package cn.cloudwalk.event;

import cn.cloudwalk.cwos.client.event.EventClient;
import cn.cloudwalk.cwos.client.event.event.BaseEvent;
import cn.cloudwalk.cwos.client.event.event.CustomEvent;
import cn.cloudwalk.event.handler.CustomEventHandler;
import cn.cloudwalk.event.handler.EventHandler;
import cn.cloudwalk.event.handler.EventHandlerMapping;
import cn.cloudwalk.event.handler.EventHandlerWorker;
import cn.cloudwalk.event.listener.GroupEventListener;
import cn.cloudwalk.event.listener.GroupListnerClassMapping;
import cn.cloudwalk.event.task.EventHandleTask;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.CollectionUtils;

/**
 * 事件派发入口：基于 {@link cn.cloudwalk.event.handler.EventHandlerMapping} 选择处理器并委托
 * {@link cn.cloudwalk.event.handler.EventHandlerWorker} 执行。
 */
public class CloudwalkEventManager {
    private static final Logger LOGGER = LoggerFactory.getLogger(CloudwalkEventManager.class);
    private EventHandlerMapping eventHandlerMapping;
    private EventHandlerWorker eventHandlerWorker;
    private GroupListnerClassMapping groupListnerClassMapping;
    private EventClient eventClient;

    public void handle(Class<? extends GroupEventListener> eventListnerClass, BaseEvent baseEvent) {
        String groupId = this.groupListnerClassMapping.getGroupId(eventListnerClass);
        if (baseEvent instanceof CustomEvent) {
            Map<String, List<CustomEventHandler>> customByServiceCode = this.eventHandlerMapping
                .getServiceCodeCustomHandlerListMap(groupId, ((CustomEvent)baseEvent).getTopic());
            if (customByServiceCode == null) {
                customByServiceCode = Collections.emptyMap();
            }
            List<CustomEventHandler> customEventHandlers =
                (List<CustomEventHandler>)customByServiceCode.get(baseEvent.getServiceCode());
            eventHandle(baseEvent, customEventHandlers);
            return;
        }
        Map<String, List<EventHandler>> handlerByServiceCode =
            this.eventHandlerMapping.getServiceCodeHandlerListMap(groupId, baseEvent.getClass());
        if (handlerByServiceCode == null) {
            handlerByServiceCode = Collections.emptyMap();
        }
        List<EventHandler> handlerList = (List<EventHandler>)handlerByServiceCode.get(baseEvent.getServiceCode());
        eventHandle(baseEvent, handlerList);
    }

    private <H extends EventHandler> void eventHandle(BaseEvent baseEvent, List<H> handlers) {
        if (CollectionUtils.isEmpty(handlers)) {
            LOGGER.error("没有相应的事件处理程序");
            return;
        }
        for (EventHandler eventHandler : handlers) {
            this.eventHandlerWorker.work(new EventHandleTask(baseEvent, eventHandler));
        }
    }

    public void publish(BaseEvent baseEvent) {
        this.eventClient.pubEvent(baseEvent);
    }

    public void setEventHandlerMapping(EventHandlerMapping eventHandlerMapping) {
        this.eventHandlerMapping = eventHandlerMapping;
    }

    public EventHandlerMapping getEventHandlerMapping() {
        return this.eventHandlerMapping;
    }

    public void setEventHandlerWorker(EventHandlerWorker eventHandlerWorker) {
        this.eventHandlerWorker = eventHandlerWorker;
    }

    public void setEventClient(EventClient eventClient) {
        this.eventClient = eventClient;
    }

    public void setGroupListnerClassMapping(GroupListnerClassMapping groupListnerClassMapping) {
        this.groupListnerClassMapping = groupListnerClassMapping;
    }
}