/*
v02/12/2010
YQL Geo library by Christian Heilmann
Homepage: http://isithackday.com/geo/yql-geo-library
Copyright (c)2010 Christian Heilmann
Code licensed under the BSD License:
http://wait-till-i.com/license.txt
*/
var yqlgeo = function () {
    var callback;
    function get() {
        var args = arguments;
        for (var i = 0; i < args.length; i++) {
            if (typeof args[i] === 'function') {
                callback = args[i];
            }
        }
        if (args[0] === 'visitor') { getVisitor(); }
        if (typeof args[0] === 'string' && args[0] != 'visitor') {
            if (args[0]) {
                if (/^http:\/\/.*/.test(args[0])) {
                    getFromURL(args[0]);
                } else if (/^[\d+\.?]+$/.test(args[0])) {
                    getFromIP(args[0]);
                } else {
                    getFromText(args[0]);
                }
            }
        }
        var lat = args[0];
        var lon = args[1];
        if (typeof lat.join !== undefined && args[0][1]) {
            lat = args[0][0];
            lon = args[0][1];
        };
        if (isFinite(lat) && isFinite(lon)) {
            if (lat > -90 && lat < 90 &&
         lon > -180 && lon < 180) {
                getFromLatLon(lat, lon);
            }
        }
    }
    function getVisitor() {
        if (navigator.geolocation) {
            navigator.geolocation.getCurrentPosition(
        function (position) {
            getFromLatLon(position.coords.latitude,
                        position.coords.longitude);
        },
        function (error) {
            retrieveip();
        }
      );
        } else {
            retrieveip();
        }
    };

    function getFromIP(ip) {
        var yql = 'select * from geo.places where woeid in (' +
              'select place.woeid from flickr.places where (lat,lon) in(' +
              'select latitude,longitude from pidgets.geoip' +
              ' where ip="' + ip + '"))';
        load(yql, 'yqlgeo.retrieved');
    };

    function retrieveip() {
        jsonp('http://jsonip.appspot.com/?callback=yqlgeo.ipin');
    };

    function ipin(o) {
        getFromIP(o.ip);
    };

    function getFromLatLon(lat, lon) {
        var yql = 'select * from geo.places where woeid in (' +
              'select place.woeid from flickr.places where lat=' +
              lat + ' and  lon=' + lon + ')';
        load(yql, 'yqlgeo.retrieved');
    };

    function getFromURL(url) {
        var yql = 'select * from geo.places where woeid in (' +
              'select match.place.woeId from geo.placemaker where ' +
              'documentURL="' + url + '" and ' +
              'documentType="text/html" and appid="")';
        load(yql, 'yqlgeo.retrieved');
    }

    function getFromText(text) {
        var yql = 'select * from geo.places where woeid in (' +
              'select match.place.woeId from geo.placemaker where' +
              ' documentContent = "' + text + '" and ' +
              'documentType="text/plain" and appid = "")';
        load(yql, 'yqlgeo.retrieved');
    };

    function jsonp(src) {
        if (document.getElementById('yqlgeodata')) {
            var old = document.getElementById('yqlgeodata');
            old.parentNode.removeChild(old);
        }
        var head = document.getElementsByTagName('head')[0];
        var s = document.createElement('script');
        s.setAttribute('id', 'yqlgeodata');
        s.setAttribute('src', src);
        head.appendChild(s);
    };

    function load(yql, cb) {
        if (document.getElementById('yqlgeodata')) {
            var old = document.getElementById('yqlgeodata');
            old.parentNode.removeChild(old);
        }
        var src = 'http://query.yahooapis.com/v1/public/yql?q=' +
              encodeURIComponent(yql) + '&format=json&callback=' + cb + '&' +
              'env=store%3A%2F%2Fdatatables.org%2Falltableswithkeys';
        var head = document.getElementsByTagName('head')[0];
        var s = document.createElement('script');
        s.setAttribute('id', 'yqlgeodata');
        s.setAttribute('src', src);
        head.appendChild(s);
    };

    function retrieved(o) {
        if (o.query.results !== null) {
            callback(o.query.results);
        } else {
            callback({ error: o.query });
        }
    };
    return {
        get: get,
        retrieved: retrieved,
        ipin: ipin
    };
} ();