Adapted to recent changes in SWAG collection data structure

Author: delphidabbler

Src/FmSWAGImportDlg.pas

@@ -133,8 +133,8 @@   TSWAGImportDlg = class(TWizardDlg, INoPublicConstruct)
       ///  user database.</summary>
       fImporter: TSWAGImporter;
       ///  <summary>ID of currently selected category.</summary>
-      ///  <remarks>Set to empty string if no category is selected.</remarks>
-      fCurrentCatID: string;
+      ///  <remarks>Set to zero if no category is selected.</remarks>
+      fCurrentCatID: Cardinal;
     ///  <summary>Retrieves import directory name from edit control where it is
     ///  entered.</summary>
     function GetDirNameFromEditCtrl: string;
@@ -503,7 +503,7 @@ procedure TSWAGImportDlg.DisplayPacketsForCategory;
   CatIdx := lbCategories.ItemIndex;
   if CatIdx = -1 then
   begin
-    fCurrentCatID := '';
+    fCurrentCatID := 0;
     Exit;
   end;
   if fCurrentCatID = fSortedCategories[CatIdx].ID then

Src/SWAG.UCommon.pas

@@ -18,8 +18,8 @@ interface
 type
   ///  <summary>Record that encapsulates the data of a SWAG category.</summary>
   TSWAGCategory = record
-    ///  <summary>String that uniquely identifies a SWAG category.</summary>
-    ID: string;
+    ///  <summary>Number that uniquely identifies a SWAG category.</summary>
+    ID: Cardinal;
     ///  <summary>SWAG category title.</summary>
     Title: string;
   end;
@@ -31,7 +31,7 @@   TSWAGPacket = record
     ///  <summary>Number that uniquely identifies a SWAG packet.</summary>
     ID: Cardinal;
     ///  <summary>ID of SWAG category that packet belongs to.</summary>
-    Category: string;
+    Category: Cardinal;
     ///  <summary>File name of packet in original SWAG archive.</summary>
     FileName: string;
     ///  <summary>Date and time packet was added to or updated in the SWAG

Src/SWAG.UReader.pas

@@ -18,6 +18,7 @@ interface
 uses
   // Delphi
   SysUtils,
+  Generics.Defaults,
   Generics.Collections,
   // Project
   SWAG.UCommon,
@@ -58,7 +59,7 @@   TSWAGReader = class(TObject)
       ///  <para>Only partial information that summarises each packet is
       ///  stored.</para>
       ///  </remarks>
-      fPacketsByCategory: TDictionary<string,TList<TSWAGPacket>>;
+      fPacketsByCategory: TDictionary<Cardinal,TList<TSWAGPacket>>;
       ///  <summary>Object used to interogate SWAG XML file.</summary>
       fXMLProcessor: TSWAGXMLProcessor;
       ///  <summary>Default wrapper for calls to the local SWAG database.
@@ -85,15 +86,15 @@   TSWAGReader = class(TObject)
     procedure FetchCategories(CallWrapper: TSWAGCallbackWrapper);
     ///  <summary>Fetches summaries of all the packets contained in a given
     ///  SWAG category from the SWAG database.</summary>
-    ///  <param name="CatID">string [in] ID of category for which packet
+    ///  <param name="CatID">Cardinal [in] ID of category for which packet
     ///  summaries are required.</param>
     ///  <param name="CallWrapper">TSWAGCallbackWrapper [in] Callback that is
     ///  called and passed a closure which can retrive the required category
     ///  information from the database. If nil then the default callback passed
     ///  to the constructor is used.</param>
     ///  <remarks>The fetched packet summaries are cached in
     ///  fPacketsByCategory.</remarks>
-    procedure FetchPartialPackets(const CatID: string;
+    procedure FetchPartialPackets(const CatID: Cardinal;
       CallWrapper: TSWAGCallbackWrapper);
     ///  <summary>Fetches full details a packet from the SWAG database.
     ///  </summary>
@@ -147,7 +148,7 @@   TSWAGReader = class(TObject)
       CallWrapper: TSWAGCallbackWrapper = nil);
     ///  <summary>Gets summaries of all the packets contained in a given SWAG
     ///  category.</summary>
-    ///  <param name="CatID">string [in] ID of the required category.</param>
+    ///  <param name="CatID">Cardinal [in] ID of the required category.</param>
     ///  <param name="Packets">TList&lt;TSWAGPacket&gt; [in] Receives the
     ///  required list of packet summaries.</param>
     ///  <param name="CallWrapper">TSWAGCallbackWrapper [in] Callback that is
@@ -158,7 +159,7 @@   TSWAGReader = class(TObject)
     ///  CallWrapper is called to retrieve the required packets. On subsequent
     ///  calls for that category the packets summaries are read from a cache
     ///  and CallWrapper is not called.</remarks>
-    procedure GetPartialPackets(const CatID: string;
+    procedure GetPartialPackets(const CatID: Cardinal;
       const Packets: TList<TSWAGPacket>;
       CallWrapper: TSWAGCallbackWrapper = nil);
     ///  <summary>Gets full details a packet from the SWAG database.</summary>
@@ -222,9 +223,18 @@ constructor TSWAGReader.Create(const SWAGDBDir: string;
   inherited Create;
   fDefaultCallWrapper := DefaultSWAGCallbackWrapper;
   fCategories := TList<TSWAGCategory>.Create;
-  fPacketsByCategory := TObjectDictionary<string,TList<TSWAGPacket>>.Create(
+  fPacketsByCategory := TObjectDictionary<Cardinal,TList<TSWAGPacket>>.Create(
     [doOwnsValues],
-    TStringEqualityComparer.Create
+    TDelegatedEqualityComparer<Cardinal>.Create(
+      function (const Left, Right: Cardinal): Boolean
+      begin
+        Result := Left = Right;
+      end,
+      function (const Value: Cardinal): Integer
+      begin
+        Result := Integer(Value);
+      end
+    )
   );
   fPacketCache := TSWAGPacketCache.Create(MaxPacketCacheSize);
   fXMLProcessor := TSWAGXMLProcessor.Create;
@@ -301,7 +311,7 @@ procedure TSWAGReader.FetchCompletePackets(const PacketIDs: TList<Cardinal>;
   );
 end;
 
