var WebKitDetect = {  };

WebKitDetect.isWebKit = function isWebKit()
{
    return RegExp(" AppleWebKit/").test(navigator.userAgent);
}

// If the user agent is WebKit, returns an array of numbers matching the "." separated 
// fields in the WebKit version number, with an "isNightlyBuild" property specifying
// whether the user agent is a WebKit nightly build. Otherwise, returns null.
//
// Example: 418.10.1 => [ 418, 10, 1 ] isNightlyBuild: false
WebKitDetect.version = function version() 
{
    /* Some example strings: 
            Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en) AppleWebKit/418.9.1 (KHTML, like Gecko) Safari/419.3
            Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en) AppleWebKit/420+ (KHTML, like Gecko) Safari/521.32
     */
     
    // grab (AppleWebKit/)(xxx.x.x)
    var webKitFields = RegExp("( AppleWebKit/)([^ ]+)").exec(navigator.userAgent);
    if (!webKitFields || webKitFields.length < 3)
        return null;
    var versionString = webKitFields[2];

    var isNightlyBuild = versionString.indexOf("+") != -1;

    // Remove '+' or any other stray characters
    var invalidCharacter = RegExp("[^\\.0-9]").exec(versionString);
    if (invalidCharacter)
        versionString = versionString.slice(0, invalidCharacter.index);
    
    var version = versionString.split(".");
    version.isNightlyBuild = isNightlyBuild;
    return version;
}

// If the user agent is a WebKit version greater than or equal to the version specified
// in the string minimumString, returns true. Returns false otherwise. minimumString 
// defaults to "".
//
// Example usage: WebKitDetect.versionIsAtLeast("418.10.1")
WebKitDetect.versionIsAtLeast = function versionIsAtLeast(minimumString)
{
    function toIntOrZero(s) 
    {
        var toInt = parseInt(s);
        return isNaN(toInt) ? 0 : toInt;
    }

    if (minimumString === undefined)
        minimumString = "";
    
    var minimum = minimumString.split(".");
    var version = WebKitDetect.version();

    if (!version)
        return false;
        
    if (version.isNightlyBuild)
        return true;

    for (var i = 0; i < minimum.length; i++) {
        var versionField = toIntOrZero(version[i]);
        var minimumField = toIntOrZero(minimum[i]);
        
        if (versionField > minimumField)
            return true;
        if (versionField < minimumField)
            return false;
    }

    return true;
}

WebKitDetect.isMobile = function isMobile()
{
    return WebKitDetect.isWebKit() && RegExp(" Mobile/").test(navigator.userAgent);
}

WebKitDetect.mobileDevice = function mobileDevice()
{
    if (!WebKitDetect.isMobile())
        return null;
        
    var fields = RegExp("(Mozilla/5.0 \\()([^;]+)").exec(navigator.userAgent);
    if (!fields || fields.length < 3)
        return null;
    return fields[2];
}

// Example: 1C28 => [ 1, C, 28 ]
WebKitDetect._mobileVersion = function _mobileVersion(versionString)
{
    var fields = RegExp("([0-9]+)([A-Z]+)([0-9]+)").exec(versionString);
    if (!fields || fields.length != 4)
        return null;
    return [ fields[1], fields[2], fields[3] ];
}

WebKitDetect.mobileVersion = function mobileVersion()
{
    // grab (Mobile/)(nxnnn)
    var fields = RegExp("( Mobile/)([^ ]+)").exec(navigator.userAgent);
    if (!fields || fields.length < 3)
        return null;
    var versionString = fields[2];
    
    return WebKitDetect._mobileVersion(versionString);
}

WebKitDetect.mobileVersionIsAtLeast = function mobileVersionIsAtLeast(minimumString)
{
    function toIntOrZero(s) 
    {
        var toInt = parseInt(s);
        return isNaN(toInt) ? 0 : toInt;
    }

    if (minimumString === undefined)
        minimumString = "";

    var minimum = WebKitDetect._mobileVersion(minimumString);
    var version = WebKitDetect.mobileVersion();

    if (!version)
        return false;
        
    var majorVersInt = toIntOrZero(version[0]);
    var majorMinInt = toIntOrZero(minimum[0]);
    if (majorVersInt > majorMinInt)
        return true;
    if (majorVersInt < majorMinInt)
        return false;
    
    var majorVersAlpha = version[1];
    var majorMinAlpha = minimum[1];
    if (majorVersAlpha > majorMinAlpha)
        return true;
    if (majorVersAlpha < majorMinAlpha)
        return false;
    
    var minorVersInt = toIntOrZero(version[2]);
    var minorMinInt = toIntOrZero(minimum[2]);
    if (minorVersInt > minorMinInt)
        return true;
    if (minorVersInt < minorMinInt)
        return false;
    
    return true;
}

if (WebKitDetect.isWebKit() && WebKitDetect.isMobile()) {
  var answer_is_yes = confirm("iPhone用ページに移動しますか？");
  if (answer_is_yes) {
    location.href = "http://www.scvb.or.jp/iphone/";
    }
};