/*
* File autoLoader for javascript Libraries (multi-scripts).
* copyright @ 2015 - Juan José Guerra Haba <dinertron@gmail.com>
* License: Free. GPL.v3
*
* 'rsLIB' o RSLIB is an acronym for 'require async library' and a scripts library autoloader. It loads Scripts (js, json, ...) and
* even style sheets (CSS). Returns a 'rsLIB' object with a 'onComplete (..)' event to pass a callback function. You only need to use
* it if you do use a resource immediately (variable, method, object ...) from library.
* An options object embedded within the label 'script' call to this charger is expected with the terms:
* - NameLIB: name of the library to load
* - PathToLIB: path (relative or absolute) to the library directory with respect to html caller.
* - Scripts: An array with the path relative to each script file you want to load. The last element of the array will not be
* charged, which is only indicates the main on which to launch the 'onComplete (..)' method.
* The call in the HTML Head might be:
* <script id="rsLIB_ID" class="rsLIB_CLASS" type="text/javascript" src="./scripts/rsLIB.js">
* {
* nameLIB: "PolyArea",
* pathToLIB: "./scripts/PolyArea/",
* scripts: ["./scripts/PolyArea/PolyArea.js",
* "./scripts/PolyArea/css/polyArea.css",
* "./scripts/PolyArea/PolyArea.js"] //The latter will not be charged, only determines the event 'onComplete (..)'
* }
* </script>
* OOP Filosofy and Closures, ECMASCRIPT-6 features such as "use-strict"
* IMPROVEMENTS: Although it uses internally 'eval' in a controlled manner on these updates will be studied how to replace 'eval'
* to 'JSON.parse' or 'JSON.stringify'
*/
/** ASYNC REQUIRE LIBRARY :: INSERT THE LINKED-SCRIPTS PARAMETERS IN THE HEAD SYNCHRONOUSLY, BUT WITHOUT AJAX.
* It create a loader object (global 'rsLIB' variable ) with an anonymous loader function and as members:
* - Options: the complete object detected as embedded options.
* - LIB name: name of the library to load.
* - PathToLIB: the path to the library, based on the situation of HTML caller.
* - Scripts: the array of scripts to load the library.
* - Get: get properties of embedded object.
* - Isset: utility method to check whether a variable is undefined.
* - OnComplete (..): The method that can be passed a callback 'function as the only parameter.
* Import dynamically (albeit unorthodox) the all library 'assets' , it inserting (if not previously existed) after
* the label linked with this file (rsLIB.js) in the 'head'. It work synchronously, that is, they must wait until
* they are loaded and interpreted to use them immediately.
* If so required (immediately) because some variable or function defined in scripts is used, * should work within
* the event 'onComplete ()' through a function callback ', for example:
* rsLIB.onComplete( function(){
* //code to execute when the scripts are loaded.
* } );
*/
var rsLIB = (function(){
"use-strict";
//Configurable static variables (SEMI-CONSTANT). It affects to elements IDs and classes, and labels DOM scripts
var RSLIB_NAME = "rsLIB";
var RSLIB_FILE = RSLIB_NAME + ".js";
var RSLIB_ID = RSLIB_NAME + "_ID";
var RSLIB_CLASS = RSLIB_NAME + "_CLASS";
//variables and methods inner private
/** An options object embedded within the label 'script' call to this charger is expected with the terms:
* - NameLIB: name of the library to load
* - PathToLIB: path (relative or absolute) to the library directory with respect to html caller.
* - Scripts: An array with the path relative to each script file you want to load. The last element of the array will not be
* charged, which is only indicates the main on which to launch the 'onComplete (..)' method. */
var _options = eval("("+RSLIB_getThisScript().innerHTML+")"); //ATENCIÓN: DEBE SER UN OBJETO O NO SURTIRÁ EFECTO
//var _options = JSON.parse((RSLIB_getThisScript().innerHTML));//JSON.stringify
/** External function in the 'onComplete' event to host the code that need immediacy and well make sure the scripts are loaded. */
var _callback=null;
/** It is the couple of callback, depending on the state of the callback is _ready or do not. This is achieved with no gap between
* the charging phase of script and execution callback. */
var _ready=false;
/** Event employee for pass an external callback function to be executed upon completion of the loaded library.
