// This file contains the source for the Javascript side of the

// WebViewJavascriptBridge. It is plaintext, but converted to an NSString

// via some preprocessor tricks.

//

// Previous implementations of WebViewJavascriptBridge loaded the javascript source

// from a resource. This worked fine for app developers, but library developers who

// included the bridge into their library, awkwardly had to ask consumers of their

// library to include the resource, violating their encapsulation. By including the

// Javascript as a string resource, the encapsulation of the library is maintained.

#import "WebViewJavascriptBridge_JS.h"

NSString * WebViewJavascriptBridge_js() {

#define __wvjb_js_func__(x) #x

// BEGIN preprocessorJSCode

static NSString * preprocessorJSCode = @__wvjb_js_func__(

;(function() {

if (window.WebViewJavascriptBridge) {

return;

}

window.WebViewJavascriptBridge = {

registerHandler: registerHandler,

callHandler: callHandler,

_fetchQueue: _fetchQueue,

_handleMessageFromObjC: _handleMessageFromObjC

};

var messagingIframe;

var sendMessageQueue = [];

var messageHandlers = {};

var CUSTOM_PROTOCOL_SCHEME = 'wvjbscheme';

var QUEUE_HAS_MESSAGE = '__WVJB_QUEUE_MESSAGE__';

var responseCallbacks = {};

var uniqueId = 1;

function registerHandler(handlerName, handler) {

messageHandlers[handlerName] = handler;

}

function callHandler(handlerName, data, responseCallback) {

if (arguments.length == 2 && typeof data == 'function') {

responseCallback = data;

data = null;

}

_doSend({ handlerName:handlerName, data:data }, responseCallback);

}

function _doSend(message, responseCallback) {

if (responseCallback) {

var callbackId = 'cb_'+(uniqueId++)+'_'+new Date().getTime();

responseCallbacks[callbackId] = responseCallback;

message['callbackId'] = callbackId;

}

sendMessageQueue.push(message);

messagingIframe.src = CUSTOM_PROTOCOL_SCHEME + '://' + QUEUE_HAS_MESSAGE;

}

function _fetchQueue() {

var messageQueueString = JSON.stringify(sendMessageQueue);

sendMessageQueue = [];

return messageQueueString;

}

function _dispatchMessageFromObjC(messageJSON) {

setTimeout(function _timeoutDispatchMessageFromObjC() {

var message = JSON.parse(messageJSON);

var messageHandler;

var responseCallback;

if (message.responseId) {

responseCallback = responseCallbacks[message.responseId];

if (!responseCallback) {

return;

}

responseCallback(message.responseData);

delete responseCallbacks[message.responseId];

} else {

if (message.callbackId) {

var callbackResponseId = message.callbackId;

responseCallback = function(responseData) {

_doSend({ responseId:callbackResponseId, responseData:responseData });

};

}

var handler = messageHandlers[message.handlerName];

try {

handler(message.data, responseCallback);

} catch(exception) {

console.log("WebViewJavascriptBridge: WARNING: javascript handler threw.", message, exception);

}

if (!handler) {

console.log("WebViewJavascriptBridge: WARNING: no handler for message from ObjC:", message);

}

}

});

}

function _handleMessageFromObjC(messageJSON) {

_dispatchMessageFromObjC(messageJSON);

}

messagingIframe = document.createElement('iframe');

messagingIframe.style.display = 'none';

messagingIframe.src = CUSTOM_PROTOCOL_SCHEME + '://' + QUEUE_HAS_MESSAGE;

document.documentElement.appendChild(messagingIframe);

setTimeout(_callWVJBCallbacks, 0);

function _callWVJBCallbacks() {

var callbacks = window.WVJBCallbacks;

delete window.WVJBCallbacks;

for (var i=0; i<callbacks.length; i++) {

callbacks[i](WebViewJavascriptBridge);

}

}

})();

); // END preprocessorJSCode

#undef __wvjb_js_func__

return preprocessorJSCode;

};