import {Dispatcher} from "../mmviz-dispatch/index";

let dispatcher: Dispatcher = Dispatcher.getInstance();

export function addLegendItemToggleBehavior(parentSelector, selector){

    const selectorAll = parentSelector + " " + selector + " .legend-item",
        legendItems = document.querySelectorAll(selectorAll)
    ;

    Array.prototype.forEach.call(legendItems, (item) => {

        item.addEventListener("click", function(e) {

            let payload : any = {
                parentSelector: parentSelector,
                selector: selector,
                data: {
                    key: this.dataset.key,
                    variable: this.dataset.variable,
                    value: this.dataset.value,
                    valueattr: this.dataset.valueattr
                }
            };

            dispatcher.notify("click", payload);
        });
    });
}

export function addLegendItemToggleResponderBehavior(chart, legendSelector, dataPipeline, dataModelMaker){

    const chartLegendSelector = "toggle_" + chart.selector + legendSelector,
        legendToggleResponder = (payload) => {

        if (
            payload.parentSelector === chart.selector &&
            payload.selector === legendSelector
        ) {

            const key = payload.data.key,
                variable = payload.data.variable,
                value = payload.data.value,
                valueAttr = payload.data.valueattr,
                transformKey = "legend-toggle-" + variable + "-" + value,
                hasTransform = dataPipeline.hasTransformation(transformKey)
            ;
            let state = "on";

            if (!hasTransform){

                dataPipeline.addFilterTransform((d) => d[variable] !== value, transformKey);

                state = "off";
                chart.doMapColorScale = false;
            }
            else {
                dataPipeline.removeTransformByKey(transformKey);
                chart.doMapColorScale = true;
            }

            chart.dataModel = dataModelMaker();
            chart.updateView();
            chart.chartView.setLegendItemState(key, valueAttr, state);
        }
    };

    dispatcher.subscribe("click", chartLegendSelector, legendToggleResponder);
}