(*
    History++ plugin for Miranda IM: the free IM client for Microsoft* Windows*

    Copyright (C) 2006-2009 theMIROn, 2003-2006 Art Fedorov.
    History+ parts (C) 2001 Christian Kastner

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*)

{-----------------------------------------------------------------------------
 hpp_events (historypp project)

 Version:   1.5
 Created:   05.08.2004
 Author:    Oxygen

 [ Description ]

 Some refactoring we have here, so now all event reading
 routines are here. By event reading I mean getting usefull
 info out of DB and translating it into human words,
 like reading different types of messages and such.

 [ History ]

 1.5 (05.08.2004)
   First version

 [ Modifications ]
 none

 [ Known Issues ]
 none

 Contributors: theMIROn, Art Fedorov
-----------------------------------------------------------------------------}

unit hpp_events;

interface

uses
  Windows, SysUtils,
  m_api,
  hpp_global;

type
  PEventRecord = ^TEventRecord;
  TEventRecord = record
    Name : String;
    XML  : AnsiString;
    i    : SmallInt;
    iName: PAnsiChar;
    iSkin: SmallInt;
  end;

const
  EventRecords: array[TMessageType] of TEventRecord = (
    (Name:'Unknown';               XML:'';            i:-1; iSkin:-1),
    (Name:'Incoming events';       XML:'';            i:HPP_ICON_EVENT_INCOMING;  iName:'hppevn_inc';       iSkin:-1),
    (Name:'Outgoing events';       XML:'';            i:HPP_ICON_EVENT_OUTGOING;  iName:'hppevn_out';       iSkin:-1),
    (Name:'Message';               XML:'MSG';         i:HPP_SKIN_EVENT_MESSAGE;                             iSkin:SKINICON_EVENT_MESSAGE),
    (Name:'Link';                  XML:'URL';         i:HPP_SKIN_EVENT_URL;                                 iSkin:SKINICON_EVENT_URL),
    (Name:'File transfer';         XML:'FILE';        i:HPP_SKIN_EVENT_FILE;                                iSkin:SKINICON_EVENT_FILE),
    (Name:'System message';        XML:'SYS';         i:HPP_ICON_EVENT_SYSTEM;    iName:'hppevn_sys';       iSkin:-1),
    (Name:'Contacts';              XML:'ICQCNT';      i:HPP_ICON_EVENT_CONTACTS;  iName:'hppevn_icqcnt';    iSkin:-1),
    (Name:'Status changes';        XML:'STATUSCNG';   i:HPP_ICON_EVENT_STATUS;    iName:'hppevn_status';    iSkin:-1),
    (Name:'SMTP Simple Email';     XML:'SMTP';        i:HPP_ICON_EVENT_SMTPSIMPLE;iName:'hppevn_smtp';      iSkin:-1),
    (Name:'Other events (unknown)';XML:'OTHER';       i:HPP_SKIN_OTHER_MIRANDA;                             iSkin:SKINICON_OTHER_MIRANDA),
    (Name:'Nick changes';          XML:'NICKCNG';     i:HPP_ICON_EVENT_NICK;      iName:'hppevn_nick';      iSkin:-1),
    (Name:'Avatar changes';        XML:'AVACNG';      i:HPP_ICON_EVENT_AVATAR;    iName:'hppevn_avatar';    iSkin:-1),
    (Name:'WATrack notify';        XML:'WATRACK';     i:HPP_ICON_EVENT_WATRACK;   iName:'hppevn_watrack';   iSkin:-1),
    (Name:'Status message changes';XML:'STATUSMSGCHG';i:HPP_ICON_EVENT_STATUSMES; iName:'hppevn_statuschng';iSkin:-1),
    (Name:'Voice call';            XML:'VCALL';       i:HPP_ICON_EVENT_VOICECALL; iName:'hppevn_vcall';     iSkin:-1),
    (Name:'Custom';                XML:'';            i:-1; iSkin:-1)
  );

const
  EVENTTYPE_STATUSCHANGE        = 25368;  // from srmm's
  EVENTTYPE_SMTPSIMPLE          = 2350;   // from SMTP Simple
  EVENTTYPE_NICKNAMECHANGE      = 9001;   // from pescuma
  EVENTTYPE_STATUSMESSAGECHANGE = 9002;   // from pescuma
  EVENTTYPE_AVATARCHANGE        = 9003;   // from pescuma
  EVENTTYPE_CONTACTLEFTCHANNEL  = 9004;   // from pescuma
  EVENTTYPE_VOICE_CALL          = 8739;   // from pescuma

