// ==++==
//
//   Copyright (c) Microsoft Corporation.  All rights reserved.
//
// ==--==
namespace System.Globalization
{

    using System;
    using System.Runtime.InteropServices;    
    using System.Runtime.CompilerServices;
    using System.Runtime.Versioning;
    using System.Diagnostics.Contracts;

// 


    //
    // List of calendar data
    // Note the we cache overrides.
    // Note that localized names (resource names) aren't available from here.
    //
    //  NOTE: Calendars depend on the locale name that creates it.  Only a few
    //            properties are available without locales using CalendarData.GetCalendar(int)

    // StructLayout is needed here otherwise compiler can re-arrange the fields.
    // We have to keep this in-sync with the definition in calendardata.h
    //
    // WARNING WARNING WARNING
    //
    // WARNING: Anything changed here also needs to be updated on the native side (object.h see type CalendarDataBaseObject)
    // WARNING: The type loader will rearrange class member offsets so the mscorwks!CalendarDataBaseObject
    // WARNING: must be manually structured to match the true loaded class layout
    //
    internal partial class CalendarData
    {
        // Max calendars
        internal const int MAX_CALENDARS = 23;

        // Identity
        internal String     sNativeName              ; // Calendar Name for the locale

        // Formats
        internal String[]   saShortDates             ; // Short Data format, default first
        internal String[]   saYearMonths             ; // Year/Month Data format, default first
        internal String[]   saLongDates              ; // Long Data format, default first
        internal String     sMonthDay                ; // Month/Day format

        // Calendar Parts Names
        internal String[]   saEraNames               ; // Names of Eras
        internal String[]   saAbbrevEraNames         ; // Abbreviated Era Names
        internal String[]   saAbbrevEnglishEraNames  ; // Abbreviated Era Names in English
        internal String[]   saDayNames               ; // Day Names, null to use locale data, starts on Sunday
        internal String[]   saAbbrevDayNames         ; // Abbrev Day Names, null to use locale data, starts on Sunday
        internal String[]   saSuperShortDayNames     ; // Super short Day of week names
        internal String[]   saMonthNames             ; // Month Names (13)
        internal String[]   saAbbrevMonthNames       ; // Abbrev Month Names (13)
        internal String[]   saMonthGenitiveNames     ; // Genitive Month Names (13)
        internal String[]   saAbbrevMonthGenitiveNames; // Genitive Abbrev Month Names (13)
        internal String[]   saLeapYearMonthNames     ; // Multiple strings for the month names in a leap year.

        // Integers at end to make marshaller happier
        internal int        iTwoDigitYearMax=2029    ; // Max 2 digit year (for Y2K bug data entry)
        internal int        iCurrentEra=0            ;  // current era # (usually 1)

        // Use overrides?
        internal bool       bUseUserOverrides        ; // True if we want user overrides.

        // Static invariant for the invariant locale
        internal static CalendarData Invariant;

        // Private constructor
        private CalendarData() {}

        // Invariant constructor
        static CalendarData()
        {

            // Set our default/gregorian US calendar data
            // Calendar IDs are 1-based, arrays are 0 based.
            CalendarData invariant = new CalendarData();

            // Set default data for calendar
            // Note that we don't load resources since this IS NOT supposed to change (by definition)
            invariant.sNativeName           = "Gregorian Calendar";  // Calendar Name

            // Year
            invariant.iTwoDigitYearMax      = 2029; // Max 2 digit year (for Y2K bug data entry)
            invariant.iCurrentEra           = 1; // Current era #

            // Formats
            invariant.saShortDates          = new String[] { "MM/dd/yyyy", "yyyy-MM-dd" };          // short date format
            invariant.saLongDates           = new String[] { "dddd, dd MMMM yyyy"};                 // long date format
            invariant.saYearMonths          = new String[] { "yyyy MMMM" };                         // year month format
            invariant.sMonthDay             = "MMMM dd";                                            // Month day pattern

