From dfcf19f186232087c90f9bcd3e28dacee3349273 Mon Sep 17 00:00:00 2001
From: Roland Bengtsson <roland.bengtsson@aholadigital.com>
Date: Fri, 6 Dec 2024 23:58:53 +0200
Subject: [PATCH] New BoldClassSubscriber component #20

---
 Source/BoldClassSubscriber.pas    | 277 ++++++++++++++++++++++++++++++
 Source/BoldClassSubscriberReg.pas | 113 ++++++++++++
 2 files changed, 390 insertions(+)
 create mode 100644 Source/BoldClassSubscriber.pas
 create mode 100644 Source/BoldClassSubscriberReg.pas

diff --git a/Source/BoldClassSubscriber.pas b/Source/BoldClassSubscriber.pas
new file mode 100644
index 0000000..ab95c2d
--- /dev/null
+++ b/Source/BoldClassSubscriber.pas
@@ -0,0 +1,277 @@
+unit BoldClassSubscriber;
+
+interface
+
+uses
+  Classes,
+  BoldHandles,
+  BoldSubscription,
+  BoldSystemRT,
+  BoldSystem;
+
+type
+  TBoldClassSubscriber = class;
+  TBoldClassEventMapping = class;
+  TBoldClassEventMappingCollection = class;
+  TEventMappingEnumerator = class;
+
+  TBoldClassSubscriptionEvent = procedure (AClassList: TBoldObjectList; ASubscriber: TBoldSubscriber) of object;
+
+  TBoldClassEventMapping = class(TCollectionItem)
+  private
+    fSubscriber: TBoldExtendedPassthroughSubscriber;
+    fClassTypeName: string;
+    fOnChange: TBoldExtendedEventHandler;
+    fOnSubscribe: TBoldClassSubscriptionEvent;
+    procedure SetClassTypeName(const Value: string);
+    function GetStaticSystemTypeInfo: TBoldSystemTypeInfo;
+    function GetCollection: TBoldClassEventMappingCollection;
+    procedure SetOnSubscribe(const Value: TBoldClassSubscriptionEvent);
+    procedure _Receive(Originator: TObject; OriginalEvent: TBoldEvent; RequestedEvent: TBoldRequestedEvent; const args: array of const);
+    function GetBoldSystem: TBoldSystem;
+  protected
+    function GetDisplayName: string; override;
+    property Collection: TBoldClassEventMappingCollection read GetCollection;
+    procedure PlaceSubscriptions;
+    property Subscriber: TBoldExtendedPassthroughSubscriber read fSubscriber;
+    property BoldSystem: TBoldSystem read GetBoldSystem;
+  public
+    constructor Create(Collection: TCollection); override;
+    destructor Destroy; override;
+    property StaticSystemTypeInfo: TBoldSystemTypeInfo read GetStaticSystemTypeInfo;
+    procedure Assign(Source: TPersistent); override;
+  published
+    property ClassTypeName: string read fClassTypeName write SetClassTypeName;
+    property OnChange: TBoldExtendedEventHandler read fOnChange write fOnChange;
+    property OnSubscribe: TBoldClassSubscriptionEvent read fOnSubscribe write SetOnSubscribe;
+  end;
+
+  TBoldClassEventMappingCollection = class(TCollection)
+  private
+    fBoldEventSubscriber: TBoldClassSubscriber;
+    function GetItem(Index: Integer): TBoldClassEventMapping;
+    procedure SetItem(Index: Integer; Value: TBoldClassEventMapping);
+    function GetEventSubscriber: TBoldClassSubscriber;
+  protected
+    function GetOwner: TPersistent; override;
+    property EventSubscriber: TBoldClassSubscriber read GetEventSubscriber;
+  public
+    constructor Create(AEventSubscriber: TBoldClassSubscriber);
+    function Add: TBoldClassEventMapping;
+    function GetEnumerator: TEventMappingEnumerator;
+    property Items[Index: Integer]: TBoldClassEventMapping read GetItem write SetItem; default;
+  end;
+
+  [ComponentPlatformsAttribute (pidWin32 or pidWin64)]
+  TBoldClassSubscriber = class(TBoldSystemExtensionComponent)
+  private
+    fEnabled: boolean;
+    fMappingCollection: TBoldClassEventMappingCollection;
+    procedure SetEnabled(const Value: boolean);
+    procedure SetEventMappingCollection(const Value: TBoldClassEventMappingCollection);
+  protected
+    procedure PlaceSubscriptions; override;
+  public
+    constructor Create(AOwner: TComponent); override;
+    destructor Destroy; override;
+  published
+    property Enabled: boolean read fEnabled write SetEnabled;
+    property EventMapping: TBoldClassEventMappingCollection read fMappingCollection write SetEventMappingCollection;
+  end;
+
+  TEventMappingEnumerator = class
+  private
+    FIndex: Integer;
+    FCollection: TBoldClassEventMappingCollection;
+  public
+    constructor Create(ACollection: TBoldClassEventMappingCollection);
+    function GetCurrent: TBoldClassEventMapping; inline;
+    function MoveNext: Boolean; inline;
+    property Current: TBoldClassEventMapping read GetCurrent;
+  end;
+
+implementation
+
+uses
+  System.SysUtils;
+
+{ TBoldClassSubscriber }
+
+constructor TBoldClassSubscriber.Create(AOwner: TComponent);
+begin
+  inherited;
+  FMappingCollection := TBoldClassEventMappingCollection.Create(Self);
