from cs50 import SQL
from flask import Flask, flash, redirect, render_template, request, session
from flask_session import Session
from werkzeug.security import check_password_hash, generate_password_hash

from helpers import apology, login_required

# Configure application
app = Flask(__name__)

# Configure session to use filesystem (instead of signed cookies)
app.config["SESSION_PERMANENT"] = False
app.config["SESSION_TYPE"] = "filesystem"
Session(app)

# Configure CS50 Library to use SQLite database
db = SQL("sqlite:///eeao.db")


@app.after_request
def after_request(response):
    """Ensure responses aren't cached"""
    response.headers["Cache-Control"] = "no-cache, no-store, must-revalidate"
    response.headers["Expires"] = 0
    response.headers["Pragma"] = "no-cache"
    return response


@app.route("/")
@login_required
def index():
    # Get actual cash of the logged-in user
    user = db.execute("SELECT * FROM users WHERE id = ?", session["user_id"])

    return render_template("index.html", user=user[0])


@app.route("/login", methods=["GET", "POST"])
def login():
    """Log user in"""

    # Forget any user_id
    session.clear()

    # User reached route via POST (as by submitting a form via POST)
    if request.method == "POST":
        # Ensure username was submitted
        if not request.form.get("username"):
            return apology("must provide username", 400)
        username = request.form.get("username")

        # Ensure password was submitted
        if not request.form.get("password"):
            return apology("must provide password", 400)
        password = request.form.get("password")

        # Query database for username
        rows = db.execute("SELECT * FROM users WHERE username = ?", username)

        # Ensure username exists and password is correct
        if len(rows) != 1 or not check_password_hash(rows[0]["hash"], password):
            return apology("invalid username and/or password", 400)

        # Remember which user has logged in
        session["user_id"] = rows[0]["id"]

        # Redirect user to home page
        return redirect("/")

    # User reached route via GET (as by clicking a link or via redirect)
    else:
        return render_template("login.html")


@app.route("/logout")
def logout():
    """Log user out"""

    # Forget any user_id
    session.clear()

    # Redirect user to login form
    return redirect("/")


@app.route("/register", methods=["GET", "POST"])
def register():
    """Register user"""
    # User reached route via POST (as by submitting a form via POST)
    if request.method == "POST":
        username = request.form.get("username")
        # Ensure username was submitted
        if not username:
            return apology("must provide username", 400)
        # Check if user already existing
        if db.execute("SELECT * FROM users WHERE username = ?", username):
            return apology("user already exists", 400)

        password = request.form.get("password")
        # Ensure password was submitted
        if not password:
            return apology("must provide password", 400)

        confirmation = request.form.get("confirmation")
        # Ensure password was submitted
        if not confirmation:
            # Query database for username
            return apology("must provide confirmation", 400)

        # Ensure password is identical with confirmation
        if password != confirmation:
            return apology("password and confirmation does not match", 400)

        # Add user to db
        password_hash = generate_password_hash(password)
        db.execute("INSERT INTO users (username, hash) VALUES(?, ?)", username, password_hash)

        # Redirect user to home page
        return redirect("/")

    # User reached route via GET (as by clicking a link or via redirect)
    else:
        return render_template("register.html")