DataType refactoring preparation - Entity refactoring

src/Umbraco.Core/Models/PathValidationExtensions.cs

@@ -0,0 +1,115 @@
+using System;
+using System.IO;
+using Umbraco.Core.Logging;
+using Umbraco.Core.Models.Entities;
+using Umbraco.Core.Persistence.Dtos;
+
+namespace Umbraco.Core.Models
+{
+    /// <summary>
+    /// Provides extension methods for path validation.
+    /// </summary>
+    internal static class PathValidationExtensions
+    {
+        /// <summary>
+        /// Does a quick check on the entity's set path to ensure that it's valid and consistent
+        /// </summary>
+        /// <param name="entity"></param>
+        /// <returns></returns>
+        public static void ValidatePathWithException(this NodeDto entity)
+        {
+            //don't validate if it's empty and it has no id
+            if (entity.NodeId == default(int) && entity.Path.IsNullOrWhiteSpace())
+                return;
+
+            if (entity.Path.IsNullOrWhiteSpace())
+                throw new InvalidDataException($"The content item {entity.NodeId} has an empty path: {entity.Path} with parentID: {entity.ParentId}");
+
+            var pathParts = entity.Path.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
+            if (pathParts.Length < 2)
+            {
+                //a path cannot be less than 2 parts, at a minimum it must be root (-1) and it's own id
+                throw new InvalidDataException($"The content item {entity.NodeId} has an invalid path: {entity.Path} with parentID: {entity.ParentId}");
+            }
+
+            if (entity.ParentId != default(int) && pathParts[pathParts.Length - 2] != entity.ParentId.ToInvariantString())
+            {
+                //the 2nd last id in the path must be it's parent id
+                throw new InvalidDataException($"The content item {entity.NodeId} has an invalid path: {entity.Path} with parentID: {entity.ParentId}");
+            }
+        }
+
+        /// <summary>
+        /// Does a quick check on the entity's set path to ensure that it's valid and consistent
+        /// </summary>
+        /// <param name="entity"></param>
+        /// <returns></returns>
+        public static bool ValidatePath(this IUmbracoEntity entity)
+        {
+            //don't validate if it's empty and it has no id
+            if (entity.HasIdentity == false && entity.Path.IsNullOrWhiteSpace())
+                return true;
+
+            if (entity.Path.IsNullOrWhiteSpace())
+                return false;
+
+            var pathParts = entity.Path.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
+            if (pathParts.Length < 2)
+            {
+                //a path cannot be less than 2 parts, at a minimum it must be root (-1) and it's own id
+                return false;
+            }
+
+            if (entity.ParentId != default(int) && pathParts[pathParts.Length - 2] != entity.ParentId.ToInvariantString())
+            {
+                //the 2nd last id in the path must be it's parent id
+                return false;
+            }
+
+            return true;
+        }
+
+        /// <summary>
+        /// This will validate the entity's path and if it's invalid it will fix it, if fixing is required it will recursively
+        /// check and fix all ancestors if required.
+        /// </summary>
+        /// <param name="entity"></param>
+        /// <param name="logger"></param>
+        /// <param name="getParent">A callback specified to retrieve the parent entity of the entity</param>
+        /// <param name="update">A callback specified to update a fixed entity</param>
+        public static void EnsureValidPath<T>(this T entity,
+            ILogger logger,
+            Func<T, T> getParent,
+            Action<T> update)
+            where T: IUmbracoEntity
+        {
+            if (entity.HasIdentity == false)
+                throw new InvalidOperationException("Could not ensure the entity path, the entity has not been assigned an identity");
+
+            if (entity.ValidatePath() == false)
+            {
+                logger.Warn(typeof(UmbracoEntityExtensions), $"The content item {entity.Id} has an invalid path: {entity.Path} with parentID: {entity.ParentId}");
+                if (entity.ParentId == -1)
+                {
+                    entity.Path = string.Concat("-1,", entity.Id);
+                    //path changed, update it
+                    update(entity);
+                }
+                else
+                {
+                    var parent = getParent(entity);
+                    if (parent == null)
+                        throw new NullReferenceException("Could not ensure path for entity " + entity.Id + " could not resolve it's parent " + entity.ParentId);
+
+                    //the parent must also be valid!
+                    parent.EnsureValidPath(logger, getParent, update);
+
+                    entity.Path = string.Concat(parent.Path, ",", entity.Id);
+                    //path changed, update it
+                    update(entity);
+                }
+            }
+        }
+
+    }
+}