#include <stdio.h>
#include <string.h>
#include <usb.h>
#include <errno.h>

/*
 * Temper.c by Robert Kavaler (c) 2009 (relavak.com)
 * All rights reserved.
 *
 * Temper driver for linux. This program can be compiled either as a library
 * or as a standalone program (-DUNIT_TEST). The driver will work with some
 * TEMPer usb devices from RDing (www.PCsensor.com).
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 * 
 * THIS SOFTWARE IS PROVIDED BY Robert Kavaler ''AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL Robert kavaler BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 */

#include "temper.h"

#define VENDOR_ID  0x1130
#define PRODUCT_ID 0x660c

struct Temper {
	struct usb_device *device;
	usb_dev_handle *handle;
	int debug;
	int timeout;
};

	Temper *
TemperCreate(struct usb_device *dev, int timeout, int debug)
{
	Temper *t;
	int ret;

	t = calloc(1, sizeof(*t));
	t->device = dev;
	t->debug = debug;
	t->timeout = timeout;
	t->handle = usb_open(t->device);
	if(!t->handle) {
		free(t);
		return NULL;
	}
	if(t->debug) {
		printf("Trying to detach kernel driver\n");
	}

	ret = usb_detach_kernel_driver_np(t->handle, 0);
	if(ret) {
		if(errno == ENODATA) {
			if(t->debug) {
				printf("Device already detached\n");
			}
		} else {
			if(t->debug) {
				printf("Detach failed: %s[%d]\n",
						strerror(errno), errno);
				printf("Continuing anyway\n");
			}
		}
	} else {
		if(t->debug) {
			printf("detach successful\n");
		}
	}
	ret = usb_detach_kernel_driver_np(t->handle, 1);
	if(ret) {
		if(errno == ENODATA) {
			if(t->debug)
				printf("Device already detached\n");
		} else {
			if(t->debug) {
				printf("Detach failed: %s[%d]\n",
						strerror(errno), errno);
				printf("Continuing anyway\n");
			}
		}
	} else {
		if(t->debug) {
			printf("detach successful\n");
		}
	}

	if(usb_set_configuration(t->handle, 1) < 0 ||
			usb_claim_interface(t->handle, 0) < 0 ||
			usb_claim_interface(t->handle, 1)) {
		usb_close(t->handle);
		free(t);
		return NULL;
	}
	return t;
}

	Temper *
TemperCreateFromDeviceNumber(int deviceNum, int timeout, int debug)
{
	struct usb_bus *bus;
	int n;

	n = 0;
	for(bus=usb_get_busses(); bus; bus=bus->next) {
		struct usb_device *dev;

		for(dev=bus->devices; dev; dev=dev->next) {
			if(debug) {
				printf("Found device: %04x:%04x\n",
						dev->descriptor.idVendor,
						dev->descriptor.idProduct);
			}
			if(dev->descriptor.idVendor == VENDOR_ID &&
					dev->descriptor.idProduct == PRODUCT_ID) {
				if(debug) {
					printf("Found deviceNum %d\n", n);
				}
				if(n == deviceNum) {
					return TemperCreate(dev, timeout, debug);
				}
				n++;
			}
		}
	}
	return NULL;
}

	void
TemperFree(Temper *t)
{
	if(t) {
		if(t->handle) {
			usb_close(t->handle);
		}
		free(t);
	}
}

	static int
TemperSendCommand(Temper *t, int a, int b, int c, int d, int e, int f, int g, int h)
{
	unsigned char buf[32];
	int ret;

	bzero(buf, 32);
	buf[0] = a;
	buf[1] = b;
	buf[2] = c;
	buf[3] = d;
	buf[4] = e;
	buf[5] = f;
	buf[6] = g;
	buf[7] = h;

	if(t->debug) {
		printf("sending bytes %d, %d, %d, %d, %d, %d, %d, %d\n",
				a, b, c, d, e, f, g, h);
	}

	ret = usb_control_msg(t->handle, 0x21, 9, 0x200, 0x01,
			(char *) buf, 32, t->timeout);
	if(ret != 32) {
		perror("usb_control_msg failed");
		return -1;
	}
	return 0;
}

	static int
TemperGetData(Temper *t, char *buf, int len)
{
	int ret;

	return usb_control_msg(t->handle, 0xa1, 1, 0x300, 0x01,
			(char *) buf, len, t->timeout);
}

	int
TemperGetTemperatureInC(Temper *t, float *tempC)
{
	char buf[256];
	int ret, temperature, i;

	TemperSendCommand(t, 10, 11, 12, 13, 0, 0, 2, 0);
	TemperSendCommand(t, 0x54, 0, 0, 0, 0, 0, 0, 0);
	for(i = 0; i < 7; i++) {
		TemperSendCommand(t, 0, 0, 0, 0, 0, 0, 0, 0);
	}
	TemperSendCommand(t, 10, 11, 12, 13, 0, 0, 1, 0);
	ret = TemperGetData(t, buf, 256);
	if(ret < 2) {
		return -1;
	}

	temperature = (buf[1] & 0xFF) + (buf[0] << 8);	
	temperature += 1152;			// calibration value
	*tempC = temperature * (125.0 / 32000.0);
	return 0;
}

	int
TemperGetOtherStuff(Temper *t, char *buf, int length)
{
	TemperSendCommand(t, 10, 11, 12, 13, 0, 0, 2, 0);
	TemperSendCommand(t, 0x52, 0, 0, 0, 0, 0, 0, 0);
	TemperSendCommand(t, 10, 11, 12, 13, 0, 0, 1, 0);
	return TemperGetData(t, buf, length);
}


#define USB_TIMEOUT 1000	/* milliseconds */
#define DEBUG_MODE 1
#define SLEEP_TIMEOUT 10

	int
main(int argv,char** args)
{


	Temper *t;
	char buf[256];
	int i, ret,oneshot=0;
	if (argv == 2 && (args[1][1] == 'h' || args[1][0] == 'h'))
	{
		printf("Temper, does the right thing in C\n");
		printf("recompile with DEBUG_MODE = 1 for all the debug printing\n");
		printf("recompile with SLEEP_TIMEOUT = XX for a different polling interval\n");
		exit(0);
	}

	usb_set_debug(DEBUG_MODE);
	usb_init();
	usb_find_busses();
	usb_find_devices();

	t = TemperCreateFromDeviceNumber(0, USB_TIMEOUT, DEBUG_MODE);
	if(!t) {
		perror("TemperCreate");
		exit(-1);
	}

	/*
	   TemperSendCommand(t, 10, 11, 12, 13, 0, 0, 2, 0);
	   TemperSendCommand(t, 0x43, 0, 0, 0, 0, 0, 0, 0);
	   TemperSendCommand(t, 0, 0, 0, 0, 0, 0, 0, 0);
	   TemperSendCommand(t, 0, 0, 0, 0, 0, 0, 0, 0);
	   TemperSendCommand(t, 0, 0, 0, 0, 0, 0, 0, 0);
	   TemperSendCommand(t, 0, 0, 0, 0, 0, 0, 0, 0);
	   TemperSendCommand(t, 0, 0, 0, 0, 0, 0, 0, 0);
	   TemperSendCommand(t, 0, 0, 0, 0, 0, 0, 0, 0);
	 */

	bzero(buf, 256);
	ret = TemperGetOtherStuff(t, buf, 256);

	float tempc;

	if(TemperGetTemperatureInC(t, &tempc) < 0) {
		perror("TemperGetTemperatureInC");
		exit(1);
	}

	printf("%.2f\n", tempc);
	return 0;
}