var
  Stream:TMemoryStream;
begin
  Stream:=TMemoryStream.Create;
  try
    SaveToStream(Stream);
    Stream.SaveToFile(FileName);
  finally
    Stream.Free;
  end;
end;

procedure TLineList.LoadFromStream(Stream:TStream);
var
  AObj:TLine;
begin
  Clear;
  Stream.Position:=0;
  while Stream.Position<Stream.Size do
  begin
    AObj:=Add;
    AObj.LoadFromStream(Stream);
  end;
end;

procedure TLineList.SaveToStream(Stream:TStream);
var
  i:Integer;
  AObj:TLine;
begin
  Stream.Size:=0;
  Stream.Position:=0;
  for i:=0 to FList.Count-1 do
  begin
    AObj:=Items[i];
    AObj.SaveToStream(Stream);
  end;
end;


{ TLine }

procedure TLine.Assign(aLine: TLine);
begin
  FLineId:=aLine.LineId;
  FCurState:=aLine.CurState;
  FLinkedDots.Assign(aLine.LinkedDots);
end;

constructor TLine.Create;
begin
  inherited Create;
  FLinkedDots:=TDotList.Create(False);
end;

destructor TLine.Destroy;
begin
  FLinkedDots.Free;
  inherited Destroy;
end;

procedure TLine.GetDLFromDots(List: TDotList);
begin

end;

procedure TLine.LoadFromStream(Stream: TStream);
begin
  //請在此處寫代碼
end;

procedure TLine.SaveState;
begin
  FOldState:=FCurState;
end;

procedure TLine.SaveToStream(Stream: TStream);
begin
  //請在此處寫代碼
end;


function TLine.StateChanged: Boolean;
begin
  Result:=FOldState<>FCurState;
end;

{ TDLControl }

procedure TDLControl.SetDotState(aDot:TDot; aState:TDotState;
  const bApply:Boolean);
begin
  aDot.DotState:=aState;
  if bApply then AnalyzeState;
end;

constructor TDLControl.Create;
begin
  inherited Create;
  FDots:=TDotList.Create(True);
  FLines:=TLineList.Create(True);
end;

destructor TDLControl.Destroy;
begin
  FDots.Free;
  FLines.Free;
  inherited Destroy;
end;

procedure TDLControl.LoadFromDataBase(aQuery:TADOQuery);

  procedure AddLine(aDot:TDot);
  var
    Index:Integer;
    aLine:TLine;
  begin
    with aQuery do
    begin
      Index:=FLines.IndexOf(Fields[3].AsInteger);
      if Index=-1 then
      begin
        aLine:=TLine.Create;
        FLines.Add(aLine);
        aLine.LineId:=Fields[3].AsInteger;
      end
      else
        aLine:=FLines.Items[Index];
      aLine.LinkedDots.Add(aDot);
      aDot.LinkedLines.Add(aLine);
    end;
  end;
  
var
  aDot:TDot;
  LastId:Integer;
begin
  FDots.Clear;
  FLines.Clear;
  LastId:=-1;
  aDot:=nil;
  with aQuery do
  begin
    Close;
    SQL.Clear;
    SQL.Add('select a.DotID, a.Type, a.kgState, b.LineID');
    SQL.Add('from t_CtrlDotsLayer a, t_DotLines b');
    SQL.Add('where a.UnitID=:UnitID and a.DotID=b.DotID');
    SQL.Add('order by a.DotID, b.LineID');
    SetParamValue(aQuery, 'UnitID', UnitID);
    Open;
    while not Eof do
    begin
      if LastId<>Fields[0].AsInteger then
      begin
        aDot:=TDot.Create;
        FDots.Add(aDot);
        aDot.DotId:=Fields[0].AsInteger;
        aDot.BDSDot:=Fields[1].AsInteger=0;
        if Fields[2].AsBoolean then
          aDot.DotState:=dsLink
        else
          aDot.DotState:=dsBreak;
        LastId:=Fields[0].AsInteger;
      end;
      AddLine(aDot);
      Next;
    end;
    Close;
  end;
end;

function TDotList.IndexOf(const DotId: Integer): Integer;
var
  i:Integer;
begin
  Result:=-1;
  for i:=0 to FList.Count-1 do
    if TDot(FList.Items[i]).DotId=DotId then
    begin
      Result:=i;
      Exit;
    end;
end;

function TDotList.FindDot(const DotId: Integer): TDot;
var
  Index:Integer;
begin
  Index:=IndexOf(DotId);
  Result:=TDot(FList.Items[Index]);
end;

procedure TDLControl.AnalyzeState;
var
  i:Integer;
  aDot:TDot;
  aDotList:TDotList;
begin
  for i:=0 to FDots.ItemCount-1 do
    FDots.Items[i].Checked:=False;
  {設(shè)置所有線路狀態(tài)為lsUnknown}
  for i:=0 to FLines.ItemCount-1 do
  begin
    FLines.Items[i].SaveState;
    FLines.Items[i].CurState:=lsUnknown;
  end;
  {分析每一個變電所的有電的線路}
  aDotList:=TDotList.Create(False);
  try
    GetBDSDots(aDotList);
    for i:=0 to aDotList.ItemCount-1 do
    begin
      aDot:=aDotList.Items[i];
      if not BDSNetWorkIsAnalyzed(aDot) then
        AnalyzeDot(aDot, True);   
    end;
  finally
    aDotList.Free;
  end;
  {設(shè)置所有l(wèi)sUnknown線路為無電}
  for i:=0 to FLines.ItemCount-1 do
  begin
    if FLines.Items[i].CurState=lsUnknown then
      FLines.Items[i].CurState:=lsOff;
  end;
end;

