import datetime
import hashlib

from flask import Flask, render_template, redirect, url_for, request
from flask_login import login_required, LoginManager, login_user, logout_user, current_user

from models.Habit import Habit
from models.HabitList import HabitList
from models.HabitTrackings import HabitTrackings
from models.User import User
from utils import anonymous_required

# Create a new Flask instance
app = Flask(__name__)
app.secret_key = 'PSSSSSHHHT!'

# Initialize the Flask-Login extension
login_manager = LoginManager()
login_manager.login_view = 'login'
login_manager.init_app(app)


@login_manager.user_loader
def load_user(user_id):
    return User.get(user_id)


@app.context_processor
def inject_user():
    return dict(user=current_user)


@app.route('/login')
@anonymous_required
def login():
    return render_template('auth/login.html', errors={})


@app.route('/signup')
@anonymous_required
def signup():
    return render_template('auth/signup.html', errors={})


@app.route('/login', methods=['POST'])
def login_post():
    email = request.form.get('email')
    password = request.form.get('password')

    # Check for errors
    errors = {}
    if not email:
        errors['email'] = 'Die E-Mail Adresse ist erforderlich.'
    if not password:
        errors['password'] = 'Das Passwort ist erforderlich.'

    # Check if user exists
    user = User.get_by_email(email)

    if not user:
        errors['email'] = 'E-Mail Adresse nicht gefunden.'
    elif user.password is None or hashlib.sha256(password.encode()).hexdigest() != user.password:
        errors['password'] = 'Das Passwort ist falsch.'

    if errors:
        return render_template(
            'auth/login.html',
            email=email,
            password=password,
            errors=errors
        )

    login_user(user)

    # Redirect to login page
    return redirect(url_for('index'))


@app.route('/signup', methods=['POST'])
def signup_post():
    email = request.form.get('email')
    name = request.form.get('name')
    password = request.form.get('password')

    # Check for errors
    errors = {}
    if not email:
        errors['email'] = 'Die E-Mail Adresse ist erforderlich.'
    if not name:
        errors['name'] = 'Der Name ist erforderlich.'
    if not password:
        errors['password'] = 'Das Passwort ist erforderlich.'

    if errors:
        return render_template(
            'auth/signup.html',
            email=email,
            name=name,
            password=password,
            errors=errors
        )

    # Save user to database. Maybe log the user in directly.
    user = User.create(name, email, password)
    login_user(user)

    # Redirect to login page
    return redirect(url_for('index'))


@app.route('/logout')
@login_required
def logout():
    # Log out functionality
    logout_user()

    return redirect(url_for('index'))


# Create a new route
@app.route('/')
def index():
    if current_user.is_authenticated:
        habit_lists = current_user.get_habitLists()
        name = "Hallo " + current_user.name
    else:
        habit_lists = []
        name = "Bitte melde dich an."

    # Sort habits by whether they have been checked today and then by slot
    for habit_list in habit_lists:
        habit_list.habits = sorted(habit_list.get_habits(), key=lambda habit: (not habit.checked, habit.slot))

    return render_template(
        'index.html',
        title=name,
        utc_dt=datetime.datetime.now().strftime("%d.%m.%Y %H:%M %A"),
        habit_lists=habit_lists,
        errors={},
    )


@app.route('/habit')
@login_required
def habit_creation():
    return render_template(
        'habit.html',
        title='Erstelle ein Habit',
        unit="Woche",
        errors={},
    )


@app.route('/habit', methods=['POST'])
@login_required
def habit_create():
    name = request.form.get('name')
    note = request.form.get('note')
    times = request.form.get('times')
    unit = request.form.get('unit')
    list_id = request.form.get('list_query')

    # Check for errors
    errors = {}
    if not name:
        errors['name'] = 'Der Name ist erforderlich.'
    if not times:
        errors['times'] = 'Die Anzahl ist erforderlich.'
    if not note:
        note = ''
    if not unit:
        errors['unit'] = 'Die Einheit ist erforderlich.'
    if not list_id:
        errors['list_query'] = 'Die Habitliste ist erforderlich.'

    # Check if times is an integer
    try:
        times = int(times)

        # Check that times is greater than 0
        if times <= 0:
            errors['times'] = 'Die Anzahl muss größer als 0 sein.'
    except ValueError:
        errors['times'] = 'Die Anzahl muss eine Zahl sein.'

    # Check that unit is valid
    if unit not in ['Tag', 'Woche', 'Monat', 'Jahr']:
        errors['unit'] = 'Die Einheit ist ungültig.'

