wikimedia/mediawiki-core

/*
 * Javascript for module editWarning
 */
( function () {
    'use strict';

    $( function () {
        var allowCloseWindow,
            $textBox = $( '#wpTextbox1' ),
            $summary = $( '#wpSummary' ),
            $both = $textBox.add( $summary );

        // Check if EditWarning is enabled and if we need it
        if ( !mw.user.options.get( 'useeditwarning' ) ) {
            return true;
        }

        // Save the original value of the text fields
        $both.each( function ( index, element ) {
            var $element = $( element );
            $element.data( 'origtext', $element.textSelection( 'getContents' ) );
        } );

        // This registers an event with the name "beforeunload.editwarning", which allows others to
        // turn the confirmation off with `$( window ).off( 'beforeunload.editwarning' );`.
        allowCloseWindow = mw.confirmCloseWindow( {
            test: function () {
                // When the action is submit we're solving a conflict. Everything is a pending change there.
                return mw.config.get( 'wgAction' ) === 'submit' ||
                    // We use .textSelection, because editors might not have updated the form yet.
                    $textBox.data( 'origtext' ) !== $textBox.textSelection( 'getContents' ) ||
                    $summary.data( 'origtext' ) !== $summary.textSelection( 'getContents' );
            },

            namespace: 'editwarning'
        } );

        // Add form submission handler
        $( '#editform' ).on( 'submit', function () {
            allowCloseWindow.release();
        } );
    } );

}() );