From 56573899d3218a2858cfce76ea780a9e945907b0 Mon Sep 17 00:00:00 2001
From: Daniele Teti <d.teti@bittime.it>
Date: Tue, 29 Aug 2023 23:51:08 +0200
Subject: [PATCH] TMVCResponseBuilder and IMVCResponseBuilder (WIP)

---
 .gitignore                                    |   1 +
 .../funcion_actions_showcase/ControllerU.pas  |  32 +++++
 sources/MVCFramework.pas                      | 111 ++++++++++++++++++
 3 files changed, 144 insertions(+)

diff --git a/.gitignore b/.gitignore
index d94145c8..1bd99124 100644
--- a/.gitignore
+++ b/.gitignore
@@ -145,3 +145,4 @@ samples/WineCellarSample/winecellarclient_mobile/Android/Debug/styles-v21.xml
 samples/WineCellarSample/winecellarclient_mobile/Android/Debug/WineCellarMobileClient.classes/classes.dex
 samples/apachemodule/Apache24/logs/httpd.pid
 samples/session_file_based/Win32/DEBUG/sessions/
+unittests/general/UnitTestReports/
diff --git a/samples/funcion_actions_showcase/ControllerU.pas b/samples/funcion_actions_showcase/ControllerU.pas
index 8fb632d3..6ec604f8 100644
--- a/samples/funcion_actions_showcase/ControllerU.pas
+++ b/samples/funcion_actions_showcase/ControllerU.pas
@@ -70,6 +70,13 @@ type
     function GetMVCResponseWithObjectDictionary: IMVCResponse;
     [MVCPath('/mvcresponse/error')]
     function GetMVCErrorResponse: IMVCResponse;
+
+    { using MVCResponseBuilder }
+    [MVCPath('/mvcresponse/message/builder')]
+    function GetMVCResponseSimpleBuilder: IMVCResponse;
+    [MVCPath('/mvcresponse/data/builder')]
+    function GetMVCResponseWithDataBuilder: IMVCResponse;
+
   end;
 
 implementation
@@ -140,11 +147,36 @@ begin
   Result := MVCResponse(HTTP_STATUS.OK, 'My Message', 'My Reason String');
 end;
 
+function TMyController.GetMVCResponseSimpleBuilder: IMVCResponse;
+begin
+  Result := MVCResponseBuilder
+    .StatusCode(HTTP_STATUS.OK)
+    .Message('My Message')
+    .Reason('My Reason String')
+    .Build;
+
+  //Equivalent to the following
+  //
+  //Result := MVCResponse(HTTP_STATUS.OK, 'My Message', 'My Reason String');
+end;
+
 function TMyController.GetMVCResponseWithData: IMVCResponse;
 begin
   Result := MVCResponse(HTTP_STATUS.OK, TPerson.Create('Daniele','Teti', 99));
 end;
 
+function TMyController.GetMVCResponseWithDataBuilder: IMVCResponse;
+begin
+  Result := MVCResponseBuilder
+    .StatusCode(HTTP_STATUS.OK)
+    .Data(TPerson.Create('Daniele','Teti', 99))
+    .Build;
+
+  //Equivalent to the following
+  //
+  //Result := MVCResponse(HTTP_STATUS.OK, TPerson.Create('Daniele','Teti', 99));
+end;
+
 function TMyController.GetMVCResponseWithObjectDictionary: IMVCResponse;
 begin
   Result := MVCResponse(
diff --git a/sources/MVCFramework.pas b/sources/MVCFramework.pas
index aa6556ed..edfd5304 100644
--- a/sources/MVCFramework.pas
+++ b/sources/MVCFramework.pas
@@ -1154,6 +1154,19 @@ function CreateResponse(const StatusCode: UInt16; const ReasonString: string;
 function MVCResponse(AStatusCode: Integer; AMessage: string = ''; AReasonString: string = ''): IMVCResponse; overload;
 function MVCResponse(AStatusCode: Integer; AData: TObject; AReasonString: string = ''): IMVCResponse; overload;
 function MVCResponse(AStatusCode: Integer; AObjectDictionary: IMVCObjectDictionary; AReasonString: string = ''): IMVCResponse; overload;
+
+type
+  IMVCResponseBuilder = interface
+    ['{10210D72-AFAE-4919-936D-EB08AA16C01C}']
+    function StatusCode(const StatusCode: Integer): IMVCResponseBuilder;
+    function Message(const Message: String): IMVCResponseBuilder;
+    function Data(const Data: TObject): IMVCResponseBuilder;
+    function Reason(const Reason: String): IMVCResponseBuilder;
+    function ObjectDict(const ObjDictionary: IMVCObjectDictionary): IMVCResponseBuilder;
+    function Build: IMVCResponse;
+  end;
+
+function MVCResponseBuilder: IMVCResponseBuilder;
 // end - std responses
 
