<?php 
// +-------------------------------------------------+
// © 2002-2014 PMB Services / www.sigb.net pmb@sigb.net et contributeurs (voir www.sigb.net)
// +-------------------------------------------------+
// $Id: map_holds_reducer.class.php,v 1.10 2019/07/10 06:44:08 btafforeau Exp $

if (stristr($_SERVER['REQUEST_URI'], ".class.php")) die("no access");


require_once($class_path."/map/map_hold_point.class.php");

class map_holds_reducer {
	

	/**
	 * Emprise de la carte
	 * @var map_hold_polygon
	 * @access protected
	 */
	protected $map_hold;
	
	/**
	 * Emprises des éléments à afficher sur la carte
	 * 
	 * @access protected
	 */
	protected $holds;
	
	/**
	 * Box des emprises des éléments à afficher sur la carte
	 *
	 * @access protected
	 */
	protected $holds_box;	
	
	protected $map_area;
	
	protected $clusters;
	
	protected $map_distance;
	
	protected $displayed_holds;
	
	protected $clustered_holds;
	/**
	 * Constructeur
	 *  @param map_hold_polygon map_hold Emprise courante de la carte
	 *  @param Array() ids Liste des identifiants des objets
	 *  @param int hold_max Nombre maximum d'emprise présentes sur une couche de la carte
	
	 * @return void
	 */
	
	public function __construct($map_hold,$holds) {
		$this->map_hold = $map_hold;
		$this->holds = $holds;
		$this->clusters = array();
		if(is_object($this->map_hold)) {
			$this->init();
			$this->map_hold->get_coords();
		}
	}
	
	
	public function init(){
		global $opac_map_hold_distance;
		
		$query = "select Area(geomfromtext('".$this->map_hold->get_wkt()."')) as area";
		$result = pmb_mysql_query($query);
		if(pmb_mysql_num_rows($result)){
			$row = pmb_mysql_fetch_object($result);
			$this->map_area = $row->area;
		}
		$map_coords = $this->map_hold->get_coords();
		/**
		 * La fonction SQL enveloppe renvoi une emprise normalisée telle que: POLYGON((MINX MINY, MAXX MINY, MAXX MAXY, MINX MAXY, MINX MINY))
		 * La distance mini se trouve donc entre les points 0 et 3 (le point 4 étant le point de fermeture du polygone)
		 */
		$this->map_distance = (sqrt(pow(($map_coords[0]->get_decimal_long() - $map_coords[3]->get_decimal_long()),2) + pow(($map_coords[0]->get_decimal_lat() - $map_coords[3]->get_decimal_lat()),2)))/$opac_map_hold_distance;
	}
	
	/**
	 * Retourne les emprises correspondantes à la réduction
	 *  @param int hold_max Nombre maximum d'emprise présentes sur une couche de la carte
	
	 * @return void
	 */
	public function get_reduction(){
		global $opac_map_hold_ratio_max, $opac_map_hold_ratio_min;

		$this->dicho($opac_map_hold_ratio_min, $opac_map_hold_ratio_max);
		
		
		foreach($this->clustered_holds as $key => $hold){
			$clustered = false;
			if(!count($this->clusters)){
				$this->clusters[$key] = $hold;
			}else{
				foreach($this->clusters as $keyC => $holdC){
					if($this->shouldCluster($holdC, $hold)){
						if(is_array($holdC->get_num_object())){
							$num_obj = $holdC->get_num_object();
 							if(!in_array($hold->get_num_object(), $num_obj)){
								$num_obj[] = $hold->get_num_object();
								$holdC->set_num_object($num_obj);
 							}
						}else{
							if($holdC->get_num_object() != $hold->get_num_object()){
								$holdC->set_num_object(array($holdC->get_num_object(), $hold->get_num_object()));
							}
						}
						$clustered = true;
						break;
					}
				}
				if(!$clustered){
					$this->clusters[$key] = $hold;
				}
			}
		}
		
		foreach($this->clusters as $key => $hold){
			$wkt = $hold->get_center();
			$this->clusters[$key] = new map_hold_point("point", $hold->get_num_object());
			$this->clusters[$key]->set_wkt($wkt);
		}
  
		uasort($this->displayed_holds, array('self', 'cmp_area'));
		return array_merge($this->displayed_holds, $this->clusters);
	} 
	
	public function get_occupation_percentage($hold){
            return ($hold->get_normalized_bbox_area()/$this->map_area)*100;
	}
	
	public function get_point_center($hold){
		global $dbh;
		$query = "select AsText(Centroid(geomfromtext('".$hold->get_wkt()."'))) as center";	
		$result = pmb_mysql_query($query, $dbh);
		if(pmb_mysql_num_rows($result)){
			$row = pmb_mysql_fetch_object($result);
			$hold_wkt = $row->center;
			return $hold_wkt;
		}
	}
	
	public function shouldCluster($cluster, $hold){
		$coords_cluster = explode(" ",substr($cluster->get_center(),strpos($cluster->get_center(),"(")+1,-1));
		$coords_hold = explode(" ",substr($hold->get_center(),strpos($hold->get_center(),"(")+1,-1));
		