// Miranda timestamp to TDateTime
function TimestampToDateTime(const Timestamp: DWord): TDateTime;
function TimestampToString(const Timestamp: DWord): String;
// general routine
function ReadEvent(hDBEvent: THandle; UseCP: Cardinal = CP_ACP): THistoryItem;
function GetEventInfo(hDBEvent: THANDLE): TDBEventInfo;
function GetEventTimestamp(hDBEvent: THandle): DWord;
function GetEventMessageType(hDBEvent: THandle): TMessageTypes;
function GetEventDateTime(hDBEvent: THandle): TDateTime;
function GetEventRecord(const Hi: THistoryItem): PEventRecord;
function GetMessageType(EventInfo: TDBEventInfo; var EventIndex: Integer): TMessageTypes;
// global routines
function GetEventCoreText(EventInfo: TDBEventInfo; var Hi: THistoryItem): Boolean;
// specific routines
procedure GetEventTextForMessage(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForFile(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForUrl(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForAuthRequest(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForYouWereAdded(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForSms(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForContacts(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForStatusChange(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForAvatarChange(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForJabberChatStates(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextWATrackRequest(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextWATrackAnswer(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextWATrackError(EventInfo: TDBEventInfo; var Hi: THistoryItem);
procedure GetEventTextForOther(EventInfo: TDBEventInfo; var Hi: THistoryItem);

implementation

uses
  hpp_contacts, hpp_options;

{$include m_music.inc}

const // registered Jabber db event types (not public)
  JABBER_DB_EVENT_TYPE_CHATSTATES          = 2000;
//  JS_DB_GETEVENTTEXT_CHATSTATES            = '/GetEventText2000';
  JABBER_DB_EVENT_CHATSTATES_GONE          = 1;

type
  TModuleEventRecord = record
    EventDesc: PDBEVENTTYPEDESCR;
    EventRecord: TEventRecord;
  end;

  TTextFunction = procedure(EventInfo: TDBEventInfo; var Hi: THistoryItem);

  TEventTableItem = record
    EventType   : Word;
    MessageType : TMessageType;
    TextFunction: TTextFunction;
  end;

var
  EventTable: array[0..17] of TEventTableItem = (
    // must be the first item in array for unknown events
    (EventType: MaxWord;                         MessageType: mtOther;         TextFunction: GetEventTextForOther),
    // events definitions
    (EventType: EVENTTYPE_MESSAGE;               MessageType: mtMessage;       TextFunction: GetEventTextForMessage),
    (EventType: EVENTTYPE_URL;                   MessageType: mtUrl;           TextFunction: GetEventTextForUrl),
    (EventType: EVENTTYPE_FILE;                  MessageType: mtFile;          TextFunction: GetEventTextForFile),
    (EventType: EVENTTYPE_AUTHREQUEST;           MessageType: mtSystem;        TextFunction: GetEventTextForAuthRequest),
    (EventType: EVENTTYPE_ADDED;                 MessageType: mtSystem;        TextFunction: GetEventTextForYouWereAdded),
    (EventType: EVENTTYPE_CONTACTS;              MessageType: mtContacts;      TextFunction: GetEventTextForContacts),
    (EventType: EVENTTYPE_STATUSCHANGE;          MessageType: mtStatus;        TextFunction: GetEventTextForStatusChange),
    (EventType: EVENTTYPE_SMTPSIMPLE;            MessageType: mtSMTPSimple;    TextFunction: GetEventTextForMessage),
    (EventType: EVENTTYPE_NICKNAMECHANGE;        MessageType: mtNickChange;    TextFunction: GetEventTextForMessage),
    (EventType: EVENTTYPE_STATUSMESSAGECHANGE;   MessageType: mtStatusMessage; TextFunction: GetEventTextForMessage),
    (EventType: EVENTTYPE_AVATARCHANGE;          MessageType: mtAvatarChange;  TextFunction: GetEventTextForAvatarChange),
    (EventType: JABBER_DB_EVENT_TYPE_CHATSTATES; MessageType: mtStatus;        TextFunction: GetEventTextForJabberChatStates),
    (EventType: EVENTTYPE_CONTACTLEFTCHANNEL;    MessageType: mtStatus;        TextFunction: GetEventTextForMessage),
    (EventType: EVENTTYPE_WAT_REQUEST;           MessageType: mtWATrack;       TextFunction: GetEventTextWATrackRequest),
    (EventType: EVENTTYPE_WAT_ANSWER;            MessageType: mtWATrack;       TextFunction: GetEventTextWATrackAnswer),
    (EventType: EVENTTYPE_WAT_ERROR;             MessageType: mtWATrack;       TextFunction: GetEventTextWATrackError),
    (EventType: EVENTTYPE_VOICE_CALL;            MessageType: mtVoiceCall;     TextFunction: GetEventTextForMessage)
  );