            // Calendar Parts Names
            invariant.saEraNames            = new String[] { "A.D." };     // Era names
            invariant.saAbbrevEraNames      = new String[] { "AD" };      // Abbreviated Era names
            invariant.saAbbrevEnglishEraNames=new String[] { "AD" };     // Abbreviated era names in English
            invariant.saDayNames            = new String[] { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday" };// day names
            invariant.saAbbrevDayNames      = new String[] { "Sun",    "Mon",    "Tue",     "Wed",       "Thu",      "Fri",    "Sat" };     // abbreviated day names
            invariant.saSuperShortDayNames  = new String[] { "Su",     "Mo",     "Tu",      "We",        "Th",       "Fr",     "Sa" };      // The super short day names
            invariant.saMonthNames          = new String[] { "January", "February", "March", "April", "May", "June", 
                                                            "July", "August", "September", "October", "November", "December", String.Empty}; // month names
            invariant.saAbbrevMonthNames    = new String[] { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
                                                            "Jul", "Aug", "Sep", "Oct", "Nov", "Dec", String.Empty}; // abbreviated month names
            invariant.saMonthGenitiveNames  = invariant.saMonthNames;              // Genitive month names (same as month names for invariant)
            invariant.saAbbrevMonthGenitiveNames=invariant.saAbbrevMonthNames;    // Abbreviated genitive month names (same as abbrev month names for invariant)
            invariant.saLeapYearMonthNames  = invariant.saMonthNames;              // leap year month names are unused in Gregorian English (invariant)

            invariant.bUseUserOverrides     = false;

            // Calendar was built, go ahead and assign it...            
            Invariant = invariant;
        }



        //
        // Get a bunch of data for a calendar
        //
        internal CalendarData(String localeName, int calendarId, bool bUseUserOverrides)
        {
            // Call nativeGetCalendarData to populate the data
            this.bUseUserOverrides = bUseUserOverrides;
            if (!nativeGetCalendarData(this, localeName, calendarId))
            {
                Contract.Assert(false, "[CalendarData] nativeGetCalendarData call isn't expected to fail for calendar " + calendarId + " locale " +localeName);
                
                // Something failed, try invariant for missing parts
                // This is really not good, but we don't want the callers to crash.
                if (this.sNativeName == null)   this.sNativeName  = String.Empty;           // Calendar Name for the locale.
                
                // Formats
                if (this.saShortDates == null)  this.saShortDates = Invariant.saShortDates; // Short Data format, default first
                if (this.saYearMonths == null)  this.saYearMonths = Invariant.saYearMonths; // Year/Month Data format, default first
                if (this.saLongDates == null)   this.saLongDates  = Invariant.saLongDates;  // Long Data format, default first
                if (this.sMonthDay == null)     this.sMonthDay    = Invariant.sMonthDay;    // Month/Day format
                
                // Calendar Parts Names
                if (this.saEraNames == null)              this.saEraNames              = Invariant.saEraNames;              // Names of Eras
                if (this.saAbbrevEraNames == null)        this.saAbbrevEraNames        = Invariant.saAbbrevEraNames;        // Abbreviated Era Names
                if (this.saAbbrevEnglishEraNames == null) this.saAbbrevEnglishEraNames = Invariant.saAbbrevEnglishEraNames; // Abbreviated Era Names in English
                if (this.saDayNames == null)              this.saDayNames              = Invariant.saDayNames;              // Day Names, null to use locale data, starts on Sunday
                if (this.saAbbrevDayNames == null)        this.saAbbrevDayNames        = Invariant.saAbbrevDayNames;        // Abbrev Day Names, null to use locale data, starts on Sunday
                if (this.saSuperShortDayNames == null)    this.saSuperShortDayNames    = Invariant.saSuperShortDayNames;    // Super short Day of week names
                if (this.saMonthNames == null)            this.saMonthNames            = Invariant.saMonthNames;            // Month Names (13)
                if (this.saAbbrevMonthNames == null)      this.saAbbrevMonthNames      = Invariant.saAbbrevMonthNames;      // Abbrev Month Names (13)
                // Genitive and Leap names can follow the fallback below
            }