+  fEnabled:= true;
+end;
+
+destructor TBoldClassSubscriber.Destroy;
+begin
+  FMappingCollection.free;
+  inherited;
+end;
+
+procedure TBoldClassSubscriber.PlaceSubscriptions;
+var
+  BoldEventMapping: TBoldClassEventMapping;
+begin
+  inherited;
+  for BoldEventMapping in FMappingCollection do
+    BoldEventMapping.PlaceSubscriptions;
+end;
+
+procedure TBoldClassSubscriber.SetEnabled(const Value: boolean);
+begin
+  if fEnabled <> Value then
+  begin
+    fEnabled := Value;
+    PlaceSubscriptions;
+  end;
+end;
+
+procedure TBoldClassSubscriber.SetEventMappingCollection(
+  const Value: TBoldClassEventMappingCollection);
+begin
+  fMappingCollection.Assign(Value);
+end;
+
+{ TBoldClassEventMapping }
+
+procedure TBoldClassEventMapping.Assign(Source: TPersistent);
+begin
+  if source is TBoldClassEventMapping then
+  begin
+    fOnChange := (Source as TBoldClassEventMapping).OnChange;
+    fOnSubscribe := (Source as TBoldClassEventMapping).OnSubscribe;
+  end
+  else
+    inherited;
+end;
+
+constructor TBoldClassEventMapping.Create(Collection: TCollection);
+begin
+  inherited;
+  fSubscriber := TBoldExtendedPassthroughSubscriber.CreateWithExtendedReceive(_Receive);
+end;
+
+destructor TBoldClassEventMapping.Destroy;
+begin
+  fSubscriber.Free;
+  inherited;
+end;
+
+function TBoldClassEventMapping.GetBoldSystem: TBoldSystem;
+begin
+  result := Collection.fBoldEventSubscriber.BoldSystem;
+end;
+
+function TBoldClassEventMapping.GetCollection: TBoldClassEventMappingCollection;
+begin
+  result := inherited Collection as TBoldClassEventMappingCollection;
+end;
+
+function TBoldClassEventMapping.GetDisplayName: string;
+begin
+  result := fClassTypeName;
+end;
+
+function TBoldClassEventMapping.GetStaticSystemTypeInfo: TBoldSystemTypeInfo;
+begin
+  result := nil;
+  if Assigned(Collection.fBoldEventSubscriber.StaticSystemHandle) then
+    result := Collection.fBoldEventSubscriber.StaticSystemHandle.StaticSystemTypeInfo;
+  if Collection.fBoldEventSubscriber.StaticSystemHandle = nil then
+    raise Exception.Create('StaticSystemHandle is nil');
+  if not Assigned(result) then
+    raise Exception.Create('StaticSystemTypeInfo is nil');
+end;
+
+procedure TBoldClassEventMapping.PlaceSubscriptions;
+begin
+  fSubscriber.CancelAllSubscriptions;
+  if Assigned(BoldSystem) and Assigned(fOnSubscribe) then
+    OnSubscribe(BoldSystem.ClassByExpressionName[fClassTypeName], Subscriber);
+end;
+
+procedure TBoldClassEventMapping.SetClassTypeName(const Value: string);
+begin
+  if fClassTypeName <> Value then
+  begin
+    fClassTypeName := Value;
+    PlaceSubscriptions;
+  end;
+end;
+
+procedure TBoldClassEventMapping.SetOnSubscribe(const Value: TBoldClassSubscriptionEvent);
+begin
+  fOnSubscribe := Value;
+end;
+
+procedure TBoldClassEventMapping._Receive(Originator: TObject; OriginalEvent: TBoldEvent;
+  RequestedEvent: TBoldRequestedEvent; const args: array of const);
+begin
+  if Assigned(OnChange) then
+    OnChange(Originator, OriginalEvent, RequestedEvent, args);
+end;
+
+{ TBoldClassEventMappingCollection }
+
+function TBoldClassEventMappingCollection.Add: TBoldClassEventMapping;
+begin
+  Result := TBoldClassEventMapping(inherited Add);
+end;
+
+constructor TBoldClassEventMappingCollection.Create(
+  AEventSubscriber: TBoldClassSubscriber);
+begin
+  inherited Create(TBoldClassEventMapping);
+  fBoldEventSubscriber := AEventSubscriber;
+end;
+
+function TBoldClassEventMappingCollection.GetEnumerator: TEventMappingEnumerator;
+begin
+  Result := TEventMappingEnumerator.Create(Self);
+end;
+
+function TBoldClassEventMappingCollection.GetEventSubscriber: TBoldClassSubscriber;
+begin
+  result := owner as TBoldClassSubscriber;
+end;
+
+function TBoldClassEventMappingCollection.GetItem(Index: Integer): TBoldClassEventMapping;
+begin
+  Result := TBoldClassEventMapping(inherited GetItem(Index));
+end;
+
+function TBoldClassEventMappingCollection.GetOwner: TPersistent;
+begin
+  result := fBoldEventSubscriber;
+end;
+
+procedure TBoldClassEventMappingCollection.SetItem(Index: Integer;
+  Value: TBoldClassEventMapping);
+begin
+  inherited SetItem(Index, Value);
+end;
+
+{ TEventMappingEnumerator }
+
+constructor TEventMappingEnumerator.Create(
+  ACollection: TBoldClassEventMappingCollection);
+begin
+  inherited Create;
+  FIndex := -1;
+  FCollection := ACollection;
+end;
+
+function TEventMappingEnumerator.GetCurrent: TBoldClassEventMapping;
+begin
+  Result := FCollection.Items[FIndex];
+end;
+
+function TEventMappingEnumerator.MoveNext: Boolean;
+begin
+  Inc(FIndex);
+  Result := FIndex < FCollection.Count;
+end;
+
+end.
