCT_ID_AM1107:
            case PRODUCT_ID_AM1209:
            case PRODUCT_ID_RL0604:
            case PRODUCT_ID_RL0504:
            case PRODUCT_ID_GP0806:
            case PRODUCT_ID_GP0806B:
            case PRODUCT_ID_GP0605:
            case PRODUCT_ID_GP0605A:
            case PRODUCT_ID_GP0504:
            case PRODUCT_ID_NXS1513:
            case PRODUCT_ID_GP0906:
            case PRODUCT_ID_APPIV0906:
              found = device;
              break;
          }
        }
        printf( "\n\n" );
      }

    libusb_free_device_list( deviceList, UNREF_DEVICE );
    return found;
}