            // Clean up the escaping of the formats
            this.saShortDates = CultureData.ReescapeWin32Strings(this.saShortDates);
            this.saLongDates = CultureData.ReescapeWin32Strings(this.saLongDates);
            this.saYearMonths = CultureData.ReescapeWin32Strings(this.saYearMonths);
            this.sMonthDay = CultureData.ReescapeWin32String(this.sMonthDay);

            if ((CalendarId)calendarId == CalendarId.TAIWAN)
            {
                // for Geo----al reasons, the ----ese native name should only be returned when 
                // for ----ese SKU
                if (CultureInfo.IsTaiwanSku)
                {
                    // We got the month/day names from the OS (same as gregorian), but the native name is wrong
                    this.sNativeName = "\x4e2d\x83ef\x6c11\x570b\x66c6";
                }
                else
                {
                    this.sNativeName = String.Empty;
                }
            }

            // Check for null genitive names (in case unmanaged side skips it for non-gregorian calendars, etc)
            if (this.saMonthGenitiveNames == null || String.IsNullOrEmpty(this.saMonthGenitiveNames[0]))
                this.saMonthGenitiveNames = this.saMonthNames;              // Genitive month names (same as month names for invariant)
            if (this.saAbbrevMonthGenitiveNames == null || String.IsNullOrEmpty(this.saAbbrevMonthGenitiveNames[0]))
                this.saAbbrevMonthGenitiveNames = this.saAbbrevMonthNames;    // Abbreviated genitive month names (same as abbrev month names for invariant)
            if (this.saLeapYearMonthNames == null || String.IsNullOrEmpty(this.saLeapYearMonthNames[0]))
                this.saLeapYearMonthNames = this.saMonthNames;

            InitializeEraNames(localeName, calendarId);

            InitializeAbbreviatedEraNames(localeName, calendarId);

            // Abbreviated English Era Names are only used for the Japanese calendar.
            if (!GlobalizationMode.Invariant && calendarId == (int)CalendarId.JAPAN)
            {
                this.saAbbrevEnglishEraNames = GetJapaneseEnglishEraNames();
            }
            else
            {
                // For all others just use the an empty string (doesn't matter we'll never ask for it for other calendars)
                this.saAbbrevEnglishEraNames = new String[] { "" };
            }

            // Japanese is the only thing with > 1 era.  Its current era # is how many ever 
            // eras are in the array.  (And the others all have 1 string in the array)
            this.iCurrentEra = this.saEraNames.Length;
        }

        private void InitializeEraNames(string localeName, int calendarId)
        {
            // Note that the saEraNames only include "A.D."  We don't have localized names for other calendars available from windows
            switch ((CalendarId)calendarId)
            {
                    // For Localized Gregorian we really expect the data from the OS.
                case CalendarId.GREGORIAN:
                    // Fallback for CoreCLR < Win7 or culture.dll missing            
                    if (this.saEraNames == null || this.saEraNames.Length == 0 || String.IsNullOrEmpty(this.saEraNames[0]))
                    {
                        this.saEraNames = new String[] { "A.D." };
                    }
                    break;

                    // The rest of the calendars have constant data, so we'll just use that
                case CalendarId.GREGORIAN_US:
                case CalendarId.JULIAN:
                    this.saEraNames = new String[] { "A.D." };
                    break;
                case CalendarId.HEBREW:
                    this.saEraNames = new String[] { "C.E." };
                    break;
                case CalendarId.HIJRI:
                case CalendarId.UMALQURA:
                    if (localeName == "dv-MV")
                    {
                        // Special case for Divehi
                        this.saEraNames = new String[] { "\x0780\x07a8\x0796\x07b0\x0783\x07a9" };
                    }
                    else
                    {
                        this.saEraNames = new String[] { "\x0628\x0639\x062F \x0627\x0644\x0647\x062C\x0631\x0629" };
                    }
                    break;
                case CalendarId.GREGORIAN_ARABIC:
                case CalendarId.GREGORIAN_XLIT_ENGLISH:
                case CalendarId.GREGORIAN_XLIT_FRENCH:
                    // These are all the same:
                    this.saEraNames = new String[] { "\x0645" };
                    break;

