///////////////////////////////////////////////////////////////////////////////

// Name:        wx/uilocale.h

// Purpose:     wxUILocale class declaration.

// Author:      Vadim Zeitlin

// Created:     2021-07-31

// Copyright:   (c) 2021 Vadim Zeitlin <vadim@wxwidgets.org>

// Licence:     wxWindows licence

///////////////////////////////////////////////////////////////////////////////

#ifndef _WX_UILOCALE_H_

#define _WX_UILOCALE_H_

#include "wx/defs.h"

#if wxUSE_INTL

#include "wx/datetime.h"

#include "wx/localedefs.h"

#include "wx/string.h"

#include "wx/vector.h"

class wxUILocaleImpl;

// Flags for wxUILocale::CompareStrings().

enum

{

    wxCompare_CaseSensitive   = 0,

    wxCompare_CaseInsensitive = 1

};

// Flags for wxLocaleIdent::RemoveLikelySubtags().

enum

{

    wxSubtags_FavourRegion = 0,

    wxSubtags_FavourScript = 1

};

// ----------------------------------------------------------------------------

// wxLocaleIdent: allows to fully identify a locale under all platforms

// ----------------------------------------------------------------------------

class WXDLLIMPEXP_BASE wxLocaleIdent

{

public:

    // Create the object from BCP 47-like language tag: the string must contain

    // at least the language part (2 or 3 ASCII letters) and may contain script

    // and region separated by dashes.

    static wxLocaleIdent FromTag(const wxString& tag);

    // Default ctor creates an empty, invalid identifier.

    wxLocaleIdent() = default;

    // Set language

    wxLocaleIdent& Language(const wxString& language);

    // Set region

    wxLocaleIdent& Region(const wxString& region);

    // Set script (not supported and ignored under Unix)

    wxLocaleIdent& Script(const wxString& script);

    // Set charset (only supported under Unix)

    wxLocaleIdent& Charset(const wxString& charset);

    // Set modifier (only supported under Unix)

    wxLocaleIdent& Modifier(const wxString& modifier);

    // Set extension (only supported under Windows)

    wxLocaleIdent& Extension(const wxString& extension);

    // Set sort order (only supported under Windows)

    wxLocaleIdent& SortOrder(const wxString& sortorder);

    // Accessors for the individual fields.

    const wxString& GetLanguage() const { return m_language; }

    const wxString& GetRegion() const { return m_region; }

    const wxString& GetScript() const { return m_script; }

    const wxString& GetCharset() const { return m_charset; }

    const wxString& GetModifier() const { return m_modifier; }

    const wxString& GetExtension() const { return m_extension; }

    const wxString& GetSortorder() const { return m_sortorder; }

    // Construct platform dependent name

    wxString GetName() const;

    // Get the language tag: for the objects created with FromTag() returns the

    // string passed to it directly, otherwise reconstructs this string from

    // the components.

    wxString GetTag(wxLocaleTagType tagType = wxLOCALE_TAGTYPE_DEFAULT) const;

    // Empty locale identifier is invalid. at least Language() must be called.

    bool IsEmpty() const

    {

        return m_language.empty();

    }

    // Methods for internal use only

    // Find the best match between desired and supported languages/locales.

    static wxString GetBestMatch(const wxVector<wxString>& desired, const wxVector<wxString>& supported);

    static wxString GetBestMatch(const wxString& desired, const wxVector<wxString>& supported);

private:

    wxString m_tag;

    wxString m_language;

    wxString m_region;

    wxString m_script;

    wxString m_charset;

    wxString m_modifier;

    wxString m_extension;

    wxString m_sortorder;

    // Add likely subtags to a given locale identifier.

    static wxLocaleIdent AddLikelySubtags(const wxLocaleIdent& localeIdent);

    // Remove likely subtags from a given locale identifier, favor region.

    static wxLocaleIdent RemoveLikelySubtags(const wxLocaleIdent& localeIdent, int subtagsFavour = wxSubtags_FavourRegion);

};

// ----------------------------------------------------------------------------

// wxUILocale allows to use the default UI locale and get information about it

// ----------------------------------------------------------------------------

class WXDLLIMPEXP_BASE wxUILocale

{

public:

    // Configure the UI to use the default user locale.

    static bool UseDefault();

    // Use the locale corresponding to the given POSIX locale, e.g. "de_DE.UTF-8".

