/*
*******************************************************************************
* Copyright (C) 2003 - 2008, International Business Machines Corporation and  *
* others. All Rights Reserved.                                                *
*******************************************************************************
*/

#include "unicode/utypes.h"

#if !UCONFIG_NO_FORMATTING

#include "cecal.h"
#include "gregoimp.h"   //Math

U_NAMESPACE_BEGIN

static const int32_t LIMITS[UCAL_FIELD_COUNT][4] = {
    // Minimum  Greatest    Least  Maximum
    //           Minimum  Maximum
    {        0,        0,        1,        1}, // ERA
    {        1,        1,  5000000,  5000000}, // YEAR
    {        0,        0,       12,       12}, // MONTH
    {        1,        1,       52,       53}, // WEEK_OF_YEAR
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // WEEK_OF_MONTH
    {        1,        1,        5,       30}, // DAY_OF_MONTH
    {        1,        1,      365,      366}, // DAY_OF_YEAR
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DAY_OF_WEEK
    {       -1,       -1,        1,        5}, // DAY_OF_WEEK_IN_MONTH
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // AM_PM
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // HOUR_OF_DAY
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MINUTE
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // SECOND
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECOND
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // ZONE_OFFSET
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DST_OFFSET
    { -5000000, -5000000,  5000000,  5000000}, // YEAR_WOY
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // DOW_LOCAL
    { -5000000, -5000000,  5000000,  5000000}, // EXTENDED_YEAR
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // JULIAN_DAY
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // MILLISECONDS_IN_DAY
    {/*N/A*/-1,/*N/A*/-1,/*N/A*/-1,/*N/A*/-1}, // IS_LEAP_MONTH
};

//-------------------------------------------------------------------------
// Constructors...
//-------------------------------------------------------------------------

CECalendar::CECalendar(const Locale& aLocale, UErrorCode& success)
:   Calendar(TimeZone::createDefault(), aLocale, success)
{
    setTimeInMillis(getNow(), success);
}

CECalendar::CECalendar (const CECalendar& other) 
:   Calendar(other)
{
}

CECalendar::~CECalendar()
{
}

CECalendar&
CECalendar::operator=(const CECalendar& right)
{
    Calendar::operator=(right);
    return *this;
}

//-------------------------------------------------------------------------
// Calendar framework
//-------------------------------------------------------------------------

int32_t
CECalendar::handleComputeMonthStart(int32_t eyear,int32_t emonth, UBool useMonth) const
{
    return ceToJD(eyear, emonth, 0, getJDEpochOffset());
}

int32_t
CECalendar::handleGetLimit(UCalendarDateFields field, ELimitType limitType) const
{
    return LIMITS[field][limitType];
}

UBool
CECalendar::inDaylightTime(UErrorCode& status) const
{
    if (U_FAILURE(status) || !getTimeZone().useDaylightTime()) {
        return FALSE;
    }

    // Force an update of the state of the Calendar.
    ((CECalendar*)this)->complete(status); // cast away const

    return (UBool)(U_SUCCESS(status) ? (internalGet(UCAL_DST_OFFSET) != 0) : FALSE);
}

UBool
CECalendar::haveDefaultCentury() const
{
    return TRUE;
}

//-------------------------------------------------------------------------
// Calendar system Conversion methods...
//-------------------------------------------------------------------------
int32_t
CECalendar::ceToJD(int32_t year, int32_t month, int32_t date, int32_t jdEpochOffset)
{
    return (int32_t) (
        (jdEpochOffset+365)             // difference from Julian epoch to 1,1,1
        + 365 * (year - 1)              // number of days from years
        + Math::floorDivide(year, 4)    // extra day of leap year
        + 30 * (month + 1)              // number of days from months
        + date                          // number of days for present month
        - 31                            // slack?
        );
}

void
CECalendar::jdToCE(int32_t julianDay, int32_t jdEpochOffset, int32_t& year, int32_t& month, int32_t& day)
{
    int32_t c4; // number of 4 year cycle (1461 days)
    int32_t r4; // remainder of 4 year cycle, always positive

    c4 = Math::floorDivide(julianDay - jdEpochOffset, 1461, r4);

    year = 4 * c4 + (r4/365 - r4/1460); // 4 * <number of 4year cycle> + <years within the last cycle>

    int32_t doy = (r4 == 1460) ? 365 : (r4 % 365); // days in present year

    month = doy / 30;       // 30 -> Coptic/Ethiopic month length up to 12th month
    day = (doy % 30) + 1;   // 1-based days in a month
}

U_NAMESPACE_END

#endif /* #if !UCONFIG_NO_FORMATTING */
//eof