import urllib
import urlparse 
 
def get_favicon_url(url, retry=3, try_home_page=True):
    """ Try to find a favicon url on the given page """
 
    parsed_url = urlparse.urlparse(url)
    url_root = "%s://%s" % (parsed_url.scheme, parsed_url.netloc)
 
    try:
        # try to get it using a regex on the current URL
        html = fetch_url(url, retry=retry)
        html = html.decode('ascii', errors='ignore')
        pattern = r"""
                               href=(?:"|')\s*
                               (?P<favicon>[^\s'"]*favicon.[a-zA-Z]{3,4})
                               \s*(?:"|')
                          """
 
        match = re.search(pattern, html, re.U|re.VERBOSE)
        favicon_url = match.groups()[0]
 
    except IOError:
        # this is a network error so eventually, let it crash
        if not try_home_page:
            raise
        # try with the home page, maybe this one is accessible
        favicon_url = get_favicon_url(url_root, retry=retry,
                                                       try_home_page=False)
    except (IndexError, AttributeError):
        # url is not on this page, try the home page
        if try_home_page:
            return get_favicon_url(url_root, retry=retry, try_home_page=False)
 
        # can't find the favicon url, default to standard url
        favicon_url = '/favicon.ico'
 
    # make sure to have the domain of the original website in the favicon url
    if url_root not in favicon_url:
        favicon_url = "%s/%s" % (url_root, favicon_url.lstrip('/'))
 
    return favicon_url
 
 
def fetch_favicon(url, retry=3):
    """ Returns the bytes of the favicon of this site """
    favicon_url = get_favicon_url(url, retry=retry)
    return fetch_url(favicon_url, retry=retry)

 
import base64
from bottle import post, HTTPError
 
@post('/favicon')
def fetch_favicon_base64():
    """ Return the favicon URL from a website """
    try:
        url = request.POST['url']
    except KeyError:
        raise HTTPError(400, "You must pass a site URL")
    try:
        # return favicon as base64 url to be easily included in
        # a img tag
        favicon = fetch_favicon(url)
        return b'data:image/x-icon;base64,' + base64.b64encode(favicon)
    except (IOError):
        raise HTTPError(400, "Unable to find any favicon URL")

 $.post('/favicon', {url: url}).done(function(data){
 
        // load an image with the base64 data of the favicon
        var image = new Image;
        image.src = data;
        image.onload = function() {
 
            // ask ColorThief for the main favicon colors
            var colorThief = new ColorThief();
            var bc = colorThief.getPalette(image);
 
            // some tools to convert the RGB array into
            // rgb hex string
            function componentToHex(c) {
                var hex = c.toString(16);
                return hex.length == 1 ? "0" + hex : hex;
            }
 
            function rgbToHex(array) {
                return componentToHex(array[0]) + componentToHex(array[1]) + componentToHex(array[2]);
            }
 
            // make the color brigther
            function increase_brightness(hex, percent){
 
                // convert 3 char codes --> 6, e.g. `E0F` --> `EE00FF`
                if(hex.length == 3){
                    hex = hex.replace(/(.)/g, '$1$1');
                }
 
                var r = parseInt(hex.substr(0, 2), 16),
                    g = parseInt(hex.substr(2, 2), 16),
                    b = parseInt(hex.substr(4, 2), 16);
 
                return '' +
                   ((0|(1<<8) + r + (256 - r) * percent / 100).toString(16)).substr(1) +
                   ((0|(1<<8) + g + (256 - g) * percent / 100).toString(16)).substr(1) +
                   ((0|(1<<8) + b + (256 - b) * percent / 100).toString(16)).substr(1);
            }
 
            /* Define board colors */
            var header =  '#' + rgbToHex(bc[0]);
            var odd = '#' + increase_brightness(rgbToHex(bc[1]), 90);
            var even = '#' + increase_brightness(rgbToHex(bc[2]), 90);
 
});