text: from flask import render_template, redirect, url_for, abort, flash, request,\
      current_app, make_response
  from flask_login import login_required, current_user
  from flask_sqlalchemy import get_debug_queries
  from . import main
  from .forms import EditProfileForm, EditProfileAdminForm, PostForm,\
      CommentForm
  from .. import db
  from ..models import Permission, Role, User, Post, Comment
  from ..decorators import admin_required, permission_required
  
  
  @main.after_app_request
  def after_request(response):
      for query in get_debug_queries():
          if query.duration >= current_app.config['FLASKY_SLOW_DB_QUERY_TIME']:
              current_app.logger.warning(
                  'Slow query: %s\nParameters: %s\nDuration: %fs\nContext: %s\n'
                  % (query.statement, query.parameters, query.duration,
                     query.context))
      return response
  
  
  @main.route('/shutdown')
  def server_shutdown():
      if not current_app.testing:
          abort(404)
      shutdown = request.environ.get('werkzeug.server.shutdown')
      if not shutdown:
          abort(500)
      shutdown()
      return 'Shutting down...'
  
  
  @main.route('/', methods=['GET', 'POST'])
  @login_required
  def index():
      form = PostForm()
      if current_user.can(Permission.WRITE_ARTICLES) and \
              form.validate_on_submit():
          post = Post(body=form.body.data,
                      author=current_user._get_current_object())
          db.session.add(post)
          return redirect(url_for('.index'))
  
      page = request.args.get('page', 1, type=int)
      show_followed = False
      if current_user.is_authenticated:
          show_followed = bool(request.cookies.get('show_followed', ''))
      if show_followed:
          query = current_user.followed_posts
      else:
          query = Post.query
      pagination = query.order_by(Post.timestamp.desc()).paginate(
          page, per_page=current_app.config['FLASKY_POSTS_PER_PAGE'],
          error_out=False)
      posts = pagination.items
      return render_template('index.html', form=form, posts=posts,
                             show_followed=show_followed, pagination=pagination)
  
  
  @main.route('/user/<username>')
  def user(username):
      user = User.query.filter_by(username=username).first_or_404()
      page = request.args.get('page', 1, type=int)
      pagination = user.posts.order_by(Post.timestamp.desc()).paginate(
          page, per_page=current_app.config['FLASKY_POSTS_PER_PAGE'],
          error_out=False)
      posts = pagination.items
      return render_template('user.html', user=user, posts=posts,
                             pagination=pagination)
  
  
  @main.route('/edit-profile', methods=['GET', 'POST'])
  @login_required
  def edit_profile():
      form = EditProfileForm()
      if form.validate_on_submit():
          current_user.name = form.name.data
          current_user.location = form.location.data
          current_user.about_me = form.about_me.data
          db.session.add(current_user)
          flash('Your profile has been updated.')
          return redirect(url_for('.user', username=current_user.username))
      form.name.data = current_user.name
      form.location.data = current_user.location
      form.about_me.data = current_user.about_me
      return render_template('edit_profile.html', form=form)
  
  
  @main.route('/edit-profile/<int:id>', methods=['GET', 'POST'])
  @login_required
  @admin_required
  def edit_profile_admin(id):
      user = User.query.get_or_404(id)
      form = EditProfileAdminForm(user=user)
      if form.validate_on_submit():
          user.email = form.email.data
          user.username = form.username.data
          user.confirmed = form.confirmed.data
          user.role = Role.query.get(form.role.data)
          user.name = form.name.data
          user.location = form.location.data
          user.about_me = form.about_me.data
          db.session.add(user)
          flash('The profile has been updated.')
          return redirect(url_for('.user', username=user.username))
      form.email.data = user.email
      form.username.data = user.username
      form.confirmed.data = user.confirmed
      form.role.data = user.role_id
      form.name.data = user.name
      form.location.data = user.location
      form.about_me.data = user.about_me
      return render_template('edit_profile.html', form=form, user=user)
  
  
  @main.route('/post/<int:id>', methods=['GET', 'POST'])
  def post(id):
      post = Post.query.get_or_404(id)
      form = CommentForm()
      if form.validate_on_submit():
          comment = Comment(body=form.body.data,
                            post=post,
                            author=current_user._get_current_object())
          db.session.add(comment)
          flash('您的提交已经显示.')
          return redirect(url_for('.post', id=post.id, page=-1))
      page = request.args.get('page', 1, type=int)
      if page == -1:
          page = (post.comments.count() - 1) // \
              current_app.config['FLASKY_COMMENTS_PER_PAGE'] + 1
      pagination = post.comments.order_by(Comment.timestamp.asc()).paginate(
          page, per_page=current_app.config['FLASKY_COMMENTS_PER_PAGE'],
          error_out=False)
      comments = pagination.items
      return render_template('post.html', posts=[post], form=form,
                             comments=comments, pagination=pagination)
  
