#import "WebViewJavascriptBridge.h"

#ifdef USE_JSONKIT

#import "JSONKit.h"

#endif

@interface WebViewJavascriptBridge ()

@property (nonatomic,strong) NSMutableArray *startupMessageQueue;

@property (nonatomic,strong) NSMutableDictionary *responseCallbacks;

@property (nonatomic,strong) NSMutableDictionary *messageHandlers;

@property (atomic,assign) NSInteger uniqueId;

@property (nonatomic, strong) UIWebView* webView;

@property (nonatomic, strong) id <UIWebViewDelegate> webViewDelegate;

@property (nonatomic, copy) WVJBHandler messageHandler;

- (void)_flushMessageQueue;

- (void)_sendData:(NSDictionary*)data responseCallback:(WVJBResponseCallback)responseCallback handlerName:(NSString*)handlerName;

- (void)_queueMessage:(NSDictionary*)message;

- (void)_dispatchMessage:(NSDictionary*)message;

@end

@implementation WebViewJavascriptBridge

static NSString *MESSAGE_SEPARATOR = @"__WVJB_MESSAGE_SEPERATOR__";

static NSString *CUSTOM_PROTOCOL_SCHEME = @"wvjbscheme";

static NSString *QUEUE_HAS_MESSAGE = @"__WVJB_QUEUE_MESSAGE__";

+ (id)javascriptBridgeForWebView:(UIWebView *)webView handler:(WVJBHandler)handler {

return [self javascriptBridgeForWebView:webView webViewDelegate:nil handler:handler];

}

+ (id)javascriptBridgeForWebView:(UIWebView *)webView webViewDelegate:(id<UIWebViewDelegate>)webViewDelegate handler:(WVJBHandler)messageHandler {

WebViewJavascriptBridge* bridge = [[WebViewJavascriptBridge alloc] init];

bridge.messageHandler = messageHandler;

bridge.startupMessageQueue = [NSMutableArray array];

bridge.responseCallbacks = [NSMutableDictionary dictionary];

bridge.messageHandlers = [NSMutableDictionary dictionary];

bridge.uniqueId = 0;

bridge.webView = webView;

bridge.webViewDelegate = webViewDelegate;

webView.delegate = bridge;

return bridge;

}

- (void)send:(NSDictionary *)data {

[self send:data responseCallback:nil];

}

- (void)send:(NSDictionary *)data responseCallback:(WVJBResponseCallback)responseCallback {

[self _sendData:data responseCallback:responseCallback handlerName:nil];

}

- (void)callHandler:(NSString *)handlerName {

[self callHandler:handlerName data:nil responseCallback:nil];

}

- (void)callHandler:(NSString *)handlerName data:(id)data {

[self callHandler:handlerName data:data responseCallback:nil];

}

- (void)callHandler:(NSString *)handlerName data:(id)data responseCallback:(WVJBResponseCallback)responseCallback {

[self _sendData:data responseCallback:responseCallback handlerName:handlerName];

}

- (void)registerHandler:(NSString *)handlerName handler:(WVJBHandler)handler {

[self.messageHandlers setObject:handler forKey:handlerName];

}

- (void)_sendData:(NSDictionary *)data responseCallback:(WVJBResponseCallback)responseCallback handlerName:(NSString*)handlerName {

NSMutableDictionary* message = [NSMutableDictionary dictionaryWithObject:data forKey:@"data"];

if (responseCallback) {

NSString* callbackId = [NSString stringWithFormat:@"objc_cb_%d", ++_uniqueId];

[self.responseCallbacks setObject:responseCallback forKey:callbackId];

[message setObject:callbackId forKey:@"callbackId"];

}

if (handlerName) {

[message setObject:handlerName forKey:@"handlerName"];

}

[self _queueMessage:message];

}

- (void)_queueMessage:(NSDictionary *)message {

if (self.startupMessageQueue) {

[self.startupMessageQueue addObject:message];

} else {

[self _dispatchMessage:message];

}

}

- (void)_dispatchMessage:(NSDictionary *)message {

#ifdef USE_JSONKIT

NSString *messageJSON = [message JSONString];

#else

NSString *messageJSON = [[NSString alloc] initWithData:[NSJSONSerialization dataWithJSONObject:message options:0 error:nil] encoding:NSUTF8StringEncoding];

