/////////////////////////////////////////////////////////////////////////////
//
// Backport from wxWidgets-3.0-rc1
//
/////////////////////////////////////////////////////////////////////////////
// Name:        src/common/numformatter.cpp
// Purpose:     NumberFormatter
// Author:      Fulvio Senore, Vadim Zeitlin
// Created:     2010-11-06
// Copyright:   (c) 2010 wxWidgets team
// Licence:     wxWindows licence
/////////////////////////////////////////////////////////////////////////////

// ----------------------------------------------------------------------------
// headers
// ----------------------------------------------------------------------------

// For compilers that support precompilation, includes "wx.h".
#include <wx/wxprec.h>

#ifdef __BORLANDC__
    #pragma hdrstop
#endif

#ifdef __WIN32__
    #include <wx/msw/private.h>

#endif


#include "numformatter.h"
#include <wx/intl.h>

#include <locale.h> // for setlocale and LC_ALL
#include <wx/log.h>

// ----------------------------------------------------------------------------
// local helpers
// ----------------------------------------------------------------------------

namespace
{

// Contains information about the locale which was used to initialize our
// cached values of the decimal and thousands separators. Notice that it isn't
// enough to store just wxLocale because the user code may call setlocale()
// directly and storing just C locale string is not enough because we can use
// the OS API directly instead of the CRT ones on some platforms. So just store
// both.
class LocaleId
{
public:
    LocaleId()
    {
#if wxUSE_INTL
        m_wxloc = NULL;
#endif // wxUSE_INTL
        m_cloc = NULL;
    }

    ~LocaleId()
    {
        Free();
    }

#if wxUSE_INTL
    // Return true if this is the first time this function is called for this
    // object or if the program locale has changed since the last time it was
    // called. Otherwise just return false indicating that updating locale-
    // dependent information is not necessary.
    bool NotInitializedOrHasChanged()
    {
        wxLocale * const wxloc = wxGetLocale();
        const char * const cloc = setlocale(LC_ALL, NULL);
        if ( m_wxloc || m_cloc )
        {
            if ( m_wxloc == wxloc && strcmp(m_cloc, cloc) == 0 )
                return false;

            Free();
        }
        //else: Not initialized yet.

        m_wxloc = wxloc;
        m_cloc = strdup(cloc);

        return true;
    }
#endif // wxUSE_INTL

private:
    void Free()
    {
#if wxUSE_INTL
        free(m_cloc);
#endif // wxUSE_INTL
    }

#if wxUSE_INTL
    // Non-owned pointer to wxLocale which was used.
    wxLocale *m_wxloc;
#endif // wxUSE_INTL

    // Owned pointer to the C locale string.
    char *m_cloc;

//    wxDECLARE_NO_COPY_CLASS(LocaleId);
};

} // anonymous namespace

// ============================================================================
// NumberFormatter implementation
// ============================================================================

// ----------------------------------------------------------------------------
// Locale information accessors
// ----------------------------------------------------------------------------

wxChar NumberFormatter::GetDecimalSeparator()
{
#if wxUSE_INTL
    // Notice that while using static variable here is not MT-safe, the worst
    // that can happen is that we redo the initialization if we're called
    // concurrently from more than one thread so it's not a real problem.
    static wxChar s_decimalSeparator = 0;

    // Remember the locale which was current when we initialized, we must redo
    // the initialization if the locale changed.
    static LocaleId s_localeUsedForInit;

    if ( s_localeUsedForInit.NotInitializedOrHasChanged() )
    {
        const wxString
            s = wxLocale::GetInfo(wxLOCALE_DECIMAL_POINT, wxLOCALE_CAT_NUMBER);
        if ( s.empty() )
        {
            // We really must have something for decimal separator, so fall
            // back to the C locale default.
            s_decimalSeparator = '.';
        }
        else
        {
            // To the best of my knowledge there are no locales like this.
            wxASSERT_MSG( s.length() == 1,
                          wxT("Multi-character decimal separator?") );

            s_decimalSeparator = s[0];
        }
    }

    return s_decimalSeparator;
#else // !wxUSE_INTL
    return wxT('.');
#endif // wxUSE_INTL/!wxUSE_INTL
}

bool NumberFormatter::GetThousandsSeparatorIfUsed(wxChar *sep)
{
#if wxUSE_INTL
    static wxChar s_thousandsSeparator = 0;
    static LocaleId s_localeUsedForInit;

    if ( s_localeUsedForInit.NotInitializedOrHasChanged() )
    {
#if defined(__WXMSW__)
       wxUint32 lcid = LOCALE_USER_DEFAULT;

       if (wxGetLocale())
       {
          const wxLanguageInfo *info = wxLocale::GetLanguageInfo(wxGetLocale()->GetLanguage());
           if (info)
           {                         ;
               lcid = MAKELCID(MAKELANGID(info->WinLang, info->WinSublang),
                                        SORT_DEFAULT);
           }
       }

       wxString s;
       wxChar buffer[256];
       buffer[0] = wxT('\0');
       size_t count = GetLocaleInfo(lcid, LOCALE_STHOUSAND, buffer, 256);
       if (!count)
           s << wxT(",");
       else
           s << buffer;
#else
        wxString
          s = wxLocale::GetInfo(wxLOCALE_THOUSANDS_SEP, wxLOCALE_CAT_NUMBER);
#endif
        if ( !s.empty() )
        {
            wxASSERT_MSG( s.length() == 1,
                          wxT("Multi-character thousands separator?") );

            s_thousandsSeparator = s[0];
        }
        //else: Unlike above it's perfectly fine for the thousands separator to
        //      be empty if grouping is not used, so just leave it as 0.
    }

    if ( !s_thousandsSeparator )
        return false;

    if ( sep )
        *sep = s_thousandsSeparator;

    return true;
#else // !wxUSE_INTL
    wxUnusedVar(sep);
    return false;
#endif // wxUSE_INTL/!wxUSE_INTL
}

