Changes to Date/Time conversion functions to use DateTime objects internally rather than unix timestamps;

Changes to Date/Time methods to make them more intuitive and correct (eg `excelToTimestamp` rather than `excelToPHP`)
TODO - Still need to write unit tests, and convert Examples to use the new names

src/PhpSpreadsheet/Calculation/DateTime.php

@@ -123,7 +123,7 @@ class DateTime
     private static function adjustDateByMonths($dateValue = 0, $adjustmentMonths = 0)
     {
         // Execute function
-        $PHPDateObject = \PHPExcel\Shared\Date::excelToPHPObject($dateValue);
+        $PHPDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($dateValue);
         $oMonth = (int) $PHPDateObject->format('m');
         $oYear = (int) $PHPDateObject->format('Y');
 
@@ -218,10 +218,10 @@ class DateTime
                 $retValue = (float) $excelDateTime;
                 break;
             case Functions::RETURNDATE_PHP_NUMERIC:
-                $retValue = (integer) \PHPExcel\Shared\Date::excelToPHP($excelDateTime);
+                $retValue = (integer) \PHPExcel\Shared\Date::excelToTimestamp($excelDateTime);
                 break;
             case Functions::RETURNDATE_PHP_OBJECT:
-                $retValue = \PHPExcel\Shared\Date::excelToPHPObject($excelDateTime);
+                $retValue = \PHPExcel\Shared\Date::excelToDateTimeObject($excelDateTime);
                 break;
         }
         date_default_timezone_set($saveTimeZone);
@@ -341,9 +341,9 @@ class DateTime
             case Functions::RETURNDATE_EXCEL:
                 return (float) $excelDateValue;
             case Functions::RETURNDATE_PHP_NUMERIC:
-                return (integer) \PHPExcel\Shared\Date::excelToPHP($excelDateValue);
+                return (integer) \PHPExcel\Shared\Date::excelToTimestamp($excelDateValue);
             case Functions::RETURNDATE_PHP_OBJECT:
-                return \PHPExcel\Shared\Date::excelToPHPObject($excelDateValue);
+                return \PHPExcel\Shared\Date::excelToDateTimeObject($excelDateValue);
         }
     }
 
@@ -435,7 +435,7 @@ class DateTime
                 }
                 return (float) \PHPExcel\Shared\Date::formattedPHPToExcel($calendar, 1, $date, $hour, $minute, $second);
             case Functions::RETURNDATE_PHP_NUMERIC:
-                return (integer) \PHPExcel\Shared\Date::excelToPHP(\PHPExcel\Shared\Date::formattedPHPToExcel(1970, 1, 1, $hour, $minute, $second));    // -2147468400; //    -2147472000 + 3600
+                return (integer) \PHPExcel\Shared\Date::excelToTimestamp(\PHPExcel\Shared\Date::formattedPHPToExcel(1970, 1, 1, $hour, $minute, $second));    // -2147468400; //    -2147472000 + 3600
             case Functions::RETURNDATE_PHP_OBJECT:
                 $dayAdjust = 0;
                 if ($hour < 0) {
@@ -584,7 +584,7 @@ class DateTime
                 case Functions::RETURNDATE_EXCEL:
                     return (float) $excelDateValue;
                 case Functions::RETURNDATE_PHP_NUMERIC:
-                    return (integer) \PHPExcel\Shared\Date::excelToPHP($excelDateValue);
+                    return (integer) \PHPExcel\Shared\Date::excelToTimestamp($excelDateValue);
                 case Functions::RETURNDATE_PHP_OBJECT:
                     return new \DateTime($PHPDateArray['year'].'-'.$PHPDateArray['month'].'-'.$PHPDateArray['day'].' 00:00:00');
             }
@@ -645,7 +645,7 @@ class DateTime
                 case Functions::RETURNDATE_EXCEL:
                     return (float) $excelDateValue;
                 case Functions::RETURNDATE_PHP_NUMERIC:
-                    return (integer) $phpDateValue = \PHPExcel\Shared\Date::excelToPHP($excelDateValue+25569) - 3600;
+                    return (integer) $phpDateValue = \PHPExcel\Shared\Date::excelToTimestamp($excelDateValue+25569) - 3600;
                 case Functions::RETURNDATE_PHP_OBJECT:
                     return new \DateTime('1900-01-01 '.$PHPDateArray['hour'].':'.$PHPDateArray['minute'].':'.$PHPDateArray['second']);
             }
@@ -685,12 +685,12 @@ class DateTime
         // Execute function
         $difference = $endDate - $startDate;
 