#endif

messageJSON = [messageJSON stringByReplacingOccurrencesOfString:@"\\" withString:@"\\\\"];

messageJSON = [messageJSON stringByReplacingOccurrencesOfString:@"\"" withString:@"\\\""];

messageJSON = [messageJSON stringByReplacingOccurrencesOfString:@"\'" withString:@"\\\'"];

messageJSON = [messageJSON stringByReplacingOccurrencesOfString:@"\n" withString:@"\\n"];

messageJSON = [messageJSON stringByReplacingOccurrencesOfString:@"\r" withString:@"\\r"];

messageJSON = [messageJSON stringByReplacingOccurrencesOfString:@"\f" withString:@"\\f"];

[_webView stringByEvaluatingJavaScriptFromString:[NSString stringWithFormat:@"WebViewJavascriptBridge._handleMessageFromObjC('%@');", messageJSON]];

}

- (void)_flushMessageQueue {

NSString *messageQueueString = [_webView stringByEvaluatingJavaScriptFromString:@"WebViewJavascriptBridge._fetchQueue();"];

NSArray* messages = [messageQueueString componentsSeparatedByString:MESSAGE_SEPARATOR];

for (NSString *messageJSON in messages) {

// normal message - pass to bridge

#ifdef USE_JSONKIT

NSDictionary *message = [messageJSON objectFromJSONString];

#else

NSDictionary *message = [NSJSONSerialization JSONObjectWithData:[messageJSON dataUsingEncoding:NSUTF8StringEncoding] options:0 error:nil];

#endif

WVJBResponseCallback responseCallback = NULL;

if ([message objectForKey:@"callbackId"]) {

__block NSString* responseId = [message objectForKey:@"callbackId"];

responseCallback = ^(NSDictionary* data) {

NSDictionary* responseMessage = [NSDictionary dictionaryWithObjectsAndKeys: responseId, @"responseId", data, @"data", nil];

[self _queueMessage:responseMessage];

};

}

WVJBHandler handler = self.messageHandler;

if ([message objectForKey:@"handlerName"]) {

handler = [self.messageHandlers objectForKey:[message objectForKey:@"handlerName"]];

} else if ([message objectForKey:@"responseId"]) {

handler = [self.responseCallbacks objectForKey:[message objectForKey:@"responseId"]];

}

@try {

handler([message objectForKey:@"data"], responseCallback);

}

@catch (NSException *exception) {

NSLog(@"WebViewJavascriptBridge: WARNING: handler threw. %@ %@", message, exception);

}

}

}

#pragma mark UIWebViewDelegate

- (void)webViewDidFinishLoad:(UIWebView *)webView {

if (webView != _webView) { return; }

if (![[_webView stringByEvaluatingJavaScriptFromString:@"typeof WebViewJavascriptBridge == 'object'"] isEqualToString:@"true"]) {

NSString *filePath = [[NSBundle mainBundle] pathForResource:@"WebViewJavascriptBridge.js" ofType:@"txt"];

NSString *js = [NSString stringWithContentsOfFile:filePath encoding:NSUTF8StringEncoding error:nil];

[_webView stringByEvaluatingJavaScriptFromString:js];

}

if (self.startupMessageQueue) {

for (id queuedMessage in self.startupMessageQueue) {

[self _dispatchMessage:queuedMessage];

}

self.startupMessageQueue = nil;

}

if (self.webViewDelegate) {

[self.webViewDelegate webViewDidFinishLoad:webView];

}

}

- (void)webView:(UIWebView *)webView didFailLoadWithError:(NSError *)error {

if (webView != _webView) { return; }

if (self.webViewDelegate) {

[self.webViewDelegate webView:_webView didFailLoadWithError:error];

}

}

- (BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType {

if (webView != _webView) { return YES; }

NSURL *url = [request URL];

if ([[url scheme] isEqualToString:CUSTOM_PROTOCOL_SCHEME]) {

if ([[url host] isEqualToString:QUEUE_HAS_MESSAGE]) {

[self _flushMessageQueue];

} else {

NSLog(@"WebViewJavascriptBridge: WARNING: Received unknown WebViewJavascriptBridge command %@://%@", CUSTOM_PROTOCOL_SCHEME, [url path]);

}

return NO;

} else if (self.webViewDelegate) {

return [self.webViewDelegate webView:webView shouldStartLoadWithRequest:request navigationType:navigationType];

} else {

return YES;

}

}

- (void)webViewDidStartLoad:(UIWebView *)webView {

if (webView != _webView) { return; }

if (self.webViewDelegate) {

[self.webViewDelegate webViewDidStartLoad:webView];

}

}

@end