                case CalendarId.GREGORIAN_ME_FRENCH:
                    this.saEraNames = new String[] { "ap. J.-C." };
                    break;
                    
                case CalendarId.TAIWAN:
                    // for Geo----al reasons, the ----ese native name should only be returned when 
                    // for ----ese SKU
                    if (CultureInfo.IsTaiwanSku)
                    {
                        // 
                        this.saEraNames = new String[] { "\x4e2d\x83ef\x6c11\x570b" };
                    }
                    else
                    {
                        this.saEraNames = new String[] { String.Empty };
                    }
                    break;

                case CalendarId.KOREA:
                    this.saEraNames = new String[] { "\xb2e8\xae30" };
                    break;
                    
                case CalendarId.THAI:
                    this.saEraNames = new String[] { "\x0e1e\x002e\x0e28\x002e" };
                    break;
                    
                case CalendarId.JAPAN:
                case CalendarId.JAPANESELUNISOLAR:
                    this.saEraNames = GetJapaneseEraNames ();
                    break;

                case CalendarId.PERSIAN:
                    if (this.saEraNames == null || this.saEraNames.Length == 0 || String.IsNullOrEmpty(this.saEraNames[0]))
                    {
                        this.saEraNames = new String[] { "\x0647\x002e\x0634" };
                    }
                    break;

                default:
                    // Most calendars are just "A.D."
                    this.saEraNames = Invariant.saEraNames;
                    break;
            }
        }

        private static string[] GetJapaneseEraNames()
        {
            if (GlobalizationMode.Invariant)
                throw new PlatformNotSupportedException();
            return JapaneseCalendar.EraNames();
        }

        private static string[] GetJapaneseEnglishEraNames()
        {
            if (GlobalizationMode.Invariant)
                throw new PlatformNotSupportedException();
            return JapaneseCalendar.EnglishEraNames();
        }

        private void InitializeAbbreviatedEraNames(string localeName, int calendarId)
        {
            // Note that the saAbbrevEraNames only include "AD"  We don't have localized names for other calendars available from windows
            switch ((CalendarId)calendarId)
            {
                    // For Localized Gregorian we really expect the data from the OS.
                case CalendarId.GREGORIAN:
                    // Fallback for CoreCLR < Win7 or culture.dll missing            
                    if (this.saAbbrevEraNames == null || this.saAbbrevEraNames.Length == 0 || String.IsNullOrEmpty(this.saAbbrevEraNames[0]))
                    {
                        this.saAbbrevEraNames = new String[] { "AD" };
                    }
                    break;

                    // The rest of the calendars have constant data, so we'll just use that
                case CalendarId.GREGORIAN_US:
                case CalendarId.JULIAN:                        
                    this.saAbbrevEraNames = new String[] { "AD" };
                    break;                    
                case CalendarId.JAPAN:
                case CalendarId.JAPANESELUNISOLAR:
                    if (GlobalizationMode.Invariant)
                    {
                        throw new PlatformNotSupportedException();
                    }
                    this.saAbbrevEraNames = this.saEraNames;
                    break;
                case CalendarId.HIJRI:
                case CalendarId.UMALQURA:
                    if (localeName == "dv-MV")
                    {
                        // Special case for Divehi
                        this.saAbbrevEraNames = new String[] { "\x0780\x002e" };
                    }
                    else
                    {
                        this.saAbbrevEraNames = new String[] { "\x0647\x0640" };
                    }
                    break;
                case CalendarId.TAIWAN:
                    // Get era name and abbreviate it
                    this.saAbbrevEraNames = new String[1];
                    if (this.saEraNames[0].Length == 4)
                    {
                        this.saAbbrevEraNames[0] = this.saEraNames[0].Substring(2,2);
                    }
                    else
                    {
                        this.saAbbrevEraNames[0] = this.saEraNames[0];
                    }                        
                    break;

                case CalendarId.PERSIAN:
                    if (this.saAbbrevEraNames == null || this.saAbbrevEraNames.Length == 0 || String.IsNullOrEmpty(this.saAbbrevEraNames[0]))
                    {
                        this.saAbbrevEraNames = this.saEraNames;
                    }
                    break;

                default:
                    // Most calendars just use the full name
                    this.saAbbrevEraNames = this.saEraNames;
                    break;
            }
        }

        internal static CalendarData GetCalendarData(int calendarId)
        {
            //
            // Get a calendar.
            // Unfortunately we depend on the locale in the OS, so we need a locale
            // no matter what.  So just get the appropriate calendar from the 
            // appropriate locale here
            //

