{ Base class for component stream tests.

  Copyright (C) 2020 Michael Van Canneyt michael@freepascal.org

  This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public
  License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version
  with the following modification:

  As a special exception, the copyright holders of this library give you permission to link this library with independent modules
  to produce an executable, regardless of the license terms of these independent modules,and to copy and distribute the resulting
  executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions
  of the license of that module. An independent module is a module which is not derived from or based on this library. If you
  modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do
  not wish to do so, delete this exception statement from your version.

  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details.

  You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free
  Software Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1335, USA.
}

{$mode objfpc}
{$h+}
unit tcstreaming;

interface

Uses
  SysUtils,Classes, fpcunit, testregistry;

Type

  { TTestStreaming }

  TTestStreaming = Class(TTestCase)
  Private
    FStream : TMemoryStream;
    FLastText : String;
    Function ReadByte : byte;
    Function ReadWord : Word;
    Function ReadInteger : LongInt;
    Function ReadNativeInt : NativeInt;
    function ReadBareStr: string;
    function ReadString(V : TValueType): string;
    function ReadWideString(V : TValueType): WideString;
    Procedure Fail(Fmt : String; Args : Array of const); overload;
  Public
    Procedure Setup; override;
    Procedure TearDown; override;
    Procedure ResetStream;
    Procedure SaveToStream(C : TComponent);
    Procedure LoadFromStream(C : TComponent);
    Procedure LoadFromTextStream(C : TComponent);
    Function ReadValue : TValueType;
    Procedure ExpectValue(AValue : TValueType);
    Procedure ExpectFlags(Flags : TFilerFlags; APosition : Integer);
    Procedure ExpectInteger(AValue : Integer);
    Procedure ExpectByte(AValue : Byte);
    Procedure ExpectInt64(AValue : NativeInt);
    Procedure ExpectBareString(AValue : String);
    Procedure ExpectString(AValue : String);
    Procedure ExpectSingle(AValue : Double);
    Procedure ExpectExtended(AValue : Extended);
    Procedure ExpectCurrency(AValue : Currency);
    Procedure ExpectIdent(AValue : String);
    Procedure ExpectDate(AValue : TDateTime);
    Procedure ExpectWideString(AValue : WideString);
    Procedure ExpectEndofList;
    Procedure ExpectSignature;
    Procedure ExpectEndOfStream;
    Procedure CheckAsString(const aData : String);
    Property LastText : String Read FLastText;
  end;

implementation

uses typinfo;

Function ValName(V : TValueType) : String;

begin
  Result:=GetEnumName(TypeInfo(TValueType),Ord(v));
end;

{ TTestStreaming }


procedure TTestStreaming.ExpectByte(AValue: Byte);

Var
  B : Byte;

begin
  B:=ReadByte;
  If (B<>AValue) then
    Fail('Expected byte %d, got %d',[AValue,B]);
end;

procedure TTestStreaming.ExpectCurrency(AValue: Currency);

Var
  C : Double;

begin
  ExpectValue(vaCurrency);
  FStream.ReadBufferData(C);
  If (C<>AValue) then
    Fail('Expected currency %f, got %f',[AValue,C]);
end;

procedure TTestStreaming.ExpectDate(AValue: TDateTime);

Var
  C : TDateTime;

begin
  ExpectValue(vaDate);
  FStream.ReadBufferData(C);
  If (C<>AValue) then
    Fail('Expected datetime %f, got %f',[AValue,C]);
end;

procedure TTestStreaming.ExpectEndofList;
begin
  ExpectValue(vaNull);
end;

procedure TTestStreaming.ExpectExtended(AValue: Extended);

