/*****************************************************************************/

// Copyright 2006-2008 Adobe Systems Incorporated

// All Rights Reserved.

//

// NOTICE:  Adobe permits you to use, modify, and distribute this file in

// accordance with the terms of the Adobe license agreement accompanying it.

/*****************************************************************************/

/* $Id: //mondo/dng_sdk_1_4/dng_sdk/source/dng_date_time.h#1 $ */ 

/* $DateTime: 2012/05/30 13:28:51 $ */

/* $Change: 832332 $ */

/* $Author: tknoll $ */

/** \file

 * Functions and classes for working with dates and times in DNG files.

 */

/*****************************************************************************/

#ifndef __dng_date_time__

#define __dng_date_time__

/*****************************************************************************/

#include "dng_classes.h"

#include "dng_string.h"

#include "dng_types.h"

/*****************************************************************************/

/// \brief Class for holding a date/time and converting to and from relevant

/// date/time formats

class dng_date_time

  {

  public:

    uint32 fYear;

    uint32 fMonth;

    uint32 fDay;

    uint32 fHour;

    uint32 fMinute;

    uint32 fSecond;

  public:

    /// Construct an invalid date/time

    dng_date_time ();

    /// Construct a date/time with specific values.

    /// \param year Year to use as actual integer value, such as 2006.

    /// \param month Month to use from 1 - 12, where 1 is January.

    /// \param day Day of month to use from 1 -31, where 1 is the first.

    /// \param hour Hour of day to use from 0 - 23, where 0 is midnight.

    /// \param minute Minute of hour to use from 0 - 59.

    /// \param second Second of minute to use from 0 - 59.

    dng_date_time (uint32 year,

             uint32 month,

             uint32 day,

             uint32 hour,

             uint32 minute,

             uint32 second);

    /// Predicate to determine if a date is valid.

    /// \retval true if all fields are within range.

    bool IsValid () const;

    /// Predicate to determine if a date is invalid.

    /// \retval true if any field is out of range.

    bool NotValid () const

      {

      return !IsValid ();

      }

    /// Equal operator.

    bool operator== (const dng_date_time &dt) const

      {

      return fYear   == dt.fYear   &&

           fMonth  == dt.fMonth  &&

           fDay    == dt.fDay    &&

           fHour   == dt.fHour   &&

           fMinute == dt.fMinute &&

           fSecond == dt.fSecond;

      }

    // Not-equal operator.

    bool operator!= (const dng_date_time &dt) const

      {

      return !(*this == dt);

      }

    /// Set date to an invalid value.

    void Clear ();

    /// Parse an EXIF format date string.

    /// \param s Input date string to parse.

    /// \retval true if date was parsed successfully and date is valid.

    bool Parse (const char *s);

  };

/*****************************************************************************/

/// \brief Class for holding a time zone.

class dng_time_zone

  {

  private:

    enum

      {

      kMaxOffsetHours = 15,

      kMinOffsetHours = -kMaxOffsetHours,

      kMaxOffsetMinutes = kMaxOffsetHours * 60,

      kMinOffsetMinutes = kMinOffsetHours * 60,

      kInvalidOffset = kMinOffsetMinutes - 1

      };

    // Offset from GMT in minutes.  Positive numbers are

    // ahead of GMT, negative number are behind GMT.

    int32 fOffsetMinutes;

  public:

    dng_time_zone ()

      : fOffsetMinutes (kInvalidOffset)

      {

      }

    void Clear ()

      {

      fOffsetMinutes = kInvalidOffset;

      }

    void SetOffsetHours (int32 offset)

      {

      fOffsetMinutes = SafeInt32Mult(offset, 60);

      }

    void SetOffsetMinutes (int32 offset)

      {

      fOffsetMinutes = offset;

      }

    void SetOffsetSeconds (int32 offset)

      {

      fOffsetMinutes = (offset > 0) ? ((offset + 30) / 60)

                      : ((offset - 30) / 60);

      }

    bool IsValid () const

      {

      return fOffsetMinutes >= kMinOffsetMinutes &&

           fOffsetMinutes <= kMaxOffsetMinutes;

      }

    bool NotValid () const

      {

      return !IsValid ();

      }

    int32 OffsetMinutes () const

      {

      return fOffsetMinutes;

