Replace TUserDataProvider w/ TCollectionDataProvider

TUserDataProvider provided information about snippets & ctaegories from
the user database / collection. TCollectionDataProvider generalises
TUserDataProvider to provide information about snippets & categories
from any given collection.

TDatabase.Save was modified to use different TCollectionDataProvider
instances for saving both the "main" and "user" collections.

The previous reliance on the same TUserDataProvider instance for both
user and main collections was a bug which had only not materialised
because, as yet, the "main" collection does not have an associated
saver object and so nothing is saved.

Author: delphidabbler

Diff for: Src/DB.UMain.pas

@@ -54,33 +54,39 @@ interface
     evCategoryChanged       // a category's properties have changed
   );
 
-  {
-  IDBDataProvider:
-    Interface supported by objects that provides data about the categories and
-    snippets in the database.
-  }
+  ///  <summary>Interface supported by objects that provide information about
+  ///  categories and snippets.</summary>
   IDBDataProvider = interface(IInterface)
     ['{D2D57A0D-DB29-4012-891E-E817E0EED8C8}']
+
+    ///  <summary>Retrieves all the properties of a category.</summary>
+    ///  <param name="Cat"><c>Category</c> [in] Category for which properties
+    ///  are requested.</param>
+    ///  <returns><c>TCategoryData</c>. Record containing the property data.
+    ///  </returns>
     function GetCategoryProps(const Cat: TCategory): TCategoryData;
-      {Retrieves all the properties of a category.
-        @param Cat [in] Category for which data is requested.
-        @return Record containing property data.
-      }
+
+    ///  <summary>Retrieves names of all snippets that belong to a category.
+    ///  </summary>
+    ///  <param name="Cat"><c>Category</c> [in] Category for which snippet names
+    ///  are requested.</param>
+    ///  <returns><c>IStringList</c>. List of snippet names.</returns>
     function GetCategorySnippets(const Cat: TCategory): IStringList;
-      {Retrieves names of all snippets that belong to a category.
-        @param Cat [in] Category for which snippet names are requested.
-        @return Required list of snippet names.
-      }
+
+    ///  <summary>Retrieves all the properties of a snippet.</summary>
+    ///  <param name="Snippet"><c>TSnippet</c> [in] Snippet for which properties
+    ///  are requested.</param>
+    ///  <returns><c>TSnippetData</c>. Record containing the property data.
+    ///  </returns>
     function GetSnippetProps(const Snippet: TSnippet): TSnippetData;
-      {Retrieves all the properties of a snippet.
-        @param Snippet [in] Snippet for which data is requested.
-        @return Record containing property data.
-      }
+
+    ///  <summary>Retrieves information about all the references of a snippet.
+    ///  </summary>
+    ///  <param name="Snippet"><c>TSnippet</c> [in] Snippet for which references
+    ///  are requested.</param>
+    ///  <returns><c>TSnippetReferences</c>. Record containing references.
+    ///  </returns>
     function GetSnippetRefs(const Snippet: TSnippet): TSnippetReferences;
-      {Retrieves information about all the references of a snippet.
-        @param Snippet [in] Snippet for which information is requested.
-        @return Record containing references.
-      }
   end;
 
   {
@@ -106,11 +112,8 @@ interface
       depends on Kind. May be nil}
   end;
 
-  {
-  IDataItemFactory:
-    Interface to factory object that creates snippet and category objects. For
-    use by database loader objects.
-  }
+  ///  <summary>Interface to factory object that creates snippet and category
+  ///  objects use by collection loader objects.</summary>
   IDBDataItemFactory = interface(IInterface)
     ['{C6DD85BD-E649-4A90-961C-4011D2714B3E}']
 
@@ -301,12 +304,10 @@ implementation
 
 type
 
-  {
-  TDBDataItemFactory:
-    Class that can create category and snippet objects.
-  }
+  ///  <summary>Class that can create category and snippet objects.</summary>.
   TDBDataItemFactory = class(TInterfacedObject, IDBDataItemFactory)
   public
+
     ///  <summary>Creates a new category object.</summary>
     ///  <param name="CatID"><c>string</c> [in] ID of new category. Must be
     ///  unique.</param>
@@ -540,44 +541,59 @@       TEventInfo = class(TInterfacedObject, IDatabaseChangeEventInfo)
       }
   end;
 
