unit DBFToolsUnit;

{$IFDEF FPC}
  {$mode objfpc}{$H+}
{$ENDIF}

interface

uses
  Classes, SysUtils, toolsunit,
  db, Dbf;

type
{ TDBFDBConnector }

  TDBFDBConnector = class(TDBConnector)
  protected
    procedure CreateNDatasets; override;
    procedure CreateFieldDataset; override;
    procedure DropNDatasets; override;
    procedure DropFieldDataset; override;
    Function InternalGetNDataset(n : integer) : TDataset; override;
    Function InternalGetFieldDataset : TDataSet; override;
  public
    function GetTraceDataset(AChange : Boolean) : TDataset; override;
  end;

  { TDbfTraceDataset }

  TDbfTraceDataset = class(Tdbf)
  protected
    procedure SetCurrentRecord(Index: Longint); override;
    procedure RefreshInternalCalcFields(Buffer: PChar); override;
    procedure InternalInitFieldDefs; override;
    procedure CalculateFields(Buffer: PChar); override;
    procedure ClearCalcFields(Buffer: PChar); override;
  end;

implementation

procedure TDBFDBConnector.CreateNDatasets;
var countID,n : integer;
begin
  for n := 0 to MaxDataSet do
    begin
    with TDbf.Create(nil) do
      begin
      FilePath := dbname;
      TableName := 'fpdev_'+inttostr(n)+'.db';
      FieldDefs.Add('ID',ftInteger);
      FieldDefs.Add('NAME',ftString,50);
      CreateTable;
      Open;
      if n > 0 then for countId := 1 to n do
        begin
        Append;
        FieldByName('ID').AsInteger := countID;
        FieldByName('NAME').AsString := 'TestName'+inttostr(countID);
        // Explicitly call .post, since there could be a bug which disturbs
        // the automatic call to post. (example: when TDataset.DataEvent doesn't
        // work properly)
        Post;
        end;
      if state = dsinsert then
        Post;
      Close;
      Free;
      end;
    end;
end;

procedure TDBFDBConnector.CreateFieldDataset;
var i : integer;
begin
  with TDbf.Create(nil) do
    begin
    FilePath := dbname;
    TableName := 'fpdev_field.db';
    FieldDefs.Add('ID',ftInteger);
    FieldDefs.Add('FSTRING',ftString,10);
    FieldDefs.Add('FSMALLINT',ftSmallint);
    FieldDefs.Add('FINTEGER',ftInteger);
//    FieldDefs.Add('FWORD',ftWord);
    FieldDefs.Add('FBOOLEAN',ftBoolean);
    FieldDefs.Add('FFLOAT',ftFloat);
//    FieldDefs.Add('FCURRENCY',ftCurrency);
//    FieldDefs.Add('FBCD',ftBCD);
    FieldDefs.Add('FDATE',ftDate);
//    FieldDefs.Add('FTIME',ftTime);
    FieldDefs.Add('FDATETIME',ftDateTime);
    FieldDefs.Add('FLARGEINT',ftLargeint);
    CreateTable;
    Open;
    for i := 0 to testValuesCount-1 do
      begin
      Append;
      FieldByName('ID').AsInteger := i;
      FieldByName('FSTRING').AsString := testStringValues[i];
      FieldByName('FSMALLINT').AsInteger := testSmallIntValues[i];
      FieldByName('FINTEGER').AsInteger := testIntValues[i];
      FieldByName('FBOOLEAN').AsBoolean := testBooleanValues[i];
      FieldByName('FFLOAT').AsFloat := testFloatValues[i];
      ShortDateFormat := 'yyyy-mm-dd';
      FieldByName('FDATE').AsDateTime := StrToDate(testDateValues[i]);
      FieldByName('FLARGEINT').AsLargeInt := testLargeIntValues[i];
      Post;
      end;
    Close;
    end;
end;

procedure TDBFDBConnector.DropNDatasets;
var n : integer;
begin
  for n := 0 to MaxDataSet do
    DeleteFile(ExtractFilePath(dbname)+PathDelim+'fpdev_'+inttostr(n)+'.db');
end;

procedure TDBFDBConnector.DropFieldDataset;
begin
  DeleteFile(ExtractFilePath(dbname)+PathDelim+'fpdev_field.db');
end;

function TDBFDBConnector.InternalGetNDataset(n: integer): TDataset;
begin
  Result := TDbf.Create(nil);
  with (result as TDbf) do
    begin
    FilePath := dbname;
    TableName := 'fpdev_'+inttostr(n)+'.db';
    end;
end;

function TDBFDBConnector.InternalGetFieldDataset: TDataSet;
begin
  Result := TDbf.Create(nil);
  with (result as TDbf) do
    begin
    FilePath := dbname;
    TableName := 'fpdev_field.db';
    end;
end;

function TDBFDBConnector.GetTraceDataset(AChange: Boolean): TDataset;
var ADS, AResDS : TDbf;
begin
  ADS := GetNDataset(AChange,15) as TDbf;
  AResDS := TDbfTraceDataset.Create(nil);
  AResDS.FilePath:=ADS.FilePath;
  AResDs.TableName:=ADS.TableName;
  Result:=AResDS;
end;

{ TDbfTraceDataset }

procedure TDbfTraceDataset.SetCurrentRecord(Index: Longint);
begin
  DataEvents := DataEvents + 'SetCurrentRecord' + ';';
  inherited SetCurrentRecord(Index);
end;

procedure TDbfTraceDataset.RefreshInternalCalcFields(Buffer: PChar);
begin
  DataEvents := DataEvents + 'RefreshInternalCalcFields' + ';';
  inherited RefreshInternalCalcFields(Buffer);
end;

procedure TDbfTraceDataset.InternalInitFieldDefs;
var i : integer;
    IntCalcFieldName : String;
begin
  // To fake a internal calculated field, set it's fielddef InternalCalcField
  // property to true, before the dataset is opened.
  // This procedure takes care of setting the automatically created fielddef's
  // InternalCalcField property to true. (works for only one field)
  IntCalcFieldName:='';
  for i := 0 to FieldDefs.Count -1 do
    if fielddefs[i].InternalCalcField then IntCalcFieldName := FieldDefs[i].Name;
  inherited InternalInitFieldDefs;
  if IntCalcFieldName<>'' then with FieldDefs.find(IntCalcFieldName) do
    begin
    InternalCalcField := True;
    end;
end;

procedure TDbfTraceDataset.CalculateFields(Buffer: PChar);
begin
  DataEvents := DataEvents + 'CalculateFields' + ';';
  inherited CalculateFields(Buffer);
end;

procedure TDbfTraceDataset.ClearCalcFields(Buffer: PChar);
begin
  DataEvents := DataEvents + 'ClearCalcFields' + ';';
  inherited ClearCalcFields(Buffer);
end;

initialization
  RegisterClass(TDBFDBConnector);
end.