      }

    bool IsExactHourOffset () const

      {

      return IsValid () && ((fOffsetMinutes % 60) == 0);

      }

    int32 ExactHourOffset () const

      {

      return fOffsetMinutes / 60;

      }

    dng_string Encode_ISO_8601 () const;

  };

/*****************************************************************************/

/// \brief Class for holding complete data/time/zone information.

class dng_date_time_info

  {

  private:

    // Is only the date valid and not the time? 

    bool fDateOnly;

    // Date and time.

    dng_date_time fDateTime;

    // Subseconds string (stored in a separate tag in EXIF).

    dng_string fSubseconds;

    // Time zone, if known.

    dng_time_zone fTimeZone;

  public:

    dng_date_time_info ();

    bool IsValid () const;

    bool NotValid () const

      {

      return !IsValid ();

      }

    void Clear ()

      {

      *this = dng_date_time_info ();

      }

    const dng_date_time & DateTime () const

      {

      return fDateTime;

      }

    void SetDateTime (const dng_date_time &dt)

      {

      fDateOnly = false;

      fDateTime = dt;

      }

    const dng_string & Subseconds () const

      {

      return fSubseconds;

      }

    void SetSubseconds (const dng_string &s)

      {

      fSubseconds = s;

      }

    const dng_time_zone & TimeZone () const

      {

      return fTimeZone;

      }

    void SetZone (const dng_time_zone &zone)

      {

      fTimeZone = zone;

      }

    void Decode_ISO_8601 (const char *s);

    dng_string Encode_ISO_8601 () const;

    void Decode_IPTC_Date (const char *s);

    dng_string Encode_IPTC_Date () const;

    void Decode_IPTC_Time (const char *s);

    dng_string Encode_IPTC_Time () const;

  private:

    void SetDate (uint32 year,

            uint32 month,

            uint32 day);

    void SetTime (uint32 hour,

            uint32 minute,

            uint32 second);

  };

/*****************************************************************************/

/// Get the current date/time and timezone.

/// \param info Receives current data/time/zone.

void CurrentDateTimeAndZone (dng_date_time_info &info);

/*****************************************************************************/

/// Convert UNIX "seconds since Jan 1, 1970" time to a dng_date_time

void DecodeUnixTime (uint32 unixTime, dng_date_time &dt);

/*****************************************************************************/

/// Return timezone of current location at a given date.

/// \param dt Date at which to compute timezone difference. (For example, used 

/// to determine Daylight Savings, etc.)

/// \retval Time zone for date/time dt.

dng_time_zone LocalTimeZone (const dng_date_time &dt);

/*****************************************************************************/

/// Tag to encode date represenation format

enum dng_date_time_format

  {

  dng_date_time_format_unknown            = 0, /// Date format not known

  dng_date_time_format_exif               = 1, /// EXIF date string

  dng_date_time_format_unix_little_endian = 2, /// 32-bit UNIX time as 4-byte little endian

  dng_date_time_format_unix_big_endian    = 3  /// 32-bit UNIX time as 4-byte big endian

  };

/*****************************************************************************/

/// \brief Store file offset from which date was read.

///

/// Used internally by Adobe to update date in original file.

/// \warning Use at your own risk.

class dng_date_time_storage_info

  {

  private:

    uint64 fOffset;

    dng_date_time_format fFormat;

  public:

    /// The default constructor initializes to an invalid state.

    dng_date_time_storage_info ();

    /// Construct with file offset and date format.

    dng_date_time_storage_info (uint64 offset,

                  dng_date_time_format format);

    /// Predicate to determine if an offset is valid.

    /// \retval true if offset is valid.

    bool IsValid () const;

    // The accessors throw if the data is not valid.

    /// Getter for offset in file.

    /// \exception dng_exception with fErrorCode equal to dng_error_unknown

    /// if offset is not valid.

    uint64 Offset () const;

    /// Get for format date was originally stored in file. Throws a 

    /// dng_error_unknown exception if offset is invalid.

    /// \exception dng_exception with fErrorCode equal to dng_error_unknown

    /// if offset is not valid.

    dng_date_time_format Format () const;

  };

/*****************************************************************************/

// Kludge: Global boolean to turn on fake time zones in XMP for old software.

extern bool gDNGUseFakeTimeZonesInXMP;

/*****************************************************************************/

#endif

/*****************************************************************************/