<?php
/* Copyright (c) 2009 Arnaud Renevier, Inc, published under the modified BSD
   license. */

// XXX: put that function somewhere else. It's used in changes.php
function relative_path ($url_str) {
    $url = parse_url ($url_str);
    if ($url ['host'] != $_SERVER ['HTTP_HOST']) {
        return null;
    }

    // first strip common directory names
    $url_path = split ('/', $url ['path']);
    $script_path = split ('/', $_SERVER ['SCRIPT_NAME']);
    $len = min (count ($url_path), count ($script_path));
    while ($url_path [0] == $script_path [0]) {
        array_shift ($url_path);
        array_shift ($script_path);
    }

    // $url_path contains $script_path; abort
    if (count ($script_path) == 0) { 
        return null;
    }

    // now, create relative path
    $relpath = "";
    for ($i = 0; $i < (count ($script_path) - 1); $i++) {
        $relpath .= "../";
    }
    $relpath .= join ("/", $url_path);
    return $relpath;
}

class feature {
    private $imgurl = null;
    private $title = null;
    private $description = null;
    private $lon = null;
    private $lat = null;

    const err_lonlat_invalid = 1;

    function __construct ($imgurl, $title, $description, $lon, $lat) {
        // imgurl
        // tries to transform full url in relative path
        $relpath = relative_path ($imgurl);
        if (isset ($relpath)) {
            $this->imgurl = $relpath;
        } else {
            $this->imgurl = $imgurl;
        }

        // title
        $this->title = $title;

        // description
        $this->description = $description;

        // longitude
        if (!isset ($lon) || !is_numeric ($lon) ||
             ($lon < -180) || ($lon > 180)) {
            throw new Exception ($this->err_lonlat_invalid);
        }
        $this->lon = $lon;

        // latitude
        if (!isset ($lat) || !is_numeric ($lat) ||
             ($lat < -90) || ($lat > 90)) {
            throw new Exception ($this->err_lonlat_invalid);
        }
        $this->lat = $lat;
    }

    public function __get ($attr) {
        if (isset ($this->$attr)) return $this->$attr;
            else throw new Exception ('Unknow attribute '.$attr);
    }

    public function __set ($attr,$value) {
        throw new Exception ('properties can only be set in constructor');
    }

    public function imgurl_exists () {
        if (file_exists ($this->imgurl)) {
            return true;
        }
        if (!function_exists ("curl_init")) {
            return false;
        }
        $handle   = curl_init ($this->imgurl);
        if ($handle === false)
        {
            return false;
        }
        curl_setopt ($handle, CURLOPT_NOBODY, true);
        curl_setopt ($handle, CURLOPT_CONNECTTIMEOUT, 10);
        curl_setopt ($handle, CURLOPT_TIMEOUT, 10);
        $connectable = curl_exec ($handle);
        curl_close ($handle);  
        return $connectable;
    }
}

interface anydbConnection {
    const err_driver_unavailable = 1;
    const err_connection = 2;
    const err_unknown_database = 3;
    const err_query = 3;

    /*
     * connect to database; That method may be called multiple times.
     */
    public function connect($host, $user, $pwd, $dbname, $dbprefix);

    /*
     * return true if users table already exists
     */
    public function users_table_exists();

    /*
     * create users table; if $error_if_exists is true; throws an err_query
     * error in case users table already exists.
     */
    public function create_users_table($error_if_exists);

    /*
     * return true if items table already exists
     */
    public function items_table_exists();

    /*
     * create items table; if $error_if_exists is true; throws an err_query
     * error in case items table already exists.
     */
    public function create_items_table($error_if_exists);

    /*
     * set password $pwd for user $usrname. If $usrname does not exist, create
     * it.
     */
    public function setpwd($usrname, $pwd);

    /*
     * check that $pwd_md5 is md5 for $username password.
     */
    public function checkpwdmd5($usrname, $pwd_md5);

    /*
     * saves feature in database. Returns false if $feature does not exist and
     * if $feature->imgurl is not accessible; returns true otherwise.
     */
    public function save_feature($feature);

    /*
     * delete feature from database. Returns true in case of success, even if
     * image was not referenced in the database.
     */
    public function delete_feature($feature);

    /*
     * Returns feature with given imgurl. If none exists, returns null.
     */
    public function getfeature($imgurl);

    /*
     * returns an array of available features
     */
    public function listfeatures();

    /*
     * returns true if a feature with imgurl exists
     */
    public function imgurl_exists($imgurl);

    /*
     * returns Minimum Bounding Rectangle containing all feature locations.
     * That function must return a result even if database is not functional.
     * Minimum Bounding Rectangle is presented as an Array:
     *      [bottom, left, top, right]
     */
    public function mbr();

    /*
     * get name of database backend
     */
    public function getdbname();
}
?>