lazarus/components/synedit/syngutterlineoverview.pp

{-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------}

unit SynGutterLineOverview;

{$I synedit.inc}

interface

uses
  Classes, Graphics, Controls, LCLProc, LCLType, LCLIntf, Forms, FPCanvas, sysutils, math,
  SynGutterBase, SynEditTypes, LazSynEditText, SynEditTextBuffer, SynEditMarks,
  SynEditMiscClasses, SynEditFoldedView;

type
  TSynGutterLineOverview = class;
  TSynGutterLineOverviewProviderList = class;
  TSynGutterLOvLineMarks = class;

  { TSynGutterLOvMark }

  TSynGutterLOvMark = class
  private
    FColor: TColor;
    FColumn: Integer;
    FLine: Integer;
    FLineMarks: TSynGutterLOvLineMarks;
    FOnChange: TNotifyEvent;
    FOnDestroy: TNotifyEvent;
    FPriority: Integer;
  protected
    FData: Pointer;
  protected
    // for TSynGutterLOvLineMarks
    function CompareByPrior(Other: TSynGutterLOvMark): Integer;
    function CompareByLine(Other: TSynGutterLOvMark): Integer;
    procedure DoChange;
    property LineMarks: TSynGutterLOvLineMarks read FLineMarks write FLineMarks;
  public
    destructor Destroy; override;
    property Line: Integer read FLine;
    property Column: Integer read FColumn;
    property Color: TColor read FColor;
    property Priority: Integer read FPriority;
    property OnChange: TNotifyEvent read FOnChange write FOnChange;
    property OnDestroy: TNotifyEvent read FOnDestroy write FOnDestroy;
  end;

  { TSynGutterLOvMarkList }

  TSynGutterLOvMarkList = class(TFPList)
  private
    FOwnMarks: Boolean;
    FLockCount: Integer;
    FNeedSort: Boolean;
    function GetMark(Index: Integer): TSynGutterLOvMark;
    procedure PutMark(Index: Integer; const AValue: TSynGutterLOvMark);
  protected
    procedure ReSort; virtual;
  public
    constructor Create;
    destructor Destroy; override;
    procedure Lock;
    procedure UnLock;
    procedure Add(AValue: TSynGutterLOvMark); virtual;
    property Items[Index: Integer]: TSynGutterLOvMark read GetMark write PutMark; default;
  end;

  { TSynGutterLOvLineMarks
    List of TSynGutterLOvMark on a given Line (PixelLine)
  }

  TSynGutterLOvLineMarks = class(TSynGutterLOvMarkList)
  private
    FPixLine: Integer;
  protected
    procedure ReSort; override; // by prior
    procedure ReSortByLine;
    function Compare(Other: TSynGutterLOvLineMarks): Integer;
  public
    constructor Create;
    procedure Paint(Canvas: TCanvas; AClip: TRect; TopOffset: integer; AnItemHeight: Integer);
    procedure Add(AValue: TSynGutterLOvMark); override;
    property PixLine: Integer read FPixLine;
  end;

  { TSynGutterLOvLineMarksList
    List of (Pixel-)Lines with Marks
  }

  TSynGutterLOvLineMarksList = class(TFPList)
  private
    FItemHeight: Integer;
    FPixelHeight: Integer;
    FPixelPerLine: Integer;
    FTextLineCount: Integer;
    function GetLineMarks(Index: Integer): TSynGutterLOvLineMarks;
    procedure PutLineMarks(Index: Integer; const AValue: TSynGutterLOvLineMarks);
    function IndexForLine(ALine: Integer; PreviousIfNotExist: Boolean = False): Integer;
    function ItemForLine(ALine: Integer; CreateIfNotExists: Boolean = False): TSynGutterLOvLineMarks;
    procedure SetItemHeight(const AValue: Integer);
    procedure SetPixelHeight(const AValue: Integer);
    procedure SetTextLineCount(const AValue: Integer);
  protected
    procedure ReSort;
    procedure MarkChanged(Sender: TObject);
    procedure MarkDestroying(Sender: TObject);
    function TextLineToPixLine(ATxtLine: Integer): Integer;
    procedure ReBuild(AFromIndex: Integer = -1);
  public
    constructor Create;
    destructor Destroy; override;
    procedure AddMark(AMark: TSynGutterLOvMark);
    property Items[Index: Integer]: TSynGutterLOvLineMarks
      read GetLineMarks write PutLineMarks; default;
    property PixelHeight: Integer read FPixelHeight write SetPixelHeight;
    property TextLineCount: Integer read FTextLineCount write SetTextLineCount;
    property ItemHeight: Integer read FItemHeight write SetItemHeight;
  end;

  { TSynGutterLineOverviewProvider }

  TSynGutterLineOverviewProvider = class(TSynObjectListItem)
  private
    FColor: TColor;
    FHeight: Integer;
    FGutterPart: TSynGutterLineOverview;
    FPriority: Integer;
    FRGBColor: TColor;
    function  GetList: TSynGutterLineOverviewProviderList;
    procedure SetColor(const AValue: TColor);
    procedure SetHeight(const AValue: Integer);
    procedure SetPriority(const AValue: Integer);
  protected
    function  Compare(Other: TSynObjectListItem): Integer; override;
    procedure DoChange(Sender: TObject);

    procedure InvalidateTextLines(AFromLine, AToLine: Integer);
    procedure InvalidatePixelLines(AFromLine, AToLine: Integer);
    function  TextLineToPixel(ALine: Integer): Integer;
    function  TextLineToPixelEnd(ALine: Integer): Integer;
    function  PixelLineToText(ALineIdx: Integer): Integer;
    procedure ReCalc; virtual;                                                  // Does not invalidate

    function  SynEdit: TSynEditBase;
    property  Owner: TSynGutterLineOverviewProviderList read GetList; //the list
    property  GutterPart: TSynGutterLineOverview read FGutterPart;
    property  RGBColor: TColor read FRGBColor;

    procedure Paint(Canvas: TCanvas; AClip: TRect; TopOffset: integer); virtual;
  private
    FMarkList: TSynGutterLOvMarkList;
    function  GetMarks(AnIndex: Integer): TSynGutterLOvMark; virtual;
  protected
    function  MarksCount: Integer;
    property  Marks[AnIndex: Integer]: TSynGutterLOvMark read GetMarks;
  public
    constructor Create(AOwner: TComponent); override;
    destructor  Destroy; override;
    property Height: Integer read FHeight write SetHeight;
  published
    property Priority: Integer read FPriority write SetPriority;
    property Color: TColor read FColor write SetColor;
  end;

