#include-once
#include <Date.au3>

; #FUNCTION# ====================================================================================================================
; Name ..........: _DateDiffAsApproxString
; Description ...: Returns a date diff in a human-readable format. Example: "2 months and 18 days"
; Syntax ........: _DateDiffAsApproxString($sDateOld, $sDateNew)
; Parameters ....: $sDateOld - The older date to diff.
;                  $sDateNew - The newer date to diff.
; Return values .: Success - Returns a string of approximate date difference.
;                  Failure - Returns an empty string an sets @error to 1.
; Author ........: orbs
; Modified ......:
; Remarks .......: The returned string is composed of only the first two most significant elements of difference.
;                  Both parameters should be specified in the standard AutoIt date format: "YYYY/MM/DD[ HH:MM:SS]"
; Related .......:
; Link ..........:
; Example .......: Yes
; ===============================================================================================================================
Func _DateDiffAsApproxString($sDateOld, $sDateNew)
	Local $aResult[2][2]
	Local $iResult = 0
	Local $nTemp = 0
	Local $aElement[6][2] = [['Y', 'year'],['M', 'month'],['D', 'day'],['h', 'hour'],['n', 'minute'],['s', 'second']]
	Local $iElement = 0
	For $iElement = 0 To 5
		If $iResult > 1 Then ExitLoop
		$nTemp = _DateDiff($aElement[$iElement][0], $sDateOld, $sDateNew)
		Select
			Case $nTemp <= 0
				ContinueLoop
			Case $nTemp = 1
				$aResult[$iResult][0] = 'a'
				If $iElement=3 Then $aResult[$iResult][0]&='n'
				$aResult[$iResult][1] = $aElement[$iElement][1]
			Case Else
				$aResult[$iResult][0] = $nTemp
				$aResult[$iResult][1] = $aElement[$iElement][1] & 's'
		EndSelect
		$iResult += 1
		$sDateOld = _DateAdd($aElement[$iElement][0], $nTemp, $sDateOld)
	Next
	Switch $iResult
		Case 1
			Return $aResult[0][0] & ' ' & $aResult[0][1]
		Case 2
			Return $aResult[0][0] & ' ' & $aResult[0][1] & ' and ' & $aResult[1][0] & ' ' & $aResult[1][1]
		Case Else
			Return SetError(1, 0, '')
	EndSwitch
EndFunc   ;==>_DateDiffAsApproxString