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/*
* Copyright (c) 2007 Dave Dribin, Lucas Newman
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#import "DDHidKeyboardBarcodeScanner.h"
#import "DDHidElement.h"
#import "DDHidUsage.h"
#import "DDHidQueue.h"
#import "DDHidEvent.h"
#include <IOKit/hid/IOHIDUsageTables.h>
@interface DDHidKeyboardBarcodeScanner (DDHidKeyboardBarcodeDelegate)
- (void) ddhidKeyboardBarcodeScanner: (DDHidKeyboardBarcodeScanner *) keyboardBarcodeScanner
gotBarcode: (NSString *) barcode;
@end
@interface DDHidKeyboardBarcodeScanner (Private)
- (void) initKeyboardElements: (NSArray *) elements;
- (void) ddhidQueueHasEvents: (DDHidQueue *) hidQueue;
- (void) processBarcodeDigit: (unsigned) usageId;
- (void) clearAccumulatedInput;
- (void) invalidateBarcodeInputTimer;
@end
@implementation DDHidKeyboardBarcodeScanner
+ (NSArray *) allPossibleKeyboardBarcodeScanners;
{
return [DDHidDevice allDevicesMatchingUsagePage: kHIDPage_GenericDesktop
usageId: kHIDUsage_GD_Keyboard
withClass: self
skipZeroLocations: YES];
}
- (id) initWithDevice: (io_object_t) device error: (NSError **) error_;
{
self = [super initWithDevice: device error: error_];
if (self == nil)
return nil;
mKeyElements = [[NSMutableArray alloc] init];
mAccumulatedDigits = [[NSMutableString alloc] init];
mBarcodeInputTimer = nil;
if ([[self productName] rangeOfString:@"Apple"].location != NSNotFound || [[self productName] rangeOfString:@"Internal"].location != NSNotFound)
mIsLikelyKeyboardBarcodeScanner = NO;
else
mIsLikelyKeyboardBarcodeScanner = YES; // if we see invalid barcodes, we can change our mind
[self initKeyboardElements: [self elements]];
return self;
}
//===========================================================
// dealloc
//===========================================================
- (void) dealloc
{
[self invalidateBarcodeInputTimer];
[mKeyElements release];
[mAccumulatedDigits release];
mKeyElements = nil;
mAccumulatedDigits = nil;
[super dealloc];
}
#pragma mark -
#pragma mark Keyboard Elements
- (NSArray *) keyElements;
{
return mKeyElements;
}
- (unsigned) numberOfKeys;
{
return [mKeyElements count];
}
- (void) addElementsToQueue: (DDHidQueue *) queue;
{
[queue addElements: mKeyElements];
}
#pragma mark -
#pragma mark Asynchronous Notification
- (void) setDelegate: (id) delegate;
{
mDelegate = delegate;
}
- (void) addElementsToDefaultQueue;
{
[self addElementsToQueue: mDefaultQueue];
}
#pragma mark -
#pragma mark Properties
- (BOOL) isLikelyKeyboardBarcodeScanner;
{
return mIsLikelyKeyboardBarcodeScanner;
}
@end
@implementation DDHidKeyboardBarcodeScanner (DDHidKeyboardDelegate)
- (void) ddhidKeyboardBarcodeScanner: (DDHidKeyboardBarcodeScanner *) keyboardBarcodeScanner
gotBarcode: (NSString *) barcode;
{
if ([mDelegate respondsToSelector: _cmd])
[mDelegate ddhidKeyboardBarcodeScanner: keyboardBarcodeScanner gotBarcode: barcode];
}
@end
@implementation DDHidKeyboardBarcodeScanner (Private)
- (void) initKeyboardElements: (NSArray *) elements;
{
NSEnumerator * e = [elements objectEnumerator];
DDHidElement * element;
while ((element = [e nextObject]))
{
unsigned usagePage = [[element usage] usagePage];
unsigned usageId = [[element usage] usageId];
if (usagePage == kHIDPage_KeyboardOrKeypad)
{
if ((usageId >= kHIDUsage_KeyboardA) && (usageId <= kHIDUsage_Keyboard0))
{
[mKeyElements addObject: element];
}
}
NSArray * subElements = [element elements];
if (subElements != nil)
[self initKeyboardElements: subElements];
}
}
- (void) ddhidQueueHasEvents: (DDHidQueue *) hidQueue;
{
DDHidEvent * event;
while ((event = [hidQueue nextEvent]))
{
DDHidElement * element = [self elementForCookie: [event elementCookie]];
unsigned usageId = [[element usage] usageId];
SInt32 value = [event value];
if (value == 1) // key down
[self processBarcodeDigit: usageId];
}
}
#define UPC_A_BARCODE_LENGTH (12)
#define BARCODE_INPUT_TIMEOUT (0.5)
- (void) processBarcodeDigit: (unsigned) usageId;
{
if (usageId <= kHIDUsage_KeyboardZ || usageId >= kHIDUsage_KeyboardCapsLock) { // an alphabetic key was pressed => probably not a barcode scanner
[self willChangeValueForKey:@"isLikelyKeyboardBarcodeScanner"];
mIsLikelyKeyboardBarcodeScanner = NO;
[self didChangeValueForKey:@"isLikelyKeyboardBarcodeScanner"];
[self clearAccumulatedInput];
return;
}
if (!mBarcodeInputTimer) // schedule a timer to make sure we get the rest of the digits in a timely manner
mBarcodeInputTimer = [[NSTimer scheduledTimerWithTimeInterval:BARCODE_INPUT_TIMEOUT target:self selector:@selector(fireBarcodeInputTimeout:) userInfo:nil repeats:NO] retain];
[mAccumulatedDigits appendString:[NSString stringWithFormat:@"%d", (usageId + 1) % 10]];
}
- (void) fireBarcodeInputTimeout: (NSTimer *) timer;
{
if ([mAccumulatedDigits length] >= UPC_A_BARCODE_LENGTH)
[self ddhidKeyboardBarcodeScanner: self gotBarcode: [[mAccumulatedDigits copy] autorelease]];
[self clearAccumulatedInput];
}
- (void) clearAccumulatedInput;
{
[mAccumulatedDigits deleteCharactersInRange:NSMakeRange(0, [mAccumulatedDigits length])];
[self invalidateBarcodeInputTimer];
}
- (void) invalidateBarcodeInputTimer;
{
[mBarcodeInputTimer invalidate];
[mBarcodeInputTimer release];
mBarcodeInputTimer = nil;
}
@end
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