-procedure TSWAGReader.FetchPartialPackets(const CatID: string;
+procedure TSWAGReader.FetchPartialPackets(const CatID: Cardinal;
   CallWrapper: TSWAGCallbackWrapper);
 begin
   if not Assigned(CallWrapper) then
@@ -382,7 +392,7 @@ procedure TSWAGReader.GetCompletePackets(PacketIDs: TList<Cardinal>;
   end;
 end;
 
-procedure TSWAGReader.GetPartialPackets(const CatID: string;
+procedure TSWAGReader.GetPartialPackets(const CatID: Cardinal;
   const Packets: TList<TSWAGPacket>; CallWrapper: TSWAGCallbackWrapper);
 begin
   if not fPacketsByCategory.ContainsKey(CatID) then

Src/SWAG.UXMLProcessor.pas

@@ -18,6 +18,7 @@ interface
 
 uses
   // VCL
+  XMLIntf,
   Generics.Collections,
   // Project
   SWAG.UCommon,
@@ -47,8 +48,8 @@   TSWAGXMLProcessor = class(TObject)
       cCategoryNode           = 'category';
       cCategoryIDAttr         = 'id';
       cCategoryTitleNode      = 'title';
-      cPacketsNode            = 'snippets';
-      cPacketNode             = 'snippet';
+      cPacketsNode            = 'packets';
+      cPacketNode             = 'packet';
       cPacketIDAttr           = 'id';
       cPacketCatIdNode        = 'category-id';
       cPacketFileNameNode     = 'file-name';
@@ -91,6 +92,18 @@   TSWAGXMLProcessor = class(TObject)
     ///  <exception>ESWAGXMLProcessor raised if packet source code can&#39;t be
     ///  loaded.</exception>
     procedure GetPacketSourceCode(var Packet: TSWAGPacket);
+    ///  <summary>Read and validate a positive integer value from a node
+    ///  attribute</summary>
+    ///  <param name="Node">IXMLNode [in] Node whose attribute is to be read.
+    ///  </param>
+    ///  <param name="Attr">string [in] Name of attribute.</param>
+    ///  <param name="ErrMsg">string [in] Exception error messsage to be used on
+    ///  error.</param>
+    ///  <returns>Required postive integer value.</returns>
+    ///  <exception>ESWAGXMLProcessor raised if attribute value is missing or
+    ///  is not a positive integer.</exception>
+    function GetPositiveIntAttribute(Node: IXMLNode; const Attr: string;
+      const ErrMsg: string): Cardinal;
   public
     ///  <summary>Constructor that sets up object ready to to process XML.
     ///  </summary>
@@ -110,13 +123,13 @@   TSWAGXMLProcessor = class(TObject)
     procedure GetCategories(CatList: TList<TSWAGCategory>);
     ///  <summary>Gets partial information about all packets belonging to a
     ///  category from the SWAG XML file.</summary>
-    ///  <param name="CatID">string [in] ID of category for which packets are
+    ///  <param name="CatID">Cardinal [in] ID of category for which packets are
     ///  required.</param>
     ///  <param name="PacketList">TList&lt;TSWAGPacket&gt; [in] Receives list
     ///  of packets read.</param>
     ///  <exception>ESWAGXMLProcessor raised if partial packets can't be read
     ///  or are invalid.</exception>
-    procedure GetPartialPackets(const CatID: string;
+    procedure GetPartialPackets(const CatID: Cardinal;
       PacketList: TList<TSWAGPacket>);
     ///  <summary>Gets a single packet from the SWAG XML file.</summary>
     ///  <param name="PacketID">Cardinal [in] Unique ID of the required packet.
@@ -142,7 +155,6 @@ implementation
