From d5f2adb382bce679c7b8962a6c0a7197fa7b1fe2 Mon Sep 17 00:00:00 2001
From: skalogryz <skalogryz@8e941d3f-bd1b-0410-a28a-d453659cc2b4>
Date: Thu, 24 Mar 2016 12:56:23 +0000
Subject: [PATCH] richmemo: default search engine

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@4587 8e941d3f-bd1b-0410-a28a-d453659cc2b4
---
 components/richmemo/wsrichmemo.pas | 60 ++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

diff --git a/components/richmemo/wsrichmemo.pas b/components/richmemo/wsrichmemo.pas
index 093d4c690..59003f4e7 100644
--- a/components/richmemo/wsrichmemo.pas
+++ b/components/richmemo/wsrichmemo.pas
@@ -294,7 +294,67 @@ end;
 
 class function TWSCustomRichMemo.Search(const AWinControl: TWinControl; const ANiddle: string;
   const SearchOpts: TIntSearchOpt): Integer;
+var
+  Hay    : UnicodeString;
+  Niddle : UnicodeString;
+  Hay8   : String;
+  isUnicode : Boolean;
+  i, se, ln : Integer;
+
 begin
+  if not Assigned(AWinControl) or not (AWinControl is TCustomRichMemo) then begin
+    Result:=-1;
+    Exit;
+  end;
+  if not GetTextLen(AWinControl, ln) then begin
+    Result:=-1;
+    Exit;
+  end;
+
+  isUnicode:=false;
+  if not GetSubText(AWinControl, 0, ln, true, isUnicode, Hay8, Hay) then begin
+    Result:=-1;
+    Exit;
+  end;
+  if not isUnicode then begin
+    Hay:=UTF8Decode(Hay8);
+    Hay8:='';
+  end;
+
+  if not (soMatchCase in SearchOpts.Options) then begin
+    Niddle:=WideLowerCase(UTF8Decode(ANiddle));
+    Hay:=WideLowercase(Hay);
+  end else
+    Niddle:=UTF8Decode(ANiddle);
+
+  i:=SearchOpts.start;
+  if i<=0 then i:=1 else inc(i);
+
+  if soBackward in SearchOpts.Options then begin
+    dec(i); // to allow repeatative search
+
+    se:=0;
+    if (SearchOpts.len>0) then se:=i-SearchOpts.len;
+    if se<=0 then se:=1;
+
+    for i:=i downto se do
+      //todo: unicode comparison is "a bit more" complex, than just memory comparison
+      if CompareMem(@Niddle[1], @Hay[i], length(Niddle)*2) then begin
+        Result:=i-1; // offset one character! since it should be cursor position
+        Exit;
+      end;
+  end else begin
+    se:=length(Hay)-length(Niddle);
+    if (SearchOpts.len>0) and (se-i>SearchOpts.len) then
+      se:=i+SearchOpts.len;
+
+    for i:=i to se do
+      //todo: unicode comparison is "a bit more" complex, than just memory comparison
+      if CompareMem(@Niddle[1], @Hay[i], length(Niddle)*2) then begin
+        Result:=i-1; // offset one character! since it should be cursor position
+        Exit;
+    end;
+  end;
   Result:=-1;
 end;