* This can be useful if, for example, you want to immediately use a resource (variable, object, method, ...)
* defined in the library. This should be done within the 'callback' function as incorporating the various scripts
* in Head of a synchronous load page 'modifies the flow execution javascript ' occurs due to the DOM modification,
* it can (depending on the browser) run the last library scripts. */
function RSLIB_onComplete(callback){
/* ... Include here the event or use externally as a callback() function; ... */
_callback = callback;
if(_ready){ _callback(); }
}
/** Public utility function to check if there is a variable, if it has been defined. You must pass the 'typeof' of the
* Variable, not the variable itself. For example: alert (RSLIB.requireIsset (typeof unknown_variable)); */
function RSLIB_isset(typeOfvar){ return (typeOfvar.toUpperCase() !== "UNDEFINED"); }
/** Utility function to get object properties of embedded options. */
function RSLIB_get(prop, defaultValue){
return (_options && _options[prop]) ? _options[prop] : defaultValue;
}
/** Internal utility function to take as NODE object, this script file; */
function RSLIB_getThisScript(){
//DETECT THIS FILE (rsLIB.js) AS A SCRIPT-NODE LINKED IN THE HEAD
//FIRST THINGS LOOK FOR YOUR ID
var requireScript=document.getElementById(RSLIB_ID);
if(requireScript){ return requireScript; }
//IF NOT FOUND, LOOK FOR HIS CLASS
var requireHead = (document.head || document.documentElement || document.getElementsByTagName("head")[0] || document.querySelector("head"));
var requireScripts = requireHead.getElementsByTagName("script");
var requireScript;
for(var i=0; i<requireScripts.length; i++){
if( requireScripts[i].className === RSLIB_CLASS ){
requireScript=requireScripts[i];
break;
}
}
if(requireScript){ return requireScript; }
//IF NOT FOUND, LOOKING FOR HIS FILE NAME
for(var i=0; i<requireScripts.length; i++){
if( requireScripts[i].src.indexOf(RSLIB_FILE) > -1 ){
requireScript=requireScripts[i];
break;
}
}
return requireScript;
}
//DYNAMIC LOAD FOR HEAD-HTML SCRIPTS. THE DETECTED OPTIONS IN SCRIPT-NODE CALLER FOR THIS FILE
(function RSLIB_loadSyncScripts (options){
//IT CHECKS BASIC OPTIONS AND IT ASSIGNS DEFAULT PROPERTY (IF NOT FOUND)
options["scripts"]=RSLIB_get("scripts", []);
options["nameLIB"]=RSLIB_get("nameLIB", "");
options["pathToLIB"]=RSLIB_get("pathToLIB", "./");
//THE LAST ELEMENT DOES NOT LOAD, BUT IT DEFINED IN 'onComplete()' EVENT.
