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// Make sure the utilities module is loaded (will only load if not already)
mw.loader.using( 'mediawiki.util', function () {

    // Wait for the page to be parsed
    $( document ).ready( function () { 

        var link = mw.util.addPortletLink( 'p-tb', '#', 'Encode', 'tb-encode', 'Encode character(s)'); 
        $( link ).click( function ( event ) {
            event.preventDefault();
            encodeHTML();

        } );
    } );
} );
function encodeHTML() {
	rawStr = prompt( "What do you want to encode?");
	var encodedStr = rawStr.replace(/[\u00A0-\u9999<>\&]/g, function(i) {
		return '&#'+i.charCodeAt(0)+';';
	});
	alert( "The encoded string is: "+ encodedStr);
	copyToClipboard(encodedStr);
	mw.notify('Encoded string copied.');
}

function copyToClipboard(text) { // Taken from stackoverflow
    if (window.clipboardData && window.clipboardData.setData) {
        // Internet Explorer-specific code path to prevent textarea being shown while dialog is visible.
        return window.clipboardData.setData("Text", text);

    }
    else if (document.queryCommandSupported && document.queryCommandSupported("copy")) {
        var textarea = document.createElement("textarea");
        textarea.textContent = text;
        textarea.style.position = "fixed";  // Prevent scrolling to bottom of page in Microsoft Edge.
        document.body.appendChild(textarea);
        textarea.select();
        try {
            return document.execCommand("copy");  // Security exception may be thrown by some browsers.
        }
        catch (ex) {
            console.warn("Copy to clipboard failed.", ex);
            return prompt("Copy to clipboard: Ctrl+C, Enter", text);
        }
        finally {
            document.body.removeChild(textarea);
        }
    }
}