from flask import Blueprint, render_template, request, redirect, url_for, flash
from flask_login import login_user, logout_user, login_required, current_user
from werkzeug.security import check_password_hash
from app.models import User, db, PasswordResetToken
from app.routes.reset_password import RequestResetForm, ResetPasswordForm
from flask_mail import Message
from app.routes.mail import mail
from app.utils.token import generate_reset_token, verify_reset_token
from datetime import datetime
import re
from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, BooleanField, SubmitField
from wtforms.validators import DataRequired, Email, EqualTo, Length

auth = Blueprint('auth', __name__)

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

class RegisterForm(FlaskForm):
    nickname = StringField('Nickname', validators=[DataRequired(), Length(min=3, max=32)])
    email = StringField('Email', validators=[DataRequired(), Email()])
    password = PasswordField('Password', validators=[DataRequired(), Length(min=8)])
    password2 = PasswordField('Confirm Password', validators=[DataRequired(), EqualTo('password')])
    submit = SubmitField('Register')

class ForgotPasswordForm(FlaskForm):
    email = StringField('Email', validators=[DataRequired(), Email()])
    submit = SubmitField('Request Password Reset')

@auth.route('/login', methods=['GET', 'POST'])
def login():
    """User login page"""
    if current_user.is_authenticated:
        return redirect(url_for('main.index'))
    
    form = LoginForm()
    if form.validate_on_submit():
        user = User.query.filter_by(email=form.email.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')
            if not next_page or not next_page.startswith('/'):
                next_page = url_for('community.index')
            flash(f'Welcome back, {user.nickname}!', 'success')
            return redirect(next_page)
        else:
            flash('Invalid email or password.', 'error')
    
    return render_template('auth/login.html', form=form)

@auth.route('/register', methods=['GET', 'POST'])
def register():
    """User registration page"""
    if current_user.is_authenticated:
        return redirect(url_for('main.index'))
    
    form = RegisterForm()
    if form.validate_on_submit():
        # Check if user already exists
        if User.query.filter_by(email=form.email.data).first():
            flash('Email address already registered.', 'error')
            return render_template('auth/register.html', form=form)
        
        if User.query.filter_by(nickname=form.nickname.data).first():
            flash('Nickname already taken.', 'error')
            return render_template('auth/register.html', form=form)
        
        # Validate password strength
        if not is_valid_password(form.password.data):
            flash('Password must be at least 8 characters long and contain at least one letter and one number.', 'error')
            return render_template('auth/register.html', form=form)
        
        # Create new user
        user = User(
            nickname=form.nickname.data,
            email=form.email.data
        )
        user.set_password(form.password.data)
        
        try:
            db.session.add(user)
            db.session.commit()
            login_user(user)
            flash('Registration successful! Welcome to the community!', 'success')
            return redirect(url_for('community.index'))
        except Exception as e:
            db.session.rollback()
            flash('An error occurred during registration. Please try again.', 'error')
    
    return render_template('auth/register.html', form=form)

@auth.route('/logout')
@login_required
def logout():
    """User logout"""
    logout_user()
    flash('You have been logged out.', 'info')
    return redirect(url_for('main.index'))

@auth.route('/forgot-password', methods=['GET', 'POST'])
def forgot_password():
    """Forgot password page - sends message to admin instead of email"""
    if current_user.is_authenticated:
        return redirect(url_for('main.index'))
    form = RequestResetForm()
    if form.validate_on_submit():
        user = User.query.filter_by(email=form.email.data).first()
        
        # Create password reset user if it doesn't exist
        reset_user = User.query.filter_by(email='reset_password@motoadventure.local').first()
        if not reset_user:
            reset_user = User(
                nickname='PasswordReset',
                email='reset_password@motoadventure.local',
                is_active=False  # This is a system user
            )
            reset_user.set_password('temp_password')  # Won't be used
            db.session.add(reset_user)
            db.session.commit()
        
        # Find admin support room
        from app.models import ChatRoom, ChatMessage
        admin_room = ChatRoom.query.filter_by(room_type='support').first()
        if not admin_room:
            # Create admin support room if it doesn't exist
            system_user = User.query.filter_by(email='system@motoadventure.local').first()
            admin_room = ChatRoom(
                name='Technical Support',
                description='Administrative support and password resets',
                room_type='support',
                is_private=False,
                is_active=True,
                created_by_id=system_user.id if system_user else 1
            )
            db.session.add(admin_room)
            db.session.commit()
        