 implementation
@@ -1175,6 +1188,29 @@ var
   gHostingFramework: TMVCHostingFrameworkType = hftUnknown;
 
 
+type
+  TMVCResponseBuilder = class sealed(TInterfacedObject, IMVCResponseBuilder)
+  private
+    fBuilt: Boolean;
+  protected
+    fStatusCode: Integer;
+    fMessage: String;
+    fData: TObject;
+    fReason: String;
+    fObjectDict: IMVCObjectDictionary;
+
+    function StatusCode(const StatusCode: Integer): IMVCResponseBuilder;
+    function Message(const Message: String): IMVCResponseBuilder;
+    function Data(const Data: TObject): IMVCResponseBuilder;
+    function Reason(const Reason: String): IMVCResponseBuilder;
+    function ObjectDict(const ObjDictionary: IMVCObjectDictionary): IMVCResponseBuilder;
+    function Build: IMVCResponse;
+  public
+    constructor Create; virtual;
+    destructor Destroy; override;
+  end;
+
+
 function IsShuttingDown: Boolean;
 begin
   Result := gIsShuttingDown;
@@ -4589,9 +4625,84 @@ begin
   Result := TMVCResponse.Create(AStatusCode, AObjectDictionary, AReasonString);
 end;
 
+function MVCResponseBuilder: IMVCResponseBuilder;
+begin
+  Result := TMVCResponseBuilder.Create;
+end;
+
 // end - std responses
 
 
+{ TMVCResponseBuilder }
+
+function TMVCResponseBuilder.Build: IMVCResponse;
+begin
+  if (fData = nil) and (fObjectDict = nil) then
+  begin
+    Result := MVCResponse(fStatusCode, fMessage, fReason);
+  end
+  else
+  begin
+    if fData = nil then
+    begin
+      Result := MVCResponse(fStatusCode, fObjectDict, fReason);
+    end
+    else
+    begin
+      Result := MVCResponse(fStatusCode, fData, fReason);
+    end;
+  end;
+  fBuilt := True;
+end;
+
+constructor TMVCResponseBuilder.Create;
+begin
+  inherited;
+  fBuilt := False;
+end;
+
+function TMVCResponseBuilder.Data(const Data: TObject): IMVCResponseBuilder;
+begin
+  fData := Data;
+  Result := Self;
+end;
+
+destructor TMVCResponseBuilder.Destroy;
+begin
+  if not fBuilt then
+  begin
+    FreeAndNil(fData);
+  end;
+  inherited;
+end;
+
+function TMVCResponseBuilder.Message(
+  const Message: String): IMVCResponseBuilder;
+begin
+  fMessage := Message;
+  Result := Self;
+end;
+
+function TMVCResponseBuilder.ObjectDict(
+  const ObjDictionary: IMVCObjectDictionary): IMVCResponseBuilder;
+begin
+  fObjectDict := ObjDictionary;
+  Result := Self;
+end;
+
+function TMVCResponseBuilder.Reason(const Reason: String): IMVCResponseBuilder;
+begin
+  fReason := Reason;
+  Result := Self;
+end;
+
+function TMVCResponseBuilder.StatusCode(
+  const StatusCode: Integer): IMVCResponseBuilder;
+begin
+  fStatusCode := StatusCode;
+  Result := Self;
+end;
+
 initialization
 
 // https://quality.embarcadero.com/browse/RSP-38281