pypila

from __future__ import unicode_literals

from flask import (
    Flask, render_template, url_for, redirect, request, session, flash
)
from flask.ext.script import Manager, Server
from flask.ext.bootstrap import Bootstrap

import forms

app = Flask(__name__)
server = Server(host='0.0.0.0', port='5000')
app.secret_key = 'Some mega ultra hiper secret key'
manager = Manager(app)
manager.add_command('runserver', server)
bootstrap = Bootstrap(app)

IMAGE_EXTENSIONS = ['.jpg', '.jpeg', '.gif', '.png']


@app.route('/')
def index():
    """
        if user is logged:
            render template index.html with user name in "name" parameter
        else:
            just render template index.html
    """
    form = forms.LoginForm()
    if 'username' in session:
        return render_template("index.html",name=session['username'])
    else:
        return render_template("index.html")

@app.route('/browse')
def browse():
    """
        render template with get_images function in "images" parameter
    """
    return render_template("browse.html",images=get_images())

@app.route('/register', methods=['GET', 'POST'])
def register():
    """
        function to register users.
        Checks if user already exists in users.txt using user_exists function.
        if user exists:
            flash message: "Sorry but user with given username already exists"
            and redirect to register.html
        Rendered based on RegistrationForm.
    """
    form = forms.RegistrationForm(request.form)
    if request.method == 'POST':
        if user_exists(form.username.data):
            flash('Sorry but user with given username already exists')
            return redirect(url_for('register'))
        else:
            with open('users.txt', 'a+') as f:
                f.write('\n'+form.username.data+':'+form.password.data)
            flash('User added')
            return redirect(url_for('login'))
    return render_template('register.html', form=form)

@app.route('/login', methods=['GET', 'POST'])
def login():
    """
        if user provide corrected login and password combination:
            flash message: "You have been logged successfully"
            and redirect to index.html
        else:
            render login.html template with LoginForm as "form" parameter
    """
    form = forms.LoginForm()
    if request.method == 'POST':

        if user_exists(request.form['username']) and validate_password(request.form['username'],request.form['password']):
            session['username'] = request.form['username']
            flash('You have been logged successfully')
            return redirect(url_for('index'))
        else:
            flash('User not exists or wrong password')
            return render_template("login.html",form=form)
    else:
        return render_template("login.html",form=form)



@app.route('/logout')
def logout():
    """
        Pop user from session, send flash message:
        "You have been logged out succesfully"
        and redirect to index page
    """

    session['username'] = ""
    flash('You have been logged successfully')
    return redirect(url_for('index'))

def validate_password(username, password):
    """
        Helper function for login().
        Checks if username and password combination match to data in users.txt
        @param username: user name
        @param password: user password
        @return: True or False
    """
    u = {}
    with open('users.txt', 'r') as f:
        for line in f:
            (key,val)=line.split(":")
            u.setdefault(key, val)
    if u[username]==password:
        return True
    else:
        return False

def user_exists(username):
    """
        Helper function for register().
        Checks if user exists in users.txt
        @param username: user name
        @return: True or False
    """
    with open('users.txt', 'r') as f:
        users = f.read()

    if username in users:
        return True
    else:
        return False

def get_images():
    """
        Helper function for browse()
        Creates reversed list with urls to images taken from images.txt file
    """
    ob=[]
    with open('images.txt', 'r') as f:
        for line in f:
            ob.append(line)
    return sorted(ob,reverse=True)

@app.errorhandler(404)
def page_not_found(e):
    """
        render template 404.html and send 404 http status
    """
    return render_template("404.html"),404

@app.errorhandler(500)
def internal_server_error(e):
    """
        render template 500.html and send 500 http status
    """
    return render_template("500.html"),500

@app.route('/add', methods=['GET', 'POST'])
def add():
    """
        Render add.html with forms.AdditionForm(request.form)as "form" param
        if form is correct open images.txt file and add url to next line, then
        flash message: 'Photo added succesfully' and redirect to browse.html
    """
    form = forms.AdditionForm()

    if request.form:
        with open('images.txt', 'a+') as f:
            f.write('\n'+request.form['url'])
            flash('Photo added succesfully')
            return redirect(url_for('browse'))
    else:
        return render_template("add.html",form=forms.AdditionForm(request.form))


if __name__ == '__main__':
    manager.run()