lazarus/components/synedit/syneditsearch.pp

{-------------------------------------------------------------------------------
The contents of this file are subject to the Mozilla Public License
Version 1.1 (the "License"); you may not use this file except in compliance
with the License. You may obtain a copy of the License at
http://www.mozilla.org/MPL/

Software distributed under the License is distributed on an "AS IS" basis,
WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
the specific language governing rights and limitations under the License.

The Original Code is: SynEditSearch.pas, released 2000-04-07.

The Original Code is based on the mwEditSearch.pas file from the mwEdit
component suite by Martin Waldenburg and other developers.
Portions created by Martin Waldenburg are Copyright 1999 Martin Waldenburg.
All Rights Reserved.

Contributors to the SynEdit project are listed in the Contributors.txt file.

Alternatively, the contents of this file may be used under the terms of the
GNU General Public License Version 2 or later (the "GPL"), in which case
the provisions of the GPL are applicable instead of those above.
If you wish to allow use of your version of this file only under the terms
of the GPL and not to allow others to use your version of this file
under the MPL, indicate your decision by deleting the provisions above and
replace them with the notice and other provisions required by the GPL.
If you do not delete the provisions above, a recipient may use your version
of this file under either the MPL or the GPL.

$Id$

You may retrieve the latest version of this file at the SynEdit home page,
located at http://SynEdit.SourceForge.net

Known Issues:
-------------------------------------------------------------------------------}

unit SynEditSearch;

{$I synedit.inc}

interface

uses
  Classes
  {$IFDEF SYN_LAZARUS}, SynRegExpr{$ENDIF};

procedure MakeCompTable(Sensitive: boolean);
procedure MakeDelimiterTable;

type
  {$IFDEF SYN_LAZARUS}
  TSynEditSearchResult = class
  public
    Start: integer;
    Len: integer;
    Replace: string;
    constructor Create(NewStart, NewLen: integer; const NewReplace: string);
  end;
  {$ENDIF}

  TSynEditSearch = class(TObject)
  private
    Run: PChar;
    Origin: PChar;
    TheEnd: PChar;
    Pat: string;
    fCount: Integer;
    fTextLen: Integer;
    Look_At: Integer;
    PatLen, PatLenPlus: Integer;
    Shift: array[0..255] of Integer;
    fSensitive: Boolean;
    fWhole: Boolean;
    fResults: TList;
    fShiftInitialized: boolean;
    {$IFDEF SYN_LAZARUS}
    FoundLen: integer;
    RegExprEngine : TRegExpr;
    fRegExpr: Boolean;
    fRegExprSingleLine: boolean;
    fRegExprReplace: string;
    fReplacement: string;
    function GetResultLen(Index: integer): integer;
    procedure SetRegExpr(const NewValue: boolean);
    {$ENDIF}
    function GetFinished: Boolean;
    function GetResult(Index: integer): integer;
    function GetResultCount: integer;
    procedure InitShiftTable;
    procedure SetPattern(const Value: string);
    procedure SetSensitive(const Value: Boolean);
  protected
    function TestWholeWord: boolean; virtual;
  public
    constructor Create;
    destructor Destroy; override;
    function FindAll(const NewText: string): integer;
    function FindFirst(const NewText: string): Integer;
    procedure FixResults(First, Delta: integer);
    function Next: Integer;
    property Count: Integer read fCount write fCount;
    property Finished: Boolean read GetFinished;
    property Pattern: string read Pat write SetPattern;
    property Results[Index: integer]: integer read GetResult;
    property ResultCount: integer read GetResultCount;
    property Sensitive: Boolean read fSensitive write SetSensitive;
    property Whole: Boolean read fWhole write fWhole;
    {$IFDEF SYN_LAZARUS}
  public
    procedure ClearResults;
    function GetReplace(Index: integer): string;
    property RegularExpressions: Boolean read fRegExpr write SetRegExpr;
    property ResultLengths[Index: integer]: integer read GetResultLen;
    property RegExprSingleLine: Boolean 
        read fRegExprSingleLine write fRegExprSingleLine;
    property RegExprReplace: string
        read fRegExprReplace write fRegExprReplace;
    property Replacement: string read fReplacement write fReplacement;
    {$ENDIF}
  end;

implementation

uses
  {$IFDEF SYN_LAZARUS}
  LCLIntf, LCLType,
  {$ELSE}
  Windows,
  {$ENDIF}
  SysUtils;
  
var
  CompTableSensitive: boolean;
  CompTable: array[#0..#255] of Byte;
  DelimTable: array[#0..#255] of boolean;