-        $PHPStartDateObject = \PHPExcel\Shared\Date::excelToPHPObject($startDate);
+        $PHPStartDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($startDate);
         $startDays = $PHPStartDateObject->format('j');
         $startMonths = $PHPStartDateObject->format('n');
         $startYears = $PHPStartDateObject->format('Y');
 
-        $PHPEndDateObject = \PHPExcel\Shared\Date::excelToPHPObject($endDate);
+        $PHPEndDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($endDate);
         $endDays = $PHPEndDateObject->format('j');
         $endMonths = $PHPEndDateObject->format('n');
         $endYears = $PHPEndDateObject->format('Y');
@@ -805,12 +805,12 @@ class DateTime
         }
 
         // Execute function
-        $PHPStartDateObject = \PHPExcel\Shared\Date::excelToPHPObject($startDate);
+        $PHPStartDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($startDate);
         $startDay = $PHPStartDateObject->format('j');
         $startMonth = $PHPStartDateObject->format('n');
         $startYear = $PHPStartDateObject->format('Y');
 
-        $PHPEndDateObject = \PHPExcel\Shared\Date::excelToPHPObject($endDate);
+        $PHPEndDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($endDate);
         $endDay = $PHPEndDateObject->format('j');
         $endMonth = $PHPEndDateObject->format('n');
         $endYear = $PHPEndDateObject->format('Y');
@@ -1112,9 +1112,9 @@ class DateTime
             case Functions::RETURNDATE_EXCEL:
                 return (float) $endDate;
             case Functions::RETURNDATE_PHP_NUMERIC:
-                return (integer) \PHPExcel\Shared\Date::excelToPHP($endDate);
+                return (integer) \PHPExcel\Shared\Date::excelToTimestamp($endDate);
             case Functions::RETURNDATE_PHP_OBJECT:
-                return \PHPExcel\Shared\Date::excelToPHPObject($endDate);
+                return \PHPExcel\Shared\Date::excelToDateTimeObject($endDate);
         }
     }
 
@@ -1147,7 +1147,7 @@ class DateTime
         }
 
         // Execute function
-        $PHPDateObject = \PHPExcel\Shared\Date::excelToPHPObject($dateValue);
+        $PHPDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($dateValue);
 
         return (int) $PHPDateObject->format('j');
     }
@@ -1191,7 +1191,7 @@ class DateTime
         }
 
         // Execute function
-        $PHPDateObject = \PHPExcel\Shared\Date::excelToPHPObject($dateValue);
+        $PHPDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($dateValue);
         $DoW = $PHPDateObject->format('w');
 
         $firstDay = 1;
@@ -1267,7 +1267,7 @@ class DateTime
         }
 
         // Execute function
-        $PHPDateObject = \PHPExcel\Shared\Date::excelToPHPObject($dateValue);
+        $PHPDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($dateValue);
         $dayOfYear = $PHPDateObject->format('z');
         $PHPDateObject->modify('-' . $dayOfYear . ' days');
         $dow = $PHPDateObject->format('w');
@@ -1306,7 +1306,7 @@ class DateTime
         }
 
         // Execute function
-        $PHPDateObject = \PHPExcel\Shared\Date::excelToPHPObject($dateValue);
+        $PHPDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($dateValue);
 
         return (int) $PHPDateObject->format('n');
     }
@@ -1338,7 +1338,7 @@ class DateTime
         }
 
         // Execute function
-        $PHPDateObject = \PHPExcel\Shared\Date::excelToPHPObject($dateValue);
+        $PHPDateObject = \PHPExcel\Shared\Date::excelToDateTimeObject($dateValue);
 
         return (int) $PHPDateObject->format('Y');
     }
@@ -1379,7 +1379,7 @@ class DateTime
         } elseif ($timeValue < 0.0) {
             return Functions::NAN();
         }
-        $timeValue = \PHPExcel\Shared\Date::excelToPHP($timeValue);
+        $timeValue = \PHPExcel\Shared\Date::excelToTimestamp($timeValue);
 
