function processClick()

in modules/behavior/select.js [124:184]
44 lines of code
23 McCabe index (conditional complexity)

    function processClick(datum, isMultiselect) {
        var mode = context.mode();

        var entity = datum && datum.properties && datum.properties.entity;
        if (entity) datum = entity;

        if (datum && datum.type === 'midpoint') {
            datum = datum.parents[0];
        }

        if (datum instanceof osmEntity) {    // clicked an entity..
            var selectedIDs = context.selectedIDs();

            if (!isMultiselect) {
                if (selectedIDs.length > 1 && (!_suppressMenu && !isShowAlways)) {
                    // multiple things already selected, just show the menu...
                    mode.suppressMenu(false).reselect();
                } else {
                    // select a single thing..
                    context.enter(modeSelect(context, [datum.id]).suppressMenu(_suppressMenu));
                }

            } else {
                if (selectedIDs.indexOf(datum.id) !== -1) {
                    // clicked entity is already in the selectedIDs list..
                    if (!_suppressMenu && !isShowAlways) {
                        // don't deselect clicked entity, just show the menu.
                        mode.suppressMenu(false).reselect();
                    } else {
                        // deselect clicked entity, then reenter select mode or return to browse mode..
                        selectedIDs = selectedIDs.filter(function(id) { return id !== datum.id; });
                        context.enter(selectedIDs.length ? modeSelect(context, selectedIDs) : modeBrowse(context));
                    }
                } else {
                    // clicked entity is not in the selected list, add it..
                    selectedIDs = selectedIDs.concat([datum.id]);
                    context.enter(modeSelect(context, selectedIDs).suppressMenu(_suppressMenu));
                }
            }

        } else if (datum && datum.__featurehash__ && !isMultiselect) {    // clicked Data..
            context
                .enter(modeSelectData(context, datum));

        } else if (datum instanceof osmNote && !isMultiselect) {    // clicked a Note..
            context
                .enter(modeSelectNote(context, datum.id));

        } else if (datum instanceof qaError & !isMultiselect) {  // clicked an external QA error
            context
                .enter(modeSelectError(context, datum.id, datum.service));

        } else {    // clicked nothing..
            if (!isMultiselect && mode.id !== 'browse') {
                context.enter(modeBrowse(context));
            }
        }

        // reset for next time..
        _suppressMenu = true;
    }