Var
  E : Extended;

begin
  ExpectValue(vaExtended);
  FStream.ReadBufferData(E);
  If Abs(E-AValue)>0.01 then
    Fail('Expected extended %f, got %f',[AValue,E]);
end;

procedure TTestStreaming.ExpectFlags(Flags: TFilerFlags;
  APosition: Integer);

var
  FF : TFilerFlag;
  F : TFilerFlags;
  B : Byte;
  I : Integer;

begin
  F := [];
  I:=0;
  B:=ReadByte;
  if (B and $F0) = $F0 then
    begin
    F:=[];
    for FF in TFilerFlag do
      if (B and (1 shl ord(FF)))<>0 then
         Include(F,FF);
    if ffChildPos in Flags then
      I:=ReadInteger;
    end
  else
    FStream.Position:=FStream.Position-1;
  If (FLags<>F) then
    Fail('Wrong Flags');
  If I<>APosition then
    Fail('Wrong position, expected %d, got %d',[APosition,I]);
end;

procedure TTestStreaming.ExpectIdent(AValue: String);

var
  I,L : Byte;
  V : TValueType;
  S : String;
  C : Char;
begin
  V:=ReadValue;
  case V of
    vaIdent:
      begin
      L:=ReadByte;
      SetLength(S,L);
      for I:=1 to L do
        begin
        FStream.ReadBufferData(C);
        S[i]:=C;
        end;
      end;
    vaFalse:
      S := 'False';
    vaTrue:
      S := 'True';
    vaNil:
      S := 'nil';
    vaNull:
      S := 'Null';
  else
    Fail(Format('Expected identifier property type, got %s',[valName(V)]));
  end;
  If (S<>AValue) then
    Fail(Format('Wrong identifier %s, expected %s',[S,AValue]));
end;

procedure TTestStreaming.ExpectInt64(AValue: NativeInt);

Var
  V : TValueType;
  I : NativeInt;

begin
  V:=ReadValue;
  Case V of
    vaInt8  : I:=ReadByte;
    vaInt16 : I:=ReadWord;
    vaInt32 : I:=ReadInteger;
    vaInt64 : I:=ReadNativeInt;
  else
    Fail(Format('Expected integer property type, got %s',[valName(V)]));
  end;
  If (AValue<>I) then
    Fail(Format('Expected integer %d, but got %d',[AValue,I]));
end;

procedure TTestStreaming.ExpectInteger(AValue: Integer);

Var
  V : TValueType;
  I : Integer;

begin
  V:=ReadValue;
  Case V of
    vaInt8  : I:=ReadByte;
    vaInt16 : I:=ReadWord;
    vaInt32 : I:=ReadInteger;
  else
    Fail('Expected integer  property type, got %s',[valName(V)]);
  end;
  If (AValue<>I) then
    Fail('Expected integer %d, but got %d',[AValue,I]);
end;



procedure TTestStreaming.ExpectSignature;

const
  // Sig : array[1..4] of Char = 'TPF0';
  // Integer version of 4 chars 'TPF0'
  FilerSignatureInt = 809914452;

var
  E,L : Longint;

begin
  L:=ReadInteger;
  E:=FilerSignatureInt;
  if L<>E then
    Fail('Invalid signature %d, expected %d',[L,E]);
end;

procedure TTestStreaming.ExpectSingle(AValue: Double);

Var
  S : Double;

begin
  ExpectValue(vaSingle);
  FStream.ReadBufferData(S);
  If Abs(AValue-S)>0.0001 then
    Fail('Expected single %f, but got %s',[AValue,S]);
end;

function TTestStreaming.ReadString(V : TValueType): string;

var
  L,I : Integer;
  C : Char;

begin
  // There is only 1 string type
  if V<>vaString then
    Fail('Wrong type %s, expected string type.',[ValName(V)]);
  L := 0;
  FStream.ReadBufferData(L);
  SetLength(Result, L);
  For I:=1 to L do
    begin
    FStream.ReadBufferData(C);
    Result[i]:=C;
    end;
end;

function TTestStreaming.ReadWideString(V : TValueType): WideString;

begin
  Result := ReadString(V)
end;

procedure TTestStreaming.ExpectString(AValue: String);