var
  ModuleEventRecords: array of TModuleEventRecord;
  RecentEvent: THandle = 0;
  RecentEventInfo: TDBEventInfo;

var
  EventBuffer: THppBuffer;
  TextBuffer: THppBuffer;

const
  // 1970-01-01T00:00:00 in TDateTime
  UnixTimeStart = 25569;
  SecondsPerDay = 60*60*24;

// Miranda timestamp to TDateTime
function TimestampToDateTime(const Timestamp: DWord): TDateTime;
begin
  Result := UnixTimeStart + TimeZone_ToLocal(Timestamp) / SecondsPerDay;
end;

// should probably add function param to use
// custom grid options object and not the global one
function TimestampToString(const Timestamp: DWord): String;
begin
  Result := FormatDateTime(GridOptions.DateTimeFormat,TimestampToDateTime(Timestamp));
end;

function GetEventTimestamp(hDBEvent: THandle): DWord;
begin
  if RecentEvent <> hDBEvent then
  begin
    ZeroMemory(@RecentEventInfo, SizeOf(RecentEventInfo));
    RecentEventInfo.cbBlob := 0;
    db_event_get(hDBEvent, @RecentEventInfo);
    RecentEvent := hDBEvent;
  end;
  Result := RecentEventInfo.timestamp;
end;

function GetEventMessageType(hDBEvent: THandle): TMessageTypes;
var
  EventIndex: Integer;
begin
  if RecentEvent <> hDBEvent then
  begin
    ZeroMemory(@RecentEventInfo, SizeOf(RecentEventInfo));
    RecentEventInfo.cbBlob := 0;
    db_event_get(hDBEvent, @RecentEventInfo);
    RecentEvent := hDBEvent;
  end;
  Result := GetMessageType(RecentEventInfo,EventIndex);
end;

function GetEventDateTime(hDBEvent: THandle): TDateTime;
begin
  Result := TimestampToDateTime(GetEventTimestamp(hDBEvent));
end;

function GetEventRecord(const Hi: THistoryItem): PEventRecord;
var
  MesType: TMessageTypes;
  mt: TMessageType;
  etd: PDBEVENTTYPEDESCR;
  i,count: integer;
begin
  MesType := Hi.MessageType;
  exclude(MesType, mtIncoming);
  exclude(MesType, mtOutgoing);
  exclude(MesType, mtOther);
  for mt := Low(EventRecords) to High(EventRecords) do
  begin
    if mt in MesType then
    begin
      Result := @EventRecords[mt];
      exit;
    end;
  end;
  etd := DbEvent_GetType(PAnsiChar(Hi.Module), Hi.EventType);
  if etd = nil then
  begin
    Result := @EventRecords[mtOther];
    exit;
  end;
  count := Length(ModuleEventRecords);
  for i := 0 to count - 1 do
    if ModuleEventRecords[i].EventDesc = etd then
    begin
      Result := @ModuleEventRecords[i].EventRecord;
      exit;
    end;
  SetLength(ModuleEventRecords, count + 1);
  ModuleEventRecords[count].EventDesc := etd;
  ModuleEventRecords[count].EventRecord := EventRecords[mtOther];
  ModuleEventRecords[count].EventRecord.Name := AnsiToWideString(etd.descr, CP_ACP);
  Result := @ModuleEventRecords[count].EventRecord;
end;