procedure TDLControl.GetBDSDots(List: TDotList);
var
  i:Integer;
  aDot:TDot;
begin
  if List.OwnerRec then
    raise Exception.Create('無法向列表中增加記錄對象，因為該列表只允許自己創(chuàng)建記錄對象！');
  List.Clear;
  for i:=0 to FDots.ItemCount-1 do
  begin
    aDot:=FDots.Items[i];
    if aDot.BDSDot then List.Add(FDots.Items[i]);
  end;  
end;

function TDLControl.BDSNetWorkIsAnalyzed(aBDSDot:TDot): Boolean;
  {如果變電所被分析過，則該變電所連通時，下面所有電路應(yīng)該有電。}
  function CheckLineList:Boolean;
  var
    i:Integer;
  begin
    Result:=True;
    if aBDSDot.DotState=dsLink then 
      for i:=0 to aBDSDot.LinkedLines.ItemCount-1 do
        if aBDSDot.LinkedLines.Items[i].CurState=lsUnknown then
        begin
          Result:=False;
          Exit;
        end;
  end;

begin
  if not aBDSDot.BDSDot then
    raise Exception.Create('該節(jié)點(diǎn)不是變電所對象！');
  if aBDSDot.LinkedLines.ItemCount=0 then
    Result:=True
  else
    Result:=CheckLineList;
end;

procedure TLineList.Assign(Source: TLineList);
var
  i:Integer;
  aItem:TLine;
begin
  Clear;
  for i:=0 to Source.ItemCount-1 do
  begin
    if OwnerRec then
    begin
      aItem:=Add;        
      aItem.Assign(Source.Items[i]);
    end
    else
      Add(Source.Items[i]);
  end;
end;

procedure TDotList.Assign(Source: TDotList);
var
  i:Integer;
  aItem:TDot;
begin
  Clear;
  for i:=0 to Source.ItemCount-1 do
  begin
    if OwnerRec then
    begin
      aItem:=Add;      
      aItem.Assign(Source.Items[i]);
    end
    else
      Add(Source.Items[i]);
  end;
end;

procedure TDotList.Remove(aDot: TDot);
var
  Index:Integer;
begin
  Index:=IndexOf(aDot.DotId);
  Delete(Index);
end;

procedure TDLControl.AnalyzeDot(aDot: TDot; const bInput:Boolean);
var
  i, j:Integer;
  aLine:TLine;
  aDotList:TDotList;
begin
  {整個分析過程如下：
       1、如果該節(jié)點(diǎn)連通，如果上層有輸入電流，則該節(jié)點(diǎn)下所有線路都有電，
       進(jìn)一步分析每一個線路的所有節(jié)點(diǎn)（遞歸調(diào)用該過程），如果上層無輸入
       電流，則該節(jié)點(diǎn)下所有電路狀態(tài)保持未知，分析流程返回。
       2，如果該節(jié)點(diǎn)斷開，則該節(jié)點(diǎn)下所有電路狀態(tài)保持未知，分析流程返回。}
  if aDot.Checked then Exit;
  aDot.Checked:=True;
  if (bInput) and (aDot.DotState=dsLink) then
  begin
    for i:=0 to aDot.LinkedLines.ItemCount-1 do
    begin
      aLine:=aDot.LinkedLines.Items[i];
      aLine.CurState:=lsOn;
      aDotList:=TDotList.Create(False);
      try
        aDotList.Assign(aDot.LinkedLines.Items[i].LinkedDots);
        aDotList.Remove(aDot);
        for j:=0 to aDotList.ItemCount-1 do
          AnalyzeDot(aDotList.Items[j], True);
      finally
        aDotList.Free;
      end;
    end;
  end;
end;

function TLineList.FindLine(const LineId: Integer): TLine;
var
  Index:Integer;
begin
  Index:=IndexOf(LineId);
  Result:=TLine(FList.Items[Index]);
end;

function TLineList.IndexOf(const LineId: Integer): Integer;
var
  i:Integer;
begin
  Result:=-1;
  for i:=0 to FList.Count-1 do
    if TLine(FList.Items[i]).LineId=LineId then
    begin
      Result:=i;
      Exit;
    end;
end;

procedure TDLControl.SaveState(aDot: TDot; aQuery: TADOQuery);
begin
  with aQuery do
  begin
    Close;
    SQL.Clear;
    SQL.Add('update t_CtrlDotsLayer');
    SQL.Add('set kgState=0');
    SQL.Add('where');
    SQL.Add('UnitID='+IntToStr(UnitID)+' and DotID='+IntToStr(aDot.DotId));
    ExecSQL;
  end;
end;

end.