<?php

require_once(dirname(__FILE__).'/../constants.inc.php');

//

class PanoramaFormatException extends Exception {

        /** If the files organization is not correct for a panorama, we can't let it go...

         */

}

class site_point {

        /** Defines a point, with a panorama

         */

        private $base_dir;        // dir of tiles for that panorama

  private $name = false;

  private $prefix = false;

  private $params = false;

  private $zooms;

  public function __construct($dir) {

    // si $dir n'est pas un répertoire il ne s'agit pas d'un panorama.

          if (!is_dir($dir)) {

                  throw new PanoramaFormatException("$dir does not contain a panorama");

          }

    $this->base_dir = $dir;

    $this->prefix = basename($dir);

  }

  public function params_path() {

          return $this->base_dir.'/'.$this->prefix.'.params';

  }

  private function parse_and_cache_params() {

    if (is_file($this->params_path())) {

            $params = parse_ini_file($this->params_path());

            if ($params) {

                    $this->params = $params;

                    return $params;

            }

    }

    return array();

  }

  public function get_params() {

          // the params are cached

          if (isset($this->params) && $this->params) {

                  return $this->params;

          } else {

                  return $this->parse_and_cache_params();

          }

  }

  public function save_params() {

          $o = '';

          $p = $this->get_params();

          foreach ($this->get_params() as $k => $v) {

                  $o.= "$k = $v\n";

          }

          file_put_contents($this->params_path(), $o);

  }

  public function set_param($key, $value) {

          $p = $this->get_params();

          $this->params[$key] = $value;

          if ($key == 'titre') {

                  $this->name = $value;

          }

  }

  public function has_params(){

          $p = $this->get_params();

          return (isset($p['latitude'], $p['longitude'],

                        $p['altitude'], $p['titre']));

  }

  public function get_name() {

    return basename($this->base_dir);

  }

  public function get_prefix() {

    return $this->prefix;

  }

  public function get_magnifications() {

    $dir_fd = opendir($this->base_dir);

    while (false !== ($file = readdir($dir_fd))) {                // extraction des paramètres de grossissement par le serveur

       //echo $file;

       if (preg_match('/(.*)_([0-9]+)_([0-9]+)_([0-9]+)\.jpg$/', $file, $reg)) {

         $prefix = $reg[1];

         if ($prefix == $this->prefix) {

           $zoom = (int)$reg[2];

           $posx = (int)$reg[3]+1;

           $posy = (int)$reg[4]+1;

           if (!isset($zoom_array[$zoom]['nx']) || $zoom_array[$zoom]['nx'] < $posx) $zoom_array[$zoom]['nx'] = $posx;

           if (!isset($zoom_array[$zoom]['ny']) || $zoom_array[$zoom]['ny'] < $posy) $zoom_array[$zoom]['ny'] = $posy;

         }

       }

    }

    $this->zooms = $zoom_array;

    return $this->zooms;

  }

  public function coordsToCap($lat, $lon, $alt) {

    $params = $this->get_params();

    if (!isset($params['latitude']) || !isset($params['longitude'])) return false;

    $rt = 6371;  // Rayon de la terre

    $alt1 = isset($params['altitude']) ? $params['altitude'] : $alt;

    $lat1 = $params['latitude']*M_PI/180;

    $lon1 = $params['longitude']*M_PI/180;

    $alt2 = $alt;

    $lat2 = $lat * M_PI/180;

    $lon2 = $lon * M_PI/180;

    $dLat = $lat2-$lat1;

    $dLon = $lon2-$lon1;

    $a = sin($dLat/2) * sin($dLat/2) + sin($dLon/2) * sin($dLon/2) * cos($lat1) * cos($lat2);  //

    $angle = 2 * atan2(sqrt($a), sqrt(1-$a));

    $d = $angle * $rt;                    // distance du point en Kms

    $y = sin($dLon)*cos($lat2);

    $x = cos($lat1)*sin($lat2) - sin($lat1)*cos($lat2)*cos($dLon);

    $cap = atan2($y, $x);                 // cap pour atteindre le point en radians

    $e = atan2(($alt2 - $alt1)/1000 - $d*$d/(2*$rt), $d);  // angle de l'élévation en radians

    //    printf("%s, %s, %s, %s\n",$lat1, $params['latitude'], $lat, $dLat);

    return array($d, $cap*180/M_PI, $e*180/M_PI);   // les résultats sont en degrés

  }

  public function get_url($cap=false, $ele=false) {

          $o = sprintf('panorama.php?dir=%s&panorama=%s',

                          PANORAMA_FOLDER, $this->get_name());

          if ($cap && $ele) {

                  $o .= sprintf("&to_cap=%.3f&to_ele=%.3f", $cap, $ele);

          }

          return $o;

  }

  public static function get($name) {

          /** Instantiate a site_point, given its name

           */

          $pano_dir = PANORAMA_PATH.'/'.$name;

          return new site_point($pano_dir);

  }

  public function to_geoJSON() {

          $prm = $this->get_params();

                $name = $this->get_name();

                $lat = floatval($prm['latitude']);

                $lon = floatval($prm['longitude']);

                //$alt = $prm['altitude'];

                //$title = $prm['titre'];

                return array("type" => "Feature",

                             "geometry" => array(

                                                 "type" => "Point",

                                                 "coordinates" => [$lon, $lat]

                                                 ),

                             "properties" => array("name" => $name,

                                                   "type" => 'pano_point',

                                                   "view_url"  => $this->get_url())

                             );

  }

  public static function get_all($only_with_params=false) {

          /**

           * @param $only_with_params : filters out the panoramas which are not parametrized

           */

          $panos = array_diff(scandir(PANORAMA_PATH), array('..', '.'));

          $pano_instances = array();

          foreach ($panos as $pano_name) {

                  $pano =  site_point::get($pano_name);

                  if (! $only_with_params || $pano->has_params() ) {

                          $pano_instances[] = $pano;

                  }

          }

          return $pano_instances;

  }

}