-  {
-  TUserDataProvider:
-    Class that provides data about the categories and snippets in the user-
-    defined database.
-  }
-  TUserDataProvider = class(TInterfacedObject, IDBDataProvider)
+  ///  <summary>Class that provides data about the categories and snippets in
+  ///  a given collection.</summary>
+  TCollectionDataProvider = class(TInterfacedObject, IDBDataProvider)
   strict private
-    fSnippets: TSnippetList;    // All snippets in the whole database
-    fCategories: TCategoryList; // All categories in the whole database
+    var
+      fCollectionID: TCollectionID; // Collection on which to operate
+      fSnippets: TSnippetList;      // All snippets in the whole database
+      fCategories: TCategoryList;   // All categories in the whole database
   public
-    constructor Create(const SnipList: TSnippetList;
+    ///  <summary>Object constructor. Sets up data provider.</summary>
+    ///  <param name="ACollectionID"><c>TCollectionID</c> [in] Collection for
+    ///  which to provide data.</param>
+    ///  <param name="SnipList"><c>TSnippetList</c> [in] List of all snippets
+    ///  in the database.</param>
+    ///  <param name="Categories"><c>TCategoryList</c> [in] List of all
+    ///  categories in the database.</param>
+    constructor Create(const ACollectionID: TCollectionID;
+      const SnipList: TSnippetList;
       const Categories: TCategoryList);
-      {Constructor. Records list of all snippets and categories in both
-      databases.
-        @param SnipList [in] List of all snippets in whole database.
-        @param Categories [in] List of all categories in whole database.
-      }
-    { IDBDataProvider methods }
+
+    ///  <summary>Retrieves all the properties of a category.</summary>
+    ///  <param name="Cat"><c>Category</c> [in] Category for which properties
+    ///  are requested.</param>
+    ///  <returns><c>TCategoryData</c>. Record containing the property data.
+    ///  </returns>
+    ///  <remarks>Method of <c>IDBDataProvider</c></remarks>
     function GetCategoryProps(const Cat: TCategory): TCategoryData;
-      {Retrieves all the properties of a category.
-        @param Cat [in] Category for which data is requested.
-        @return Record containing property data.
-      }
+
+    ///  <summary>Retrieves names of all snippets from the collection that
+    ///  belong to a category.</summary>
+    ///  <param name="Cat"><c>Category</c> [in] Category for which snippet names
+    ///  are requested.</param>
+    ///  <returns><c>IStringList</c>. List of snippet names.</returns>
+    ///  <remarks>Method of <c>IDBDataProvider</c></remarks>
     function GetCategorySnippets(const Cat: TCategory): IStringList;
-      {Retrieves names of all user-defined snippets that belong to a category.
-        @param Cat [in] Category for which snippet names are requested.
-        @return Required list of snippet names.
-      }
+
+    ///  <summary>Retrieves all the properties of a snippet.</summary>
+    ///  <param name="Snippet"><c>TSnippet</c> [in] Snippet for which properties
+    ///  are requested.</param>
+    ///  <returns><c>TSnippetData</c>. Record containing the property data.
+    ///  </returns>
+    ///  <remarks>Method of <c>IDBDataProvider</c></remarks>
     function GetSnippetProps(const Snippet: TSnippet): TSnippetData;
-      {Retrieves all the properties of a snippet.
-        @param Snippet [in] Snippet for which data is requested.
-        @return Record containing property data.
-      }
+
+    ///  <summary>Retrieves information about all the references of a snippet.
+    ///  </summary>
+    ///  <param name="Snippet"><c>TSnippet</c> [in] Snippet for which references
+    ///  are requested.</param>
+    ///  <returns><c>TSnippetReferences</c>. Record containing references.
+    ///  </returns>
+    ///  <remarks>Method of <c>IDBDataProvider</c></remarks>
     function GetSnippetRefs(const Snippet: TSnippet): TSnippetReferences;
-      {Retrieves information about all the references of a snippet.
-        @param Snippet [in] Snippet for which information is requested.
-        @return Record containing references.
-      }
+
   end;
 
 function Database: IDatabase;
@@ -1030,15 +1046,12 @@ procedure TDatabase.Save;
   {Saves user defined snippets and all categories to user database.
   }
 var
-  Provider: IDBDataProvider;  // object that supplies info to writer
+  MainProvider, UserProvider: IDBDataProvider;  // object that supplies info to writer
   MainCollectionIdx, UserCollectionIdx: Integer;
   Saver: IDataFormatSaver;
   Collections: TCollections;
   Collection: TCollection;
 begin
-  // Create object that can provide required information about user database
-  Provider := TUserDataProvider.Create(fSnippets, fCategories);
-
   Collections := TCollections.Instance;
 
