#define F_CPU 12000000L

#include <avr/io.h>
#include <avr/delay.h>
#include <avr/wdt.h>
#include <avr/interrupt.h>
#include "usbdrv/usbdrv.h"

PROGMEM const char usbHidReportDescriptor[52] = { /* USB report descriptor, size must match usbconfig.h */
    0x05, 0x01,                    // USAGE_PAGE (Generic Desktop)
    0x09, 0x02,                    // USAGE (Mouse)
    0xa1, 0x01,                    // COLLECTION (Application)
    0x09, 0x01,                    //   USAGE (Pointer)
    0xA1, 0x00,                    //   COLLECTION (Physical)
    0x05, 0x09,                    //     USAGE_PAGE (Button)
    0x19, 0x01,                    //     USAGE_MINIMUM
    0x29, 0x03,                    //     USAGE_MAXIMUM
    0x15, 0x00,                    //     LOGICAL_MINIMUM (0)
    0x25, 0x01,                    //     LOGICAL_MAXIMUM (1)
    0x95, 0x03,                    //     REPORT_COUNT (3)
    0x75, 0x01,                    //     REPORT_SIZE (1)
    0x81, 0x02,                    //     INPUT (Data,Var,Abs)
    0x95, 0x01,                    //     REPORT_COUNT (1)
    0x75, 0x05,                    //     REPORT_SIZE (5)
    0x81, 0x03,                    //     INPUT (Const,Var,Abs)
    0x05, 0x01,                    //     USAGE_PAGE (Generic Desktop)
    0x09, 0x30,                    //     USAGE (X)
    0x09, 0x31,                    //     USAGE (Y)
    0x09, 0x38,                    //     USAGE (Wheel)
    0x15, 0x81,                    //     LOGICAL_MINIMUM (-127)
    0x25, 0x7F,                    //     LOGICAL_MAXIMUM (127)
    0x75, 0x08,                    //     REPORT_SIZE (8)
    0x95, 0x03,                    //     REPORT_COUNT (3)
    0x81, 0x06,                    //     INPUT (Data,Var,Rel)
    0xC0,                          //   END_COLLECTION
    0xC0,                          // END COLLECTION
};

/* This is the same report descriptor as seen in a Logitech mouse. The data
 * described by this descriptor consists of 4 bytes:
 *      .  .  .  .  . B2 B1 B0 .... one byte with mouse button states
 *     X7 X6 X5 X4 X3 X2 X1 X0 .... 8 bit signed relative coordinate x
 *     Y7 Y6 Y5 Y4 Y3 Y2 Y1 Y0 .... 8 bit signed relative coordinate y
 *     W7 W6 W5 W4 W3 W2 W1 W0 .... 8 bit signed relative coordinate wheel
 */
typedef struct{
    uchar   buttonMask;
    char    dx;
    char    dy;
    char    dWheel;
} report_t;


report_t reportBuffer;


/* device is detected, however unreliably. dunno why. */


void debug(int i)
{
	if (i >= 63) i=63;
	PORTB = ~i;
}

USB_PUBLIC uchar usbFunctionSetup(uchar data[8])
{
	usbRequest_t* rq = (usbRequest_t*) data;

    if ((rq->bmRequestType & USBRQ_TYPE_MASK) == USBRQ_TYPE_CLASS  &&
        (rq->bRequest == USBRQ_HID_GET_REPORT))
    {  
    	debug(32);
            // wValue: ReportType (highbyte), ReportID (lowbyte)
            usbMsgPtr = (void *)&reportBuffer; // we only have this one
            return sizeof(reportBuffer);
    }

	return 0;
}


int main (void)
{
	char rand=123;

	DDRC=0x00;
	PORTC=0x00;

	DDRB=0xFF;

	wdt_enable(WDTO_1S);

	usbInit();

	usbDeviceDisconnect();
	for (int i=0;i<100;i++)
	{
		PORTB=~i;
		wdt_reset();
		_delay_ms(5);
	}
	usbDeviceConnect();

	PORTB=~42;

	sei();
debug(4);
	while(1)
	{
		wdt_reset();
		usbPoll();
		
		if(usbInterruptIsReady()) { // if the interrupt is ready, feed data
		    // pseudo-random sequence generator, thanks to Dan Frederiksen @AVRfreaks
		    // http://en.wikipedia.org/wiki/Linear_congruential_generator
		    rand=(rand*109+89)%251;
		    
		    // move to a random direction
		    reportBuffer.dx = (rand&0xf)-8; 
		    reportBuffer.dy = ((rand&0xf0)>>4)-8;

		    usbSetInterrupt((void *)&reportBuffer, sizeof(reportBuffer));

		    debug(2);
		}
	}

	return 0; // never reached
}