#import <sys/utsname.h>

typedef NS_ENUM(NSUInteger, AADeviceModel) {
    AADeviceModelUnknown,
    AADeviceModeliPhone4S,
    AADeviceModeliPodTouch5 = AADeviceModeliPhone4S,
    AADeviceModeliPad2 = AADeviceModeliPhone4S,
    AADeviceModeliPadMini = AADeviceModeliPad2,
    AADeviceModeliPad3,
    AADeviceModeliPhone5,
    AADeviceModeliPhone5c = AADeviceModeliPhone5,
    AADeviceModeliPad4,
    AADeviceModeliPhone5s,
    AADeviceModeliPadAir = AADeviceModeliPhone5s,
    AADeviceModeliPadMini2 = AADeviceModeliPadAir,
    AADeviceModeliPadMini3 = AADeviceModeliPadMini2,
    AADeviceModeliPhone6,
    AADeviceModeliPhone6Plus = AADeviceModeliPhone6,
    AADeviceModeliPadMini4 = AADeviceModeliPhone6,
    AADeviceModeliPadAir2,
    AADeviceModeliPhone6s,
    AADeviceModeliPhone6sPlus = AADeviceModeliPhone6,
    AADeviceModeliPadPro,
}

- (AADeviceModel)currentDeviceModel
{
    NSError *error = nil;
    NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"(iPod|iPhone|iPad)(\\d+),\\d+"
                                                                           options:0
                                                                             error:&error];

    if (error) {
        return AADeviceModelUnknown;
    }

    struct utsname systemInfo;
    uname(&systemInfo);

    NSString *deviceName = [NSString stringWithCString:systemInfo.machine
                                              encoding:NSUTF8StringEncoding];

    NSArray<NSTextCheckingResult *> *matches = [regex matchesInString:deviceName
                                                              options:NSMatchingProgress
                                                                range:NSMakeRange(0, deviceName.length)];

    for (NSTextCheckingResult *match in matches) {
        if (match.numberOfRanges < 3) {
            continue;
        }

        NSRange deviceTypeRange = [match rangeAtIndex:1];
        NSString *deviceType = [deviceName substringWithRange:deviceTypeRange];

        NSRange deviceGenRange = [match rangeAtIndex:2];
        NSInteger deviceGeneration = [[deviceName substringWithRange:deviceGenRange] integerValue];

        if ([deviceType isEqualToString:@"iPod"]) {
            if (deviceGeneration <= 5) {
                return AADeviceModeliPodTouch5;
            }
            return AADeviceModeliPodTouch6;
        } else if ([deviceType isEqualToString:@"iPhone"]) {
            if (deviceGeneration <= 4) {
                return AADeviceModeliPhone4S;
            } else if (deviceGeneration == 5) {
                return AADeviceModeliPhone5;
            } else if (deviceGeneration == 6) {
                return AADeviceModeliPhone6;
            }
            return AADeviceModeliPhone6s;
        } else if ([deviceType isEqualToString:@"iPad"]) {
            if (deviceGeneration <= 2) {
                return AADeviceModeliPad2;
            } else if (deviceGeneration == 3) {
                return AADeviceModeliPad3;
            } else if (deviceGeneration == 4) {
                return AADeviceModeliPad4;
            } else if (deviceGeneration == 5) {
                return AADeviceModeliPadAir;
            } else if (deviceGeneration == 6) {
                return AADeviceModeliPadAir2;
            }
            return AADeviceModeliPadPro;
        }
    }

    return AADeviceModelUnknown;
}