   Classes,
   IOUtils,
   ActiveX,
-  XMLIntf,
   Math,
   DateUtils,
   // Project
@@ -179,6 +191,7 @@ procedure TSWAGXMLProcessor.GetCategories(CatList: TList<TSWAGCategory>);
   sMissingNode = 'Invalid SWAG XML file: no categories information found';
   sMissingID = 'Invalid SWAG XML file: missing category ID';
   sMissingTitle = 'Invalid SWAG XML file: missing title for category "%s"';
+  sBadSourceID = 'Invalid SWAG XML file: invalid or missing category ID';
 begin
   CategoriesNode := fXMLDoc.FindNode(
     NodePath([cSWAGRootNode, cCategoriesNode])
@@ -188,9 +201,9 @@ procedure TSWAGXMLProcessor.GetCategories(CatList: TList<TSWAGCategory>);
   CategoryNodes := fXMLDoc.FindChildNodes(CategoriesNode, cCategoryNode);
   for CategoryNode in CategoryNodes do
   begin
-    Category.ID := CategoryNode.Attributes[cCategoryIDAttr];
-    if StrIsEmpty(Category.ID, True) then
-      raise ESWAGXMLProcessor.Create(sMissingID);
+    Category.ID := GetPositiveIntAttribute(
+      CategoryNode, cCategoryIDAttr, sBadSourceID
+    );
     Category.Title := TXMLDocHelper.GetSubTagText(
       fXMLDoc, CategoryNode, cCategoryTitleNode
     );
@@ -205,9 +218,12 @@ function TSWAGXMLProcessor.GetPacket(const PacketID: Cardinal): TSWAGPacket;
   AllPacketsNode: IXMLNode;
   PacketNode: IXMLNode;
   DateStr: string;
+  PacketCatID: Cardinal;
 resourcestring
   sPacketsNodeMissing = 'Invalid SWAG XML file: no packet information found';
   sPacketNotFound = 'Invalid SWAG XML file: packet with ID %d not found';
+  sBadPacketCategory = 'Invalid SWAG XML file: packet has invalid or missing '
+    + 'category ID';
 begin
   // Find required Packet node
   AllPacketsNode := fXMLDoc.FindNode(NodePath([cSWAGRootNode, cPacketsNode]));
@@ -220,9 +236,12 @@ function TSWAGXMLProcessor.GetPacket(const PacketID: Cardinal): TSWAGPacket;
     raise ESWAGXMLProcessor.CreateFmt(sPacketNotFound, [PacketID]);
   // Get Packet info from Packet node
   Result.ID := PacketID;
-  Result.Category := TXMLDocHelper.GetSubTagText(
-    fXMLDoc, PacketNode, cPacketCatIdNode
-  );
+  if not TryStrToCardinal(
+    TXMLDocHelper.GetSubTagText(fXMLDoc, PacketNode, cPacketCatIdNode),
+    PacketCatID
+  ) then
+    raise ESWAGXMLProcessor.Create(sBadPacketCategory);
+  Result.Category := PacketCatID;
   Result.FileName := TXMLDocHelper.GetSubTagText(
     fXMLDoc, PacketNode, cPacketFileNameNode
   );
@@ -255,12 +274,10 @@ procedure TSWAGXMLProcessor.GetPacketSourceCode(var Packet: TSWAGPacket);
 begin
   Assert(Packet.ID > 0, ClassName + '.GetPacketSourceCode: '
     + 'Packet.ID not set');
-  Assert(not StrIsEmpty(Packet.Category),
-    ClassName + '.GetPacketSourceCode: Packet.Category not set');
   Assert(not StrIsEmpty(Packet.FileName),
     ClassName + '.GetPacketSourceCode: Packet.FileName not set');
   FilePath := StrJoin(
-    [fSWAGRootDir, Packet.Category, Packet.FileName], PathDelim
+    [fSWAGRootDir, Packet.FileName], PathDelim
   );
   if not TFile.Exists(FilePath, False) then
     raise ESWAGXMLProcessor.CreateFmt(sSourceCodeNotFound, [Packet.ID]);
@@ -271,17 +288,17 @@ procedure TSWAGXMLProcessor.GetPacketSourceCode(var Packet: TSWAGPacket);
   Packet.SourceCode := Code;
 end;
 