		$distance = sqrt(pow(($coords_cluster[0] - $coords_hold[0]),2) + pow(($coords_cluster[1] - $coords_hold[1]),2));	
		return ($distance <= $this->map_distance);
	}
	
	public function check_wkt($holds, $wkt_string){
		foreach($holds as $num => $hold){
			if($hold->get_wkt() == $wkt_string){
				return $num;
			}
		}
		return false;
	}
	
	public function simplify_polygon($wkt){
		$parts = explode(',', $wkt);
		$new = "";
		$start = array_shift($parts);
		$stop = array_pop($parts);
		for($j=0 ; $j<=count($parts) ; $j++){
			if($j % 2)
				$new.= ",".$parts[$j];
		}
		if(!(count($parts) % 2)){
			$new.=",";
		}
		$wkt = $start.$new.$stop;
		return $wkt;
	}
	
	public function dicho($min, $max){
		global $opac_map_max_holds, $opac_map_hold_ratio_min;
		$params = explode(",", $opac_map_max_holds);
		if($params[1] == "1" && count($this->holds)>$params[0]){
			$min = $max;
		}
		//print " min ".$min." max ".$max;
		$nb_emprise_min = $this->calc_empr($min);
		$nb_emprise_max = $this->calc_empr($max);
		
		if($nb_emprise_max >= $params[0]){
			//Avec le seuil max, on a déjà trop d'emprise, on ne continue pas.
			return;
		}
		if($nb_emprise_min <= $params[0]){
			$this->calc_empr($min);
			//On a un nombre convenable d'emprise avec le seuil min, on s'arrête
			return;
		}
		
		$mid = (($max-$min)/2)+$min;
		if((($max-$min)/2)  <= $opac_map_hold_ratio_min){
			$this->calc_empr($mid);
			//On s'arrête car le seuil est inférieur au seuil mini
			return;
		}
		$nb_emprise_seuil = $this->calc_empr($mid);
		if($nb_emprise_seuil < $params[0]){
			return $this->dicho($min, $mid);
		}else if($nb_emprise_seuil == $params[0]){
			return;
		}else{
			return $this->dicho($mid, $max);
		}
	}
	
  	public function calc_empr($seuil_min){
            
            $this->displayed_holds = array();
            $this->clusters = array();
            $this->clustered_holds=$this->holds;
            return array();
	}
   /*     
	public function calc_empr($seuil_min){
		global $opac_map_hold_ratio_max;
                
		$this->displayed_holds = array();
		$this->clustered_holds = array();
		$this->clusters = array();
		foreach($this->holds as $key => $hold){
			if($this->get_occupation_percentage($hold) > $seuil_min){//ces emprises doivent être affichées
                                //quand il y a une seule emprise, $this->get_occupation_percentage($hold) renvoie 100
				if ($this->get_occupation_percentage($hold) < $opac_map_hold_ratio_max || count($this->holds) == 1){ 
					$existant_key = $this->check_wkt($this->displayed_holds, $hold->get_wkt());
					if($existant_key != false){
						if(is_array($this->displayed_holds[$existant_key]->get_num_object())){
							$num_obj = $this->displayed_holds[$existant_key]->get_num_object();
							$num_obj[] = $hold->get_num_object();
							$this->displayed_holds[$existant_key]->set_num_object($num_obj);
						}else{
							$this->displayed_holds[$existant_key]->set_num_object(array($this->displayed_holds[$existant_key]->get_num_object(), $hold->get_num_object()));
						}
					}else{
						$this->displayed_holds[$key] = $hold;
						if(count($this->displayed_holds[$key]->get_wkt())>1000 && $this->displayed_holds[$key]->get_hold_type()=="POLYGON"){
							$this->displayed_holds[$key]->set_wkt($this->simplify_polygon($this->displayed_holds[$key]->get_wkt()));
						}
					}
				}//Trop grandes non affichées
			}else{//celles ci doivent etre reduite a un point
				$this->clustered_holds[$key] = $hold;
			}
		}
		return count($this->displayed_holds);
	}
    */
     
	public static function cmp_area($a, $b) {
		if ($a->get_normalized_bbox_area() == $b->get_normalized_bbox_area()) {
			return 0;
		}
		return ($a->get_normalized_bbox_area() > $b->get_normalized_bbox_area()) ? -1 : 1;
	}
}