* fulltext search demo by Reinier Olislagers, mantis #26863

git-svn-id: trunk@28884 -

.gitattributes

@@ -1209,6 +1209,7 @@ packages/cdrom/src/wnaspi32.pp svneol=native#text/plain
 packages/chm/Makefile svneol=native#text/plain
 packages/chm/Makefile.fpc svneol=native#text/plain
 packages/chm/Makefile.fpc.fpcmake svneol=native#text/plain
+packages/chm/examples/chmsearch.lpr svneol=native#text/plain
 packages/chm/fpmake.pp svneol=native#text/plain
 packages/chm/src/chmbase.pas svneol=native#text/plain
 packages/chm/src/chmcmd.lpi svneol=native#text/plain

packages/chm/examples/chmsearch.lpr

@@ -0,0 +1,178 @@
+program chmsearch;
+{ Fulltext search demo by Reinier Olislagers}
+{$mode objfpc}{$H+}
+
+uses
+  Classes, SysUtils, ChmReader, chmfiftimain;
+
+
+type
+  TChmWLCTopic = record
+    TopicIndex: DWord;
+    LocationCodes: array of DWord;
+  end;
+
+  TChmWLCTopicArray = array of TChmWLCTopic;
+
+procedure DoSearch(CHMFileName: string; Keyword: string);
+type
+  TTopicEntry = record
+    Topic:Integer;
+    Hits: Integer;
+    TitleHits: Integer;
+    FoundForThisRound: Boolean;
+  end;
+  TFoundTopics = array of TTopicEntry;
+var
+  FoundTopics: TFoundTopics;
+
+  procedure DeleteTopic(ATopicIndex: Integer);
+  var
+    MoveSize: DWord;
+  begin
+    WriteLn('Deleting Topic');
+    if ATopicIndex < High(FoundTopics) then
+    begin
+      MoveSize := SizeOf(TTopicEntry) * (High(FoundTopics) - (ATopicIndex+1));
+      Move(FoundTopics[ATopicIndex+1], FoundTopics[ATopicIndex], MoveSize);
+    end;
+    SetLength(FoundTopics, Length(FoundTopics) -1);
+  end;
+
+  function GetTopicIndex(ATopicID: Integer): Integer;
+  var
+    i: Integer;
+  begin
+    Result := -1;
+    for i := 0 to High(FoundTopics) do
+    begin
+      if FoundTopics[i].Topic = ATopicID then
+        Exit(i);
+    end;
+  end;
+
+  procedure UpdateTopic(TopicID: Integer; NewHits: Integer; NewTitleHits: Integer; AddNewTopic: Boolean);
+  var
+    TopicIndex: Integer;
+  begin
+    //WriteLn('Updating topic');
+    TopicIndex := GetTopicIndex(TopicID);
+    if TopicIndex = -1 then
+    begin
+      if AddNewTopic = False then
+        Exit;
+      SetLength(FoundTopics, Length(FoundTopics)+1);
+      TopicIndex := High(FoundTopics);
+      FoundTopics[TopicIndex].Topic := TopicID;
+    end;
+
+    FoundTopics[TopicIndex].FoundForThisRound := True;
+    if NewHits > 0 then
+      Inc(FoundTopics[TopicIndex].Hits, NewHits);
+    if NewTitleHits > 0 then
+      Inc(FoundTopics[TopicIndex].TitleHits, NewTitleHits);
+  end;
+
+var
+  CHMRead: TCHMReader;
+  CHMStream: TFileStream;
+  TopicResults: chmfiftimain.TChmWLCTopicArray;
+  TitleResults: chmfiftimain.TChmWLCTopicArray;
+  FIftiMainStream: TMemoryStream;
+  SearchReader: TChmSearchReader;
+  DocTitle: String;
+  DocURL: String;
+  CurrTopic: Integer;
+  k: Integer;
+
+begin
+  CHMStream := TFileStream.Create(CHMFileName, fmOpenRead or fmShareDenyWrite);
+  ChmRead := TChmReader.Create(CHMStream,false);
+  try
+    FIftiMainStream := CHMRead.GetObject('/$FIftiMain');
+    if FIftiMainStream = nil then
+    begin
+      writeln('Could not assign fiftimainstream. Aborting.');
+      halt(3);
+    end;
+    SearchReader := TChmSearchReader.Create(FIftiMainStream, True); //frees the stream when done
+    CHMRead.SearchReader := SearchReader;
+    TopicResults := SearchReader.LookupWord(Keyword, TitleResults);
+    //TopicResults := SearchReader.LookupWord(SearchWords[CurrTopic], TitleResults);
+    // Body results
+    for k := 0 to High(TopicResults) do
+    begin
+      UpdateTopic(TopicResults[k].TopicIndex, High(TopicResults[k].LocationCodes), 0, CurrTopic = 0);
+      writeln('Updated topic body with index '+inttostr(TopicResults[k].TopicIndex));
+    end;
+    // Title results
+    for k := 0 to High(TitleResults) do
+    begin
+      UpdateTopic(TitleResults[k].TopicIndex, 0, High(TitleResults[k].LocationCodes), CurrTopic = 0);
+      writeln('Updated title topic with index '+inttostr(TitleResults[k].TopicIndex));
+    end;
+
+    // Remove documents that don't have results
+    k := 0;
+    writeln('Going to remove docs without results; count: '+Inttostr(Length(FoundTopics)));
+    while k <= High(FoundTopics) do
+    begin
+      if FoundTopics[k].FoundForThisRound = False then
+        DeleteTopic(k)
+      else
+      begin
+        FoundTopics[k].FoundForThisRound := False;
+        Inc(k);
+      end;
+    end;
+
+    // Clear out results that don't contain all the words we are looking for
+    // Now lookup titles and urls to add to final search results
+    writeln('Found '+inttostr(Length(FoundTopics))+' topics');
+    for CurrTopic := 0 to High(FoundTopics) do
+    begin
+      try
+        DocURL := CHMRead.LookupTopicByID(FoundTopics[CurrTopic].Topic, DocTitle);
+        if (Length(DocURL) > 0) and (DocURL[1] <> '/') then
+          Insert('/', DocURL, 1);
+        if DocTitle = '' then
+          DocTitle := 'untitled';
+        writeln('DocURL    : '+DocURL);
+        writeln('DocTitle  : '+DocTitle);
+      except
+        on E: Exception do
+        begin
+          WriteLn('Exception');
+          writeln(E.Message);
+        end;
+      end;
+    end;
+  finally
+    CHMRead.Free;
+    CHMStream.Free;
+    //SearchReader.Free; //apparently not needed?!?!
+  end;
+end;
+
+var
+  SearchFor: string;
+begin
+  if paramstr(1)='' then
+  begin
+    writeln('No .chm file specified.');
+    writeln('Substituting hardcoded value lcl.chm');
+  end;
+  writeln('Enter search keyword or blank to exit:');
+  readln(SearchFor);
+  while (trim(SearchFor)<>'') do
+  begin
+    if paramstr(1)='' then
+      DoSearch('lcl.chm',SearchFor)
+    else
+      DoSearch(paramstr(1),SearchFor);
+    writeln('Enter search keyword or blank to exit:');
+    readln(SearchFor);
+  end;
+end.
+
+