  { TSynGutterLineOverviewProviderList }

  TSynGutterLineOverviewProviderList = class(TSynObjectList)
  private
    function GetGutterPart: TSynGutterLineOverview;
    function GetProviders(AIndex: Integer): TSynGutterLineOverviewProvider;
  public
    constructor Create(AOwner: TComponent); override;
    property Owner: TSynGutterLineOverview read GetGutterPart;
    property Providers[AIndex: Integer]: TSynGutterLineOverviewProvider
             read GetProviders; default;
  end;

  { TSynGutterLOvProviderCurrentPage }

  TSynGutterLOvProviderCurrentPage = class(TSynGutterLineOverviewProvider)
  private
    FCurTopLine, FCurBottomLine: Integer;
    FFoldedTextBuffer: TSynEditFoldedView;
    FPixelTopLine, FPixelBottomLine: Integer;
    procedure SetFoldedTextBuffer(AValue: TSynEditFoldedView);
  protected
    procedure SynStatusChanged(Sender: TObject; Changes: TSynStatusChanges);
    procedure FoldChanged(aLine: Integer);

    procedure Paint(Canvas: TCanvas; AClip: TRect; TopOffset: integer); override;
    procedure ReCalc; override;
  public
    constructor Create(AOwner: TComponent); override;
    destructor  Destroy; override;
    property FoldedTextBuffer: TSynEditFoldedView read FFoldedTextBuffer write SetFoldedTextBuffer;
  end;

  { TSynGutterLOvProviderModifiedLines }

  TSynGutterLOvProviderModifiedLines = class(TSynGutterLineOverviewProvider)
  private
    FColorSaved, FRGBColorSaved: TColor;
    FPixLineStates: Array of TSynEditStringFlags;
    FFirstTextLineChanged, FLastTextLineChanged: Integer;
    procedure SetColorSaved(const AValue: TColor);
  protected
    procedure Paint(Canvas: TCanvas; AClip: TRect; TopOffset: integer); override;
    procedure ReScan;
    procedure ReCalc; override;

    procedure BufferChanged(Sender: TObject);
    procedure LineModified(Sender: TSynEditStrings; aIndex, aNewCount, aOldCount: Integer);
    procedure SynStatusChanged(Sender: TObject; Changes: TSynStatusChanges);
  public
    constructor Create(AOwner: TComponent); override;
    destructor  Destroy; override;
  published
    property ColorSaved: TColor read FColorSaved write SetColorSaved;
  end;

  { TSynGutterLOvProviderBookmarks }
  TSynGutterLOvProviderBookmarks = class;

  TSynGutterColorforMarkEvent = procedure(ASender: TSynGutterLOvProviderBookmarks;
                                          AMark: TSynEditMark;
                                          var AColor: TColor;
                                          var APriority: Integer) of object;

  TSynGutterLOvProviderBookmarks = class(TSynGutterLineOverviewProvider)
  private
    FOnColorForMark: TSynGutterColorforMarkEvent;
  protected
    procedure AdjustColorForMark(AMark: TSynEditMark; var AColor: TColor; var APriority: Integer); virtual;
    procedure DoMarkChange(Sender: TSynEditMark; Changes: TSynEditMarkChangeReasons);
    function CreateGutterMark(ASynMark: TSynEditMark): TSynGutterLOvMark;
    function IndexOfSynMark(ASynMark: TSynEditMark): Integer;
    procedure BufferChanging(Sender: TObject);
    procedure BufferChanged(Sender: TObject);
  public
    constructor Create(AOwner: TComponent); override;
    destructor  Destroy; override;
  published
    property OnColorForMark: TSynGutterColorforMarkEvent read FOnColorForMark write FOnColorForMark;
  end;

  TSynGutterLOvProviderCustom = class(TSynGutterLineOverviewProvider)
  end;

  { TSynChildWinControl
    Allow individual invalidates, for less painting
  }

  TSynChildWinControl = class(TCustomControl)
  public
    constructor Create(AOwner: TComponent); override;
  end;

  { TSynGutterLineOverview }
  TSynGutterLOvStateFlag = (losLineCountChanged, losResized, losASyncScheduled, losWaitForPaint);
  TSynGutterLOvStateFlags = set of TSynGutterLOvStateFlag;

  TSynGutterLineOverview = class(TSynGutterPartBase)
  private
    FProviders: TSynGutterLineOverviewProviderList;
    FWinControl: TSynChildWinControl;
    FLineMarks: TSynGutterLOvLineMarksList;
    FState: TSynGutterLOvStateFlags;
    function GetMarkHeight: Integer;
    procedure SetMarkHeight(const AValue: Integer);
    procedure ScheduleASync(AStates: TSynGutterLOvStateFlags);
    procedure ExecASync(Data: PtrInt);
  protected
    function  PreferedWidth: Integer; override;
    procedure Init; override;
    procedure LineCountChanged(Sender: TSynEditStrings; AIndex, ACount: Integer);
    procedure BufferChanged(Sender: TObject);
    procedure SetVisible(const AValue : boolean); override;
    procedure GutterVisibilityChanged; override;
    procedure DoChange(Sender: TObject); override;
  protected
    procedure InvalidateTextLines(AFromLine, AToLine: Integer);
    procedure InvalidatePixelLines(AFromLine, AToLine: Integer);
    function  TextLineToPixel(ALine: Integer): Integer;
    function  TextLineToPixelEnd(ALine: Integer): Integer;
    procedure DoResize(Sender: TObject); override;
    Procedure PaintWinControl(Sender: TObject);
  public
    destructor Destroy; override;
    procedure Assign(Source: TPersistent); override;
    procedure Paint(Canvas: TCanvas; AClip: TRect; FirstLine, LastLine: integer); override;
    procedure AddMark(AMark: TSynGutterLOvMark);

    property Providers: TSynGutterLineOverviewProviderList read FProviders;
  published
    property MarkHeight: Integer read GetMarkHeight write SetMarkHeight;
    property MarkupInfo;
  end;

implementation
uses
  SynEdit;