procedure MakeCompTable(Sensitive: Boolean);
var
  I: Char;
begin
  if CompTableSensitive <> Sensitive then
  begin
    CompTableSensitive := Sensitive;
    {$IFDEF FPC}
    if Sensitive then
      for I := #0 to #255 do CompTable[I] := ord(I)
    else
      for I := #0 to #255 do CompTable[I] := ord(uppercase(I)[1]);
    {$ELSE}
    for I := #0 to #255 do CompTable[I] := ord(I);
    if not Sensitive then CharLowerBuff(PChar(@CompTable[#0]), 256);
    {$ENDIF}
  end;
end;

procedure MakeDelimiterTable;
var
  c: char;
begin
  for c := #0 to #255 do DelimTable[c] := not IsCharAlphaNumeric(c);
end;

{ TSynEditSearch }

constructor TSynEditSearch.Create;
begin
  inherited Create;
  fResults := TList.Create;
  {$IFDEF SYN_LAZARUS}
  fRegExpr:=false;
  fRegExprSingleLine:=true;
  RegExprEngine:=TRegExpr.Create;
  FoundLen:=0;
  {$ENDIF}
end;

function TSynEditSearch.GetFinished: Boolean;
begin
  Result := (Run >= TheEnd) or (PatLen >= fTextLen);
end;

function TSynEditSearch.GetResult(Index: integer): integer;
begin
  Result := 0;
  if (Index >= 0) and (Index < fResults.Count) then
    {$IFDEF SYN_LAZARUS}
    Result := TSynEditSearchResult(fResults[Index]).Start;
    {$ELSE}
    Result := integer(fResults[Index]);
    {$ENDIF}
end;

function TSynEditSearch.GetResultCount: integer;
begin
  Result := fResults.Count;
end;

procedure TSynEditSearch.FixResults(First, Delta: integer);
var
  i: integer;
begin
  if (Delta <> 0) and (fResults.Count > 0) then begin
    i := Pred(fResults.Count);
    while i >= 0 do begin
      {$IFDEF SYN_LAZARUS}
      if GetResult(i)>=First then begin
        dec(TSynEditSearchResult(fResults[i]).Start,Delta);
        if GetResult(i)<First then begin
          // search result overlaps with deletion -> delete this result
          TSynEditSearchResult(fResults[i]).Free;
          fResults.Delete(i);
        end;
      end;
      {$ELSE}
      if GetResult(i) <= First then break;
      fResults[i] := pointer(integer(fResults[i]) - Delta);
      {$ENDIF}
      Dec(i);
    end;
  end;
end;

procedure TSynEditSearch.InitShiftTable;
var
  I: Byte;
begin
  PatLen := Length(Pat);
  if Patlen = 0 then raise Exception.Create('Pattern is empty');
  PatLenPlus := PatLen + 1;
  Look_At := 1;
  for I := 0 to 255 do Shift[I] := PatLenPlus;
  for I := 1 to PatLen do Shift[CompTable[Pat[i]]] := PatLenPlus - I;
  while Look_at < PatLen do
  begin
    if CompTable[Pat[PatLen]] = CompTable[Pat[PatLen - (Look_at)]] then exit;
    inc(Look_at);
  end;
  fShiftInitialized := TRUE;
end;

function TSynEditSearch.TestWholeWord: boolean;
var
  Test: PChar;
begin
  Test := Run - PatLen;
  Result := ((Test < Origin) or DelimTable[Test[0]]) and
    ((Run >= TheEnd) or DelimTable[Run[1]]);
end;

function TSynEditSearch.Next: Integer;
var
  I: Integer;
  J: PChar;
begin
  Result := 0;
  {$IFDEF SYN_LAZARUS}
  if not fRegExpr then begin
  {$ENDIF}
    inc(Run, PatLen);
    FoundLen:=PatLen;
    while Run < TheEnd do
    begin
      if CompTable[Pat[Patlen]] <> CompTable[Run^] then
        inc(Run, Shift[CompTable[(Run + 1)^]])
      else
      begin
        J := Run - PatLen + 1;
        I := 1;
        while CompTable[Pat[I]] = CompTable[J^] do
        begin
          if I = PatLen then
          begin
            Case fWhole of
              True: if not TestWholeWord then break;
            end;
            inc(fCount);
            Result := Run - Origin - Patlen + 2;
            exit;
          end;
          inc(I);
          inc(J);
        end;
{begin}                                                                         //mh 2000-08-29
//        inc(Run, Look_At + Shift[CompTable[(Run + Look_at)^]] - 1);
        Inc(Run, Look_At);
        if Run >= TheEnd then
          break;
        Inc(Run, Shift[CompTable[Run^]] - 1);
{end}                                                                           //mh 2000-08-29
      end;
    end;
  {$IFDEF SYN_LAZARUS}
  end else begin
    // regular expressions
    inc(Run);
    if RegExprEngine.ExecPos(Run-Origin+1) then begin
      Result:=RegExprEngine.MatchPos[0];
      FoundLen:=RegExprEngine.MatchLen[0];
      Run:=Origin+Result-1;
    end else begin
      Result:=0;
      FoundLen:=0;
      Run:=TheEnd;
    end;
  {$ENDIF}
  end;
end;

