import hashlib
import string
from django.core import serializers
from django.core.urlresolvers import reverse
from django.http import HttpResponseRedirect
from django.http.response import HttpResponse
from django.template import RequestContext
from django.shortcuts import render, redirect, get_object_or_404
from django.utils import timezone

from boards import forms
import boards
from boards import utils
from boards.forms import ThreadForm, PostForm, SettingsForm, PlainErrorList, \
    ThreadCaptchaForm, PostCaptchaForm, LoginForm, ModeratorSettingsForm

from boards.models import Post, Tag, Ban, User, RANK_USER, SETTING_MODERATE
from boards import authors
from boards.utils import get_client_ip
import neboard


def index(request, page=0):
    context = _init_default_context(request)

    if utils.need_include_captcha(request):
        threadFormClass = ThreadCaptchaForm
        kwargs = {'request': request}
    else:
        threadFormClass = ThreadForm
        kwargs = {}

    if request.method == 'POST':
        form = threadFormClass(request.POST, request.FILES,
                               error_class=PlainErrorList, **kwargs)
        form.session = request.session

        if form.is_valid():
            return _new_post(request, form)
        if form.need_to_ban:
            # Ban user because he is suspected to be a bot
            _ban_current_user(request)
    else:
        form = threadFormClass(error_class=PlainErrorList, **kwargs)

    threads = []
    for thread in Post.objects.get_threads(page=int(page)):
        threads.append({'thread': thread,
                        'bumpable': thread.can_bump()})

    context['threads'] = None if len(threads) == 0 else threads
    context['form'] = form
    context['pages'] = range(Post.objects.get_thread_page_count())

    return render(request, 'boards/posting_general.html',
                  context)


def _new_post(request, form, thread_id=boards.models.NO_PARENT):
    """Add a new post (in thread or as a reply)."""

    ip = get_client_ip(request)
    is_banned = Ban.objects.filter(ip=ip).exists()

    if is_banned:
        return redirect(you_are_banned)

    data = form.cleaned_data

    title = data['title']
    text = data['text']

    if 'image' in data.keys():
        image = data['image']
    else:
        image = None

    tags = []

    new_thread = thread_id == boards.models.NO_PARENT
    if new_thread:
        tag_strings = data['tags']

        if tag_strings:
            tag_strings = tag_strings.split(' ')
            for tag_name in tag_strings:
                tag_name = string.lower(tag_name.strip())
                if len(tag_name) > 0:
                    tag, created = Tag.objects.get_or_create(name=tag_name)
                    tags.append(tag)

		    linked_tags = tag.get_linked_tags()
                    if len(linked_tags) > 0:
                        tags.extend(linked_tags)

    op = None if thread_id == boards.models.NO_PARENT else \
        get_object_or_404(Post, id=thread_id)
    post = Post.objects.create_post(title=title, text=text, ip=ip,
                                    thread=op, image=image,
                                    tags=tags, user=_get_user(request))

    thread_to_show = (post.id if new_thread else thread_id)

    if new_thread:
        return redirect(thread, post_id=thread_to_show)
    else:
        return redirect(reverse(thread, kwargs={'post_id': thread_to_show}) +
                        '#' + str(post.id))


def tag(request, tag_name, page=0):
    """
    Get all tag threads. Threads are split in pages, so some page is
    requested. Default page is 0.
    """

    tag = get_object_or_404(Tag, name=tag_name)
    threads = []
    for thread in Post.objects.get_threads(tag=tag, page=int(page)):
        threads.append({'thread': thread,
                        'bumpable': thread.can_bump()})

    if request.method == 'POST':
        form = ThreadForm(request.POST, request.FILES,
                          error_class=PlainErrorList)
        form.session = request.session

        if form.is_valid():
            return _new_post(request, form)
        if form.need_to_ban:
            # Ban user because he is suspected to be a bot
            _ban_current_user(request)
    else:
        form = forms.ThreadForm(initial={'tags': tag_name},
                                error_class=PlainErrorList)

