// initialize values
$baseDate = new Zend_Date();
$dateDeb = new Zend_Date('maValeurDeDebut');
$dateFin = new Zend_Date('maValeurDeFin');

while($dateDeb <= $dateFin)
{
	// add values for the week
	$baseDate->setDate($dateDeb);
	$baseDate->subDay($baseDate->get(Zend_Date::WEEKDAY_8601)-1);			 // get day of the week and go on the first day
	if (!in_array($baseDate->toString('yyyy-MM-dd'), $listeWeeks)) {
		$listeWeeks[]['start'] = $baseDate->toString('yyyy-MM-dd');			 // first day of the week
		$listeWeeks[]['end'] = $baseDate->addDay(6)->toString('yyyy-MM-dd'); // last day of the week
		$listeWeeks[]['number'] = $baseDate->get(Zend_Date::WEEK);			 // week number
	}
	// increment day
	$dateDeb->addDay(1);
}

// DATE DE DEBUT
	////////////////////////////////////////
	// Timestamp de la 1e date
	$datedebut = explode("-",$datedebut);
	$TIME_datedebut = mktime (0,0,0,$datedebut[1],$datedebut[2],$datedebut[0]);
	// Numéro du jour de la 1ère date d'activité
	$jourdebut	= (int) date('w', $TIME_datedebut);
	////////////////////////////////////////
	
	
	
	////////////////////
	// DATE FIN
	////////////////////
	// Date actuelle (date fin)
	$datefin=date('Y-m-d');
	$datefin = explode("-",$datefin);
	$TIME_datefin = time();
	// Numéro du jour de la date du jour
	$jourfin	= (int) date('w', $TIME_datefin);
	////////////////////////////////////////
 
 
 
	////////////////////
	// ECART EN JOUR ENTRE LES DEUX DATES
	////////////////////
	// on calcule le nombre de secondes d'écart entre les deux dates
	$ecart_secondes =  $TIME_datefin - $TIME_datedebut;
	// puis on tranforme en jours (arrondi inférieur)
	$ecart_jours = floor($ecart_secondes / (60*60*24));
	$ecart_jours =$ecart_jours+1;
	echo "$ecart_jours<BR>";
	////////////////////////////////////////

// 1e semaine
	
		if($jourdebut=="0")
		{$diff="6";$enlev0="1";}
		elseif($jourdebut=="1")
		{$diff="0";$enlev0="7";}
		elseif($jourdebut=="2")
		{$diff="1";$enlev0="6";}
		elseif($jourdebut=="3")
		{$diff="2";$enlev0="5";}
		elseif($jourdebut=="4")
		{$diff="3";$enlev0="4";}
		elseif($jourdebut=="5")
		{$diff="4";$enlev0="3";}
		elseif($jourdebut=="6")
		{$diff="5";$enlev0="2";}
		
		
		$date_debut_semaine_1 = mktime(date("H"), date("i"), date("s"), $datedebut[1], $datedebut[2]-$diff, $datedebut[0]);
		$date_debut_semaine_1= date('Y-m-d', $date_debut_semaine_1);
		$date_debut_semaine_1 = explode("-",$date_debut_semaine_1);
		
		$date_fin_semaine_1 = mktime(date("H"), date("i"), date("s"), $date_debut_semaine_1[1], $date_debut_semaine_1[2]+6, $date_debut_semaine_1[0]);
		$date_fin_semaine_1= date('Y-m-d', $date_fin_semaine_1);
		$date_fin_semaine_1 = explode("-",$date_fin_semaine_1);
	
		echo "$date_debut_semaine_1[2]/$date_debut_semaine_1[1]/$date_debut_semaine_1[0]  $date_fin_semaine_1[2]/$date_fin_semaine_1[1]/$date_fin_semaine_1[0]<BR>";
		
		
		// Dernière semaine
	
		if($jourfin=="0")
		{$diff="6";$enlev="7";}
		elseif($jourfin=="1")
		{$diff="0";$enlev="1";}
		elseif($jourfin=="2")
		{$diff="1";$enlev="2";}
		elseif($jourfin=="3")
		{$diff="2";$enlev="3";}
		elseif($jourfin=="4")
		{$diff="3";$enlev="4";}
		elseif($jourfin=="5")
		{$diff="4";$enlev="5";}
		elseif($jourfin=="6")
		{$diff="5";$enlev="6";}
		$ecart_jours2=$ecart_jours-$enlev0-$enlev;
		
		$date_debut_semaine_derniere = mktime(date("H"), date("i"), date("s"), $datefin[1], $datefin[2]-$diff, $datefin[0]);
		$date_debut_semaine_derniere= date('Y-m-d', $date_debut_semaine_derniere);
		$date_debut_semaine_derniere = explode("-",$date_debut_semaine_derniere);
		
		$date_fin_semaine_derniere = mktime(date("H"), date("i"), date("s"), $date_debut_semaine_derniere[1], $date_debut_semaine_derniere[2]+6, $date_debut_semaine_derniere[0]);
		$date_fin_semaine_derniere= date('Y-m-d', $date_fin_semaine_derniere);
		$date_fin_semaine_derniere = explode("-",$date_fin_semaine_derniere);
	
		echo "$date_debut_semaine_derniere[2]/$date_debut_semaine_derniere[1]/$date_debut_semaine_derniere[0]  $date_fin_semaine_derniere[2]/$date_fin_semaine_derniere[1]/$date_fin_semaine_derniere[0]<BR>";