private _initEvents()

in src/core/echarts.ts [1061:1168]
75 lines of code
21 McCabe index (conditional complexity)

    private _initEvents(): void {
        each(MOUSE_EVENT_NAMES, (eveName) => {
            const handler = (e: ElementEvent) => {
                const ecModel = this.getModel();
                const el = e.target;
                let params: ECElementEvent;
                const isGlobalOut = eveName === 'globalout';
                // no e.target when 'globalout'.
                if (isGlobalOut) {
                    params = {} as ECElementEvent;
                }
                else {
                    el && findEventDispatcher(el, (parent) => {
                        const ecData = getECData(parent);
                        if (ecData && ecData.dataIndex != null) {
                            const dataModel = ecData.dataModel || ecModel.getSeriesByIndex(ecData.seriesIndex);
                            params = (
                                dataModel && dataModel.getDataParams(ecData.dataIndex, ecData.dataType, el) || {}
                            ) as ECElementEvent;
                            return true;
                        }
                        // If element has custom eventData of components
                        else if (ecData.eventData) {
                            params = extend({}, ecData.eventData) as ECElementEvent;
                            return true;
                        }
                    }, true);
                }

                // Contract: if params prepared in mouse event,
                // these properties must be specified:
                // {
                //    componentType: string (component main type)
                //    componentIndex: number
                // }
                // Otherwise event query can not work.

                if (params) {
                    let componentType = params.componentType;
                    let componentIndex = params.componentIndex;
                    // Special handling for historic reason: when trigger by
                    // markLine/markPoint/markArea, the componentType is
                    // 'markLine'/'markPoint'/'markArea', but we should better
                    // enable them to be queried by seriesIndex, since their
                    // option is set in each series.
                    if (componentType === 'markLine'
                        || componentType === 'markPoint'
                        || componentType === 'markArea'
                    ) {
                        componentType = 'series';
                        componentIndex = params.seriesIndex;
                    }
                    const model = componentType && componentIndex != null
                        && ecModel.getComponent(componentType, componentIndex);
                    const view = model && this[
                        model.mainType === 'series' ? '_chartsMap' : '_componentsMap'
                    ][model.__viewId];

                    if (__DEV__) {
                        // `event.componentType` and `event[componentTpype + 'Index']` must not
                        // be missed, otherwise there is no way to distinguish source component.
                        // See `dataFormat.getDataParams`.
                        if (!isGlobalOut && !(model && view)) {
                            warn('model or view can not be found by params');
                        }
                    }

                    params.event = e;
                    params.type = eveName;

                    (this._$eventProcessor as ECEventProcessor).eventInfo = {
                        targetEl: el,
                        packedEvent: params,
                        model: model,
                        view: view
                    };

                    this.trigger(eveName, params);
                }
            };
            // Consider that some component (like tooltip, brush, ...)
            // register zr event handler, but user event handler might
            // do anything, such as call `setOption` or `dispatchAction`,
            // which probably update any of the content and probably
            // cause problem if it is called previous other inner handlers.
            (handler as any).zrEventfulCallAtLast = true;
            this._zr.on(eveName, handler, this);
        });

        each(eventActionMap, (actionType, eventType) => {
            this._messageCenter.on(eventType, function (event: Payload) {
                (this as any).trigger(eventType, event);
            }, this);
        });

        // Extra events
        // TODO register?
        each(
            ['selectchanged'],
            (eventType) => {
                this._messageCenter.on(eventType, function (event: Payload) {
                    (this as any).trigger(eventType, event);
                }, this);
            }
        );

        handleLegacySelectEvents(this._messageCenter, this, this._api);
    }