        # Create the password reset message
        if user:
            message_content = f"A user with email '{user.email}' (nickname: {user.nickname}) needs their password to be changed. Please assist with password reset."
        else:
            message_content = f"Someone with email '{form.email.data}' requested a password reset, but no account exists with this email. Please check if this user needs assistance creating an account."
        
        reset_message = ChatMessage(
            content=message_content,
            room_id=admin_room.id,
            sender_id=reset_user.id,
            is_system_message=True
        )
        db.session.add(reset_message)
        
        # Update room activity
        admin_room.last_activity = datetime.utcnow()
        db.session.commit()
        
        flash('Your password reset request has been sent to administrators. They will contact you soon to help reset your password.', 'info')
        return redirect(url_for('auth.login'))
    return render_template('auth/forgot_password.html', form=form)

@auth.route('/change-password', methods=['POST'])
@login_required
def change_password():
    """Change user password"""
    current_password = request.form.get('current_password')
    new_password = request.form.get('new_password')
    confirm_password = request.form.get('confirm_password')
    
    # Validate inputs
    if not all([current_password, new_password, confirm_password]):
        flash('All password fields are required.', 'error')
        return redirect(url_for('community.profile'))
    
    # Check current password
    if not current_user.check_password(current_password):
        flash('Current password is incorrect.', 'error')
        return redirect(url_for('community.profile'))
    
    # Validate new password
    if len(new_password) < 6:
        flash('New password must be at least 6 characters long.', 'error')
        return redirect(url_for('community.profile'))
    
    # Check password confirmation
    if new_password != confirm_password:
        flash('New password and confirmation do not match.', 'error')
        return redirect(url_for('community.profile'))
    
    # Check if new password is different from current
    if current_user.check_password(new_password):
        flash('New password must be different from your current password.', 'error')
        return redirect(url_for('community.profile'))
    
    try:
        # Update password
        current_user.set_password(new_password)
        db.session.commit()
        flash('Password updated successfully!', 'success')
    except Exception as e:
        db.session.rollback()
        flash('An error occurred while updating your password. Please try again.', 'error')
    
    return redirect(url_for('community.profile'))

def is_valid_password(password):
    """Validate password strength"""
    if len(password) < 8:
        return False
    if not re.search(r'[A-Za-z]', password):
        return False
    if not re.search(r'\d', password):
        return False
    return True


class ResetPasswordWithTokenForm(FlaskForm):
    password = PasswordField('New Password', validators=[DataRequired(), Length(min=8)])
    password2 = PasswordField('Confirm New Password', validators=[DataRequired(), EqualTo('password')])
    submit = SubmitField('Reset Password')


@auth.route('/reset-password/<token>', methods=['GET', 'POST'])
def reset_password_with_token(token):
    """Reset password using admin-generated token"""
    # Find the token in database
    reset_token = PasswordResetToken.query.filter_by(token=token).first()
    
    if not reset_token:
        flash('Invalid or expired reset link.', 'error')
        return redirect(url_for('auth.login'))
    
    # Check if token is expired
    if reset_token.is_expired:
        flash('This reset link has expired. Please request a new one.', 'error')
        return redirect(url_for('auth.login'))
    
    # Check if token is already used
    if reset_token.is_used:
        flash('This reset link has already been used.', 'error')
        return redirect(url_for('auth.login'))
    
    form = ResetPasswordWithTokenForm()
    
    if form.validate_on_submit():
        user = reset_token.user
        
        # Validate password strength
        if not is_valid_password(form.password.data):
            flash('Password must be at least 8 characters long and contain both letters and numbers.', 'error')
            return render_template('auth/reset_password_with_token.html', form=form, token=token)
        
        # Update password
        user.set_password(form.password.data)
        
        # Mark token as used
        reset_token.used_at = datetime.utcnow()
        reset_token.user_ip = request.environ.get('REMOTE_ADDR')
        
        # Update request status
        if reset_token.request:
            reset_token.request.status = 'completed'
            reset_token.request.updated_at = datetime.utcnow()
        
        db.session.commit()
        
        flash('Your password has been reset successfully! You can now log in with your new password.', 'success')
        return redirect(url_for('auth.login'))
    
    return render_template('auth/reset_password_with_token.html', form=form, token=token, user=reset_token.user)