function Utf8ToWideChar(Dest: PWideChar; MaxDestChars: Integer; Source: PAnsiChar; SourceBytes: Integer; CodePage: Cardinal = CP_ACP): Integer;
const
  MB_ERR_INVALID_CHARS = 8;
var
  Src,SrcEnd: PAnsiChar;
  Dst,DstEnd: PWideChar;
begin
  if (Source = nil) or (SourceBytes <= 0) then
  begin
    Result := 0;
  end
  else if (Dest = nil) or (MaxDestChars <= 0) then
  begin
    Result := -1;
  end
  else
  begin
    Src := Source;
    SrcEnd := Source + SourceBytes;
    Dst := Dest;
    DstEnd := Dst + MaxDestChars;
    while (PAnsiChar(Src) < PAnsiChar(SrcEnd)) and (Dst < DstEnd) do
    begin
      if (Byte(Src[0]) and $80) = 0 then
      begin
        Dst[0] := WideChar(Src[0]);
        Inc(Src);
      end
      else if (Byte(Src[0]) and $E0) = $E0 then
      begin
        if Src + 2 >= SrcEnd then
          break;
        if (Src[1] = #0) or ((Byte(Src[1]) and $C0) <> $80) then
          break;
        if (Src[2] = #0) or ((Byte(Src[2]) and $C0) <> $80) then
          break;
        Dst[0] := WideChar(((Byte(Src[0]) and $0F) shl 12) + ((Byte(Src[1]) and $3F) shl 6) +
          ((Byte(Src[2]) and $3F)));
        Inc(Src, 3);
      end
      else if (Byte(Src[0]) and $E0) = $C0 then
      begin
        if Src + 1 >= SrcEnd then
          break;
        if (Src[1] = #0) or ((Byte(Src[1]) and $C0) <> $80) then
          break;
        Dst[0] := WideChar(((Byte(Src[0]) and $1F) shl 6) + ((Byte(Src[1]) and $3F)));
        Inc(Src, 2);
      end
      else
      begin
        if MultiByteToWideChar(CodePage, MB_ERR_INVALID_CHARS, Src, 1, Dst, 1) = 0 then
          Dst[0] := '?';
        Inc(Src);
      end;
      Inc(Dst);
    end;
    Dst[0] := #0;
    Inc(Dst);
    Result := Dst - Dest;
  end;
end;

function TextHasUrls(var Text: String): Boolean;
var
  i,len,lenW: Integer;
  pText,pPos: PChar;
begin
  Result := False;
  len := Length(Text);
  if len=0 then exit;

  pText := PChar(Text);
  for i := 0 to High(UrlPrefix) do
  begin
    pPos := StrPos(pText, PChar(UrlPrefix[i]));
    if not Assigned(pPos) then
      continue;
    Result := ((uint_ptr(pPos) = uint_ptr(pText)) or not IsWideCharAlphaNumeric((pPos - 1)^)) and
      IsWideCharAlphaNumeric((pPos + Length(UrlPrefix[i]))^);
    if Result then
      exit;
  end;

  if not Assigned(StrPos(PChar(Text),':/')) then exit;

  lenW := (len+1)*SizeOf(Char);

  TextBuffer.Lock;
  TextBuffer.Allocate(lenW);
  Move(Text[1],TextBuffer.Buffer^,lenW);
  CharLowerBuffW(PChar(TextBuffer.Buffer),len);
  for i := 0 to High(UrlProto) do
  begin
    pPos := StrPos(PChar(TextBuffer.Buffer), PChar(UrlProto[i].proto));
    if not Assigned(pPos) then
      continue;
    Result := ((uint_ptr(pPos) = uint_ptr(TextBuffer.Buffer)) or
      not IsWideCharAlphaNumeric((pPos - 1)^));
    if Result then
      break;
  end;
  TextBuffer.Unlock;
end;

function GetEventInfo(hDBEvent: THANDLE): TDBEventInfo;
var
  BlobSize: integer;
begin
  ZeroMemory(@Result, SizeOf(Result));
  BlobSize := db_event_getBlobSize(hDBEvent);
  if BlobSize > 0 then
  begin
    EventBuffer.Allocate(BlobSize+2); // cheat, for possible crash avoid
    Result.pBlob := EventBuffer.Buffer;
  end
  else
    BlobSize := 0;

