erpsuiteios/Redant Drivers/Apex And Drivers/UIImage+RedAnt.m

//
//  UIImage+RedAnt.m
//  Apex And Drivers
//
//  Created by Jack on 2018/8/29.
//  Copyright © 2018年 USAI. All rights reserved.
//

#import "UIImage+RedAnt.h"
#import <CommonCrypto/CommonCrypto.h>

static dispatch_semaphore_t _lock;

#define Lock() dispatch_semaphore_wait(_lock, DISPATCH_TIME_FOREVER)
#define Unlock() dispatch_semaphore_signal(_lock)

@implementation UIImage (RedAnt)

+ (void)load {
    _lock = dispatch_semaphore_create(1);
}

+ (instancetype)ra_imageWithURL:(NSURL *)url {
    
    if (url == nil) {
        return nil;
    }
    
    if ([url.scheme isEqualToString:@"file"]) {
        return [UIImage imageWithContentsOfFile:url.absoluteString];
    }
    
    NSString *md5 = [self md5:url.absoluteString];
    
    NSString *imgDir = [self imageCacheDir];
    NSString *imgPath = [imgDir stringByAppendingPathComponent:md5];
    
    NSFileManager *fileManager = [NSFileManager defaultManager];
    
    BOOL isDir = NO;
    BOOL exist = [fileManager fileExistsAtPath:imgPath isDirectory:&isDir];
    
    if (exist && !isDir) {
        return [UIImage imageWithContentsOfFile:imgPath];
    } else {
        
        NSData *imgData = [NSData dataWithContentsOfURL:url];
        
        exist = [fileManager fileExistsAtPath:imgDir isDirectory:&isDir];
        if ((exist && isDir) || !exist) {
            [fileManager createDirectoryAtPath:imgDir withIntermediateDirectories:YES attributes:nil error:nil];
        }
        
        if (imgData) {
            Lock();
            [imgData writeToFile:imgPath atomically:NO];
            Unlock();
            
            return [UIImage imageWithData:imgData];
        } else {
            return nil;
        }
    }
}

+ (NSString *)imageCacheDir {
    return [[NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingPathComponent:@"ra_image"];
}

+ (nullable NSString *)md5:(nullable NSString *)str {
    if (!str) return nil;
    
    const char *cStr = str.UTF8String;
    unsigned char result[CC_MD5_DIGEST_LENGTH];
    CC_MD5(cStr, (CC_LONG)strlen(cStr), result);
    
    NSMutableString *md5Str = [NSMutableString string];
    for (int i = 0; i < CC_MD5_DIGEST_LENGTH; ++i) {
        [md5Str appendFormat:@"%02x", result[i]];
    }
    return md5Str;
}

@end