    # check if list_id is an int
    try:
        list_id = int(list_id)
    except ValueError:
        errors['list_query'] = 'Die Anzahl muss eine Zahl sein.'

    if errors:
        return render_template(
            'habit.html',
            title='Erstelle ein Habit',
            name=name,
            note=note,
            times=times,
            unit=unit,
            errors=errors,
            list_id=list_id
        )

    # Map unit to integer
    if unit == 'Tag':
        unit = 0
    elif unit == 'Woche':
        unit = 1
    elif unit == 'Monat':
        unit = 2
    elif unit == 'Jahr':
        unit = 3
    else:
        unit = 1

    # Save habit to database
    habit = Habit.create(list_id, name, times, note, unit)

    # Back to index
    return redirect(url_for('index'))


@app.route('/habit-list')
@login_required
def habit_list_creation():
    return render_template(
        'habit-list.html',
        title='Erstelle eine Habitliste',
        errors={},
    )


@app.route('/habit-list', methods=['POST'])
@login_required
def habit_list_create():
    name = request.form.get('name')
    description = request.form.get('description')

    # Check for errors
    errors = {}
    if not name:
        errors['name'] = 'Der Name ist erforderlich.'
    if not description:
        note = ''

    if errors:
        return render_template(
            'habit-list.html',
            title='Erstelle eine Habitliste',
            name=name,
            description=description,
            errors=errors
        )

    # Save habit to database
    habit = HabitList.create(current_user.id, name, description)

    # Back to index
    return redirect(url_for('index'))


@app.route('/profile')
@login_required
def profile():
    return render_template(
        "profile.html",
        name=current_user.name,
        email=current_user.email,
        errors={}
    )


@app.route('/profile', methods=['POST'])
@login_required
def profile_change():
    newName = request.form.get('newName')
    newEmail = request.form.get('newEmail')
    newPassword = request.form.get('newPassword')
    oldPassword = request.form.get('oldPassword')

    # Check for errors
    errors = {}
    if not newName:
        errors['newName'] = 'Der Name ist erforderlich.'

    if not newEmail:
        errors['newEmail'] = 'Die E-Mail Adresse ist erforderlich.'

    if not oldPassword:
        errors['oldPassword'] = 'Du musst dein aktuelles Passwort angeben.'
    else:
        if hashlib.sha256(oldPassword.encode()).hexdigest() != current_user.password:
            errors['oldPassword'] = 'Das Passwort ist falsch.'

    if errors:
        return render_template(
            "profile.html",
            name=current_user.name,
            email=current_user.email,
            errors=errors
        )

    # Update user
    current_user.name = newName
    current_user.email = newEmail
    if newPassword:
        current_user.password = hashlib.sha256(newPassword.encode()).hexdigest()
    current_user.update()

    # Back to profile
    return render_template(
        "profile.html",
        name=current_user.name,
        email=current_user.email,
        errors={}
    )


@app.route('/check', methods=['POST'])
@login_required
def check_habit():
    habit_id = request.get_json()["habitId"]

    habit = Habit.get(habit_id)

    if habit is None:
        return {"error": "Habit not found"}

    # Check if habit belongs to user
    users = habit.habit_list().get_users()
    if current_user not in users:
        return {"error": "Habit does not belong to user"}

    trackings = habit.get_habitTrackings()

    # Check if habit has been tracked today
    delete_tracking = None
    for tracking in trackings:
        if tracking.created_at.date() == datetime.date.today():
            delete_tracking = tracking

    if not delete_tracking:
        HabitTrackings.create(habit_id, 1)
    else:
        delete_tracking.delete()

    # Update habit
    habit.fill_statistics()

    return {
        "habitId": habit_id,
        "unchecked": not delete_tracking,
        "percentage": habit.percentage,
    }

@app.route('/delete', methods=['POST'])
@login_required
def delete_habit():
    habit_id = request.get_json()["habitId"]

    habit = Habit.get(habit_id)

    if habit is None:
        return {"error": "Habit not found"}

    # Check if habit belongs to user
    if current_user not in habit.habit_list().get_users():
        return {"error": "Habit does not belong to user"}

    habit.delete()
    return {}


@app.route('/reorder', methods=['POST'])
@login_required
def reorder_habits():
    new_index = request.get_json()["newIndex"]+1
    habit = Habit.get(request.get_json()["habitId"])

    if habit is None:
        return {"error": "Habit not found"}

    # Check if habit belongs to user
    users = habit.habit_list().get_users()
    if current_user not in users:
        return {"error": "Habit does not belong to user"}

    habit.update_slot(new_index)

    return {}


# Run the application
if __name__ == '__main__':
    app.run(port=5000, debug=True)