  Result.cbBlob := BlobSize;
  if db_event_get(hDBEvent, @Result) = 0 then
  begin
    Result.cbBlob := BlobSize;
    if BlobSize > 0 then
    begin
      PAnsiChar(Result.pBlob)[BlobSize  ]:=#0;
      PAnsiChar(Result.pBlob)[BlobSize+1]:=#0;
    end;
  end
  else
    Result.cbBlob := 0;
end;

function GetMessageType(EventInfo: TDBEventInfo; var EventIndex: Integer): TMessageTypes;
var
  i: Integer;
begin
  EventIndex := 0;
  for i := 1 to High(EventTable) do
    if EventTable[i].EventType = EventInfo.EventType then
    begin
      EventIndex := i;
      break;
    end;
  Result := [EventTable[EventIndex].MessageType];
  if (EventInfo.flags and DBEF_SENT) = 0 then
    include(Result, mtIncoming)
  else
    include(Result, mtOutgoing);
end;

// reads event from hDbEvent handle
// reads all THistoryItem fields
// *EXCEPT* Proto field. Fill it manually, plz
function ReadEvent(hDBEvent: THandle; UseCP: Cardinal = CP_ACP): THistoryItem;
var
  EventInfo: TDBEventInfo;
  EventIndex: integer;
  Handled: Boolean;
begin
  ZeroMemory(@Result,SizeOf(Result));
  Result.Height := -1;
  EventBuffer.Lock;
  EventInfo := GetEventInfo(hDBEvent);
  try
    Result.Module := EventInfo.szModule;
    Result.proto := '';
    Result.Time := EventInfo.Timestamp;
    Result.EventType := EventInfo.EventType;
    Result.IsRead := Boolean(EventInfo.flags and DBEF_READ);
    // enable autoRTL feature
    if Boolean(EventInfo.flags and DBEF_RTL) then
      Result.RTLMode := hppRTLEnable;
    Result.MessageType := GetMessageType(EventInfo, EventIndex);
    Result.CodePage := UseCP;
    Handled := GetEventCoreText(EventInfo,Result);
    if not Handled then
      EventTable[EventIndex].TextFunction(EventInfo, Result);
    Result.Text := AdjustLineBreaks(Result.Text);
    Result.Text := TrimRight(Result.Text);
    if mtMessage in Result.MessageType then
      if TextHasUrls(Result.Text) then
      begin
        exclude(Result.MessageType, mtMessage);
        include(Result.MessageType, mtUrl);
      end;
  finally
    EventBuffer.Unlock;
  end;
end;

procedure ReadStringTillZeroA(Text: PAnsiChar; Size: LongWord; var Result: AnsiString; var Pos: LongWord);
begin
  while (Pos < Size) and ((Text+Pos)^ <> #0) do
  begin
    Result := Result + (Text+Pos)^;
    Inc(Pos);
  end;
  Inc(Pos);
end;

procedure ReadStringTillZeroW(Text: PChar; Size: LongWord; var Result: String; var Pos: LongWord);
begin
  while (Pos < Size) and ((Text+Pos)^ <> #0) do
  begin
    Result := Result + (Text+Pos)^;
    Inc(Pos,SizeOf(Char));
  end;
  Inc(Pos,SizeOf(Char));
end;

function GetEventCoreText(EventInfo: TDBEventInfo; var Hi: THistoryItem): Boolean;
var
  msg: PWideChar;
begin
  Result := False;
  msg := nil;
  try
    msg := DbEvent_GetTextW(@EventInfo, CP_ACP);
    Result := Assigned(msg);
  except
    if Assigned(msg) then mir_free(msg);
  end;
  if Result then
  begin
    SetString(hi.Text,PChar(msg),StrLen(PChar(msg)));
    mir_free(msg);
  end;
end;

