package utils

import "github.com/vugu/vugu"

// AttributesAppend can be used to dynamically add entries to AttrMap attributes.
// This way you can add a class to a component that will not be overwritten by attributes set by the parent.
type AttributesAppend struct {
	AttrMap vugu.AttrMap

	Classes string
}

// AttributeList returns an attribute list corresponding to this map using the rules from VGNode.AddAttrInterface.
func (a AttributesAppend) AttributeList() (ret []vugu.VGAttribute) {
	combinedClasses := a.Classes
	if a.AttrMap != nil {
		if attrMapClassInt, ok := a.AttrMap["class"]; ok {
			if attrMapClass, ok := attrMapClassInt.(string); ok {
				if combinedClasses != "" {
					combinedClasses += " "
				}
				combinedClasses += attrMapClass
			}
		}
	}

	var n vugu.VGNode

	if combinedClasses != "" {
		n.AddAttrInterface("class", combinedClasses)
	}

	for k := range a.AttrMap {
		if k != "class" {
			n.AddAttrInterface(k, a.AttrMap[k])
		}
	}

	return n.Attr
}