wikimedia/wikimedia-fundraising-dash

define( [
    'knockout',
    'text!components/filters/text-filter/text-filter.html',
    'operators'
], function ( ko, template, ops ) {

    function TextFilterViewModel( params ) {
        var self = this;

        this.operators = [
            ops.eq,
            ops.startswith,
            ops.endswith,
            ops.substringof
        ];
        this.selectedOperator = ko.observable( params.userChoices().operator || 'eq' );
        this.value = ko.observable( params.userChoices().value || '' );

        this.changed = function () {
            var value = self.value(),
                parts;

            params.userChoices( {
                operator: self.selectedOperator(),
                value: value
            } );

            if ( value === '' ) {
                params.queryString( '' );
                return;
            }
            parts = self.selectedOperator().split( '|' );

            if ( parts.length === 1 ) {
                params.queryString( params.name + ' ' + parts[ 0 ] + ' \'' + value + '\'' );
                return;
            }
            params.queryString( parts[ 1 ] + '(\'' + value + '\',' + params.name + ')' );
        };

        this.selectedOperator.subscribe( this.changed );
        this.value.subscribe( this.changed );
        this.changed();
    }

    return { viewModel: TextFilterViewModel, template: template };
} );