    //

    // This is a compatibility function used by wxWidgets itself, don't use it

    // in the new code.

    static bool UseLocaleName(const wxString& localeName);

    // Return true if the locale was set by calling either UseDefault() or

    // UseLocaleName().

    static bool IsSet();

    // Get the object corresponding to the currently used locale, which is

    // always valid: if IsSet() is false, "C" locale is returned.

    static const wxUILocale& GetCurrent();

    // A helper just to avoid writing wxUILocale(wxLocaleIdent::FromTag(...)).

    static wxUILocale FromTag(const wxString& tag)

    {

        return wxUILocale(wxLocaleIdent::FromTag(tag));

    }

    // Create the object corresponding to the given locale.

    explicit wxUILocale(const wxLocaleIdent& localeId);

    // Objects of this class can be (cheaply) copied.

    wxUILocale(const wxUILocale& loc);

    wxUILocale& operator=(const wxUILocale& loc);

    // Check if the locale is actually supported by the current system: if it's

    // not supported, the other functions will behave as for the "C" locale.

    bool IsSupported() const;

    // Get the platform-dependent name of the current locale.

    wxString GetName() const;

    // Get the locale id from which the current locale was instantiated.

    wxLocaleIdent GetLocaleId() const;

    // Query the locale for the specified information.

    wxString GetInfo(wxLocaleInfo index,

                     wxLocaleCategory cat = wxLOCALE_CAT_DEFAULT) const;

    // Query the locale for the specified localized name.

    wxString GetLocalizedName(wxLocaleName name, wxLocaleForm form) const;

#if wxUSE_DATETIME

    // Get the full (default) or abbreviated localized month name

    // returns empty string on error

    wxString GetMonthName(wxDateTime::Month month,

                          wxDateTime::NameForm form = {}) const;

    // Get the full (default) or abbreviated localized weekday name

    // returns empty string on error

    wxString GetWeekDayName(wxDateTime::WeekDay weekday,

                            wxDateTime::NameForm form = {}) const;

#endif // wxUSE_DATETIME

    // Query the layout direction of the current locale.

    wxLayoutDirection GetLayoutDirection() const;

    // Compares two strings in the order defined by this locale.

    int CompareStrings(const wxString& lhs, const wxString& rhs,

                       int flags = wxCompare_CaseSensitive) const;

    // Note that this class is not supposed to be used polymorphically, hence

    // its dtor is not virtual.

    ~wxUILocale();

    // Return the locale ID representing the default system locale, which would

    // be set is UseDefault() is called.

    static wxLocaleIdent GetSystemLocaleId();

    // Try to get user's (or OS's) preferred language setting.

    // Return wxLANGUAGE_UNKNOWN if the language-guessing algorithm failed

    // Prefer using GetSystemLocaleId() above.

    static int GetSystemLanguage();

    // Try to get user's (or OS's) default locale setting.

    // Return wxLANGUAGE_UNKNOWN if the locale-guessing algorithm failed

    // Prefer using GetSystemLocaleId() above.

    static int GetSystemLocale();

    // Try to retrieve a list of user's (or OS's) preferred UI languages.

    // Return empty list if language-guessing algorithm failed

    static wxVector<wxString> GetPreferredUILanguages();

    // Retrieve the language info struct for the given language

    //

    // Returns nullptr if no info found, pointer must *not* be deleted by caller

    static const wxLanguageInfo* GetLanguageInfo(int lang);

    // Returns language name in English or empty string if the language

    // is not in database

    static wxString GetLanguageName(int lang);

    // Returns ISO code ("canonical name") of language or empty string if the

    // language is not in database

    static wxString GetLanguageCanonicalName(int lang);

    // Find the language for the given locale string which may be either a

    // canonical ISO 2 letter language code ("xx"), a language code followed by

    // the country code ("xx_XX") or a Windows full language name ("Xxxxx...")

    //

    // Returns nullptr if no info found, pointer must *not* be deleted by caller

    static const wxLanguageInfo* FindLanguageInfo(const wxString& locale);

    // Find the language for the given locale string which may be either a

    // canonical ISO 2 letter language code ("xx"), a language code followed by

    // the country code ("xx_XX") or a Windows full language name ("Xxxxx...")

    //

    // Returns nullptr if no info found, pointer must *not* be deleted by caller

    static const wxLanguageInfo* FindLanguageInfo(const wxLocaleIdent& locId);

    // Add custom language to the list of known languages.

    // Notes: 1) wxLanguageInfo contains platform-specific data

    //        2) must be called before Init to have effect

    static void AddLanguage(const wxLanguageInfo& info);

private:

    // This ctor is private and exists only for implementation reasons.

    // It takes ownership of the provided pointer.

    explicit wxUILocale(wxUILocaleImpl* impl = nullptr) : m_impl(impl) { }

    static wxUILocale ms_current;

    wxUILocaleImpl* m_impl;

};

inline wxString wxGetUIDateFormat()

{

    return wxUILocale::GetCurrent().GetInfo(wxLOCALE_SHORT_DATE_FMT);

}

#else // !wxUSE_INTL

inline wxString wxGetUIDateFormat()

{

    return wxString(wxS("%x"));

}

#endif // wxUSE_INTL/!wxUSE_INTL

#endif // _WX_UILOCALE_H_