from flask import Blueprint, render_template, redirect, url_for, flash, request
from flask_login import login_user, logout_user, login_required, current_user
from werkzeug.urls import url_parse
from models import db, User, SiteConfig
from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, BooleanField, SubmitField
from wtforms.validators import DataRequired, Email, EqualTo, Length, ValidationError
from oauth import google_bp

auth_bp = Blueprint('auth', __name__)

class LoginForm(FlaskForm):
    username = StringField('Username', validators=[DataRequired()])
    password = PasswordField('Password', validators=[DataRequired()])
    remember_me = BooleanField('Remember Me')
    submit = SubmitField('Sign In')

class RegistrationForm(FlaskForm):
    username = StringField('Username', validators=[DataRequired(), Length(min=3, max=64)])
    email = StringField('Email', validators=[DataRequired(), Email()])
    password = PasswordField('Password', validators=[DataRequired(), Length(min=8)])
    confirm_password = PasswordField('Confirm Password', validators=[DataRequired(), EqualTo('password')])
    submit = SubmitField('Register')
    
    def validate_username(self, username):
        user = User.query.filter_by(username=username.data).first()
        if user:
            raise ValidationError('Username already taken. Please choose a different one.')
    
    def validate_email(self, email):
        user = User.query.filter_by(email=email.data).first()
        if user:
            raise ValidationError('Email already registered. Please use a different one.')

@auth_bp.route('/login', methods=['GET', 'POST'])
def login():
    if current_user.is_authenticated:
        return redirect(url_for('user.home'))
    
    form = LoginForm()
    if form.validate_on_submit():
        user = User.query.filter_by(username=form.username.data).first()
        if user and user.check_password(form.password.data):
            login_user(user, remember=form.remember_me.data)
            next_page = request.args.get('next')
            return redirect(next_page or url_for('user.home'))
        flash('Invalid username or password', 'danger')
    
    # Check if Google OAuth is configured
    google_configured = google_bp.client_id is not None
    
    return render_template('auth/login.html', form=form, google_configured=google_configured)

@auth_bp.route('/logout')
@login_required
def logout():
    logout_user()
    flash('You have been logged out.', 'info')
    return redirect(url_for('user.home'))

@auth_bp.route('/register', methods=['GET', 'POST'])
def register():
    if current_user.is_authenticated:
        return redirect(url_for('user.home'))
    
    # Check if registration is enabled
    registration_enabled = SiteConfig.get_setting('registration_enabled', 'true') == 'true'
    if not registration_enabled:
        flash("User registration is currently disabled", "warning")
        return redirect(url_for('auth.login'))
    
    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('Registration successful! You can now log in.', 'success')
        return redirect(url_for('auth.login'))
    
    return render_template('auth/register.html', form=form)