Added arn to the main repository

arn/Postable.go

@@ -0,0 +1,47 @@
+package arn
+
+import (
+	"reflect"
+	"sort"
+)
+
+// Postable is a generic interface for Threads, Posts and Messages.
+type Postable interface {
+	Likeable
+
+	TitleByUser(*User) string
+	HTML() string
+	Parent() PostParent
+	Posts() []*Post
+	CountPosts() int
+	TypeName() string
+	Creator() *User
+
+	// Use Get prefix for these to avoid a
+	// name clash with the internal fields.
+	GetID() string
+	GetText() string
+	GetCreated() string
+	GetParentID() string
+}
+
+// ToPostables converts a slice of specific types to a slice of generic postables.
+func ToPostables(sliceOfPosts interface{}) []Postable {
+	var postables []Postable
+
+	v := reflect.ValueOf(sliceOfPosts)
+
+	for i := 0; i < v.Len(); i++ {
+		postable := v.Index(i).Interface().(Postable)
+		postables = append(postables, postable)
+	}
+
+	return postables
+}
+
+// SortPostablesLatestFirst ...
+func SortPostablesLatestFirst(posts []Postable) {
+	sort.Slice(posts, func(i, j int) bool {
+		return posts[i].GetCreated() > posts[j].GetCreated()
+	})
+}