         return (int) gmdate('G', $timeValue);
     }
@@ -1420,7 +1420,7 @@ class DateTime
         } elseif ($timeValue < 0.0) {
             return Functions::NAN();
         }
-        $timeValue = \PHPExcel\Shared\Date::excelToPHP($timeValue);
+        $timeValue = \PHPExcel\Shared\Date::excelToTimestamp($timeValue);
 
         return (int) gmdate('i', $timeValue);
     }
@@ -1461,7 +1461,7 @@ class DateTime
         } elseif ($timeValue < 0.0) {
             return Functions::NAN();
         }
-        $timeValue = \PHPExcel\Shared\Date::excelToPHP($timeValue);
+        $timeValue = \PHPExcel\Shared\Date::excelToTimestamp($timeValue);
 
         return (int) gmdate('s', $timeValue);
     }
@@ -1507,7 +1507,7 @@ class DateTime
             case Functions::RETURNDATE_EXCEL:
                 return (float) \PHPExcel\Shared\Date::PHPToExcel($PHPDateObject);
             case Functions::RETURNDATE_PHP_NUMERIC:
-                return (integer) \PHPExcel\Shared\Date::excelToPHP(\PHPExcel\Shared\Date::PHPToExcel($PHPDateObject));
+                return (integer) \PHPExcel\Shared\Date::excelToTimestamp(\PHPExcel\Shared\Date::PHPToExcel($PHPDateObject));
             case Functions::RETURNDATE_PHP_OBJECT:
                 return $PHPDateObject;
         }
@@ -1556,7 +1556,7 @@ class DateTime
             case Functions::RETURNDATE_EXCEL:
                 return (float) \PHPExcel\Shared\Date::PHPToExcel($PHPDateObject);
             case Functions::RETURNDATE_PHP_NUMERIC:
-                return (integer) \PHPExcel\Shared\Date::excelToPHP(\PHPExcel\Shared\Date::PHPToExcel($PHPDateObject));
+                return (integer) \PHPExcel\Shared\Date::excelToTimestamp(\PHPExcel\Shared\Date::PHPToExcel($PHPDateObject));
             case Functions::RETURNDATE_PHP_OBJECT:
                 return $PHPDateObject;
         }

src/PhpSpreadsheet/Calculation/Financial.php

@@ -67,7 +67,7 @@ class Financial
     {
         $months = 12 / $frequency;
 
-        $result = \PHPExcel\Shared\Date::excelToPHPObject($maturity);
+        $result = \PHPExcel\Shared\Date::excelToDateTimeObject($maturity);
         $eom = self::isLastDayOfMonth($result);
 
         while ($settlement < \PHPExcel\Shared\Date::PHPToExcel($result)) {

src/PhpSpreadsheet/Shared/Date.php

@@ -33,50 +33,23 @@ class Date
     const CALENDAR_WINDOWS_1900 = 1900;        //    Base date of 1st Jan 1900 = 1.0
     const CALENDAR_MAC_1904 = 1904;            //    Base date of 2nd Jan 1904 = 1.0
 
-    /*
-     * Names of the months of the year, indexed by shortname
-     * Planned usage for locale settings
-     *
-     * @public
-     * @var    string[]
-     */
-    public static $monthNames = [
-        'Jan' => 'January',
-        'Feb' => 'February',
-        'Mar' => 'March',
-        'Apr' => 'April',
-        'May' => 'May',
-        'Jun' => 'June',
-        'Jul' => 'July',
-        'Aug' => 'August',
-        'Sep' => 'September',
-        'Oct' => 'October',
-        'Nov' => 'November',
-        'Dec' => 'December',
-    ];
-
-    /*
-     * Names of the months of the year, indexed by shortname
-     * Planned usage for locale settings
-     *
-     * @public
-     * @var    string[]
-     */
-    public static $numberSuffixes = [
-        'st',
-        'nd',
-        'rd',
-        'th',
-    ];
-
     /*
      * Base calendar year to use for calculations
+     * Value is either CALENDAR_WINDOWS_1900 (1900) or CALENDAR_MAC_1904 (1904)
      *
      * @private
      * @var    int
      */
     protected static $excelBaseDate = self::CALENDAR_WINDOWS_1900;
 