procedure GetEventTextForMessage(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  msgA: PAnsiChar;
  msgW: PChar;
  msglen,lenW: Cardinal;
  i: integer;
begin
  msgA := PAnsiChar(EventInfo.pBlob);
  msgW := nil;
  msglen := lstrlenA(PAnsiChar(EventInfo.pBlob)) + 1;
  if msglen > Cardinal(EventInfo.cbBlob) then
    msglen := EventInfo.cbBlob;
  if Boolean(EventInfo.flags and DBEF_UTF) then
  begin
    SetLength(Hi.Text, msglen);
    lenW := Utf8ToWideChar(PChar(Hi.Text), msglen, msgA, msglen - 1, Hi.CodePage);
    if Integer(lenW) > 0 then
      SetLength(Hi.Text, lenW - 1)
    else
      Hi.Text := AnsiToWideString(msgA, Hi.CodePage, msglen - 1);
  end
  else
  begin
    lenW := 0;
    if Cardinal(EventInfo.cbBlob) >= msglen * SizeOf(Char) then
    begin
      msgW := PChar(msgA + msglen);
      for i := 0 to ((Cardinal(EventInfo.cbBlob) - msglen) div SizeOf(Char)) - 1 do
        if msgW[i] = #0 then
        begin
          lenW := i;
          break;
        end;
    end;
    if (lenW > 0) and (lenW < msglen) then
      SetString(Hi.Text, msgW, lenW)
    else
      Hi.Text := AnsiToWideString(msgA, Hi.CodePage, msglen - 1);
  end;
end;

procedure GetEventTextForUrl(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  BytePos:LongWord;
  Url,Desc: AnsiString;
  cp: Cardinal;
begin
  BytePos:=0;
  ReadStringTillZeroA(Pointer(EventInfo.pBlob),EventInfo.cbBlob,Url,BytePos);
  ReadStringTillZeroA(Pointer(EventInfo.pBlob),EventInfo.cbBlob,Desc,BytePos);
  if Boolean(EventInfo.flags and DBEF_UTF) then
    cp := CP_UTF8
  else
    cp := Hi.CodePage;
  hi.Text := Format(TranslateW('URL: %s'),[AnsiToWideString(url+#13#10+desc,cp)]);
  hi.Extended := Url;
end;

procedure GetEventTextForFile(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  PText: PWideChar;
  cp: Cardinal;
begin
  if Boolean(EventInfo.flags and DBEF_SENT) then
    Hi.Text := 'Outgoing file transfer: %s'
  else
    Hi.Text := 'Incoming file transfer: %s';
  if Boolean(EventInfo.flags and DBEF_UTF) then
    cp := CP_UTF8
  else
    cp := Hi.CodePage;
  PText := DbEvent_GetTextW(@EventInfo, CP_ACP);
  if not Assigned(PText) then
     PText := mir_wstrdup('');
  Hi.Text := Format(TranslateUnicodeString(Hi.Text), [PText]);
  Hi.Extended := '';
end;

procedure GetEventTextForAuthRequest(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  BytePos: LongWord;
  uin:integer;
  hContact: THandle;
  Nick,Name,Email,Reason: AnsiString;
  NickW,ReasonW,ReasonUTF,ReasonACP: String;
begin
  // blob is: uin(DWORD), hContact(THANDLE), nick(ASCIIZ), first(ASCIIZ), last(ASCIIZ), email(ASCIIZ)
  uin := PDWord(EventInfo.pBlob)^;
  hContact := PDWord(uint_ptr(Pointer(EventInfo.pBlob)) + SizeOf(dword))^;
  BytePos := SizeOf(dword)*2;
  // read nick
  ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Nick, BytePos);
  if Nick = '' then
    NickW := GetContactDisplayName(hContact, '', true)
  else
    NickW := AnsiToWideString(Nick, CP_ACP);
  // read first name
  ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Name, BytePos);
  Name := Name + ' ';
  // read last name
  ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Name, BytePos);
  Name := AnsiString(Trim(String(Name)));
  if Name <> '' then
    Name := Name + ', ';
  // read Email
  ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Email, BytePos);
  if Email <> '' then
    Email := Email + ', ';
  // read reason
  ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Reason, BytePos);