    context = _init_default_context(request)
    context['threads'] = None if len(threads) == 0 else threads
    context['tag'] = tag
    context['pages'] = range(Post.objects.get_thread_page_count(tag=tag))

    context['form'] = form

    return render(request, 'boards/posting_general.html',
                  context)


def thread(request, post_id):
    """Get all thread posts"""

    if utils.need_include_captcha(request):
        postFormClass = PostCaptchaForm
        kwargs = {'request': request}
    else:
        postFormClass = PostForm
        kwargs = {}

    if request.method == 'POST':
        form = postFormClass(request.POST, request.FILES,
                             error_class=PlainErrorList, **kwargs)
        form.session = request.session

        if form.is_valid():
            return _new_post(request, form, post_id)
        if form.need_to_ban:
            # Ban user because he is suspected to be a bot
            _ban_current_user(request)
    else:
        form = postFormClass(error_class=PlainErrorList, **kwargs)

    posts = Post.objects.get_thread(post_id)

    context = _init_default_context(request)

    context['posts'] = posts
    context['form'] = form
    context['bumpable'] = posts[0].can_bump()
    if context['bumpable']:
        context['posts_left'] = neboard.settings.MAX_POSTS_PER_THREAD - len(
            posts)
        context['bumplimit_progress'] = str(float(context['posts_left']) /
		neboard.settings.MAX_POSTS_PER_THREAD * 100)

    return render(request, 'boards/thread.html', context)


def login(request):
    """Log in with user id"""

    context = _init_default_context(request)

    if request.method == 'POST':
        form = LoginForm(request.POST, request.FILES,
                         error_class=PlainErrorList)
        form.session = request.session

        if form.is_valid():
            user = User.objects.get(user_id=form.cleaned_data['user_id'])
            request.session['user_id'] = user.id
            return redirect(index)

    else:
        form = LoginForm()

    context['form'] = form

    return render(request, 'boards/login.html', context)


def settings(request):
    """User's settings"""

    context = _init_default_context(request)
    user = _get_user(request)
    is_moderator = user.is_moderator()

    if request.method == 'POST':
        if is_moderator:
            form = ModeratorSettingsForm(request.POST,
                                          error_class=PlainErrorList)
        else:
            form = SettingsForm(request.POST, error_class=PlainErrorList)

        if form.is_valid():
            selected_theme = form.cleaned_data['theme']

            user.save_setting('theme', selected_theme)

            if is_moderator:
                moderate = form.cleaned_data['moderate']
                user.save_setting(SETTING_MODERATE, moderate)

            return redirect(settings)
    else:
        selected_theme = _get_theme(request)

        if is_moderator:
            form = ModeratorSettingsForm(initial={'theme': selected_theme,
                                         'moderate': context['moderator']},
                                error_class=PlainErrorList)
        else:
            form = SettingsForm(initial={'theme': selected_theme},
                                error_class=PlainErrorList)

    context['form'] = form

    return render(request, 'boards/settings.html', context)


def all_tags(request):
    """All tags list"""

    context = _init_default_context(request)
    context['all_tags'] = Tag.objects.get_not_empty_tags()

    return render(request, 'boards/tags.html', context)


def jump_to_post(request, post_id):
    """Determine thread in which the requested post is and open it's page"""

    post = get_object_or_404(Post, id=post_id)

    if not post.thread:
        return redirect(thread, post_id=post.id)
    else:
        return redirect(reverse(thread, kwargs={'post_id': post.thread.id})
                        + '#' + str(post.id))


def authors(request):
    """Show authors list"""

    context = _init_default_context(request)
    context['authors'] = boards.authors.authors

    return render(request, 'boards/authors.html', context)


def delete(request, post_id):
    """Delete post"""

    user = _get_user(request)
    post = get_object_or_404(Post, id=post_id)

    if user.is_moderator():
        # TODO Show confirmation page before deletion
        Post.objects.delete_post(post)
    
