SXSplashHelper.h

//
//  SXHTTPHelper.h
//  sx
//
//  Created by xiangyu on 4/1/14.
//  Copyright (c) 2014 xiangyu. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface SXSplashHelper : NSObject

+(NSURLRequest *)urlRequestFromString:(NSString *)string;

+(void) checkNewSplashImage;
+(UIImage *) splashImage;

@end

SXSplashHelper.m

//
//  SXHTTPHelper.m
//  sx
//
//  Created by xiangyu on 4/1/14.
//  Copyright (c) 2014 xiangyu. All rights reserved.
//

#import "SXSplashHelper.h"

#define kSplashImageURLKey @"splash"
#define kSplashImageRemoteURLKey @"splash-url"


@implementation SXSplashHelper


+(NSURLRequest *)urlRequestFromString:(NSString *)string{
    NSURL *url = [NSURL URLWithString:string];
    return [NSURLRequest requestWithURL:url];
}

/**
 *  检查最新启动图片，如果与已有不同则下载
 */
+(void) checkNewSplashImage{
    
//    [[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:YES];

    
    NSString *url;
    if (IS_IPHONE_5) {
         url = @"";
    }else {
        url = @"";
    }

    __block NSString *imageUrl = nil;
    
    AFHTTPRequestOperationManager *manager = [AFHTTPRequestOperationManager manager];
    [manager GET:url parameters:nil success:^(AFHTTPRequestOperation *operation, id responseObject) {
        DebugLog(@"JSON: %@", responseObject);
        imageUrl = APIRemoteFromPath(responseObject[@"url"]);
        [self downloadImage:imageUrl];
        if (![[[NSUserDefaults  standardUserDefaults] stringForKey:kSplashImageRemoteURLKey] isEqualToString:imageUrl]){
            [self downloadImage:imageUrl];
        }else {
            DebugLog(@"Slpash image not changed!");
        }
    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        DebugLog(@"Error: %@", error);
    }];


}


/**
 *  下载启动图片到 Document/图片名
 *
 *  @param imageUrl  图片HTTP地址
 */
+(void)downloadImage : (NSString *)imageUrl{
    DebugLog(@"Download Image .... %@", imageUrl);
    
    NSURLSessionConfiguration *configuration = [NSURLSessionConfiguration defaultSessionConfiguration];
    AFURLSessionManager *sm = [[AFURLSessionManager alloc] initWithSessionConfiguration:configuration];
    
    NSURL *URL = [NSURL URLWithString:imageUrl];
    NSURLRequest *request = [NSURLRequest requestWithURL:URL];
    
    NSURLSessionDownloadTask *downloadTask = [sm downloadTaskWithRequest:request progress:nil destination:^NSURL *(NSURL *targetPath, NSURLResponse *response) {
        NSURL *documentsDirectoryURL = [[NSFileManager defaultManager] URLForDirectory:NSDocumentDirectory inDomain:NSUserDomainMask appropriateForURL:nil create:NO error:nil];
        
        NSURL *localUrl =  [documentsDirectoryURL URLByAppendingPathComponent:[response suggestedFilename]];
   
        return localUrl;
    } completionHandler:^(NSURLResponse *response, NSURL *filePath, NSError *error) {
        DebugLog(@"File downloaded to: %@", filePath);
        
        [[NSUserDefaults standardUserDefaults] setObject:imageUrl forKey:kSplashImageRemoteURLKey];
        [[NSUserDefaults standardUserDefaults] setURL:filePath forKey:kSplashImageURLKey];
        [[NSUserDefaults standardUserDefaults] synchronize];
        
    }];
    [downloadTask resume];
}




/**
 *  获取启动图片
 *
 *  @return 启动图片UIImage
 */
+(UIImage *) splashImage{
    NSURL *url = [[NSUserDefaults standardUserDefaults] URLForKey:kSplashImageURLKey];
    UIImage *image = [UIImage imageWithData:[NSData dataWithContentsOfURL:url]];
    return image;
}


@end