destructor TSynEditSearch.Destroy;
begin
  {$IFDEF SYN_LAZARUS}
  ClearResults;
  RegExprEngine.Free;
  {$ENDIF}
  fResults.Free;
  inherited Destroy;
end;

procedure TSynEditSearch.SetPattern(const Value: string);
begin
  if Pat <> Value then begin
    Pat := Value;
    fShiftInitialized := FALSE;                                  
    {$IFDEF SYN_LAZARUS}
    PatLen:=length(Pat);
    {$ENDIF}
  end;
  fCount := 0;
end;

procedure TSynEditSearch.SetSensitive(const Value: Boolean);
begin
  if fSensitive <> Value then begin
    fSensitive := Value;
    MakeCompTable(Value);
    fShiftInitialized := FALSE;
    {$IFDEF SYN_LAZARUS}
    RegExprEngine.ModifierI:=not fSensitive;
    {$ENDIF}
  end;
end;

function TSynEditSearch.FindAll(const NewText: string): integer;
var
  Found: integer;
  {$IFDEF SYN_LAZARUS}
  TheReplace: string;
  {$ENDIF}
begin
  if not fShiftInitialized then
    InitShiftTable;
  {$IFDEF SYN_LAZARUS}
  ClearResults;
  {$ELSE}
  // never shrink Capacity
  fResults.Count := 0;
  {$ENDIF}
  Found := FindFirst(NewText);
  while Found > 0 do
  begin
    {$IFDEF SYN_LAZARUS}
    TheReplace:=Replacement;
    if fRegExpr then
      TheReplace:=RegExprEngine.Substitute(Replacement);
    fResults.Add(TSynEditSearchResult.Create(Found,FoundLen,TheReplace));
    {$ELSE}
    fResults.Add(pointer(Found));
    {$ENDIF}
    Found := Next;
  end;
  Result := fResults.Count;
end;

function TSynEditSearch.FindFirst(const NewText: string): Integer;
begin
  Result := 0;
  fTextLen := Length(NewText);
  if fTextLen=0 then exit;
  {$IFDEF SYN_LAZARUS}
  if fRegExpr then begin
    RegExprEngine.ModifierI:=not fSensitive;
    RegExprEngine.ModifierM:=not fRegExprSingleLine;
    RegExprEngine.Expression:=Pat;
    RegExprEngine.InputString:=NewText;
  end;
  {$ENDIF}
  if (fTextLen >= PatLen) or fRegExpr then
  begin
    Origin := PChar(NewText);
    TheEnd := Origin + fTextLen;
    Run := (Origin - 1);
    Result := Next;
  end;
end;

{$IFDEF SYN_LAZARUS}
procedure TSynEditSearch.ClearResults;
var
  i: Integer;
begin
  for i:=0 to fResults.Count-1 do
    TSynEditSearchResult(fResults[i]).Free;
  fResults.Clear;
end;

function TSynEditSearch.GetReplace(Index: integer): string;
begin
  if (Index >= 0) and (Index < fResults.Count) then
    Result := TSynEditSearchResult(fResults[Index]).Replace
  else
    Result := Replacement;
end;

function TSynEditSearch.GetResultLen(Index: integer): integer;
begin
  if (Index>=0) and (Index<fResults.Count) then
    Result := TSynEditSearchResult(fResults[Index]).Len
  else
    Result:=FoundLen;
end;

procedure TSynEditSearch.SetRegExpr(const NewValue: boolean);
begin
  if NewValue=fRegExpr then exit;
  fRegExpr:=NewValue;
end;


{ TSynEditSearchResult }

constructor TSynEditSearchResult.Create(NewStart, NewLen: integer;
  const NewReplace: string);
begin
  Start:=NewStart;
  Len:=NewLen;
  Replace:=NewReplace;
end;

{$ENDIF}

initialization
  CompTableSensitive := True; // force the table initialization
  MakeCompTable(False);
  MakeDelimiterTable;
  
end.