    if not post.thread:
        return _redirect_to_next(request)
    else:
        return redirect(thread, post_id=post.thread.id)


def ban(request, post_id):
    """Ban user"""

    user = _get_user(request)
    post = get_object_or_404(Post, id=post_id)

    if user.is_moderator():
        # TODO Show confirmation page before ban
        Ban.objects.get_or_create(ip=post.poster_ip)

    return _redirect_to_next(request)


def you_are_banned(request):
    """Show the page that notifies that user is banned"""

    context = _init_default_context(request)
    return render(request, 'boards/staticpages/banned.html', context)


def page_404(request):
    """Show page 404 (not found error)"""

    context = _init_default_context(request)
    return render(request, 'boards/404.html', context)


def tag_subscribe(request, tag_name):
    """Add tag to favorites"""

    user = _get_user(request)
    tag = get_object_or_404(Tag, name=tag_name)

    if not tag in user.fav_tags.all():
        user.fav_tags.add(tag)

    return _redirect_to_next(request)


def tag_unsubscribe(request, tag_name):
    """Remove tag from favorites"""

    user = _get_user(request)
    tag = get_object_or_404(Tag, name=tag_name)

    if tag in user.fav_tags.all():
        user.fav_tags.remove(tag)

    return _redirect_to_next(request)


def static_page(request, name):
    """Show a static page that needs only tags list and a CSS"""

    context = _init_default_context(request)
    return render(request, 'boards/staticpages/' + name + '.html', context)


def api_get_post(request, post_id):
    """
    Get the JSON of a post. This can be
    used as and API for external clients.
    """

    post = get_object_or_404(Post, id=post_id)

    json = serializers.serialize("json", [post], fields=(
        "pub_time", "_text_rendered", "title", "text", "image",
        "image_width", "image_height", "replies", "tags"
    ))

    return HttpResponse(content=json)


def get_post(request, post_id):
    """Get the html of a post. Used for popups."""

    post = get_object_or_404(Post, id=post_id)

    context = RequestContext(request)
    context["post"] = post

    return render(request, 'boards/post.html', context)


def _get_theme(request, user=None):
    """Get user's CSS theme"""

    if not user:
        user = _get_user(request)
    theme = user.get_setting('theme')
    if not theme:
        theme = neboard.settings.DEFAULT_THEME

    return theme


def _init_default_context(request):
    """Create context with default values that are used in most views"""

    context = RequestContext(request)

    user = _get_user(request)
    context['user'] = user
    context['tags'] = user.get_sorted_fav_tags()

    theme = _get_theme(request, user)
    context['theme'] = theme
    context['theme_css'] = 'css/' + theme + '/base_page.css'

    # This shows the moderator panel
    moderate = user.get_setting(SETTING_MODERATE)
    if moderate == 'True':
        context['moderator'] = user.is_moderator()
    else:
        context['moderator'] = False

    return context


def _get_user(request):
    """
    Get current user from the session. If the user does not exist, create
    a new one.
    """

    session = request.session
    if not 'user_id' in session:
        request.session.save()

        md5 = hashlib.md5()
        md5.update(session.session_key)
        new_id = md5.hexdigest()

        time_now = timezone.now()
        user = User.objects.create(user_id=new_id, rank=RANK_USER,
                                   registration_time=time_now)

        session['user_id'] = user.id
    else:
        user = User.objects.get(id=session['user_id'])

    return user


def _redirect_to_next(request):
    """
    If a 'next' parameter was specified, redirect to the next page. This is
    used when the user is required to return to some page after the current
    view has finished its work.
    """

    if 'next' in request.GET:
        next_page = request.GET['next']
        return HttpResponseRedirect(next_page)
    else:
        return redirect(index)


def _ban_current_user(request):
    """Add current user to the IP ban list"""

    ip = utils.get_client_ip(request)
    Ban.objects.get_or_create(ip=ip)