/*
	libusb test: control TAKARA TOMY's Glitter panel (16x16 LED module)

	references:
	http://penguin.tantin.jp/hard/libusb%E3%81%AB%E3%81%A4%E3%81%84%E3%81%A6.html
	http://www.nc.ie.u-ryukyu.ac.jp/studentlab/index.php?libusb
	http://d.hatena.ne.jp/tch/20091110
	http://www.mail-archive.com/freebsd-users-jp@jp.freebsd.org/msg01708.html

	--- public domain, no warranty.
*/

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
#include <usb.h>	// libusb

extern	uint16_t	Doubler[];
extern	uint8_t		FontData[];

/* display one character */
static	void	display_character(struct usb_dev_handle *dev, unsigned char c, int msec)
{
#define	EP_ADR_IN		0x81
#define	EP_ADR_OUT		0x02

	int	i;
	char	buf[6 + 32 + 8], *b;

	buf[0] = 0x80;
	buf[1] = 0x03;
	buf[2] = 0x5c;	// bit[3:2] brightness (00:25% 01:50% 10:75% 11:100%)
	buf[3] = 0x08;
	buf[4] = 0x00;
	buf[5] = 0x00;

	b = &buf[6];		// start position of data
	for (i = 0; i < 8; i++) {
		*b++ = Doubler[FontData[c * 8 + i]] >> 8;	// left  8px
		*b++ = Doubler[FontData[c * 8 + i]];		// right 8px
		*b++ = Doubler[FontData[c * 8 + i]] >> 8;	// left  8px
		*b++ = Doubler[FontData[c * 8 + i]];		// right 8px
	}

	/* add 1 packet to synch toggle bit */
	// total 6 packets to device (the extra is ignored)
	for (i = 0; i < 8; i++) {
		*b++ = 0x00;
	}
	
	/* send data */
	if (usb_interrupt_write(dev, EP_ADR_OUT, buf, sizeof(buf), 0) < 0) {
		printf("usb_interrupt_write %s\n", usb_strerror());
	}

	/* delay to next character */
	usleep(msec * 1000);

	return;
}

/* action */
static	void	do_action(struct usb_device *dev, char *string, int msec)
{
	int	i;
	usb_dev_handle	*dh;

	/* open device */
	dh = usb_open(dev);
	if (dh == NULL) {
		printf("usb_open NULL\n");
		goto fin0;
	}

	/* set configuration */
	if (usb_set_configuration(dh, dev->config->bConfigurationValue) < 0) {
		printf("usb_set_configuration %s\n", usb_strerror());
		goto fin1;
	}

	/* claim interface */
	if (usb_claim_interface(dh,
		dev->config->interface->altsetting->bInterfaceNumber) < 0) {
		printf("usb_claim_interface %s\n", usb_strerror());
		goto fin1;
	}

	/* send data to USB */
	for (i = 0; i < strlen(string); i++) {
		display_character(dh, string[i], msec);
	}

	/* clear display */
	display_character(dh, ' ', msec);

//fin2:
	usb_release_interface(dh, dev->config->interface->altsetting->bInterfaceNumber);
fin1:
	usb_close(dh);
fin0:
	return;
}

/* test main */
static	void	usb_test(char *string, int msec)
{
#define	VENDOR_ID	0x0f30
#define	PRODUCT_ID	0x0040

	struct	usb_bus	*bus;
	struct	usb_device	*dev;
	int	found, bnum, dnum;

	/* initialize libusb */
	usb_init();
	usb_find_busses();
	usb_find_devices();

	/* no device as default */
	found = 0;

	/* find device */
	for (bus = usb_get_busses(), bnum = 0; bus != NULL;
	     bus = bus->next, bnum++) {

		for (dev = bus->devices, dnum = 0; dev != NULL;
		     dev = dev->next, dnum++) {

			if (dev->descriptor.idVendor == VENDOR_ID &&
			    dev->descriptor.idProduct == PRODUCT_ID) {
				found = 1;
				goto found;
			}
		}
	}

found:
	/* do action when device is found */
	if (found) {
		printf("device at %03d:%03d\n", bnum, dnum);
		do_action(dev, string, msec);
	} else {
		printf("device not found\n");
	}

	return;
}

int	main(int argc, char *argv[])
{
	int	msec;

	if (argc < 3) {
		printf("usage: %s [delay(msec)] [string]\n", argv[0]);
		return 0;
	}

	msec = atoi(argv[1]);
	usb_test(argv[2], msec);
	return 0;
}