+    /*
+     * Default timezone to use for DateTime objects
+     *
+     * @private
+     * @var    null|\DateTimeZone
+     */
+    protected static $defaultTimeZone;
+
     /**
      * Set the Excel calendar (Windows 1900 or Mac 1904)
      *
@@ -87,13 +60,12 @@ class Date
     {
         if (($baseDate == self::CALENDAR_WINDOWS_1900) ||
             ($baseDate == self::CALENDAR_MAC_1904)) {
-            self::$excelBaseDate = $baseDate;
+            self::$excelCalendar = $baseDate;
             return true;
         }
         return false;
     }
 
-
     /**
      * Return the Excel calendar (Windows 1900 or Mac 1904)
      *
@@ -101,73 +73,95 @@ class Date
      */
     public static function getExcelCalendar()
     {
-        return self::$excelBaseDate;
+        return self::$excelCalendar;
     }
 
+    /**
+     * Set the Default timezone to use for dates
+     *
+     * @param     string|\DateTimeZone    $timezone    The timezone to set for all Excel datetimestamp to PHP DateTime Object conversions
+     * @return    boolean                              Success or failure
+     * @throws    \Exception
+     */
+    public static function setDefaultTimezone($timeZone)
+    {
+        if ($timeZone = self::validateTimeZone($timeZone)) {
+            self::$defaultTimeZone = $timeZone;
+            return true;
+        }
+        return false;
+    }
 
     /**
-     *    Convert a date from Excel to PHP
+     * Return the Default timezone being used for dates
      *
-     *    @param        integer        $dateValue            Excel date/time value
+     * @return     \DateTimeZone    The timezone being used as default for Excel timestamp to PHP DateTime object
-     *    @param        boolean        $adjustToTimezone    Flag indicating whether $dateValue should be treated as
-     *                                                    a UST timestamp, or adjusted to UST
-     *    @param        string         $timezone            The timezone for finding the adjustment from UST
-     *    @return       integer        PHP serialized date/time
      */
-    public static function excelToPHP($dateValue = 0, $adjustToTimezone = false, $timezone = null)
+    public static function getDefaultTimezone()
     {
+        if (self::$defaultTimeZone === null) {
+            self::$defaultTimeZone = new \DateTimeZone('UTC');
+        }
+        return self::$defaultTimeZone;
+    }
+
+    /**
+     * Validate a timezone
+     *
+     * @param     string|\DateTimeZone    $timezone    The timezone to validate, either as a timezone string or object
+     * @return    \DateTimeZone                        The timezone as a timezone object
+     * @throws    \Exception
+     */
+    protected static function validateTimeZone($timeZone) {
+        if (is_object($timeZone) && $timeZone instanceof \DateTimeZone) {
+            return $timeZone;
+        } elseif (is_string($timeZone)) {
+            return new \DateTimeZone($timeZone);
+        }
+        throw new \Exception('Invalid timezone');
+    }
+
+    /**
+     * Convert a MS serialized datetime value from Excel to a PHP Date/Time object
+     *
+     * @param     integer|float    $dateValue        Excel date/time value
+     * @param     \DateTimeZone|string|null          $timezone            The timezone to assume for the Excel timestamp,
+     *                                                                        if you don't want to treat it as a UTC value
+     * @return    \DateTime                          PHP date/time object
+     * @throws    \Exception
+     */
+	public static function excelToDateTimeObject($excelTimestamp = 0, $timeZone = null) {
+        $timeZone = ($timeZone === null) ? self::getDefaultTimezone() : self::validateTimeZone($timeZone);
         if (self::$excelBaseDate == self::CALENDAR_WINDOWS_1900) {
-            $myexcelBaseDate = 25569;
+            $baseDate = ($excelTimestamp < 60) ? new \DateTime('1899-12-31', $timeZone) : new \DateTime('1899-12-30', $timeZone);
-            //    Adjust for the spurious 29-Feb-1900 (Day 60)
-            if ($dateValue < 60) {
-                --$myexcelBaseDate;
-            }
         } else {
-            $myexcelBaseDate = 24107;
+            $baseDate = new \DateTime('1904-01-01', $timeZone);
         }
+		$days = floor($excelTimestamp);
+        $partDay = $excelTimestamp - $days;
+        $hours = floor($partDay * 24);
+        $partDay = $partDay * 24 - $hours;
+        $minutes = floor($partDay * 60);
+        $partDay = $partDay * 60 - $minutes;
+        $seconds = floor($partDay * 60);
+//        $fraction = $partDay - $seconds;
 
