from django.shortcuts import render, redirect
from django.http import HttpResponse
from django.contrib.auth.models import User
from django.contrib.auth.decorators import login_required
from django.core.paginator import Paginator
from django.db.models import Q
import markdown

from .models import ArticlePost
from .form import ArticlePostForm
from comment.models import CommentPost


# 视图函数
def article_list(request):
    search = request.GET.get('search')
    order = request.GET.get('order')
    if search:
        if order == 'total_views':
            article_list = ArticlePost.objects.filter(
                Q(title__icontains=search) |
                Q(body__icontains=search)
            ).order_by('-total_views')
        else:
            article_list = ArticlePost.objects.filter(
                Q(title__icontains=search) |
                Q(body__icontains=search)
            )
    else:
        search = ''
        if order == 'total_views':
            article_list = ArticlePost.objects.all().order_by('total_views')
        else:
            article_list = ArticlePost.objects.all()
    paginator = Paginator(article_list, 3)
    page = request.GET.get('page')
    articles = paginator.get_page(page)
    context = {'articles': articles, 'order': order, 'search': search}
    return render(request, 'article/list.html', context)


def article_detail(request, id):
    articles = ArticlePost.objects.get(id=id)
    comments = CommentPost.objects.filter(article=id)
    articles.total_views += 1
    articles.save(update_fields=['total_views'])
    md = markdown.Markdown(
        extensions=[
            'markdown.extensions.extra',
            'markdown.extensions.codehilite',
            'markdown.extensions.toc'
        ])
    articles.body = md.convert(articles.body)
    context = {'article': articles, 'toc': md.toc, 'comments': comments}
    return render(request, 'article/detail.html', context)


@login_required(login_url='/user/login/')
def article_create(request):
    if request.method == 'POST':
        article_post_form = ArticlePostForm(data=request.POST)
        # 判断提交的数据是否满足模型要求
        if article_post_form.is_valid():
            # 保存数据，但是暂时不提交到数据库中
            new_article = article_post_form.save(commit=False)
            new_article.author = User.objects.get(id=request.user.id)
            # 将新文章保存到数据库中
            new_article.save()
            return redirect("article:article_list")
        # 如果数据不合法，返回错误信息
        else:
            return HttpResponse("表单有错误，请重新填写")
    # 如果用户请求获取数据
    else:
        # 创建表单类实例
        article_post_form = ArticlePostForm()
        context = {'article_post_form': article_post_form}
        # 返回模板
        return render(request, 'article/create.html', context)


def article_delete(request, id):
    article = ArticlePost.objects.get(id=id)
    article.delete()
    return redirect("article:article_list")


@login_required(login_url='/user/login/')
def article_safe_delete(request, id):
    if request.method == 'POST':
        article = ArticlePost.objects.get(id=id)
        if article.author == User.objects.get(id=request.user.id):
            article.delete()
            return redirect("article:article_list")
        else:
            return HttpResponse("你无权限进行此操作")
    else:
        return HttpResponse("仅允许POST请求")


@login_required(login_url='/user/login/')
def article_update(request, id):
    article = ArticlePost.objects.get(id=id)
    if article.author == User.objects.get(id=request.user.id):
        if request.method == 'POST':
            article_post_form = ArticlePostForm(data=request.POST)
            if article_post_form.is_valid():
                article.title = request.POST['title']
                article.body = request.POST['body']
                article.save()
                return redirect("article:article_detail", id=id)
            else:
                return HttpResponse("表单内容有误，请重新填写")
        else:
            article_post_form = ArticlePostForm()
            context = {'article': article, 'article_post_form': article_post_form}
            return render(request, 'article/update.html', context)
    else:
        return HttpResponse("你无权进行此操作")