/*
 * Copyright (c) 2014 Petroules Corporation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 THE COPYRIGHT OWNER OR CONTRIBUTORS 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.
 */

#import "NSProcessInfo+PECocoaBackports.h"

#if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
#import <UIKit/UIKit.h>
#elif defined(TARGET_OS_MAC) && TARGET_OS_MAC
#import <CoreServices/CoreServices.h>
#endif

@interface NSProcessInfo (PECocoaBackportsPrivate)

#if LOAD_OPERATING_SYSTEM_VERSION
- (NSOperatingSystemVersion)PECocoaBackports_operatingSystemVersion;
- (BOOL)PECocoaBackports_isOperatingSystemAtLeastVersion:(NSOperatingSystemVersion)version;
#endif

@end

@implementation NSProcessInfo (PECocoaBackportsPrivate)

+ (void)load
{
#if LOAD_OPERATING_SYSTEM_VERSION
    // Public API since OS X 10.10 (present since 10.9) and iOS 8.0
    class_addInstanceMethodIfNecessary([self class],
                                       NSSelectorFromString(@"operatingSystemVersion"),
                                       @selector(PECocoaBackports_operatingSystemVersion));
    
    // Public API since OS X 10.10 (present since 10.9) and iOS 8.0
    class_addInstanceMethodIfNecessary([self class],
                                       NSSelectorFromString(@"isOperatingSystemAtLeastVersion:"),
                                       @selector(PECocoaBackports_isOperatingSystemAtLeastVersion:));
#endif
}

#if LOAD_OPERATING_SYSTEM_VERSION
- (NSOperatingSystemVersion)PECocoaBackports_operatingSystemVersion
{
    NSOperatingSystemVersion v = {0, 0, 0};
    SInt32 major = 0, minor = 0, patch = 0;
#if defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE
#if !defined(__has_feature) || !__has_feature(objc_arc)
    NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
#endif
    NSArray *parts = [[[UIDevice currentDevice] systemVersion] componentsSeparatedByString:@"."];
    major = parts.count > 0 ? [[parts objectAtIndex:0] intValue] : 0;
    minor = parts.count > 1 ? [[parts objectAtIndex:1] intValue] : 0;
    patch = parts.count > 2 ? [[parts objectAtIndex:2] intValue] : 0;
#if !defined(__has_feature) || !__has_feature(objc_arc)
    [pool release];
#endif
#elif defined(TARGET_OS_MAC) && TARGET_OS_MAC
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-declarations"
    if (Gestalt(gestaltSystemVersionMajor, &major) != noErr) return v;
    if (Gestalt(gestaltSystemVersionMinor, &minor) != noErr) return v;
    if (Gestalt(gestaltSystemVersionBugFix, &patch) != noErr) return v;
#pragma clang diagnostic pop
#endif
    v.majorVersion = major;
    v.minorVersion = minor;
    v.patchVersion = patch;
    return v;
}

- (BOOL)PECocoaBackports_isOperatingSystemAtLeastVersion:(NSOperatingSystemVersion)version
{
    const NSOperatingSystemVersion systemVersion = [self operatingSystemVersion];
    if (systemVersion.majorVersion == version.majorVersion) {
        if (systemVersion.minorVersion == version.minorVersion) {
            return systemVersion.patchVersion >= version.patchVersion;
        }
        return systemVersion.minorVersion >= version.minorVersion;
    }
    return systemVersion.majorVersion >= version.majorVersion;
}
#endif

@end