  
  @main.route('/edit/<int:id>', methods=['GET', 'POST'])
  @login_required
  def edit(id):
      post = Post.query.get_or_404(id)
      if current_user != post.author and \
              not current_user.can(Permission.ADMINISTER):
          abort(403)
      form = PostForm()
      if form.validate_on_submit():
          post.body = form.body.data
          db.session.add(post)
          flash('The post has been updated.')
          return redirect(url_for('.post', id=post.id))
      form.body.data = post.body
      return render_template('edit_post.html', form=form)
  
  
  @main.route('/follow/<username>')
  @login_required
  @permission_required(Permission.FOLLOW)
  def follow(username):
      user = User.query.filter_by(username=username).first()
      if user is None:
          flash('Invalid user.')
          return redirect(url_for('.index'))
      if current_user.is_following(user):
          flash('You are already following this user.')
          return redirect(url_for('.user', username=username))
      current_user.follow(user)
      flash('You are now following %s.' % username)
      return redirect(url_for('.user', username=username))
  
  
  @main.route('/unfollow/<username>')
  @login_required
  @permission_required(Permission.FOLLOW)
  def unfollow(username):
      user = User.query.filter_by(username=username).first()
      if user is None:
          flash('Invalid user.')
          return redirect(url_for('.index'))
      if not current_user.is_following(user):
          flash('You are not following this user.')
          return redirect(url_for('.user', username=username))
      current_user.unfollow(user)
      flash('You are not following %s anymore.' % username)
      return redirect(url_for('.user', username=username))
  
  
  @main.route('/followers/<username>')
  def followers(username):
      user = User.query.filter_by(username=username).first()
      if user is None:
          flash('Invalid user.')
          return redirect(url_for('.index'))
      page = request.args.get('page', 1, type=int)
      pagination = user.followers.paginate(
          page, per_page=current_app.config['FLASKY_FOLLOWERS_PER_PAGE'],
          error_out=False)
      follows = [{'user': item.follower, 'timestamp': item.timestamp}
                 for item in pagination.items]
      return render_template('followers.html', user=user, title="Followers of",
                             endpoint='.followers', pagination=pagination,
                             follows=follows)
  
  
  @main.route('/followed-by/<username>')
  def followed_by(username):
      user = User.query.filter_by(username=username).first()
      if user is None:
          flash('Invalid user.')
          return redirect(url_for('.index'))
      page = request.args.get('page', 1, type=int)
      pagination = user.followed.paginate(
          page, per_page=current_app.config['FLASKY_FOLLOWERS_PER_PAGE'],
          error_out=False)
      follows = [{'user': item.followed, 'timestamp': item.timestamp}
                 for item in pagination.items]
      return render_template('followers.html', user=user, title="Followed by",
                             endpoint='.followed_by', pagination=pagination,
                             follows=follows)
  
  
  @main.route('/all')
  @login_required
  def show_all():
      resp = make_response(redirect(url_for('.index')))
      resp.set_cookie('show_followed', '', max_age=30*24*60*60)
      return resp
  
  
  @main.route('/followed')
  @login_required
  def show_followed():
      resp = make_response(redirect(url_for('.index')))
      resp.set_cookie('show_followed', '1', max_age=30*24*60*60)
      return resp
  
  
  @main.route('/moderate')
  @login_required
  @permission_required(Permission.MODERATE_COMMENTS)
  def moderate():
      page = request.args.get('page', 1, type=int)
      pagination = Comment.query.order_by(Comment.timestamp.desc()).paginate(
          page, per_page=current_app.config['FLASKY_COMMENTS_PER_PAGE'],
          error_out=False)
      comments = pagination.items
      return render_template('moderate.html', comments=comments,
                             pagination=pagination, page=page)
  
  
  @main.route('/moderate/enable/<int:id>')
  @login_required
  @permission_required(Permission.MODERATE_COMMENTS)
  def moderate_enable(id):
      comment = Comment.query.get_or_404(id)
      comment.disabled = False
      db.session.add(comment)
      return redirect(url_for('.moderate',
                              page=request.args.get('page', 1, type=int)))
  
  
  @main.route('/moderate/disable/<int:id>')
  @login_required
  @permission_required(Permission.MODERATE_COMMENTS)
  def moderate_disable(id):
      comment = Comment.query.get_or_404(id)
      comment.disabled = True
      db.session.add(comment)
      return redirect(url_for('.moderate',
                              page=request.args.get('page', 1, type=int)))
  