{ TSynGutterLOvMark }

function TSynGutterLOvMark.CompareByPrior(Other: TSynGutterLOvMark): Integer;
begin
  Result := Priority - Other.Priority;
  if Result <> 0 then exit;
  Result := Line - Other.Line;
  if Result <> 0 then exit;
  Result := Column - Other.Column;
  if Result <> 0 then exit;
  {$PUSH}{$Q-} // Overflow is allowed to occur
  Result := Integer(PtrUint(self) - PtrUInt(Other));
  {$POP}
end;

function TSynGutterLOvMark.CompareByLine(Other: TSynGutterLOvMark): Integer;
begin
  Result := Line - Other.Line;
  if Result <> 0 then exit;
  Result := Column - Other.Column;
  if Result <> 0 then exit;
  Result := Priority - Other.Priority;
  if Result <> 0 then exit;
  {$PUSH}{$Q-} // Overflow is allowed to occur
  Result := Integer(PtrUint(self) - PtrUInt(Other));
  {$POP}
end;

procedure TSynGutterLOvMark.DoChange;
begin
  if Assigned(FOnChange) then
    FOnChange(Self);
end;

destructor TSynGutterLOvMark.Destroy;
begin
  if Assigned(FOnDestroy) then
    FOnDestroy(Self);
  inherited Destroy;
end;

{ TSynGutterLOvMarkList }

function TSynGutterLOvMarkList.GetMark(Index: Integer): TSynGutterLOvMark;
begin
  Result := TSynGutterLOvMark(Get(Index));
end;

procedure TSynGutterLOvMarkList.PutMark(Index: Integer; const AValue: TSynGutterLOvMark);
begin
  Put(Index, AValue);
  ReSort;
end;

procedure TSynGutterLOvMarkList.Add(AValue: TSynGutterLOvMark);
begin
  inherited Add(AValue);
  ReSort;
end;

procedure TSynGutterLOvMarkList.ReSort;
begin
  // nothing
end;

constructor TSynGutterLOvMarkList.Create;
begin
  inherited;
  FOwnMarks := True;
end;

destructor TSynGutterLOvMarkList.Destroy;
begin
  if FOwnMarks then begin
    while Count > 0 do begin
      Items[0].Destroy;
      Delete(0);
    end;
  end;
  inherited Destroy;
end;

procedure TSynGutterLOvMarkList.Lock;
begin
  inc(FLockCount);
end;

procedure TSynGutterLOvMarkList.UnLock;
begin
  dec(FLockCount);
  if (FLockCount = 0) and FNeedSort then
    ReSort;
end;

{ TSynGutterLOvLineMarks }

function SynGutterLOvProviderLineMarksSort(Item1, Item2: Pointer): Integer;
begin
  Result := TSynGutterLOvMark(Item1).CompareByPrior(TSynGutterLOvMark(Item2));
end;

procedure TSynGutterLOvLineMarks.ReSort;
begin
  FNeedSort := FLockCount > 0;
  if FLockCount = 0 then
    Sort(@SynGutterLOvProviderLineMarksSort);
end;

function SynGutterLOvProviderLineMarksSortByLine(Item1, Item2: Pointer): Integer;
begin
  Result := TSynGutterLOvMark(Item1).CompareByLine(TSynGutterLOvMark(Item2));
end;

procedure TSynGutterLOvLineMarks.ReSortByLine;
begin
  if FLockCount > 0 then
    FNeedSort := True;
  Sort(@SynGutterLOvProviderLineMarksSortByLine);
end;

function TSynGutterLOvLineMarks.Compare(Other: TSynGutterLOvLineMarks): Integer;
begin
  Result := PixLine - Other.PixLine;
  if Result <> 0 then exit;
  {$PUSH}{$Q-} // Overflow is allowed to occur
  Result := PtrUint(self) - PtrUInt(Other);
  {$POP}
end;

constructor TSynGutterLOvLineMarks.Create;
begin
  inherited;
  FOwnMarks := False;
end;

procedure TSynGutterLOvLineMarks.Paint(Canvas: TCanvas; AClip: TRect; TopOffset: integer;
  AnItemHeight: Integer);
var
  bs: TFPBrushStyle;
begin
  if (FPixLine + AnItemHeight < AClip.Top - TopOffset) or
     (FPixLine > AClip.Bottom - TopOffset)
  then
    exit;

  AClip.Top    :=  FPixLine;
  AClip.Bottom := Max(FPixLine+1, FPixLine + AnItemHeight - 1);
  inc(AClip.Left);
  dec(AClip.Right);

  Canvas.Pen.Color := Items[0].Color;
  bs := Canvas.Brush.Style;
  Canvas.Brush.Style := bsClear;
  Canvas.Rectangle(AClip);
  Canvas.Brush.Style := bs;
end;

procedure TSynGutterLOvLineMarks.Add(AValue: TSynGutterLOvMark);
begin
  AValue.LineMarks := Self;
  inherited Add(AValue);
end;

{ TSynGutterLOvLineMarksList }

function TSynGutterLOvLineMarksList.GetLineMarks(Index: Integer): TSynGutterLOvLineMarks;
begin
  Result := TSynGutterLOvLineMarks(inherited Items[Index]);
end;

procedure TSynGutterLOvLineMarksList.PutLineMarks(Index: Integer;
  const AValue: TSynGutterLOvLineMarks);
begin
  inherited Items[Index] := AValue;
  Resort;
end;

function SynGutterLOvProviderLineMarksListSort(Item1, Item2: Pointer): Integer;
begin
  Result := TSynGutterLOvLineMarks(Item1).Compare(TSynGutterLOvLineMarks(Item2));
end;

procedure TSynGutterLOvLineMarksList.ReSort;
begin
  Sort(@SynGutterLOvProviderLineMarksListSort);
end;

procedure TSynGutterLOvLineMarksList.MarkChanged(Sender: TObject);
var
  LMark: TSynGutterLOvLineMarks;
  j: Integer;
begin
  LMark := TSynGutterLOvMark(Sender).LineMarks;
  j := TextLineToPixLine(TSynGutterLOvMark(Sender).Line);
  if (j >= LMark.PixLine) and (j < LMark.PixLine + ItemHeight) then begin
    LMark.ReSort;
    exit;
  end;
  LMark.Remove(Sender);
  if LMark.Count = 0 then begin
    Remove(LMark);
    LMark.Free;
  end;
  AddMark(TSynGutterLOvMark(Sender));
end;

procedure TSynGutterLOvLineMarksList.MarkDestroying(Sender: TObject);
var
  LMark: TSynGutterLOvLineMarks;
begin
  LMark := TSynGutterLOvMark(Sender).LineMarks;
  LMark.Remove(Sender);
  if LMark.Count = 0 then begin
    Remove(LMark);
    LMark.Free;
  end;
end;

function TSynGutterLOvLineMarksList.TextLineToPixLine(ATxtLine: Integer): Integer;
begin
  if PixelHeight < 1 then exit(0);

  Result := (Int64(ATxtLine) - 1) * Int64(PixelHeight) div TextLineCount;

