#include <iron_net.h>
#import <Foundation/Foundation.h>
#import <objc/runtime.h>

volatile uint64_t iron_net_bytes_downloaded = 0;
static NSURLSession *download_session = nil;

@interface IronDownloadDelegate : NSObject <NSURLSessionDownloadDelegate>
@end

@implementation IronDownloadDelegate

- (void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didWriteData:(int64_t)bytesWritten totalBytesWritten:(int64_t)totalBytesWritten totalBytesExpectedToWrite:(int64_t)totalBytesExpectedToWrite {
	iron_net_bytes_downloaded += bytesWritten;
}

- (void)URLSession:(NSURLSession *)session downloadTask:(NSURLSessionDownloadTask *)downloadTask didFinishDownloadingToURL:(NSURL *)location {
	NSString *dstPath = objc_getAssociatedObject(downloadTask, @"dst_path");
	if (dstPath) {
		NSError *error = nil;
		NSURL *destURL = [NSURL fileURLWithPath:dstPath];
		[[NSFileManager defaultManager] moveItemAtURL:location toURL:destURL error:&error];
		// todo
		if ([dstPath hasSuffix:@"sd_vulkan"] || [dstPath hasSuffix:@"sd_cpu"]) {
			NSDictionary *attrs = @{ NSFilePosixPermissions : @0755 };
			NSError *chmodError = nil;
			[[NSFileManager defaultManager] setAttributes:attrs ofItemAtPath:dstPath error:&chmodError];
		}
	}
	else {
		NSData *fileData = [NSData dataWithContentsOfURL:location options:NSDataReadingMappedIfSafe error:nil];
		NSMutableData *memoryData = objc_getAssociatedObject(downloadTask, @"memoryData");
		[memoryData appendData:fileData];
	}
}

- (void)URLSession:(NSURLSession *)session task:(NSURLSessionTask *)task didCompleteWithError:(NSError *)error {
	NSURLSessionDownloadTask *downloadTask = (NSURLSessionDownloadTask *)task;
	NSValue *cbVal = objc_getAssociatedObject(task, @"callback");
	NSValue *dataVal = objc_getAssociatedObject(task, @"callbackdata");
	NSString *dstPath = objc_getAssociatedObject(task, @"dst_path");
	NSMutableData *memoryData = objc_getAssociatedObject(task, @"memoryData");
	iron_https_callback_t callback = cbVal ? [cbVal pointerValue] : NULL;
	void *callbackdata = dataVal ? [dataVal pointerValue] : NULL;
	dispatch_async(dispatch_get_main_queue(), ^{
		if (dstPath) {
			callback(NULL, callbackdata);
		}
		else {
			char *buffer = malloc(memoryData.length + 1);
			memcpy(buffer, memoryData.bytes, memoryData.length);
			buffer[memoryData.length] = '\0';
			callback(buffer, callbackdata);
		}
	});
}

@end

void iron_net_request(const char *url_base, const char *url_path, const char *data, int port, int method, iron_https_callback_t callback, void *callbackdata, const char *dst_path) {
	if (!download_session) {
		NSURLSessionConfiguration *config = [NSURLSessionConfiguration defaultSessionConfiguration];
		NSOperationQueue *queue = [[NSOperationQueue alloc] init];
		queue.qualityOfService = NSQualityOfServiceUtility;

		static IronDownloadDelegate *delegate = nil;
		static dispatch_once_t onceToken;
		dispatch_once(&onceToken, ^{
			delegate = [[IronDownloadDelegate alloc] init];
		});
		download_session = [NSURLSession sessionWithConfiguration:config delegate:delegate delegateQueue:queue];
	}

	NSString *urlStr = [NSString stringWithFormat:@"https://%@:%d/%@",
						[NSString stringWithUTF8String:url_base],
						port,
						[NSString stringWithUTF8String:url_path]];
	NSURL *url = [NSURL URLWithString:urlStr];
	NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
	request.HTTPMethod = (method == IRON_HTTPS_GET) ? @"GET" : @"POST";

	NSURLSessionDownloadTask *task = [download_session downloadTaskWithRequest:request];
	objc_setAssociatedObject(task, @"callback", [NSValue valueWithPointer:callback], OBJC_ASSOCIATION_RETAIN_NONATOMIC);
	objc_setAssociatedObject(task, @"callbackdata", [NSValue valueWithPointer:callbackdata], OBJC_ASSOCIATION_RETAIN_NONATOMIC);
	objc_setAssociatedObject(task, @"dst_path", dst_path ? [NSString stringWithUTF8String:dst_path] : nil, OBJC_ASSOCIATION_COPY_NONATOMIC);
	if (!dst_path) {
		objc_setAssociatedObject(task, @"memoryData", [NSMutableData data], OBJC_ASSOCIATION_RETAIN_NONATOMIC);
	}
	[task resume];
}

void iron_net_update() {
}