#!/usr/bin/env  python2
__license__   = 'GPL v3'

from calibre.web.feeds.news import BasicNewsRecipe

def absurl(url):
    if url.startswith('/'):
        url = 'http://www.scientificamerican.com' + url
    return url

class ScientificAmerican(BasicNewsRecipe):
    title                 = u'Scientific American'
    description           = u'Popular Science. Monthly magazine.'
    category              = 'science'
    __author__            = 'Kovid Goyal'
    no_stylesheets        = True
    language              = 'en'
    publisher             = 'Nature Publishing Group'
    remove_empty_feeds    = True
    remove_javascript     = True

    needs_subscription    = 'optional'

    keep_only_tags = [
        dict(attrs={'class':['article-title', 'article-dek', 'article-author article-date', 'article-content', 'article-slatwallPayWall']}),
    ]

    def get_browser(self, *args):
        br = BasicNewsRecipe.get_browser(self)
        if self.username and self.password:
            br.open('https://www.scientificamerican.com/my-account/login/')
            br.select_form(predicate=lambda f:f.attrs.get('id') == 'login')
            br['emailAddress'] = self.username
            br['password'] = self.password
            br.submit()
        return br

    def parse_index(self):
        # Get the cover, date and issue URL
        root = self.index_to_soup('http://www.scientificamerican.com/sciammag/', as_tree=True)
        for a in root.xpath('''descendant-or-self::*[@class and contains(concat(' ', normalize-space(@class), ' '), ' archiveIssues ')]/descendant-or-self::*/a[@class and contains(concat(' ', normalize-space(@class), ' '), ' cover ') and (@href)]'''):
            self.cover_url = absurl(a.xpath('descendant-or-self::img[@src]')[0].get('src'))
            root = self.index_to_soup(absurl(a.get('href')), as_tree=True)
            for a in a.xpath('following-sibling::a[@href]'):
                self.timefmt = self.tag_to_string(a).strip()
                break
            break
        else:
            raise ValueError('The Scientific American website has changed, this recipe needs to be updated')

        # Now parse the actual issue to get the list of articles
        feeds = []
        for i, div in enumerate(root.xpath('''descendant-or-self::div[@class and contains(concat(' ', normalize-space(@class), ' '), ' toc-features ')] | descendant-or-self::div[@class and contains(concat(' ', normalize-space(@class), ' '), ' toc-departments ')]''')):
            if i == 0:
                feeds.append(('Features', list(self.parse_sciam_features(div))))
            else:
                feeds.extend(self.parse_sciam_departments(div))

        return feeds

    def parse_sciam_features(self, div):
        for h4 in div.xpath('''descendant-or-self::li/descendant-or-self::*/a[@href]/descendant-or-self::*/h4'''):
            title = self.tag_to_string(h4)
            a = h4.getparent()
            url = absurl(a.get('href'))
            desc = ''
            for span in a.xpath('following-sibling::span'):
                desc = self.tag_to_string(span)
                break
            self.log('Found feature article: %s at %s' % (title, url))
            self.log('\t' + desc)
            yield {'title':title, 'url':url, 'description':desc}

    def parse_sciam_departments(self, div):
        section_title, articles = 'Unknown', []
        for x in div.xpath('''descendant-or-self::li/descendant-or-self::*/a[@href]/descendant-or-self::*/h3 | descendant-or-self::li/descendant-or-self::*/span[@class and contains(concat(' ', normalize-space(@class), ' '), ' deptTitle ')]/descendant-or-self::*/a[@href]'''):
            if x.tag == 'a':
                if articles:
                    yield section_title, list(articles)
                section_title = self.tag_to_string(x)
                del articles[:]
                self.log('\nFound section: %s' % section_title)
            else:
                title = self.tag_to_string(x)
                a = x.getparent()
                url = absurl(a.get('href'))
                articles.append({'title':title, 'url':url, 'description':''})
                self.log('\tFound article: %s at %s' % (title, url))