  If FPixelPerLine * 2 < ItemHeight then
    dec(Result)
  else
  if FPixelPerLine > ItemHeight + 2 then
    inc(Result);

  if Result + ItemHeight > PixelHeight then Result := PixelHeight - ItemHeight;
  if Result < 0 then Result := 0;
end;

procedure TSynGutterLOvLineMarksList.ReBuild(AFromIndex: Integer = -1);

  procedure PushItemsDown(ASrc, ADest: TSynGutterLOvLineMarks);
  var
    i, j: Integer;
  begin
    i := ASrc.Count -1;
    while i >= 0 do begin
       j := TextLineToPixLine(ASrc[i].Line);
       if j >= ASrc.PixLine +ItemHeight then begin
         if (ADest.Count = 0) or (ADest.PixLine > j) then
           ADest.FPixLine := j;
         ADest.Add(ASrc[i]);
         ASrc.Delete(i);
       end;
       dec(i);
    end;
  end;

  procedure PullItemsUp(ADest, ASrc: TSynGutterLOvLineMarks);
  var
    i, j, NewLine: Integer;
  begin
    i := ASrc.Count -1;
    NewLine := MaxInt;
    while i >= 0 do begin
       j := TextLineToPixLine(ASrc[i].Line);
       if j < ADest.PixLine + ItemHeight then begin
         ADest.Add(ASrc[i]);
         ASrc.Delete(i);
       end
       else
         if j < NewLine then NewLine := j;
       dec(i);
    end;
    ASrc.FPixLine := NewLine;
  end;

var
  i, j, NewIdx: Integer;
  CurItem, NextItem, TmpItem: TSynGutterLOvLineMarks;
begin
  if Count = 0 then exit;

  if AFromIndex < 0 then begin
    NewIdx := -1;
    for i := 0 to Items[0].Count -1 do begin
      j := TextLineToPixLine(Items[0][i].Line);
      if (i = 0) or (j < NewIdx) then
        NewIdx := j;
    end;
    Items[0].FPixLine := NewIdx;
    AFromIndex := 0;
  end;

  TmpItem := TSynGutterLOvLineMarks.Create;
  TmpItem.Lock;
  NextItem := Items[AFromIndex];
  NextItem.Lock;
  while NextItem <> nil do begin
    if (TmpItem.Count > 0) and (TmpItem.PixLine < NextItem.PixLine) then begin
      Insert(AFromIndex, TmpItem);
      CurItem := TmpItem;
      TmpItem := TSynGutterLOvLineMarks.Create;
      TmpItem.Lock;
    end
    else
      CurItem := NextItem;

    inc(AFromIndex);
    if AFromIndex < Count then begin
      NextItem := Items[AFromIndex];
      NextItem.Lock;
      if NextItem.PixLine < CurItem.PixLine + ItemHeight then
        NextItem.FPixLine := CurItem.PixLine + ItemHeight;
    end
    else
      NextItem := nil;

    PushItemsDown(CurItem, TmpItem);
    PullItemsUp(CurItem, TmpItem);

    while NextItem <> nil do begin
      PullItemsUp(CurItem, NextItem);
      if NextItem.Count > 0 then
        break;
      Delete(AFromIndex);
      NextItem.Free;
      if AFromIndex < Count then begin
        NextItem := Items[AFromIndex];
        NextItem.Lock;
      end
      else
        NextItem := nil;
    end;

    if (TmpItem.Count > 0) and (NextItem = nil) then begin
      Insert(AFromIndex, TmpItem);
      NextItem := TmpItem;
      TmpItem := TSynGutterLOvLineMarks.Create;
      TmpItem.Lock;
    end;


    CurItem.UnLock;
    if CurItem.Count = 0 then begin
      Delete(AFromIndex - 1);
      dec(AFromIndex);
      CurItem.Free;
    end;
  end;
  TmpItem.Free;
end;

constructor TSynGutterLOvLineMarksList.Create;
begin
  FTextLineCount := 1;
  FItemHeight := 4;
  inherited;
end;

destructor TSynGutterLOvLineMarksList.Destroy;
begin
  while Count > 0 do begin
    Items[0].Destroy;
    Delete(0);
  end;
  inherited Destroy;
end;

procedure TSynGutterLOvLineMarksList.AddMark(AMark: TSynGutterLOvMark);
var
  i, PixLine: Integer;
  LMarks: TSynGutterLOvLineMarks;
begin
  AMark.OnChange := @MarkChanged;
  AMark.OnDestroy := @MarkDestroying;
  PixLine := TextLineToPixLine(AMark.Line);

  i := IndexForLine(PixLine, True);
  if i >= 0 then begin
    LMarks := Items[i];
    if (PixLine >= LMarks.PixLine) and (PixLine < LMarks.PixLine + ItemHeight) then begin
      LMarks.Add(AMark);
      // sendinvalidate
      exit;
    end;
  end;

  inc(i);
  LMarks := TSynGutterLOvLineMarks.Create;
  LMarks.FPixLine := PixLine;
  Insert(i, LMarks);

  LMarks.Add(AMark);
  // sendinvalidate

  if (i < Count - 1) and (Items[i+1].PixLine < LMarks.PixLine + ItemHeight) then
    ReBuild(i);
end;

function TSynGutterLOvLineMarksList.IndexForLine(ALine: Integer;
  PreviousIfNotExist: Boolean = False): Integer;
begin
  Result := Count - 1;
  while (Result >= 0) and (Items[Result].PixLine > ALine) do
    dec(Result);
  if ((Result >= 0) and (Items[Result].PixLine = ALine)) or (PreviousIfNotExist) then
    exit;
  Result := -1;
end;

function TSynGutterLOvLineMarksList.ItemForLine(ALine: Integer;
  CreateIfNotExists: Boolean): TSynGutterLOvLineMarks;
var
  i: Integer;
  LMarks: TSynGutterLOvLineMarks;
begin
  i := IndexForLine(ALine, CreateIfNotExists);
  if CreateIfNotExists and ( (i < 0) or (Items[i].PixLine <> ALine) ) then begin
    inc(i);
    LMarks := TSynGutterLOvLineMarks.Create;
    LMarks.FPixLine := i;
    Insert(i, LMarks);
  end;
  if  i >= 0 then
    Result := Items[i]
  else
    Result := nil;
end;

procedure TSynGutterLOvLineMarksList.SetItemHeight(const AValue: Integer);
begin
  if FItemHeight = AValue then exit;
  FItemHeight := AValue;
  ReBuild;
end;

procedure TSynGutterLOvLineMarksList.SetPixelHeight(const AValue: Integer);
begin
  if FPixelHeight = AValue then exit;
  FPixelHeight := AValue;
  FPixelPerLine := FPixelHeight div TextLineCount;
  ReBuild;
end;

procedure TSynGutterLOvLineMarksList.SetTextLineCount(const AValue: Integer);
begin
  if FTextLineCount = AValue then exit;
  FTextLineCount := Max(1, AValue);
  ReBuild;
end;

