exec.js

/*
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 *
*/

/**
 * Creates the exec bridge used to notify the native code of
 * commands.
 */
var cordova = require('cordova');
var utils = require('cordova/utils');
var base64 = require('cordova/base64');

function massageArgsJsToNative (args) {
    if (!args || utils.typeName(args) !== 'Array') {
        return args;
    }
    var ret = [];
    args.forEach(function (arg, i) {
        if (utils.typeName(arg) === 'ArrayBuffer') {
            ret.push({
                CDVType: 'ArrayBuffer',
                data: base64.fromArrayBuffer(arg)
            });
        } else {
            ret.push(arg);
        }
    });
    return ret;
}

function massageMessageNativeToJs (message) {
    if (message.CDVType === 'ArrayBuffer') {
        var stringToArrayBuffer = function (str) {
            var ret = new Uint8Array(str.length);
            for (var i = 0; i < str.length; i++) {
                ret[i] = str.charCodeAt(i);
            }
            return ret.buffer;
        };
        var base64ToArrayBuffer = function (b64) {
            return stringToArrayBuffer(atob(b64)); // eslint-disable-line no-undef
        };
        message = base64ToArrayBuffer(message.data);
    }
    return message;
}

function convertMessageToArgsNativeToJs (message) {
    var args = [];
    if (!message || !Object.prototype.hasOwnProperty.call(message, 'CDVType')) {
        args.push(message);
    } else if (message.CDVType === 'MultiPart') {
        message.messages.forEach(function (e) {
            args.push(massageMessageNativeToJs(e));
        });
    } else {
        args.push(massageMessageNativeToJs(message));
    }
    return args;
}

var iOSExec = function () {
    var successCallback, failCallback, service, action, actionArgs;
    var callbackId = null;
    if (typeof arguments[0] !== 'string') {
        // FORMAT ONE
        successCallback = arguments[0];
        failCallback = arguments[1];
        service = arguments[2];
        action = arguments[3];
        actionArgs = arguments[4];

        // Since we need to maintain backwards compatibility, we have to pass
        // an invalid callbackId even if no callback was provided since plugins
        // will be expecting it. The Cordova.exec() implementation allocates
        // an invalid callbackId and passes it even if no callbacks were given.
        callbackId = 'INVALID';
    } else {
   	    throw new Error('The old format of this exec call has been removed (deprecated since 2.1). Change to: ' + // eslint-disable-line
            'cordova.exec(null, null, \'Service\', \'action\', [ arg1, arg2 ]);');
    }

    // If actionArgs is not provided, default to an empty array
    actionArgs = actionArgs || [];

    // Register the callbacks and add the callbackId to the positional
    // arguments if given.
    if (successCallback || failCallback) {
        callbackId = service + cordova.callbackId++;
        cordova.callbacks[callbackId] =
            { success: successCallback, fail: failCallback };
    }

    actionArgs = massageArgsJsToNative(actionArgs);

    // CB-10133 DataClone DOM Exception 25 guard (fast function remover)
    var command = [callbackId, service, action, JSON.parse(JSON.stringify(actionArgs))];
    window.webkit.messageHandlers.cordova.postMessage(command);
};

iOSExec.nativeCallback = function (callbackId, status, message, keepCallback, debug) {
    var success = status === 0 || status === 1;
    var args = convertMessageToArgsNativeToJs(message);
    Promise.resolve().then(function () {
        cordova.callbackFromNative(callbackId, success, status, args, keepCallback); // eslint-disable-line
    });
};

// for backwards compatibility
iOSExec.nativeEvalAndFetch = function (func) {
    try {
        func();
    } catch (e) {
        console.log(e);
    }
};

// Proxy the exec for bridge changes. See CB-10106

function cordovaExec () {
    var cexec = require('cordova/exec');
    var cexec_valid = (typeof cexec.nativeFetchMessages === 'function') && (typeof cexec.nativeEvalAndFetch === 'function') && (typeof cexec.nativeCallback === 'function');
    return (cexec_valid && execProxy !== cexec) ? cexec : iOSExec;
}

function execProxy () {
    cordovaExec().apply(null, arguments);
}

execProxy.nativeFetchMessages = function () {
    return cordovaExec().nativeFetchMessages.apply(null, arguments);
};

execProxy.nativeEvalAndFetch = function () {
    return cordovaExec().nativeEvalAndFetch.apply(null, arguments);
};

execProxy.nativeCallback = function () {
    return cordovaExec().nativeCallback.apply(null, arguments);
};

module.exports = execProxy;