import datetime
import email.message
import logging
import os
import smtplib

import psycopg
import psycopg.rows

from flask import (
    Flask, session, redirect, url_for, request, render_template,
    g, abort
)

import config

logging.basicConfig(format="%(asctime)s %(levelname)s %(name)s %(lineno)d | %(message)s", level=logging.DEBUG)

app = Flask(__name__)
app.secret_key = config.secret_key
app.config["PERMANENT_SESSION_LIFETIME"] = datetime.timedelta(days=92)

log = logging.getLogger(__name__)

@app.route("/")
def home():
    log.debug("in home")
    log.debug("session = %s", session)
    if "user" not in session:
        return redirect(url_for('register'))
    return render_template("home.html")

@app.route("/register", methods=["GET", "POST"])
def register():
    log.debug("in register")
    if request.method == "GET":
        return render_template("register.html")
    email_address = request.form.get("email", "")
    if "@" not in email_address:
        flash("Das schaut nicht wie eine E-Mail-Adresse aus")
    csr = get_cursor()
    csr.execute("select * from bod where email = %s", (email_address,))
    r = csr.fetchone()
    if r:
        if r.key:
            key = r.key
        else:
            key = os.urandom(8).hex()
            csr.execute(
                    "update bod set key = %s, keychange = now() where email = %s",
                    (key, email_address,))
    else:
        key = os.urandom(8).hex()
        csr.execute(
                "insert into bod(email, key, keychange) values(%s, %s, now())",
                (email_address, key,))
    confirmation_url = url_for("confirm",
                                target=request.form["target"],
                                key=key)
    send_mail(email_address, confirmation_url)
    return render_template("wait_for_confirmation.html")

@app.route("/confirm")
def confirm():
    csr = get_cursor()
    csr.execute("select * from bod where key = %s", (request.args["key"],))
    bod = csr.fetchone()
    if not bod:
        return render_template("wrong_key.html")
    session["user"] = { "id": bod.id, "email": bod.email}
    return redirect(request.args["target"])

@app.route("/vote/<string:key>")
def vote(key):
    log.debug("session = %s", session)
    csr = get_cursor()
    csr.execute("select * from meet where key = %s", (key,))
    meet = csr.fetchone()
    if not meet:
        abort(404)

    csr.execute(
            """
            select d.id, d.date, d.display, position
            from date d left join date_vote v on d.id = v.date and v.bod = %s
            where meet = %s order by position, d.date
            """,
            (session["user"]["id"], meet.id,))
    dates = csr.fetchall()

    csr.execute(
            """
            select d.id, d.time, d.display, position
            from time d left join time_vote v on d.id = v.time and v.bod = %s
            where meet = %s order by position, d.time
            """,
            (session["user"]["id"], meet.id,))
    times = csr.fetchall()

    csr.execute(
            """
            select d.id, d.name, position
            from place d left join place_vote v on d.id = v.place and v.bod = %s
            where meet = %s order by position, d.name
            """,
            (session["user"]["id"], meet.id,))
    places = csr.fetchall()

    return render_template("vote.html",
                meet=meet, dates=dates, times=times, places=places)

@app.post("/vote/date")
def vote_date():
    log.debug("form = %s", request.form)
    date_ids = request.form.getlist("date")

    csr = get_cursor()
    # Retrieve the meet.id from the date ids. This also ensures that all the
    # dates refer to the same meet.
    csr.execute("select distinct meet from date where id = any (%s)",
        (date_ids,))
    r = csr.fetchall()
    if len(r) != 1:
        # this should never happen. Is the client messing around?
        log.warning("Date ids %s map to meets %s", date_ids, r)
        abort(400)
    meet_id = r[0].meet

    csr.execute("delete from date_vote where date = any (%s)", (date_ids,))
    for pos, date_id in enumerate(date_ids):
        csr.execute(
                "insert into date_vote(date, bod, position) values(%s, %s, %s)",
                (date_id, session["user"]["id"], pos)
            )
    # XXX - (almost) duplicate
    csr.execute(
            """
            select d.id, d.date, d.display, position
            from date d left join date_vote v on d.id = v.date and v.bod = %s
            where meet = %s order by position, d.date
            """,
            (session["user"]["id"], meet_id,))
    dates = csr.fetchall()
    return render_template("date_vote_fragment.html", dates=dates)

@app.post("/vote/time")
def vote_time():
    log.debug("form = %s", request.form)
    time_ids = request.form.getlist("time")

    csr = get_cursor()
    # Retrieve the meet.id from the time ids. This also ensures that all the
    # times refer to the same meet.
    csr.execute("select distinct meet from time where id = any (%s)",
        (time_ids,))
    r = csr.fetchall()
    if len(r) != 1:
        # this should never happen. Is the client messing around?
        log.warning("Time ids %s map to meets %s", time_ids, r)
        abort(400)
    meet_id = r[0].meet

    csr.execute("delete from time_vote where time = any (%s)", (time_ids,))
    for pos, time_id in enumerate(time_ids):
        csr.execute(
                "insert into time_vote(time, bod, position) values(%s, %s, %s)",
                (time_id, session["user"]["id"], pos)
            )
    # XXX - (almost) duplicate
    csr.execute(
            """
            select d.id, d.time, d.display, position
            from time d left join time_vote v on d.id = v.time and v.bod = %s
            where meet = %s order by position, d.time
            """,
            (session["user"]["id"], meet_id,))
    times = csr.fetchall()
    return render_template("time_vote_fragment.html", times=times)

@app.post("/vote/place")
def vote_place():
    log.debug("form = %s", request.form)
    place_ids = request.form.getlist("place")

    csr = get_cursor()
    # Retrieve the meet.id from the place ids. This also ensures that all the
    # places refer to the same meet.
    csr.execute("select distinct meet from place where id = any (%s)",
        (place_ids,))
    r = csr.fetchall()
    if len(r) != 1:
        # this should never happen. Is the client messing around?
        log.warning("Place ids %s map to meets %s", place_ids, r)
        abort(400)
    meet_id = r[0].meet

    csr.execute("delete from place_vote where place = any (%s)", (place_ids,))
    for pos, place_id in enumerate(place_ids):
        csr.execute(
                "insert into place_vote(place, bod, position) values(%s, %s, %s)",
                (place_id, session["user"]["id"], pos)
            )
    # XXX - (almost) duplicate
    csr.execute(
            """
            select d.id, d.name, position
            from place d left join place_vote v on d.id = v.place and v.bod = %s
            where meet = %s order by position, d.name
            """,
            (session["user"]["id"], meet_id,))
    places = csr.fetchall()
    return render_template("place_vote_fragment.html", places=places)


def send_mail(email_address, confirmation_url):
    msg = email.message.EmailMessage()
    msg["From"] ="noreply@hjp.at"
    msg["To"] = email_address
    msg["Subject"] = "MEEAT confirmation"
    body = confirmation_url # Really minimalistic
    msg.set_content(body)
    mta = smtplib.SMTP(host="localhost")
    mta.send_message(msg)

def get_cursor():
    db = get_db()
    csr = db.cursor(row_factory=psycopg.rows.namedtuple_row)
    return csr

def get_db():
    if "db" not in g:
        g.db = psycopg.connect(dbname=config.dbname)
    return g.db

@app.teardown_appcontext
def teardown_db(exception):
    log.debug("in teardown_db: exception = %s", exception)
    db = g.pop('db', None)
    if db is not None:
        if not exception:
            try:
                db.commit()
            except:
                pass
        db.rollback()
        db.close()