{ TSynGutterLineOverviewProvider }

constructor TSynGutterLineOverviewProvider.Create(AOwner: TComponent);
begin
  inherited;
  FGutterPart := Owner.Owner;
  FColor := clLtGray;
  FriendEdit := SynEdit;
  FMarkList := TSynGutterLOvMarkList.Create;
end;

destructor TSynGutterLineOverviewProvider.Destroy;
begin
  FreeAndNil(FMarkList);
  inherited Destroy;
end;

function TSynGutterLineOverviewProvider.GetList: TSynGutterLineOverviewProviderList;
begin
  Result := TSynGutterLineOverviewProviderList(inherited Owner);
end;

function TSynGutterLineOverviewProvider.GetMarks(AnIndex: Integer): TSynGutterLOvMark;
begin
  Result := FMarkList[Index];
end;

procedure TSynGutterLineOverviewProvider.SetColor(const AValue: TColor);
begin
  if FColor = AValue then exit;
  FColor := AValue;
  FRGBColor := TColor(ColorToRGB(AValue));
  DoChange(Self);
end;

procedure TSynGutterLineOverviewProvider.SetHeight(const AValue: Integer);
begin
  if FHeight = AValue then exit;
  FHeight := AValue;
  ReCalc;
end;

procedure TSynGutterLineOverviewProvider.SetPriority(const AValue: Integer);
begin
  if FPriority = AValue then exit;
  FPriority := AValue;
  Owner.Sort;
end;

function TSynGutterLineOverviewProvider.SynEdit: TSynEditBase;
begin
  Result := FGutterPart.SynEdit;
end;

function TSynGutterLineOverviewProvider.Compare(Other: TSynObjectListItem): Integer;
begin
  Result := Priority - TSynGutterLineOverviewProvider(Other).Priority;
  if Result = 0 then
    Result := inherited Compare(Other);
end;

procedure TSynGutterLineOverviewProvider.DoChange(Sender: TObject);
begin
  FGutterPart.DoChange(Sender);
end;

procedure TSynGutterLineOverviewProvider.InvalidateTextLines(AFromLine, AToLine: Integer);
begin
  FGutterPart.InvalidateTextLines(AFromLine, AToLine);
end;

procedure TSynGutterLineOverviewProvider.InvalidatePixelLines(AFromLine, AToLine: Integer);
begin
  FGutterPart.InvalidatePixelLines(AFromLine, AToLine);
end;

function TSynGutterLineOverviewProvider.TextLineToPixel(ALine: Integer): Integer;
var
  c: Integer;
begin
  if ALine < 0 then exit(-1);
  c := Max(1, TextBuffer.Count);
  if c = 0 then
    Result := -1
  else
    Result := (Int64(ALine - 1) * Int64(Height)) div c;
end;

function TSynGutterLineOverviewProvider.TextLineToPixelEnd(ALine: Integer): Integer;
var
  c, n: Integer;
begin
  if ALine < 0 then exit(-1);
  c := Max(1, TextBuffer.Count);
  if c = 0 then
    Result := -1
  else begin
    Result := (Int64(ALine - 1) * Int64(Height)) div c;
    n      := (Int64(ALine)     * Int64(Height)) div c - 1; // next line - 1 pix
    if n > Result then
      Result := n;
  end;
end;

function TSynGutterLineOverviewProvider.PixelLineToText(ALineIdx: Integer): Integer;
var
  c: Int64;
begin
  c := Max(1, TextBuffer.Count);
  if c = 0 then
    Result := -1
  else begin
    Result := (Int64(ALineIdx) * c) div Height + 1;
    if (Int64(Result - 1) * Int64(Height)) div c <> ALineIdx then
      inc(Result);
  end;
end;

procedure TSynGutterLineOverviewProvider.ReCalc;
begin
  // nothing
end;

procedure TSynGutterLineOverviewProvider.Paint(Canvas: TCanvas; AClip: TRect;
  TopOffset: integer);
begin
  // nothing
end;

function TSynGutterLineOverviewProvider.MarksCount: Integer;
begin
  Result := FMarkList.Count;
end;

{ TSynGutterLineOverviewProviderList }

function TSynGutterLineOverviewProviderList.GetGutterPart: TSynGutterLineOverview;
begin
  Result := TSynGutterLineOverview(inherited Owner);
end;

function TSynGutterLineOverviewProviderList.GetProviders(AIndex: Integer): TSynGutterLineOverviewProvider;
begin
  Result := TSynGutterLineOverviewProvider(BaseItems[AIndex]);
end;

constructor TSynGutterLineOverviewProviderList.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  Sorted := True;
end;

{ TSynGutterLOvProviderCurrentPage }

procedure TSynGutterLOvProviderCurrentPage.FoldChanged(aLine: Integer);
begin
  SynStatusChanged(nil, []);
end;

procedure TSynGutterLOvProviderCurrentPage.SetFoldedTextBuffer(AValue: TSynEditFoldedView);
begin
  if FFoldedTextBuffer <> nil then
    FFoldedTextBuffer.RemoveFoldChangedHandler(@FoldChanged);

  if FFoldedTextBuffer = AValue then Exit;
  FFoldedTextBuffer := AValue;

  if FFoldedTextBuffer <> nil then
    FFoldedTextBuffer.AddFoldChangedHandler(@FoldChanged);
end;

procedure TSynGutterLOvProviderCurrentPage.SynStatusChanged(Sender: TObject;
  Changes: TSynStatusChanges);
begin
  InvalidatePixelLines(FPixelTopLine, FPixelBottomLine);
  FCurTopLine := TCustomSynEdit(SynEdit).TopLine;
  FCurBottomLine := TCustomSynEdit(SynEdit).ScreenRowToRow(TCustomSynEdit(SynEdit).LinesInWindow);
  ReCalc;
  InvalidatePixelLines(FPixelTopLine, FPixelBottomLine);
end;

procedure TSynGutterLOvProviderCurrentPage.ReCalc;
begin
  FPixelTopLine    := TextLineToPixel(FCurTopLine);
  FPixelBottomLine := TextLineToPixelEnd(FCurBottomLine - 1);
end;

procedure TSynGutterLOvProviderCurrentPage.Paint(Canvas: TCanvas; AClip: TRect;
  TopOffset: integer);
begin
  if (FPixelBottomLine < AClip.Top - TopOffset) or
     (FPixelTopLine > AClip.Bottom - TopOffset)
  then
    exit;