-        // Perform conversion
+        $interval = '+' . $days . ' days';
-        if ($dateValue >= 1) {
+		return $baseDate->modify($interval)
-            $utcDays = $dateValue - $myexcelBaseDate;
+            ->setTime($hours, $minutes, $seconds);
-            $returnValue = round($utcDays * 86400);
+	}
-            if (($returnValue <= PHP_INT_MAX) && ($returnValue >= -PHP_INT_MAX)) {
-                $returnValue = (integer) $returnValue;
-            }
-        } else {
-            $hours = round($dateValue * 24);
-            $mins = round($dateValue * 1440) - round($hours * 60);
-            $secs = round($dateValue * 86400) - round($hours * 3600) - round($mins * 60);
-            $returnValue = (integer) gmmktime($hours, $mins, $secs);
-        }
-
-        $timezoneAdjustment = ($adjustToTimezone) ?
-            TimeZone::getTimezoneAdjustment($timezone, $returnValue) :
-            0;
-
-        return $returnValue + $timezoneAdjustment;
-    }
-
 
     /**
-     * Convert a date from Excel to a PHP Date/Time object
+     * Convert a MS serialized datetime value from Excel to a unix timestamp
      *
-     * @param    integer        $dateValue        Excel date/time value
+     * @param     integer|float    $dateValue        Excel date/time value
-     * @return   \DateTime                    PHP date/time object
+     * @return    integer                            Unix timetamp for this date/time
+     * @throws    \Exception
      */
-    public static function excelToPHPObject($dateValue = 0)
+	public static function excelToTimestamp($excelTimestampexcelTimestamp = 0, $timeZone = null) {
-    {
+	    return self::excelToTimestamp($excelTimestamp, $timeZone)
-        $dateTime = self::excelToPHP($dateValue);
+            ->format('U');
-        $days = floor($dateTime / 86400);
+	}
-        $time = round((($dateTime / 86400) - $days) * 86400);
-        $hours = round($time / 3600);
-        $minutes = round($time / 60) - ($hours * 60);
-        $seconds = round($time) - ($hours * 3600) - ($minutes * 60);
-
-        $dateObj = date_create('1-Jan-1970+'.$days.' days');
-        $dateObj->setTime($hours, $minutes, $seconds);
-
-        return $dateObj;
-    }
 
 
     /**

src/PhpSpreadsheet/Spreadsheet.php

@@ -1,4 +1,4 @@
-<?php
+<!----><?php
 
 namespace PHPExcel;
 
@@ -21,9 +21,9 @@ namespace PHPExcel;
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  *
- * @category   PHPExcel
+ * @category   PHPSpreadsheet
- * @package    PHPExcel
+ * @package    PHPSpreadsheet
- * @copyright  Copyright (c) 2006 - 2015 PHPExcel (http://www.codeplex.com/PHPExcel)
+ * @copyright  Copyright (c) 2006 PHPOffice (http://www.github.com/PHPOffice)
  * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt    LGPL
  * @version    ##VERSION##, ##DATE##
  */

src/PhpSpreadsheet/Style/NumberFormat.php

@@ -487,7 +487,7 @@ class NumberFormat extends Supervisor implements \PHPExcel\IComparable
         // escape any quoted characters so that DateTime format() will render them correctly
         $format = preg_replace_callback('/"(.*)"/U', ['self', 'escapeQuotesCallback'], $format);
 
-        $dateObj = \PHPExcel\Shared\Date::excelToPHPObject($value);
+        $dateObj = \PHPExcel\Shared\Date::excelToDateTimeObject($value);
         $value = $dateObj->format($format);
     }
 

src/PhpSpreadsheet/Worksheet/AutoFilter.php

@@ -327,7 +327,7 @@ class AutoFilter
         }
 
         if (is_numeric($cellValue)) {
-            $dateValue = \PHPExcel\Shared\Date::excelToPHP($cellValue);
+            $dateValue = \PHPExcel\Shared\Date::excelToTimestamp($cellValue);
             if ($cellValue < 1) {
                 //    Just the time part
                 $dtVal = date('His', $dateValue);
@@ -444,7 +444,7 @@ class AutoFilter
         }
 
         if (is_numeric($cellValue)) {
-            $dateValue = date('m', \PHPExcel\Shared\Date::excelToPHP($cellValue));
+            $dateValue = date('m', \PHPExcel\Shared\Date::excelToTimestamp($cellValue));
             if (in_array($dateValue, $monthSet)) {
                 return true;
             }