  ReasonUTF := AnsiToWideString(Reason, CP_UTF8);
  ReasonACP := AnsiToWideString(Reason, hppCodepage);
  if (Length(ReasonUTF) > 0) and (Length(ReasonUTF) < Length(ReasonACP)) then
    ReasonW := ReasonUTF
  else
    ReasonW := ReasonACP;
  Hi.Text := Format(TranslateW('Authorization request by %s (%s%d): %s'),
    [NickW, AnsiToWideString(Name + Email, hppCodepage), uin, ReasonW]);
end;

procedure GetEventTextForYouWereAdded(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  BytePos: LongWord;
  uin: integer;
  hContact:THandle;
  Nick,Name,Email: AnsiString;
  NickW: String;
begin
  // blob is: uin(DWORD), hContact(THANDLE), nick(ASCIIZ), first(ASCIIZ), last(ASCIIZ), email(ASCIIZ)
  uin := PDWord(EventInfo.pBlob)^;
  hContact := PDWord(uint_ptr(Pointer(EventInfo.pBlob)) + SizeOf(dword))^;
  BytePos := SizeOf(dword)*2;
  // read nick
  ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Nick, BytePos);
  if Nick = '' then
    NickW := GetContactDisplayName(hContact, '', true)
  else
    NickW := AnsiToWideString(Nick, CP_ACP);
  // read first name
  ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Name, BytePos);
  Name := Name + ' ';
  // read last name
  ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Name, BytePos);
  Name := AnsiString(Trim(String(Name)));
  if Name <> '' then
    Name := Name + ', ';
  ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Email, BytePos);
  if Email <> '' then
    Email := Email + ', ';
  Hi.Text := Format(TranslateW('You were added by %s (%s%d)'),
    [NickW, AnsiToWideString(Name + Email, hppCodepage), uin]);
end;

procedure GetEventTextForSms(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  cp: Cardinal;
begin
  if Boolean(EventInfo.flags and DBEF_UTF) then
    cp := CP_UTF8
  else
    cp := Hi.CodePage;
  Hi.Text := AnsiToWideString(PAnsiChar(EventInfo.pBlob), cp);
end;

procedure GetEventTextForContacts(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  BytePos: LongWord;
  Contacts: AnsiString;
  cp: Cardinal;
begin
  BytePos := 0;
  Contacts := '';
  While BytePos < Cardinal(EventInfo.cbBlob) do
  begin
    Contacts := Contacts + #13#10;
    ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Contacts, BytePos);
    Contacts := Contacts + ' (ICQ: ';
    ReadStringTillZeroA(Pointer(EventInfo.pBlob), EventInfo.cbBlob, Contacts, BytePos);
    Contacts := Contacts + ')';
  end;
  if Boolean(EventInfo.flags and DBEF_SENT) then
    Hi.Text := 'Outgoing contacts: %s'
  else
    Hi.Text := 'Incoming contacts: %s';
  if Boolean(EventInfo.flags and DBEF_UTF) then
    cp := CP_UTF8
  else
    cp := Hi.CodePage;
  hi.Text := Format(TranslateUnicodeString(hi.Text),[AnsiToWideString(Contacts,cp)]);
end;

procedure GetEventTextForStatusChange(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  tmp: THistoryItem;
begin
  tmp.Codepage := hppCodepage;
  GetEventTextForMessage(EventInfo,tmp);
  hi.Text := Format(TranslateW('Status change: %s'),[tmp.Text]);
end;

