/* This souce code written by Michael Rolig (email: michael_rolig@alumni.macalester.edu)
 * This can be considered to be in the public domain
 *
 * modified for hidapi, by nishio@hh.iij4u.or.jp.
 * This code is still considered to be in the public domain
 *
 * cc -g radioshark.c -lhidapi-libusb -std=c99
 */

#define __RCSID(_s)	__asm(".section rcsid\n\t.asciz \"" _s "\"\n\t.previous")
__RCSID("$Id: radioshark.c,v 1.6 2017/09/21 15:57:58 nishio Exp $");
#define SHARK_VENDID 0x077d	/* Griffin's Vendor ID */
#define SHARK_DEVID  0x627a	/* The radioSHARK's Device ID */

#define SEND_PACKET_LENGTH 6	/* size of an instruction packet */
#define MAX_STR 255

#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <hidapi/hidapi.h>

int debug = 0;
void
usage(int argc, const char **argv)
{
	printf("%s [opts] [freq]\n\tchange state of radioSHARK\n\n", argv[0]);
	printf("opts:\n"
	       " -blue <intensity>  : turn on blue LED (0-127) '-blue 127'\n"
	       " -blink <freqency>  : turn on blue LED pulsing (0-127) '-blink 64'\n"
	       " -red <0/1>         : turn on/off red LED '-red 1'\n"
	       "freq:\n"
	       " AM ---  522 - 1710\n"
	       " FM --- 76.0 - 108.0(effective range is 85.0 - 108.0)\n"
	       " ignore tailing garbage\n");
}
int
write_packet(hid_device *handle, unsigned char packet[], int size)
{
	int ret;
	ret = hid_write(handle, packet, size);
	if (ret < 0 || debug) {
		fprintf(stderr, "%s:\t", ret < 0 ? "Cannot set" : "write");
		for (int i = 0; i < size; i++) {
			fprintf(stderr, "%2.2x%c", packet[i], i == size - 1 ? '\n' : ' ');
		}
	}
	return ret;
}

struct node {
	unsigned char *p;
	struct node *next;
};

struct node *
new_node()
{
	struct node *p = malloc(sizeof (struct node));
	p->next = NULL;
	p->p = malloc(SEND_PACKET_LENGTH);
	if (p == NULL || p->p == NULL) {
		perror("Cannot allocate new node\n");
		exit(1);
	}
	memset(p->p, 0, SEND_PACKET_LENGTH);
	return p;
}

int
main(int argc, const char **argv)
{
	struct node root = { NULL, NULL};
	struct node *cur_node = &root;
	/* Declare variables used later */
	int ret;
	hid_device *handle;

	for (const char **p = argv + 1; *p; p++) {
		char buf[BUFSIZ];
		unsigned char *PACKET;
		if (strcmp(*p, "-d") == 0) {
			debug++;
			continue;
		}
		struct node *node = new_node();
		unsigned char *packet = node->p;
		if (strcmp(*p, "-blue") == 0 || strcmp(*p, "-blink") == 0) {
			int val = -1;
			packet[0] = (*p)[3] == 'u' ? 0xa0 : 0xa1;
			p++;
			if (*p && isdigit(**p)) {
				val = atoi(*p);
			}
			sprintf(buf, "%d", val);
			if (val < 0 || 127 < val || strcmp(buf, *p) != 0) {
				fprintf(stderr, "%s: %s %s... 0-127\n", argv[0], *(p - 1), *p);
				exit(2);
			}
			packet[1] = val;
		} else if (strcmp(*p, "-red") == 0) {
			++p;
			if (*p && strcmp(*p, "0") == 0) {
				packet[0] = 0xA8;
			} else if (*p && strcmp(*p, "1") == 0) {
				packet[0] = 0xA9;
			} else {
				fprintf(stderr, "%s %s %s ... 0 or 1\n", argv[0], *(p - 1), *p);
				exit(2);
			}
		} else if (strcmp(*p, "-h") == 0) {
			usage(argc, argv);
			exit(0);
		} else if (*p && isdigit(**p)) {
			char *hz = NULL;
			double freq = 0.0;
			unsigned short efreq = 0;
			freq = atof(*p);
			packet[0] = 0xC0;
			if (522.0 <= freq && freq <= 1710.0) {
				efreq = (unsigned short)freq + 450;
				packet[1] = 0x12;
				hz = "kHz";
			} else if (76.0 <= freq && freq <= 108.0) {
				efreq = ((freq * 1000) + 10700) / 12.5;
				efreq += 3;
				packet[1] = 0x02; // 0?
				hz = "MHz";
			} else {
				fprintf(stderr, "%s: %s is band.\n", argv[0], *p);
				exit(2);
			}
			packet[2] = (efreq >> 8) & 0xFF;
			packet[3] =  efreq & 0xFF;
			if (debug) {
				fprintf(stderr, "freq:\t%5g %s\t0x%4.4x\n", freq, hz, efreq);
			}
		} else {
			fprintf(stderr, "%s: unknown param(%s)\n\n", argv[0], *p);
			exit(2);
		}
		cur_node->next = node;
		cur_node = cur_node->next;
	}
	if (ret = hid_init()) {
		fprintf(stderr, "Cannot init hid lib\n");
		exit(1);
	}

	if ((handle = hid_open(SHARK_VENDID, SHARK_DEVID, NULL)) == NULL) {
		fprintf(stderr, "Cannot open: device %4.4x:%x\n", SHARK_VENDID, SHARK_DEVID);
		exit(1);
	}
	if (debug) {
		wchar_t wstr[MAX_STR];
		ret = hid_get_manufacturer_string(handle, wstr, MAX_STR);
		wprintf(L"mfr:\t%ls\n", wstr);
		ret = hid_get_product_string(handle, wstr, MAX_STR);
		wprintf(L"prod:\t%ls\n", wstr);
	}
	for (struct node *cur = root.next; cur; cur = cur->next) {
		if (!*cur->p)
			continue;
		if (write_packet(handle, cur->p, SEND_PACKET_LENGTH) < 0) {
			exit(1);
		}
	}
	hid_close(handle);
	exit(hid_exit());
}

/*
  Retrieved from "http://wiki.linuxquestions.org/wiki/RadioSHARKSource"
*/