util.js

// Utility functions


// Namespace
Abcd = {};


// Game context handling
var app;
Abcd.context = {
	database: "",
	home: null,
	object: null,
	screen: "",
	lang: "fr",
	casevalue: 0,
	screenContext: null
};
Abcd.saveContext = function() {
  document.getElementById("stop-button").addEventListener('click', function (event) {
    var values = [];
    values.push(Abcd.context.object!=null?Abcd.context.object.kindName:"");
    values.push(Abcd.context.lang);
    values.push(Abcd.context.casevalue);
    values.push(Abcd.context.object!=null?Abcd.context.object.saveContext():"");
    var datastoreObject = Abcd.activity.getDatastoreObject();
    var jsonData = JSON.stringify({context:values.join("#"), database:Abcd.context.getDatabase()});
    datastoreObject.setDataAsText(jsonData);
    datastoreObject.save(function() {});
  });
};
Abcd.loadContext = function(callback) {
	var datastoreObject = Abcd.activity.getDatastoreObject();
	datastoreObject.loadAsText(function (error, metadata, data) {
		var context = JSON.parse(data);
		if (context) {
			var values = context.context.split('#');
			Abcd.context.screen = values[0];
			Abcd.context.lang = values[1];
			Abcd.context.casevalue = values[2];
			Abcd.context.screenContext = values[3];
			Abcd.setLocale(Abcd.context.lang);
			callback();
		}
	});
};


// Init Sugar interface
Abcd.setLocale = function(lang) {
	var texts = Abcd.getTextsFromLocal(lang);
    __$FC_l10n_set(texts);
	Abcd.letters = Abcd[lang+"Letters"];
	if (Abcd.context.object != null)
		Abcd.context.object.setLocale();
}

Abcd.getTextsFromLocal = function(lang) {
    switch (lang) {
    case "fr":
        return Abcd.frTexts;
    case "es":
        return Abcd.esTexts;
    default:
        return Abcd.enTexts;
    }
}

Abcd.getLettersFromLocal = function(lang) {
    switch (lang) {
    case "fr":
        return Abcd.frLetters;
    case "es":
        return Abcd.esLetters;
    default:
        return Abcd.enLetters;
    }
}

Abcd.setCase = function(casevalue) {
	Abcd.context.casevalue = casevalue;
	if (Abcd.context.object != null)
		Abcd.context.object.setCase();
}
Abcd.log = function(msg) {
	console.log(msg);
};


// Home handling
Abcd.goHome = function() {
if (Abcd.context.home != null) {
  if (Abcd.context.object == null)
    return;
  Abcd.context.screen = "";
  Abcd.context.object = null;
  Abcd.context.home.renderInto(document.getElementById("body"));
  Abcd.context.home.playTheme();
}
};

//Buttons to show and hide Language and Case Button\
var x = document.getElementsByClassName("switchCase");
var y = document.getElementsByClassName("switchLang");

Abcd.hideCase =	function() {
	var i;
	for (i = 0; i < x.length; i++) {
		x[i].style.visibility = "hidden";
	}
}
		
Abcd.showCase = function() {
  	var i;
  	for (i = 0; i < x.length; i++) {
  		x[i].style.visibility = "visible";
  	}
 }
Abcd.hideLang =	function() {
	var i;
	for (i = 0; i < y.length; i++) {
		y[i].style.visibility = "hidden";
	}
}
		
Abcd.showLang = function() {
  	var i;
  	for (i = 0; i < y.length; i++) {
  		y[i].style.visibility = "visible";
  	}
}

//--- Utilities

// Change visibility of a set of controls
Abcd.changeVisibility = function(object, items) {
	for(var item in items) {
		if (items[item])
			object.$[item].show();
		else
			object.$[item].hide();
	}
}

// Randomly get an entry in the current language
Abcd.randomEntryIndex = function(excludes, filter) {
	// Get first level
	var value = null;
	if (filter != null && filter.kind == "Abcd.Collection") {
		// Get the collection
		var collection = Abcd.collections[filter.index];
		var length = collection.entries.length;
		value = [];
		for (var i = 0 ; i < length ; i++) {
			var entry = collection.entries[i];
			if (Abcd.entries[entry][Abcd.context.lang] == 1)
				value.push(entry);
		}
	} else {
		// Choose a letter
		var firstlen = 0;
		var firstindex = -1;
		for(var key in Abcd.letters) {
			if (filter != null && filter.letter == key) {
				firstindex = firstlen;
				break;
			}
			if (Abcd.letters.hasOwnProperty(key)) firstlen++;
		}
		if (firstindex == -1)
			firstindex = Math.floor(Math.random()*firstlen);

		// Choose an index
		var i = 0;
		for(var key in Abcd.letters) {
			if (i++ == firstindex) {
				value = Abcd.letters[key];
				break;
			}
		}
	}

	// Copy without excludes
	var array = [];
	for (var i = 0 ; i < value.length ; i++) {
		var found = false;
		if (excludes !== undefined) {
			for (var j = 0 ; !found && j < excludes.length ; j++) {
				if (value[i] == excludes[j])
					found = true;
			}
		}
		if (!found)
			array.push(value[i]);
	}

	// Select one randomely
	var secondlen = array.length;
	var secondindex = Math.floor(Math.random()*secondlen);
	return array[secondindex];
}

// Mix an array into a new one
Abcd.mix = function(chain) {
	// Check size
	if (chain.length < 2) {
		return chain;
	}

	// Mix cards
	var mixedchain = [];
	var tomix = enyo.cloneArray(chain);
	while (tomix.length != 1) {
		// Take a card
		var i = Math.floor(Math.random()*tomix.length);
		mixedchain.push(tomix[i]);
		tomix[i] = null;

		// Remix
		var newmix = [];
		for (var j = 0 ; j < tomix.length ; j++) {
			if (tomix[j] != null)
				newmix.push(tomix[j]);
		}
		tomix = newmix;
	}
	mixedchain.push(tomix[0]);

	return mixedchain;
};

// Encoding functions taken from
// https://developer.mozilla.org/en-US/docs/Web/API/WindowBase64/Base64_encoding_and_decoding
function uint6ToB64 (nUint6) {
	return nUint6 < 26 ?
		nUint6 + 65 : nUint6 < 52 ?
		nUint6 + 71 : nUint6 < 62 ?
		nUint6 - 4 : nUint6 === 62 ?
		43 : nUint6 === 63 ?
		47 : 65;
}
Abcd.toBase64 = function(aBytes) {
	var eqLen = (3 - (aBytes.length % 3)) % 3, sB64Enc = "";
	for (var nMod3, nLen = aBytes.length, nUint24 = 0, nIdx = 0; nIdx < nLen; nIdx++) {
		nMod3 = nIdx % 3;
		nUint24 |= aBytes[nIdx] << (16 >>> nMod3 & 24);
		if (nMod3 === 2 || aBytes.length - nIdx === 1) {
			sB64Enc += String.fromCharCode(uint6ToB64(nUint24 >>> 18 & 63), uint6ToB64(nUint24 >>> 12 & 63), uint6ToB64(nUint24 >>> 6 & 63), uint6ToB64(nUint24 & 63));
			nUint24 = 0;
		}
	}
	return  eqLen === 0 ? sB64Enc : sB64Enc.substring(0, sB64Enc.length - eqLen) + (eqLen === 1 ? "=" : "==");
}