code.grnet.gr Git - pithos-ms-client/blob - trunk/Pithos.OFM/Extensions.cs

   1 using System;\r
   2 using System.Collections.Generic;\r
   3 using System.Linq;\r
   4 using System.Text;\r
   5 using Pithos.Interfaces;\r
   6 \r
   7 namespace Pithos.OFM\r
   8 {\r
   9     static class Extensions\r
  10     {\r
  11         public static List<ObjectRecord> ToTree(this IEnumerable<ObjectInfo> enumerable)\r
  12         {\r
  13             //Order the items to ensure that children always come after their parents\r
  14             var orderedItems = enumerable.OrderBy(o => o.Uri.ToString());\r
  15             //Each item is stored in lookups\r
  16             var lookups = new Dictionary<string, ObjectRecord>();\r
  17 \r
  18             //RootNodes contains only the root nodes\r
  19             var rootNodes = new List<ObjectRecord>();\r
  20 \r
  21             foreach (var item in orderedItems)\r
  22             {\r
  23                 var path = item.Uri.ToString();\r
  24                 //Calculate the parent path\r
  25                 var parentPath = GetParentPath(path);\r
  26                 var parentName = GetParentPath(item.Name.ToString());\r
  27                 ObjectRecord parent;\r
  28 \r
  29 \r
  30                 //First ensure that the parent items exist\r
  31 \r
  32                 //We don't want to unescape here\r
  33                 var parts = item.Name.ToString().Split('/');\r
  34 \r
  35                 if (item.IsDirectory)\r
  36                 {\r
  37                     AddParentNodes(lookups, rootNodes, parts, item);\r
  38 \r
  39                     //Store each item using its current path\r
  40                     var newNode = new ObjectRecord { DisplayName = parts.Last(), ObjectInfo = item };\r
  41                     AddNode(rootNodes, lookups, newNode);\r
  42                 }\r
  43                 else\r
  44                 {\r
  45                     //Dont't add files\r
  46                     //But check to ensure that we DO have it's parent on record\r
  47                     //If it exist\r
  48                     if (lookups.TryGetValue(parentPath, out parent))\r
  49                     {\r
  50                         //Just continue\r
  51                         continue;\r
  52                     }\r
  53                     //If the item is directly below its parent container, there is no path to add\r
  54                     if (String.IsNullOrWhiteSpace(parentName))\r
  55                         continue;\r
  56                     //Otherwise we need to add it, because it is missing from the list\r
  57                     //Store each item using its current path\r
  58                     //Since this is not a directory, we won't add the item itself\r
  59                     AddParentNodes(lookups, rootNodes, parts, item);\r
  60                 }\r
  61             }\r
  62             return rootNodes;\r
  63         }\r
  64         private static void AddNode(List<ObjectRecord> rootNodes, Dictionary<string, ObjectRecord> lookups, ObjectRecord newNode)\r
  65         {\r
  66             ObjectRecord parent;\r
  67             var path = newNode.Uri.ToString();\r
  68             var parentPath = GetParentPath(path);\r
  69             lookups[path] = newNode;\r
  70 \r
  71             //If the record is a directory, we need to add it no matter what\r
  72 \r
  73             //If it is a file, we need to check that its parent node exists\r
  74             //If the parent node doesn't exist, we need to add a node for it.\r
  75             //We need to add nodes for all parents recursively,in case they don't exist\r
  76 \r
  77             //Does a parent item exist? \r
  78             if (lookups.TryGetValue(parentPath, out parent))\r
  79             {\r
  80                 //If so, add the current item under its parent\r
  81                 parent.Directories.Add(newNode);\r
  82                 parent.Directories.Sort((x, y) => String.CompareOrdinal(x.Uri.ToString(), y.Uri.ToString()));\r
  83             }\r
  84             else\r
  85                 //Otherwise add it to the list of root nodes\r
  86                 rootNodes.Add(newNode);\r
  87         }\r
  88 \r
  89         private static string GetParentPath(string path)\r
  90         {\r
  91             var lastIndex = path.LastIndexOf("/", StringComparison.Ordinal);\r
  92             if (lastIndex < 0)\r
  93                 return null;\r
  94             var parentPath = path.Substring(0, lastIndex);\r
  95             return parentPath;\r
  96         }\r
  97 \r
  98         private static void AddParentNodes(Dictionary<string, ObjectRecord> lookups, List<ObjectRecord> rootNodes, string[] parts, ObjectInfo item)\r
  99         {\r
 100             for (int i = 0; i < parts.Length - 1; i++)\r
 101             {\r
 102                 //The parts come from the ObjectInfo URI, therefore they should already be escaped\r
 103                 var nodeName = String.Join("/", parts, 0, i + 1);\r
 104                 var storageUri = GetStorageUri(item);\r
 105                 var nodeKey = String.Format("{0}/{1}/{2}/{3}", storageUri, item.Account, item.Container, nodeName);\r
 106                 //If the node was already addeds, skip\r
 107                 if (lookups.ContainsKey(nodeKey))\r
 108                     continue;\r
 109                 var newNode = new ObjectRecord\r
 110                 {\r
 111                     DisplayName = parts[i],\r
 112                     ObjectInfo = new ObjectInfo\r
 113                     {\r
 114                         Account = item.Account,\r
 115                         Container = item.Container,\r
 116                         Name = new Uri(nodeName, UriKind.Relative),\r
 117                         StorageUri = item.StorageUri,\r
 118                         Content_Type = "application/directory"\r
 119                     }\r
 120                 };\r
 121                 AddNode(rootNodes, lookups, newNode);\r
 122             }\r
 123         }\r
 124 \r
 125         private static string GetStorageUri(ObjectInfo item)\r
 126         {\r
 127             var storageParts = item.StorageUri.ToString().Split('/');\r
 128             var accountUri = String.Join("/", storageParts, 0, storageParts.Length - 1);\r
 129             return accountUri;\r
 130         }\r
 131 \r
 132     }\r
 133 }\r