function broadcast(componentName, eventName, params) {
  this.$children.forEach(child => {
    var name = child.$options.componentName;
    if (!name) {
      try {
        name =
          child.$el.attributes &&
          child.$el.attributes["name"] &&
          child.$el.attributes.name.value;
      } catch (e) {
        console.log(e.messsage);
      }
    }

    if (name === componentName) {
      child.$emit.apply(child, [eventName].concat(params));
    } else {
      broadcast.apply(child, [componentName, eventName].concat([params]));
    }
  });
}

// 查找组件
function findChild(componentName) {
  var existChild = null;
  this.$children.forEach(child => {
    var name = child.$options.name || child.$options.componentName;
    if (!name) {
      try {
        name =
          child.$el.attributes &&
          child.$el.attributes["name"] &&
          child.$el.attributes.name.value;
      } catch (e) {
        console.log(e.messsage);
      }
    }

    if (name === componentName) {
      existChild = child;
      return false;
    } else {
      var _subExistsChild = findChild.apply(child, [componentName]);
      if (_subExistsChild) {
        existChild = _subExistsChild;
      }
    }
  });

  return existChild;
}
export default {
  methods: {
    dispatch(componentName, eventName, params) {
      var parent = this.$parent || this.$root;
      var name = parent.$options.componentName;

      while (parent && (!name || name !== componentName)) {
        parent = parent.$parent;

        if (parent) {
          name = parent.$options.componentName;
        }
      }
      if (parent) {
        parent.$emit.apply(parent, [eventName].concat(params));
      }
    },
    broadcast(componentName, eventName, params) {
      broadcast.call(this, componentName, eventName, params);
    },
    findChild(componentName) {
      var root = this.$root;
      return findChild.call(root, componentName);
    }
  }
};