#import "ViewController.h"
@interface ViewController ()<NSURLSessionDownloadDelegate>
@end
@implementation ViewController
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
  [self delegate];
}

-(void)delegate
{
  //1.url
  NSURL *url = [NSURL URLWithString:@"http://120.25.226.186:32812/resources/images/minion_03.png"];
  
  //2.創(chuàng)建請求對象
  NSURLRequest *request = [NSURLRequest requestWithURL:url];
  
  //3.創(chuàng)建session ：注意代理為NSURLSessionDownloadDelegate
  NSURLSession *session = [NSURLSession sessionWithConfiguration:[NSURLSessionConfiguration defaultSessionConfiguration] delegate:self delegateQueue:[NSOperationQueue mainQueue]];
  
  //4.創(chuàng)建Task
  NSURLSessionDownloadTask *downloadTask = [session downloadTaskWithRequest:request];
  
  //5.執(zhí)行Task
  [downloadTask resume];
}

#pragma mark ----------------------
#pragma mark NSURLSessionDownloadDelegate
/**
 * 寫數(shù)據(jù)
 *
 * @param session          會話對象
 * @param downloadTask       下載任務(wù)
 * @param bytesWritten       本次寫入的數(shù)據(jù)大小
 * @param totalBytesWritten     下載的數(shù)據(jù)總大小
 * @param totalBytesExpectedToWrite 文件的總大小
 */
-(void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didWriteData:(int64_t)bytesWritten totalBytesWritten:(int64_t)totalBytesWritten totalBytesExpectedToWrite:(int64_t)totalBytesExpectedToWrite
{
  //1. 獲得文件的下載進度
  NSLog(@"%f",1.0 * totalBytesWritten/totalBytesExpectedToWrite);
}

/**
 * 當恢復(fù)下載的時候調(diào)用該方法
 *
 * @param fileOffset     從什么地方下載
 * @param expectedTotalBytes 文件的總大小
 */
-(void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didResumeAtOffset:(int64_t)fileOffset expectedTotalBytes:(int64_t)expectedTotalBytes
{
  NSLog(@"%s",__func__);
}

/**
 * 當下載完成的時候調(diào)用
 *
 * @param location   文件的臨時存儲路徑
 */
-(void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didFinishDownloadingToURL:(NSURL *)location
{
  NSLog(@"%@",location);
  
  //1 拼接文件全路徑
  NSString *fullPath = [[NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject] stringByAppendingPathComponent:downloadTask.response.suggestedFilename];
  
  //2 剪切文件
  [[NSFileManager defaultManager]moveItemAtURL:location toURL:[NSURL fileURLWithPath:fullPath] error:nil];
  NSLog(@"%@",fullPath);
}

/**
 * 請求結(jié)束
 */
-(void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error
{
  NSLog(@"didCompleteWithError");
}
@end