var _scriptCompleted = options.scripts.pop();
options.scripts = options.scripts.reverse(); //THE LAST SHALL BE FIRST IN THE KINGDOM OF GOD
//FOR EACH SCRIPT
for(var i=0; i<options.scripts.length; i++){
if(!options.scripts[i]) { continue; }
var tipo= options.scripts[i].split(".").pop();
var nombreExt= (options.scripts[i].indexOf("\\")>-1) ? options.scripts[i].split("\\").pop() : options.scripts[i].split("/").pop();
nombreExt = nombreExt.replace("\\", "-").replace("/", "-");
//BUILD SCRIPT
var nodoScript;
switch(tipo.toLowerCase()){
case "css":
nodoScript = document.createElement("link");
nodoScript.setAttribute("type", "text/css"); //setAttribute("type", "text/css");
nodoScript.setAttribute("rel", "stylesheet");
nodoScript.setAttribute("media", "screen");
nodoScript.setAttribute("href", options.scripts[i]);
break;
case "js": default: //also "json"
nodoScript = document.createElement("script");
nodoScript.setAttribute("type", "text/javascript");
nodoScript.setAttribute("src", options.scripts[i]);
}
nodoScript.setAttribute("id", nombreExt);
nodoScript.setAttribute("class", RSLIB_NAME + "_" + options.nameLIB);
if(options.scripts[i] === _scriptCompleted){
if (nodoScript.readyState) { // IE
nodoScript.onreadystatechange = function () {
if (nodoScript.readyState === 'loaded' || nodoScript.readyState === 'complete') {
nodoScript.onreadystatechange = null;
if(_callback){
_callback(); //onComplete();
} else {
_ready=true;
}
}
};
} else { // Others
nodoScript.onload = function() {
if(_callback){
_callback(); //onComplete();
} else {
_ready=true;
}
};
}
}
//THIS FILE IS DETECTED (zLIB.js) AS A SCRIPT-NODE LINKED IN SECTION HTML-HEAD
var requireHead = (document.head || document.documentElement || document.getElementsByTagName("head")[0] || document.querySelector("head"));
var requireScripts = requireHead.getElementsByTagName("script");
var requireScript;
var insertar = true;
for(var j=0; j<requireScripts.length; j++){
if(requireScripts[j].src === options.scripts[i]) {
insertar = false;
break;
}
if( (requireScripts[j].id === RSLIB_ID) || (requireScripts[j].className === RSLIB_CLASS) || (requireScripts[j].src.indexOf(RSLIB_FILE) > -1) ){
requireScript=requireScripts[j];
//break;
}
}
//IT IS INSERTED (if not previously existed) AFTER THIS LINKED FILE (rsLIB.js) IN THE SECTION HTML-HEAD
if(insertar) { requireHead.insertBefore(nodoScript, requireScript.nextSibling); }
}
//IS REPOSITIONED AS THEY WERE
options.scripts = options.scripts.reverse();
//IT MAKES TRAILS DELETED FOR ALL CONFIGURATION OPTIONS
RSLIB_getThisScript().innerHTML="";
})(_options);
//PUBLIC API
return {
/** It is an options object embedded within the label 'script' call to this charger is expected with the terms:
* - NameLIB: name of the library to load
* - PathToLIB: path (relative or absolute) to the library directory with respect to html caller.
* - Scripts: An array with the path relative to each script file you want to load. The last element of the array will not be
* charged, which is only indicates the main on which to launch the 'onComplete (..)' method. */
options: _options,
/** Name of the library to load */
nameLIB: RSLIB_get("nameLIB", ""),
/** Path to the library directory with respect to html caller. */
pathToLIB: RSLIB_get("pathToLIB", "./"),
/** Scripts to dynamic load for the loader function. They should contain the relative path.
* WARNING: THE LAST ELEMENT NOT BE CHARGED, WHICH IS ONLY INDICATES THE MAIN ON WHICH TO LAUNCH THE 'onComplete(..)' EVENT. */
scripts: RSLIB_get("scripts", []),
/** Utility function to get a property of embedded options object. */
get: RSLIB_get,
/** Public utility function to check if there is a variable, if it has been defined. You must pass the 'typeof' of the
* Variable, not the variable itself. For example: alert (RSLIB.requireIsset (typeof unknown_variable)); */
isset : RSLIB_isset,
/** Event employee for pass an external callback function to be executed upon completion of the loaded library.
* This can be useful if, for example, you want to immediately use a resource (variable, object, method, ...)
* defined in the library. This should be done within the 'callback' function as incorporating the various scripts
* in Head of a synchronous load page 'modifies the flow execution javascript ' occurs due to the DOM modification,
* it can (depending on the browser) run the last library scripts. */
onComplete: RSLIB_onComplete
}
})();
//document.normalize();
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