  AClip.Top    := Max(AClip.Top, FPixelTopLine+TopOffset);
  AClip.Bottom := Min(AClip.Bottom, FPixelBottomLine+TopOffset);
  Canvas.Brush.Color := FRGBColor;
  Canvas.FillRect(AClip);
end;

constructor TSynGutterLOvProviderCurrentPage.Create(AOwner: TComponent);
begin
  inherited;
  FColor := 0;
  Color := $C0C0C0;
  TCustomSynEdit(SynEdit).RegisterStatusChangedHandler(@SynStatusChanged,
                                                 [scTopLine, scLinesInWindow]);
end;

destructor TSynGutterLOvProviderCurrentPage.Destroy;
begin
  TCustomSynEdit(SynEdit).UnRegisterStatusChangedHandler(@SynStatusChanged);
  inherited;
end;

{ TSynGutterLOvProviderModifiedLines }

procedure TSynGutterLOvProviderModifiedLines.SetColorSaved(const AValue: TColor);
begin
  if FColorSaved = AValue then exit;
  FColorSaved := AValue;
  FRGBColorSaved := TColor(ColorToRGB(AValue));
  DoChange(Self);
end;

procedure TSynGutterLOvProviderModifiedLines.Paint(Canvas: TCanvas; AClip: TRect;
  TopOffset: integer);
var
  i, i2, imax: Integer;
  State: TSynEditStringFlags;
begin
  if FFirstTextLineChanged > 0 then ReScan;

  AClip.Right := AClip.Left + 3;
  i := AClip.Top - TopOffset;
  imax := AClip.Bottom - TopOffset;
  if imax > high(FPixLineStates) then imax := high(FPixLineStates);
  while i <= imax do begin
    i2 := i+1;
    State := FPixLineStates[i];
    while (i2 <= imax) and (FPixLineStates[i2] = State) do
      inc(i2);

    if State <> [] then begin
      AClip.Top    := i;
      AClip.Bottom := i2;
      if sfSaved in State then
        Canvas.Brush.Color := FRGBColorSaved
      else
        Canvas.Brush.Color := FRGBColor;
      Canvas.FillRect(AClip);
    end;

    i := i2;
  end;
end;

procedure TSynGutterLOvProviderModifiedLines.ReScan;
var
  i, PixLine, PixLineEnd, CurPixLineEnd, TxtIndex, TxtIndexEnd: Integer;
  NewState: TSynEditStringFlags;
begin
  SetLength(FPixLineStates, Height);

  PixLine := TextLineToPixel(FFirstTextLineChanged);
  if PixLine < 0 then PixLine := 0;

  if FLastTextLineChanged = 0 then
    PixLineEnd := TextLineToPixelEnd(TextBuffer.Count)
  else
    PixLineEnd := TextLineToPixelEnd(FLastTextLineChanged);
  if PixLineEnd < PixLine then PixLineEnd := PixLine;
  if PixLineEnd >= Height then PixLineEnd := Height - 1;

  while PixLine <= PixLineEnd do begin
    NewState := [];
    TxtIndex := PixelLineToText(PixLine) - 1;
    CurPixLineEnd := TextLineToPixelEnd(TxtIndex + 1);
    TxtIndexEnd := PixelLineToText(CurPixLineEnd + 1) - 1;

    while TxtIndex < TxtIndexEnd do begin
      NewState := NewState + TSynEditStringList(TextBuffer).Flags[TxtIndex];
      inc(TxtIndex);
    end;

    for i := PixLine to CurPixLineEnd do
      FPixLineStates[i] := NewState;
    PixLine := CurPixLineEnd + 1;
  end;

  FFirstTextLineChanged := -1;;
  FLastTextLineChanged := -1;;
end;

procedure TSynGutterLOvProviderModifiedLines.ReCalc;
begin
  FFirstTextLineChanged := 1;
  FLastTextLineChanged := 0;
end;

procedure TSynGutterLOvProviderModifiedLines.BufferChanged(Sender: TObject);
begin
  TSynEditStringList(Sender).RemoveHanlders(self);
  TSynEditStringList(TextBuffer).AddModifiedHandler(senrLinesModified, @LineModified);
  TSynEditStringList(TextBuffer).AddGenericHandler(senrTextBufferChanged, TMethod(@BufferChanged));
end;

procedure TSynGutterLOvProviderModifiedLines.LineModified(Sender: TSynEditStrings; aIndex,
  aNewCount, aOldCount: Integer);
begin
  if (FFirstTextLineChanged < 0) or (AIndex + 1 < FFirstTextLineChanged) then
    FFirstTextLineChanged := AIndex + 1;

  if aOldCount = aNewCount then
    aIndex := aIndex + aOldCount
  else
    aIndex := TextBuffer.Count;
  if (FLastTextLineChanged <> 0) and (AIndex + 1 > FLastTextLineChanged) then
    FLastTextLineChanged := AIndex + 1;

  InvalidateTextLines(FFirstTextLineChanged, FLastTextLineChanged);
end;

procedure TSynGutterLOvProviderModifiedLines.SynStatusChanged(Sender: TObject;
  Changes: TSynStatusChanges);
begin
  if (scModified in Changes) and not TCustomSynEdit(SynEdit).Modified then begin;
    FFirstTextLineChanged := 1;
    FLastTextLineChanged := 0; // open end
    InvalidateTextLines(FFirstTextLineChanged, TextBuffer.Count);
  end;
end;

constructor TSynGutterLOvProviderModifiedLines.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  TSynEditStringList(TextBuffer).AddModifiedHandler(senrLinesModified, @LineModified);
  TSynEditStringList(TextBuffer).AddGenericHandler(senrTextBufferChanged, TMethod(@BufferChanged));
  TCustomSynEdit(SynEdit).RegisterStatusChangedHandler(@SynStatusChanged, [scModified]);
  FFirstTextLineChanged := -1;
  FLastTextLineChanged := -1;
  Color := clYellow;
  ColorSaved := clGreen;
end;

destructor TSynGutterLOvProviderModifiedLines.Destroy;
begin
  TSynEditStringList(TextBuffer).RemoveHanlders(self);
  TCustomSynEdit(SynEdit).UnRegisterStatusChangedHandler(@SynStatusChanged);
  inherited Destroy;
end;