// ----------------------------------------------------------------------------
// Conversion to string and helpers
// ----------------------------------------------------------------------------

wxString NumberFormatter::PostProcessIntString(wxString s, int style)
{
    if ( style & Style_WithThousandsSep )
        AddThousandsSeparators(s);

    wxASSERT_MSG( !(style & Style_NoTrailingZeroes),
                  wxT("Style_NoTrailingZeroes can't be used with integer values") );
    wxASSERT_MSG( !(style & Style_OneTrailingZero),
                  wxT("Style_OneTrailingZero can't be used with integer values") );
    wxASSERT_MSG( !(style & Style_TwoTrailingZeroes),
                  wxT("Style_TwoTrailingZeroes can't be used with integer values") );
    wxASSERT_MSG( !(style & Style_ThreeTrailingZeroes),
                  wxT("Style_ThreeTrailingZeroes can't be used with integer values") );

    return s;
}

wxString NumberFormatter::ToString(long val, int style)
{
    return PostProcessIntString(wxString::Format(wxT("%ld"), val), style);
}

#ifdef HAS_LONG_LONG_T_DIFFERENT_FROM_LONG

wxString NumberFormatter::ToString(wxLongLong_t val, int style)
{
#if wxCHECK_VERSION(3,0,0)
   return PostProcessIntString(wxString::Format("%" wxLongLongFmtSpec "d", val),
                                style);
#else
   return PostProcessIntString(wxString::Format(wxT("%") wxLongLongFmtSpec wxT("d"), val),
      style);
#endif
}

#endif // HAS_LONG_LONG_T_DIFFERENT_FROM_LONG

wxString NumberFormatter::ToString(double val, int precision, int style)
{
    wxString format;
    if ( precision == -1 )
    {
        format = wxT("%g");
    }
    else // Use fixed precision.
    {
        format.Printf(wxT("%%.%df"), precision);
    }

    wxString s = wxString::Format(format, val);

    if ( style & Style_WithThousandsSep )
        AddThousandsSeparators(s);

    if ( precision != -1 )
    {
        if ( style & Style_NoTrailingZeroes )
            RemoveTrailingZeroes(s, 0);

        if ( style & Style_OneTrailingZero )
            RemoveTrailingZeroes(s, 1);

        if ( style & Style_TwoTrailingZeroes )
            RemoveTrailingZeroes(s, 2);

        if ( style & Style_ThreeTrailingZeroes )
            RemoveTrailingZeroes(s, 3);
    }
    return s;
}

void NumberFormatter::AddThousandsSeparators(wxString& s)
{
    wxChar thousandsSep;
    if ( !GetThousandsSeparatorIfUsed(&thousandsSep) )
        return;

    size_t pos = s.find(GetDecimalSeparator());
    if ( pos == wxString::npos )
    {
        // Start grouping at the end of an integer number.
        pos = s.length();
    }

    // End grouping at the beginning of the digits -- there could be at a sign
    // before their start.
    const size_t start = s.find_first_of(wxT("0123456789"));

    // We currently group digits by 3 independently of the locale. This is not
    // the right thing to do and we should use lconv::grouping (under POSIX)
    // and GetLocaleInfo(LOCALE_SGROUPING) (under MSW) to get information about
    // the correct grouping to use. This is something that needs to be done at
    // wxLocale level first and then used here in the future (TODO).
    const size_t GROUP_LEN = 3;

    while ( pos > start + GROUP_LEN )
    {
        pos -= GROUP_LEN;
        s.insert(pos, thousandsSep);
    }
}

void NumberFormatter::RemoveTrailingZeroes(wxString& s, size_t retain /* = 0 */)
{
   const size_t posDecSep = s.find(GetDecimalSeparator());
   wxCHECK_RET( posDecSep != wxString::npos,
               wxString::Format(wxT("No decimal separator in \"%s\""), s.c_str()) );
   wxCHECK_RET( posDecSep, wxT("Can't start with decimal separator" ));

   // Find the last character to keep.
   size_t posLastCharacterToKeep = s.find_last_not_of(wxT("0"));

   // If it's the decimal separator itself, remove it.
   if ((posLastCharacterToKeep == posDecSep) && (retain == 0)) {
      posLastCharacterToKeep--;
   } else if ((posLastCharacterToKeep - posDecSep) < retain) {
      posLastCharacterToKeep = retain + posDecSep;
   }

   s.erase(posLastCharacterToKeep + 1);
}

// ----------------------------------------------------------------------------
// Conversion from strings
// ----------------------------------------------------------------------------

void NumberFormatter::RemoveThousandsSeparators(wxString& s)
{
    wxChar thousandsSep;
    if ( !GetThousandsSeparatorIfUsed(&thousandsSep) )
        return;

    s.Replace(wxString(thousandsSep), wxString());
}

bool NumberFormatter::FromString(wxString s, long *val)
{
    RemoveThousandsSeparators(s);
    return s.ToLong(val);
}

#ifdef HAS_LONG_LONG_T_DIFFERENT_FROM_LONG

bool NumberFormatter::FromString(wxString s, wxLongLong_t *val)
{
    RemoveThousandsSeparators(s);
    return s.ToLongLong(val);
}

#endif // HAS_LONG_LONG_T_DIFFERENT_FROM_LONG

bool NumberFormatter::FromString(wxString s, double *val)
{
    RemoveThousandsSeparators(s);
    return s.ToDouble(val);
}