from flask import render_template, flash, redirect, url_for, request
from werkzeug.urls import url_parse
from app import app, db
from app.auth.forms import LoginForm, RegistrationForm, EditProfileForm, PostForm, ResetPasswordRequestForm
from app.email import send_password_reset_email

from flask_login import current_user, login_user, logout_user, login_required
from app.models import User, Post
from datetime import datetime
from app.auth.forms import ResetPasswordForm


@app.route('/', methods=['GET', 'POST'])
@app.route('/index', methods=['GET', 'POST'])
@login_required
def index():
    # user = {'username': 'Trung Anh'}
    # posts = [
    #     {
    #         'author': {'username': 'Nguyen'},
    #         'body': 'Demo Flask with some seconds'
    #     },
    #     {
    #         'author': {'username': 'Nam'},
    #         'body': 'Code back-end for production'
    #     }
    # ]

    # ==== FORM POST ====
    form = PostForm()
    if form.validate_on_submit():
        post = Post(body=form.post.data, author=current_user)
        db.session.add(post)
        db.session.commit()
        flash('Your post is now live!')
        return redirect(url_for('index'))
    page = request.args.get('page', 1, type=int)
    # posts = current_user.followed_posts().all()

    # Tham số 1: số thứ tự trang hiện tại, bắt đầu từ 1
    # Tham số 2: Số đơn vị trên một trang
    # Tham số 3: Cờ hiệu lỗi, True - 404, False trả về rỗng
    posts = current_user.followed_posts().paginate(
        page, app.config['POSTS_PER_PAGE'], False)
    next_url = url_for('index', page=posts.next_num) \
        if posts.has_next else None
    prev_url = url_for('index', page=posts.prev_num) \
        if posts.has_prev else None
    return render_template('index.html', title='Home Page', form=form, posts=posts.items,
                           next_url=next_url, prev_url=prev_url)


@app.route('/login', methods=['GET', 'POST'])
def login():
    if current_user.is_authenticated:
        return redirect(url_for('index'))
    form = LoginForm()
    if form.validate_on_submit():
        user = User.query.filter_by(username=form.username.data).first()
        if user is None or not user.check_password(form.password.data):
            flash('Invalid username or password')
            return redirect(url_for('login'))
        # flash('Yeu cau dang nhap tu user {}, remember_me={}'.format(
        #     form.username.data, form.remember_me.data
        # ))
        login_user(user, remember=form.remember_me.data)
        next_page = request.args.get('next')
        if not next_page or url_parse(next_page).netloc != '':
            next_page = url_for('index')
        return redirect(next_page)
        # return redirect(url_for('index'))
    return render_template('auth/login.html', title='Sign In', form=form)


@app.route('/logout')
def logout():
    logout_user()
    return redirect(url_for('index'))


@app.route('/register', methods=['GET', 'POST'])
def register():
    if current_user.is_authenticated:
        return redirect(url_for('index'))
    form = RegistrationForm()
    if form.validate_on_submit():
        user = User(username=form.username.data, email=form.email.data)
        user.set_password(form.password.data)
        db.session.add(user)
        db.session.commit()
        flash('Congratulations, you are now a registered user!')
        return redirect(url_for('login'))
    return render_template('auth/register.html', title='Register', form=form)


@app.route('/user/<username>')
@login_required
def user(username):
    user = User.query.filter_by(username=username).first_or_404()
    # posts = [
    #     {'author': user, 'body': 'Bài viết #1'},
    #     {'author': user, 'body': 'Bài viết #2'}
    # ]
    # return render_template('user.html', user=user, posts=posts)
    page = request.args.get('page', 1, type=int)
    posts = user.posts.order_by(Post.timestamp.desc()).paginate(
        page, app.config['POSTS_PER_PAGE'], False)
    next_url = url_for('user', username=user.username, page=posts.next_num) \
        if posts.has_next else None
    prev_url = url_for('user', username=user.username, page=posts.prev_num) \
        if posts.has_prev else None
    return render_template('user.html', user=user, posts=posts.items,
                           next_url=next_url, prev_url=prev_url)


@app.before_request
def before_request():
    if current_user.is_authenticated:
        current_user.last_seen = datetime.utcnow()
        db.session.commit()


@app.route('/edit_profile', methods=['GET', 'POST'])
@login_required
def edit_profile():
    form = EditProfileForm(current_user.username)
    if form.validate_on_submit():
        current_user.username = form.username.data
        current_user.about_me = form.about_me.data
        db.session.commit()
        flash('Your changes have been saved.')
        return redirect(url_for('edit_profile'))
    elif request.method == 'GET':
        form.username.data = current_user.username
        form.about_me.data = current_user.about_me
    return render_template('edit_profile.html', title='Edit Profile', form=form)


@app.route('/follow/<username>')
@login_required
def follow(username):
    user = User.query.filter_by(username=username).first()
    if user is None:
        flash('User {} not found.'.format(username))
        return redirect(url_for('index'))
    if user == current_user:
        flash('You cannot follow yourself!')
        return redirect(url_for('user', username=username))
    current_user.follow(user)
    db.session.commit()
    flash('You are following {}!'.format(username))
    return redirect(url_for('user', username=username))


@app.route('/unfollow/<username>')
@login_required
def unfollow(username):
    user = User.query.filter_by(username=username).first()
    if user is None:
        flash('User {} not found.'.format(username))
        return redirect(url_for('index'))
    if user == current_user:
        flash('You cannot unfollow yourself!')
        return redirect(url_for('user', username=username))
    current_user.unfollow(user)
    db.session.commit()
    flash('you are not following {}'.format(username))
    return redirect(url_for('user', username=username))


@app.route('/explore')
@login_required
def explore():
    page = request.args.get('page', 1, type=int)
    # posts = Post.query.order_by(Post.timestamp.desc()).all()
    posts = Post.query.order_by(Post.timestamp.desc()).paginate(
        page, app.config['POSTS_PER_PAGE'], False
    )  # trả về đối tượng pagination
    # url_for: cho phép bạn sử dụng các tham số bất kỳ dưới dạng các từ khóa
    # (ví dụ như tham số page trong đoạn mã trên)
    # và nếu các tham số này không được dùng trực tiếp trong URL,
    # Flask sẽ thêm các tham số này vào phần query string trong URL
    # (phần tham số phía sau dấu ? trong URL)
    next_url = url_for('explore', page=posts.next_num) \
        if posts.has_next else None
    prev_url = url_for('explore', page=posts.prev_num) \
        if posts.has_prev else None
    return render_template('index.html', title='Explore', posts=posts.items,
                           next_url=next_url, prev_url=prev_url)


@app.route('/reset_password_request', methods=['GET', 'POST'])
def reset_password_request():
    if current_user.is_authenticated:
        return redirect(url_for('index'))
    form = ResetPasswordRequestForm()
    if form.validate_on_submit():
        user = User.query.filter_by(email=form.email.data).first()
        if user:
            send_password_reset_email(user)
        flash('Check your email for the instructions to reset your password')
        return redirect(url_for('login'))
    return render_template('auth/reset_password_request.html',
                           title='Reset Password', form=form)

@app.route('/reset_password/<token>', methods=['GET', 'POST'])
def reset_password(token):
    if current_user.is_authenticated:
        return redirect(url_for('index'))
    user = User.verify_reset_password_token(token)
    if not user:
        return redirect(url_for('index'))
    form = ResetPasswordForm()
    if form.validate_on_submit():
        user.set_password(form.password.data)
        db.session.commit()
        flash('Your password has been reset.')
        return redirect(url_for('login'))
    return render_template('auth/reset_password.html', form=form)