{ TSynGutterLOvProviderBookmarks }

procedure TSynGutterLOvProviderBookmarks.DoMarkChange(Sender: TSynEditMark;
  Changes: TSynEditMarkChangeReasons);
var
  i: Integer;
  c: TColor;
  p: Integer;
begin
  if (smcrAdded in Changes) or
     ( (smcrVisible in Changes) and Sender.Visible )
  then begin
    if Sender.Visible then
      CreateGutterMark(Sender);
    InvalidateTextLines(0, TextBuffer.Count); // Todo
  end
  else
  if (smcrRemoved in Changes) or
     ( (smcrVisible in Changes) and not Sender.Visible )
  then begin
    i := IndexOfSynMark(Sender);
    if i >= 0 then begin
      FMarkList[i].Destroy;
      FMarkList.Delete(i);
    end;
    InvalidateTextLines(0, TextBuffer.Count); // Todo
  end
  else
  if (smcrLine in Changes) then begin
    i := IndexOfSynMark(Sender);
    if i >= 0 then begin
      FMarkList[i].FLine := Sender.Line;
      FMarkList[i].DoChange;
    end;
    FMarkList.ReSort;
    InvalidateTextLines(0, TextBuffer.Count); // Todo
  end
  else
  begin
    i := IndexOfSynMark(Sender);
    if i >= 0 then begin
      c := Color;
      p := Priority;
      AdjustColorForMark(Sender, c, p);
      FMarkList[i].FPriority := p;
      FMarkList[i].FColor    := c;
      FMarkList[i].DoChange;
    end;
    InvalidateTextLines(0, TextBuffer.Count); // Todo
  end
end;

procedure TSynGutterLOvProviderBookmarks.AdjustColorForMark(AMark: TSynEditMark;
  var AColor: TColor; var APriority: Integer);
begin
  if assigned(FOnColorForMark) then
    FOnColorForMark(Self, AMark, AColor, APriority);
end;

function TSynGutterLOvProviderBookmarks.CreateGutterMark(ASynMark: TSynEditMark): TSynGutterLOvMark;
var
  c: TColor;
  p: Integer;
begin
  Result := TSynGutterLOvMark.Create;
  Result.FData     := ASynMark;
  Result.FLine     := ASynMark.Line;
  Result.FColumn   := ASynMark.Column;
  c := Color;
  p := Priority;
  AdjustColorForMark(ASynMark, c, p);
  Result.FPriority := p;
  Result.FColor    := c;
  FMarkList.Add(Result);
  GutterPart.AddMark(Result);
end;

function TSynGutterLOvProviderBookmarks.IndexOfSynMark(ASynMark: TSynEditMark): Integer;
begin
  Result := FMarkList.Count - 1;
  while  Result >= 0 do begin;
    if FMarkList[Result].FData = Pointer(ASynMark) then exit;
    dec(Result);

  end;
end;

procedure TSynGutterLOvProviderBookmarks.BufferChanging(Sender: TObject);
begin
  TCustomSynEdit(SynEdit).Marks.UnRegisterChangeHandler(@DoMarkChange);
end;

procedure TSynGutterLOvProviderBookmarks.BufferChanged(Sender: TObject);
var
  i: Integer;
begin
  TSynEditStringList(Sender).RemoveHanlders(self);
  TSynEditStringList(TextBuffer).AddGenericHandler(senrTextBufferChanging, TMethod(@BufferChanging));
  TSynEditStringList(TextBuffer).AddGenericHandler(senrTextBufferChanged, TMethod(@BufferChanged));
  TCustomSynEdit(SynEdit).Marks.RegisterChangeHandler(@DoMarkChange,
    [smcrAdded, smcrRemoved, smcrLine, smcrVisible, smcrChanged]);

  while FMarkList.Count > 0 do begin
    FMarkList[0].Destroy;
    FMarkList.Delete(0);
  end;

  for i := 0 to TCustomSynEdit(SynEdit).Marks.Count - 1 do
    if TCustomSynEdit(SynEdit).Marks[i].Visible then
      CreateGutterMark(TCustomSynEdit(SynEdit).Marks[i]);
end;

constructor TSynGutterLOvProviderBookmarks.Create(AOwner: TComponent);
var
  i: Integer;
begin
  inherited Create(AOwner);
  Color := clBlue;
  TSynEditStringList(TextBuffer).AddGenericHandler(senrTextBufferChanging, TMethod(@BufferChanging));
  TSynEditStringList(TextBuffer).AddGenericHandler(senrTextBufferChanged, TMethod(@BufferChanged));

  TCustomSynEdit(SynEdit).Marks.RegisterChangeHandler(@DoMarkChange,
    [smcrAdded, smcrRemoved, smcrLine, smcrVisible, smcrChanged]);

  for i := 0 to TCustomSynEdit(SynEdit).Marks.Count - 1 do
    if TCustomSynEdit(SynEdit).Marks[i].Visible then
      CreateGutterMark(TCustomSynEdit(SynEdit).Marks[i]);
end;

destructor TSynGutterLOvProviderBookmarks.Destroy;
begin
  TSynEditStringList(TextBuffer).RemoveHanlders(self);
  TCustomSynEdit(SynEdit).Marks.UnRegisterChangeHandler(@DoMarkChange);
  inherited Destroy;
end;

{ TSynChildWinControl }

constructor TSynChildWinControl.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  BorderStyle := bsNone;
  if AOwner is TWinControl then
    DoubleBuffered := TWinControl(AOwner).DoubleBuffered;
end;

{ TSynGutterLineOverview }

procedure TSynGutterLineOverview.Init;
begin
  inherited Init;
  TSynEditStringList(TextBuffer).AddGenericHandler(senrLineCount, TMethod(@LineCountChanged));
  TSynEditStringList(TextBuffer).AddGenericHandler(senrTextBufferChanged, TMethod(@BufferChanged));
  FWinControl := TSynChildWinControl.Create(Self);
  FWinControl.Parent := SynEdit;
  FWinControl.DoubleBuffered := SynEdit.DoubleBuffered;
  FWinControl.OnPaint := @PaintWinControl;

  FLineMarks := TSynGutterLOvLineMarksList.Create;
  FProviders := TSynGutterLineOverviewProviderList.Create(Self);
  MarkupInfo.Background := $E0E0E0;