            // Get a culture name
            // 
            String culture = CalendarIdToCultureName(calendarId);
           
            // Return our calendar
            return CultureInfo.GetCultureInfo(culture).m_cultureData.GetCalendar(calendarId);
        }

        //
        // Helper methods
        //
        private static String CalendarIdToCultureName(int calendarId)
        {
            switch (calendarId)
            {
                case Calendar.CAL_GREGORIAN_US: 
                    return "fa-IR";             // "fa-IR" Iran
                    
                case Calendar.CAL_JAPAN:
                    return "ja-JP";             // "ja-JP" Japan
                
                case Calendar.CAL_TAIWAN:
                    return "zh-TW";             // zh-TW Taiwan
                
                case Calendar.CAL_KOREA:            
                    return "ko-KR";             // "ko-KR" Korea
                    
                case Calendar.CAL_HIJRI:
                case Calendar.CAL_GREGORIAN_ARABIC:
                case Calendar.CAL_UMALQURA:
                    return "ar-SA";             // "ar-SA" Saudi Arabia

                case Calendar.CAL_THAI:
                    return "th-TH";             // "th-TH" Thailand
                    
                case Calendar.CAL_HEBREW:
                    return "he-IL";             // "he-IL" Israel
                    
                case Calendar.CAL_GREGORIAN_ME_FRENCH:
                    return "ar-DZ";             // "ar-DZ" Algeria
                
                case Calendar.CAL_GREGORIAN_XLIT_ENGLISH:
                case Calendar.CAL_GREGORIAN_XLIT_FRENCH:
                    return "ar-IQ";             // "ar-IQ"; Iraq
                
                default:
                    // Default to gregorian en-US
                    break;
            }

            return "en-US";
        }
#if !MONO_CULTURE_DATA
        internal void FixupWin7MonthDaySemicolonBug()
        {
            int unescapedCharacterIndex = FindUnescapedCharacter(sMonthDay, ';');
            if (unescapedCharacterIndex > 0)
            {
                sMonthDay = sMonthDay.Substring(0, unescapedCharacterIndex);
            }
        }
        private static int FindUnescapedCharacter(string s, char charToFind)
        {
            bool inComment = false;
            int length = s.Length;
            for (int i = 0; i < length; i++)
            {
                char c = s[i];

                switch (c)
                {
                    case '\'':
                        inComment = !inComment;
                        break;
                    case '\\':
                        i++; // escape sequence -- skip next character
                        break;
                    default:
                        if (!inComment && charToFind == c)
                        {
                            return i;
                        }
                        break;
                }
            }
            return -1;
        }

        
        // Get native two digit year max
        [System.Security.SecurityCritical]  // auto-generated
        [ResourceExposure(ResourceScope.None)]
        [MethodImplAttribute(MethodImplOptions.InternalCall)]
        internal static extern int nativeGetTwoDigitYearMax(int calID);

        // Call native side to load our calendar data
        [System.Security.SecuritySafeCritical]  // auto-generated
        [ResourceExposure(ResourceScope.None)]
        [MethodImplAttribute(MethodImplOptions.InternalCall)]
        private static extern bool nativeGetCalendarData(CalendarData data, String localeName, int calendar);

        // Call native side to figure out which calendars are allowed
        [System.Security.SecuritySafeCritical]  // auto-generated
        [ResourceExposure(ResourceScope.None)]
        [MethodImplAttribute(MethodImplOptions.InternalCall)]
        internal static extern int nativeGetCalendars(String localeName, bool useUserOverride, [In, Out] int[] calendars);
#endif
    }
 }