diff --git a/Source/BoldClassSubscriberReg.pas b/Source/BoldClassSubscriberReg.pas
new file mode 100644
index 0000000..a8bf860
--- /dev/null
+++ b/Source/BoldClassSubscriberReg.pas
@@ -0,0 +1,113 @@
+unit BoldClassSubscriberReg;
+
+interface
+
+uses
+  Classes,
+  DesignEditors,
+  DesignIntf,
+  BoldAbstractPropertyEditors,
+  BoldPropertyEditors;
+
+type
+  TBoldClassSubscriberComponentEditor = class(TBoldComponentDblClickEditor)
+  protected
+    function GetDefaultMethodName: string; override;
+  public
+    procedure EditProperty(const PropertyEditor: IProperty; var Continue: Boolean); override;
+    procedure ExecuteVerb(Index: Integer); override;
+    function GetVerb(Index: Integer): string; override;
+    function GetVerbCount: Integer; override;
+  end;
+
+procedure Register;
+
+implementation
+
+uses
+  SysUtils,
+  BoldIdeConsts,
+  BoldClassSubscriber,
+  BoldElements,
+  BoldSystemRT,
+  Vcl.Controls;
+
+type
+  { TBoldTypeNameSelectorForExpressionSubscriber }
+  TBoldTypeNameSelectorForClassSubscriber = class(TBoldTypeNameSelectorForHandles)
+  protected
+    function GetApprovedTypes: TBoldValueTypes; override;
+    function GetContextType(Component: TPersistent): TBoldSystemTypeInfo; override;
+  end;
+
+procedure RegisterComponentsOnPalette;
+begin
+  RegisterComponents(BOLDPAGENAME_MISC,
+                     [
+                      TBoldClassSubscriber
+                     ]);
+end;
+
+procedure RegisterEditors;
+begin
+   RegisterComponentEditor(TBoldClassSubscriber, TBoldClassSubscriberComponentEditor);
+   RegisterPropertyEditor(TypeInfo(String), TBoldClassEventMapping, 'ClassTypeName', TBoldTypeNameSelectorForClassSubscriber);
+end;
+
+procedure Register;
+begin
+  RegisterComponentsOnPalette;
+  RegisterEditors;
+end;
+
+{ TBoldClassSubscriberComponentEditor }
+
+procedure TBoldClassSubscriberComponentEditor.EditProperty(const PropertyEditor: IProperty; var Continue: Boolean);
+begin
+  if PropertyEditor.GetName = 'EventMapping' then
+  begin
+    PropertyEditor.Edit;
+    Continue := False;
+  end;
+end;
+
+procedure TBoldClassSubscriberComponentEditor.ExecuteVerb(Index: Integer);
+begin
+  inherited;
+  case Index of
+    0: Edit;
+  end;
+end;
+
+function TBoldClassSubscriberComponentEditor.GetDefaultMethodName: string;
+begin
+  result := 'EventMapping';
+end;
+
+function TBoldClassSubscriberComponentEditor.GetVerb(Index: Integer): string;
+begin
+  case Index of
+    0: Result := 'Edit events...';
+  end;
+end;
+
+function TBoldClassSubscriberComponentEditor.GetVerbCount: Integer;
+begin
+  Result := 1;
+end;
+
+{ TBoldTypeNameSelectorForClassSubscriber }
+
+function TBoldTypeNameSelectorForClassSubscriber.GetApprovedTypes: TBoldValueTypes;
+begin
+  Result := [bvtClass];
+end;
+
+function TBoldTypeNameSelectorForClassSubscriber.GetContextType(Component: TPersistent): TBoldSystemTypeInfo;
+begin
+  Assert(Component is TBoldClassEventMapping, Component.ClassName);
+  result := TBoldClassEventMapping(Component).StaticSystemTypeInfo;
+  Assert(Assigned(result));
+end;
+
+end.