  DoResize(Self);
  LineCountchanged(nil, 0, 0);
end;

destructor TSynGutterLineOverview.Destroy;
begin
  Application.RemoveAsyncCalls(Self);
  TSynEditStringList(TextBuffer).RemoveHanlders(self);
  FreeAndNil(FProviders);
  FreeAndNil(FWinControl);
  FreeAndNil(FLineMarks);
  inherited Destroy;
end;

procedure TSynGutterLineOverview.LineCountChanged(Sender: TSynEditStrings; AIndex,
  ACount: Integer);
begin
  FLineMarks.TextLineCount := TextBuffer.Count;
  if (not SynEdit.HandleAllocated) or (not Self.Visible) then exit;
  ScheduleASync([losLineCountChanged]);
end;

procedure TSynGutterLineOverview.BufferChanged(Sender: TObject);
begin
  TSynEditStringList(Sender).RemoveHanlders(self);
  TSynEditStringList(TextBuffer).AddGenericHandler(senrLineCount, TMethod(@LineCountChanged));
  TSynEditStringList(TextBuffer).AddGenericHandler(senrTextBufferChanged, TMethod(@BufferChanged));
  LineCountChanged(nil, 0, 0);
end;

procedure TSynGutterLineOverview.SetVisible(const AValue: boolean);
begin
  inherited SetVisible(AValue);
  FWinControl.Visible := Visible and Gutter.Visible;
  if FWinControl.Visible then
    ScheduleASync([losResized, losLineCountChanged]);
end;

procedure TSynGutterLineOverview.GutterVisibilityChanged;
begin
  inherited GutterVisibilityChanged;
  FWinControl.Visible := Visible and Gutter.Visible;
  if FWinControl.Visible then
    ScheduleASync([losResized, losLineCountChanged]);
end;

procedure TSynGutterLineOverview.DoChange(Sender: TObject);
begin
  inherited;
  FWinControl.Invalidate;
end;

procedure TSynGutterLineOverview.InvalidateTextLines(AFromLine, AToLine: Integer);
begin
  InvalidatePixelLines(TextLineToPixel(AFromLine), TextLineToPixelEnd(AToLine));
end;

procedure TSynGutterLineOverview.InvalidatePixelLines(AFromLine, AToLine: Integer);
var
  r: TRect;
begin
  if not SynEdit.HandleAllocated then exit;
  r := Rect(0, Top, Width, Top + Height);
  r.Top := AFromLine;
  r.Bottom := AToLine + 1;
  InvalidateRect(FWinControl.Handle, @r, False);
end;

function TSynGutterLineOverview.TextLineToPixel(ALine: Integer): Integer;
var
  c: Integer;
begin
  if ALine < 0 then exit(-1);
  c := Max(1, TextBuffer.Count);
  if c = 0 then
    Result := -1
  else
    Result := Int64(ALine - 1) * Int64(Height) div c;
end;

function TSynGutterLineOverview.TextLineToPixelEnd(ALine: Integer): Integer;
var
  c, n: Integer;
begin
  if ALine < 0 then exit(-1);
  c := Max(1, TextBuffer.Count);
  if c = 0 then
    Result := -1
  else begin
    Result := (Int64(ALine - 1) * Int64(Height)) div c;
    n      := (Int64(ALine)     * Int64(Height)) div c - 1; // next line - 1 pix
    if n > Result then
      Result := n;
  end;
end;

procedure TSynGutterLineOverview.DoResize(Sender: TObject);
var
  i: Integer;
begin
  inherited DoResize(Sender);
  if (not SynEdit.HandleAllocated) or (not Self.Visible) then exit;
  FWinControl.BoundsRect := Bounds(Left,Top,Width,Height);

  {$IFDEF DARWIN}
  FLineMarks.PixelHeight := Height;
  for i := 0 to FProviders.Count - 1 do
    FProviders[i].Height := Height;
  FWinControl.Invalidate;
  {$ELSE}
  ScheduleASync([losResized]); // May only be executed after mouse up
  if not (losWaitForPaint in FState) then begin
    FLineMarks.PixelHeight := Height;
    for i := 0 to FProviders.Count - 1 do
      FProviders[i].Height := Height;
    FWinControl.Invalidate;
    FState := FState + [losWaitForPaint];
  end;
  {$ENDIF}
end;

procedure TSynGutterLineOverview.PaintWinControl(Sender: TObject);
var
  i: Integer;
  AClip: TRect;
begin
  FState := FState - [losWaitForPaint];
  if not Visible then exit;
  AClip := FWinControl.Canvas.ClipRect;
  AClip.Left := 0;
  AClip.Right := Width;
  FWinControl.Canvas.Brush.Color := MarkupInfo.Background;
  FWinControl.Canvas.FillRect(AClip);

  for i := 0 to Providers.Count - 1 do
    Providers[i].Paint(FWinControl.Canvas, AClip, 0);

  for i := 0 to FLineMarks.Count - 1 do
    FLineMarks[i].Paint(FWinControl.Canvas, AClip, 0, MarkHeight);
end;

function TSynGutterLineOverview.GetMarkHeight: Integer;
begin
  Result := FLineMarks.ItemHeight;
end;

procedure TSynGutterLineOverview.SetMarkHeight(const AValue: Integer);
begin
  FLineMarks.ItemHeight := AValue;
end;

procedure TSynGutterLineOverview.ScheduleASync(AStates: TSynGutterLOvStateFlags);
begin
  if not (losASyncScheduled in FState) then
    Application.QueueAsyncCall(@ExecASync, 0);
  FState := FState + [losASyncScheduled] + AStates;
end;

procedure TSynGutterLineOverview.ExecASync(Data: PtrInt);
var
  i: Integer;
begin
  if losLineCountChanged in FState then begin
    for i := 0 to FProviders.Count - 1 do
      FProviders[i].ReCalc;
    FLineMarks.ReBuild;
  end;

  if losResized in FState then begin
    FLineMarks.PixelHeight := Height;

    for i := 0 to FProviders.Count - 1 do
      FProviders[i].Height := Height;
  end;

  FWinControl.Invalidate;
  FState := FState - [losASyncScheduled, losResized, losLineCountChanged];
end;

function TSynGutterLineOverview.PreferedWidth: Integer;
begin
  Result := 10;
end;

procedure TSynGutterLineOverview.Assign(Source : TPersistent);
begin
  if Assigned(Source) and (Source is TSynGutterLineOverview) then
  begin
    inherited;
    // Todo: assign providerlist?
  end;
  inherited;
end;

procedure TSynGutterLineOverview.Paint(Canvas : TCanvas; AClip : TRect; FirstLine, LastLine : integer);
begin
  // do nothing
end;

procedure TSynGutterLineOverview.AddMark(AMark: TSynGutterLOvMark);
begin
  FLineMarks.AddMark(AMark);
end;

end.