-procedure TSWAGXMLProcessor.GetPartialPackets(const CatID: string;
+procedure TSWAGXMLProcessor.GetPartialPackets(const CatID: Cardinal;
   PacketList: TList<TSWAGPacket>);
 var
   AllPacketsNode: IXMLNode;
   PacketNodes: IXMLSimpleNodeList;
   PacketNode: IXMLNode;
   Packet: TSWAGPacket;
-  PacketID: Integer;
+  CatIDFromNode: Cardinal;
 resourcestring
   sPacketsNodeMissing = 'Invalid SWAG XML file: no packet information found';
-  sBadSourceID = 'Invalid SWAG XML file: invalid packet ID encountered';
+  sBadSourceID = 'Invalid SWAG XML file: missing or invalid packet ID';
 begin
   AllPacketsNode := fXMLDoc.FindNode(NodePath([cSWAGRootNode, cPacketsNode]));
   if not Assigned(AllPacketsNode) then
@@ -291,14 +308,14 @@ procedure TSWAGXMLProcessor.GetPartialPackets(const CatID: string;
     Exit;
   for PacketNode in PacketNodes do
   begin
-    if StrSameText(
+    if TryStrToCardinal(
       TXMLDocHelper.GetSubTagText(fXMLDoc, PacketNode, cPacketCatIdNode),
-      CatID
-    ) then
+      CatIDFromNode
+    ) and (CatIDFromNode > 0) and (CatIDFromNode = CatID) then
     begin
-      if not TryStrToInt(PacketNode.Attributes[cPacketIDAttr], PacketID) then
-        raise ESWAGXMLProcessor.Create(sBadSourceID);
-      Packet.ID := PacketID;
+      Packet.ID := GetPositiveIntAttribute(
+        PacketNode, cPacketIDAttr, sBadSourceID
+      );
       Packet.Title := TXMLDocHelper.GetSubTagText(
         fXMLDoc, PacketNode, cPacketTitleNode
       );
@@ -308,6 +325,13 @@ procedure TSWAGXMLProcessor.GetPartialPackets(const CatID: string;
   end;
 end;
 
+function TSWAGXMLProcessor.GetPositiveIntAttribute(Node: IXMLNode; const Attr,
+  ErrMsg: string): Cardinal;
+begin
+  if not TryStrToCardinal(Node.Attributes[Attr], Result) or (Result = 0) then
+    raise ESWAGXMLProcessor.Create(ErrMsg);
+end;
+
 procedure TSWAGXMLProcessor.Initialise(const SWAGDirName: string);
 resourcestring
   sFileReadError = 'Can''t read SWAG database file "%0:s"' + EOL2
@@ -352,14 +376,14 @@ class function TSWAGXMLProcessor.NodePath(const Tags: array of string): string;
 
 procedure TSWAGXMLProcessor.ValidatePacket(const Packet: TSWAGPacket);
 resourcestring
-  sBadCatID = 'Invalid SWAG XML file: packet %d has no category';
+  sBadCatID = 'Invalid SWAG XML file: packet %d has invalid category';
   sBadFileName = 'Invalid SWAG XML file: packet %d has no file name';
   sBadDateStamp = 'Invalid SWAG XML file: packet %d has no date stamp';
   sBadAuthor = 'Invalid SWAG XML file: packet %d has no author';
   sBadSourceCode = 'Invalid SWAG XML file: packet %d has no source code';
 begin
   ValidatePartialPacket(Packet);
-  if StrIsEmpty(Packet.Category, True) then
+  if Packet.Category = 0 then
     raise ESWAGXMLProcessor.CreateFmt(sBadCatID, [Packet.ID]);
   if StrIsEmpty(Packet.FileName, True) then
     raise ESWAGXMLProcessor.CreateFmt(sBadFileName, [Packet.ID]);