import os
import datetime
from xml.dom.minidom import parse, parseString
from dynastie.generators.generator import DynastieGenerator
from django.db import models

class Index(DynastieGenerator):

    cur_page = 0
    nb_pages = 0
    cur_article = 0
    articles_per_page = 0
    filename = 'index'

    def createNavigation(self, articles, dom, root, node):
        if self.nb_pages == 0 or self.nb_pages == 1:
            return ''
        
        nav = ''
        if self.cur_page != 0:
            nav = nav + '<a href="/' + self.filename + '.html">&lt;&lt;</a>  '
            if self.cur_page == 1:
                nav = nav + '<a href="/' + self.filename + '.html">&lt;</a> '
            else:
                nav = nav + '<a href="/' + self.filename + str(self.cur_page) + '.html">&lt;</a> '

        start  = (self.cur_page/5)*5
        end = start + 10
        
        if end > self.nb_pages+1:
            end = self.nb_pages+1

        for i in range(start, end):
            if i == self.cur_page:
                nav = nav + str(i+1) + ' '
            else:
                if i == 0:
                    nav = nav + '<a href="/' + self.filename + '.html">1</a> '
                else:
                    nav = nav + '<a href="/' + self.filename + str(i) + '.html">' + str(i+1) + '</a> '

        if self.cur_page != self.nb_pages:
            nav = nav + '<a href="/' + self.filename + str(self.cur_page+1) + '.html">&gt;</a>  '
            nav = nav + '<a href="/' + self.filename + str(self.nb_pages) + '.html">&gt;&gt;</a>'

        new_dom = parseString('<div class="navigation">' + nav + '</div>')
        new_node = new_dom.getElementsByTagName('div')[0]
        root.replaceChild(new_node.cloneNode(True), node)

    def createArticle(self, article, dom, article_elem, root):
        values = {}
        values['title'] = article.title
        values['author'] = article.author.first_name
        values['date'] = article.creation_date.strftime("%d/%m/%Y")
        values['content'] = ''

        self.simpleTransform(values, dom, article_elem, root)

    def createArticles(self, articles, dom, root, node):
        articles_elem = self.createElement(dom, 'articles')
        for i in range(0, self.articles_per_page):
            article_elem = self.createElement(dom, 'article')
            if len(articles) > self.cur_article:
                self.createArticle(articles[self.cur_article], dom, article_elem, node)
            else:
                article_elem = self.createElement(dom, '', '<b>No articles yet</b>')
            articles_elem.appendChild(article_elem)

            self.cur_article = self.cur_article + 1
            if self.cur_article == len(articles):
                break
        root.replaceChild(articles_elem, node)

    def generate(self, blog, src, output):
        from dynastie.models import Article, Blog

        hooks = {'articles' : self.createArticles,
                 'navigation' : self.createNavigation}

        if not os.path.exists(src + '/_index.html'):
            self.addError('No _index.html found, exiting')
            return self.report

        try:
            dom = parse(src + '/_index.html')
        except xml.dom.DOMException as e:
            self.addError('Error parsing _index.html : ' + e)
            return self.report
            
        article_nodes = dom.getElementsByTagNameNS(self.URI, "articles")

        if not article_nodes is None:
            self.articles_per_page = int(article_nodes[0].getAttribute("limit"))
        else:
            self.addError('No tag dyn:articles found')

        now = datetime.datetime.now()
        cur_year = now.year
        articles = Article.objects.filter(creation_date__year=cur_year)

        if articles.count() < self.articles_per_page:
            articles = Article.objects.all()[:self.articles_per_page]

        if articles.count() > self.articles_per_page:
            self.nb_pages = articles.count() / self.articles_per_page

        filename = 'index.html'
        while self.cur_page <= self.nb_pages:
            #print 'Generate ' + filename
            nodes = dom.getElementsByTagName("*")
            self.parse(hooks, articles, dom, nodes[0])
            self.writeIfNotTheSame(output + '/' + filename, nodes[0].toxml('utf8'))
            self.cur_page = self.cur_page + 1
            filename = 'index' + str(self.cur_page) + '.html'
            dom = parse(src + '/_index.html')

        filename = output + '/' + filename

        while os.path.exists(filename):
            self.addReport('Removing unused ' + filename)
            os.unlink(filename)
            filename = filename + '.gz'
            if os.path.exists(filename):
                self.addReport('Removing unused ' + filename)
                os.unlink(filename)
            self.cur_page = self.cur_page + 1
            filename = output + '/index' + str(self.cur_page) + '.html'

        if not self.somethingWrote:
            self.addReport('Nothing changed')

        return self.report