Var
  V : TValueType;
  S : String;
begin
  V:=ReadValue;
  If v in [vaString,vaLstring,vaWString,vaUTF8String] then
    S:=ReadString(V)
  else
    Fail('Expected string type, but got : %s',[ValName(V)]);
  If (S<>AValue) then
    Fail('Expected string "%s", but got "%s"',[AVAlue,S]);
end;

procedure TTestStreaming.ExpectValue(AValue: TValueType);

Var
  V : TValueType;

begin
  V:=ReadValue;
  If (V<>AValue) then
    Fail('Expecting value %s, but read %s',[ValName(AValue),ValName(V)]);
end;

procedure TTestStreaming.ExpectWideString(AValue: WideString);

Var
  W : WideString;
  V : TValueType;

begin
  V:=ReadValue;
  If v in [vaString,vaLstring,vaWString,vaUTF8String] then
    W:=ReadWideString(V)
  else
    Fail('Expected string type, but got : %s',[ValName(V)]);
  If (W<>AValue) then
    Fail('Expected string "%s", but got "%s"',[AVAlue,W]);
end;


procedure TTestStreaming.Fail(Fmt: String; Args: array of Const);
begin
  Fail(Format(Fmt,Args));
end;

function TTestStreaming.ReadValue: TValueType;

var b : byte;

begin
  FStream.ReadBufferData(b);
  result := TValueType(b);
end;

procedure TTestStreaming.Setup;
begin
  FStream:=TMemoryStream.Create;
end;

procedure TTestStreaming.SaveToStream(C: TComponent);
begin
  C.Name:='Test'+C.ClassName;
  FStream.Clear;
  FStream.WriteComponent(C);
  FStream.Position:=0;
end;

procedure TTestStreaming.LoadFromStream(C: TComponent);
begin
  ResetStream;
  FStream.ReadComponent(C);
end;

procedure TTestStreaming.LoadFromTextStream(C: TComponent);

Var
  BS : TBytesStream;
  SS : TStringStream;

begin
  AssertTrue('Have text data',FLastText<>'');
  SS:=nil;
  SS:=TStringStream.Create(LastText);
  try
    BS:=TBytesStream.Create(Nil);
    ObjectTextToBinary(SS,BS);
    BS.Position:=0;
    BS.ReadComponent(C);
  finally
    SS.Free;
    BS.Free;
  end;
end;

procedure TTestStreaming.TearDown;
begin
  FreeAndNil(FStream);
end;

procedure TTestStreaming.ResetStream;
begin
  FStream.Position:=0;
end;

function TTestStreaming.ReadByte: byte;
begin
  FStream.ReadBufferData(Result);
end;

function TTestStreaming.ReadNativeInt: NativeInt;

begin
  FStream.ReadBufferData(Result);
end;

function TTestStreaming.ReadInteger: LongInt;
begin
  FStream.ReadBufferData(Result);
end;

function TTestStreaming.ReadWord: Word;
begin
  FStream.ReadBufferData(Result);
end;

function TTestStreaming.ReadBareStr: string;

var
  L,I : Integer;
  C : Char;

begin
  L:=ReadByte;
  SetLength(Result,L);
  for I:=1 to L do
    begin
    FStream.ReadBufferData(C);
    Result[I]:=C;
    end;
end;

procedure TTestStreaming.ExpectBareString(AValue: String);

Var
  S : String;

begin
  S:=ReadBareStr;
  If (S<>AValue) then
    Fail('Expected bare string %s, got :%s',[AValue,S]);
end;

procedure TTestStreaming.ExpectEndOfStream;
begin
  If (FStream.Position<>FStream.Size) then
    Fail('Expected at end of stream, current position=%d, size=%d',
          [FStream.Position,FStream.Size]);
end;

procedure TTestStreaming.CheckAsString(const aData: String);

Var
  SS : TStringStream;
  DS : String;
begin
  FStream.Position:=0;
  SS:=TStringStream.Create('');
  try
    ObjectBinaryToText(FStream,SS);
    DS:=SS.Datastring;
  finally
    SS.Free;
  end;
  AssertEquals('Stream to string',aData,DS);
  FLastText:=DS;
end;

end.