   {TODO: -cVault: The following code is a kludge to maintain compatibility with
@@ -1055,9 +1068,12 @@ procedure TDatabase.Save;
   if MainCollectionIdx >= 0 then
   begin
     Collection := Collections[MainCollectionIdx];
+    MainProvider := TCollectionDataProvider.Create(
+      TCollectionID.__TMP__MainDBCollectionID, fSnippets, fCategories
+    );
     Saver := TDatabaseIOFactory.CreateDBSaver(Collection);
     if Assigned(Saver) then
-      Saver.Save(fSnippets, fCategories, Provider);
+      Saver.Save(fSnippets, fCategories, MainProvider);
   end;
 
   UserCollectionIdx := TCollections.Instance.IndexOfID(
@@ -1066,9 +1082,12 @@ procedure TDatabase.Save;
   if UserCollectionIdx >= 0 then
   begin
     Collection := Collections[UserCollectionIdx];
+    UserProvider := TCollectionDataProvider.Create(
+      TCollectionID.__TMP__UserDBCollectionID, fSnippets, fCategories
+    );
     Saver := TDatabaseIOFactory.CreateDBSaver(Collection);
     if Assigned(Saver) then
-      Saver.Save(fSnippets, fCategories, Provider);
+      Saver.Save(fSnippets, fCategories, UserProvider);
   end;
 
   fUpdated := False;
@@ -1243,65 +1262,47 @@ function TDBDataItemFactory.CreateSnippet(const Name: string;
   Result := TSnippetEx.Create(Name, ACollectionID, Props);
 end;
 
-{ TUserDataProvider }
+{ TCollectionDataProvider }
 
-constructor TUserDataProvider.Create(const SnipList: TSnippetList;
-  const Categories: TCategoryList);
-  {Constructor. Records list of all snippets and categories in both databases.
-    @param SnipList [in] List of all snippets in whole database.
-    @param Categories [in] List of all categories in whole database.
-  }
+constructor TCollectionDataProvider.Create(const ACollectionID: TCollectionID;
+  const SnipList: TSnippetList; const Categories: TCategoryList);
 begin
   inherited Create;
+  fCollectionID := ACollectionID;
   fSnippets := SnipList;
   fCategories := Categories;
 end;
 
-function TUserDataProvider.GetCategoryProps(
+function TCollectionDataProvider.GetCategoryProps(
   const Cat: TCategory): TCategoryData;
-  {Retrieves all the properties of a category.
-    @param Cat [in] Category for which data is requested.
-    @return Record containing property data.
-  }
 begin
   Result.Desc := Cat.Description;
 end;
 
-function TUserDataProvider.GetCategorySnippets(
+function TCollectionDataProvider.GetCategorySnippets(
   const Cat: TCategory): IStringList;
-  {Retrieves names of all user-defined snippets that belong to a category.
-    @param Cat [in] Category for which snippet names are requested.
-    @return Required list of snippet names.
-  }
 var
   Snippet: TSnippet;  // references each snippet in category
 begin
   Result := TIStringList.Create;
   for Snippet in Cat.Snippets do
-    if Snippet.CollectionID <> TCollectionID.__TMP__MainDBCollectionID then
+    if Snippet.CollectionID = fCollectionID then
       Result.Add(Snippet.Name);
 end;
 
-function TUserDataProvider.GetSnippetProps(
+function TCollectionDataProvider.GetSnippetProps(
   const Snippet: TSnippet): TSnippetData;
-  {Retrieves all the properties of a snippet.
-    @param Snippet [in] Snippet for which data is requested.
-    @return Record containing property data.
-  }
 begin
   Result := (Snippet as TSnippetEx).GetProps;
 end;
 
-function TUserDataProvider.GetSnippetRefs(
+function TCollectionDataProvider.GetSnippetRefs(
   const Snippet: TSnippet): TSnippetReferences;
-  {Retrieves information about all the references of a snippet.
-    @param Snippet [in] Snippet for which information is requested.
-    @return Record containing references.
-  }
 begin
   Result := (Snippet as TSnippetEx).GetReferences;
 end;
 
+
 initialization