procedure GetEventTextForAvatarChange(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  msgA: PAnsiChar;
  msgW: PWideChar;
  msglen,lenW: Cardinal;
  i: integer;
begin
  msgA := PAnsiChar(EventInfo.pBlob);
  msgW := nil;
  msglen := lstrlenA(PAnsiChar(EventInfo.pBlob)) + 1;
  if msglen > Cardinal(EventInfo.cbBlob) then
    msglen := EventInfo.cbBlob;
  if Boolean(EventInfo.flags and DBEF_UTF) then
  begin
    SetLength(Hi.Text, msglen);
    lenW := Utf8ToWideChar(PWideChar(Hi.Text), msglen, msgA, msglen - 1, Hi.CodePage);
    if Integer(lenW) > 0 then
      SetLength(Hi.Text, lenW - 1)
    else
      Hi.Text := AnsiToWideString(msgA, Hi.CodePage, msglen - 1);
  end
  else
  begin
    lenW := 0;
    if Cardinal(EventInfo.cbBlob) >= msglen * SizeOf(WideChar) then
    begin
      msgW := PWideChar(msgA + msglen);
      for i := 0 to ((Cardinal(EventInfo.cbBlob) - msglen) div SizeOf(WideChar)) - 1 do
        if msgW[i] = #0 then
        begin
          lenW := i;
          break;
        end;
    end;
    if (lenW > 0) and (lenW < msglen) then
      SetString(Hi.Text, msgW, lenW)
    else
      Hi.Text := AnsiToWideString(msgA, Hi.CodePage, msglen - 1);
    msglen := msglen + (lenW + 1) * SizeOf(WideChar);
  end;
  if msglen < Cardinal(EventInfo.cbBlob) then
  begin
    msgA := msgA + msglen;
    if lstrlenA(msgA) > 0 then
      Hi.Extended := msgA;
  end;
end;

procedure GetEventTextForJabberChatStates(EventInfo: TDBEventInfo; var Hi: THistoryItem);
begin
  if EventInfo.cbBlob = 0 then exit;
  case PByte(EventInfo.pBlob)^ of
    JABBER_DB_EVENT_CHATSTATES_GONE:
      hi.Text := TranslateW('closed chat session');
  end;
end;

procedure GetEventTextWATrackRequest(EventInfo: TDBEventInfo; var Hi: THistoryItem);
begin
  hi.Text := TranslateW('WATrack: information request');
end;

procedure GetEventTextWATrackAnswer(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  BytePos: LongWord;
  Artist,Title,Album,Template: String;
begin
  BytePos := 0;
  ReadStringTillZeroW(Pointer(EventInfo.pBlob),EventInfo.cbBlob,Artist,BytePos);
  ReadStringTillZeroW(Pointer(EventInfo.pBlob),EventInfo.cbBlob,Title,BytePos);
  ReadStringTillZeroW(Pointer(EventInfo.pBlob),EventInfo.cbBlob,Album,BytePos);
  ReadStringTillZeroW(Pointer(EventInfo.pBlob),EventInfo.cbBlob,Template,BytePos);
  if (Artist <> '') or (Title <> '') or (Album <> '') then
  begin
    if Template <> '' then
      Template := Template + #13#10;
    Template := Template + WideFormat
      (FormatCString(TranslateW('Artist: %s\r\nTitle: %s\r\nAlbum: %s')),
      [Artist, Title, Album]);
  end;
  hi.Text := Format(TranslateW('WATrack: %s'),[Template]);
end;

procedure GetEventTextWATrackError(EventInfo: TDBEventInfo; var Hi: THistoryItem);
begin
  hi.Text := TranslateW('WATrack: request denied');
end;

procedure GetEventTextForOther(EventInfo: TDBEventInfo; var Hi: THistoryItem);
var
  cp: Cardinal;
begin
  TextBuffer.Allocate(EventInfo.cbBlob+1);
  StrLCopy(TextBuffer.Buffer,PAnsiChar(EventInfo.pBlob),EventInfo.cbBlob);
  if Boolean(EventInfo.flags and DBEF_UTF) then
    cp := CP_UTF8
  else
    cp := Hi.CodePage;
  hi.Text := AnsiToWideString(PAnsiChar(TextBuffer.Buffer),cp);
end;

initialization
  EventBuffer := THppBuffer.Create;
  TextBuffer  := THppBuffer.Create;

finalization
  EventBuffer.Destroy;
  TextBuffer.Destroy;
  SetLength(ModuleEventRecords,0);

end.