"""
Database Models
SQLAlchemy models for the application.
"""

import uuid
from datetime import datetime
from flask_login import UserMixin
from flask_bcrypt import Bcrypt
from database import db

# Initialize bcrypt
bcrypt = Bcrypt()


class User(UserMixin, db.Model):
    """User model with bcrypt password hashing"""

    __tablename__ = 'users'

    # Primary fields
    id = db.Column(db.String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    username = db.Column(db.String(80), unique=True, nullable=False, index=True)
    email = db.Column(db.String(120), unique=True, nullable=False, index=True)
    password_hash = db.Column(db.String(128), nullable=True)  # Nullable for OAuth users
    
    # OAuth fields
    auth0_id = db.Column(db.String(255), unique=True, nullable=True, index=True)

    # User attributes
    is_admin = db.Column(db.Boolean, default=False, nullable=False)
    is_active = db.Column(db.Boolean, default=True, nullable=False)

    # Profile
    profile_picture_url = db.Column(db.String(255), nullable=True)

    # Timestamps
    created_at = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
    last_login = db.Column(db.DateTime, nullable=True)

    # User settings (JSON stored as text)
    settings = db.Column(db.Text, default='{}')

    def __init__(self, username, email, password=None, is_admin=False, auth0_id=None):
        """
        Initialize a new user.

        Args:
            username: Unique username
            email: Unique email address
            password: Plain text password (will be hashed) - optional for OAuth users
            is_admin: Whether user is admin (default False)
            auth0_id: Auth0 user ID for OAuth users (optional)
        """
        # Validate inputs
        if not username or not isinstance(username, str) or len(username) > 80:
            raise ValueError("Invalid username")
        if not email or not isinstance(email, str) or len(email) > 120:
            raise ValueError("Invalid email")
        if password is not None and (not isinstance(password, str) or len(password) < 1):
            raise ValueError("Invalid password")
        if password is None and auth0_id is None:
            raise ValueError("Either password or auth0_id must be provided")
        
        self.id = str(uuid.uuid4())
        self.username = username.strip()
        self.email = email.strip().lower()
        self.auth0_id = auth0_id
        
        if password:
            self.set_password(password)
        else:
            self.password_hash = None  # OAuth users don't have passwords
            
        self.is_admin = bool(is_admin)
        self.is_active = True
        self.created_at = datetime.utcnow()

    def set_password(self, password):
        """
        Hash and set user password using bcrypt.

        Args:
            password: Plain text password
        """
        self.password_hash = bcrypt.generate_password_hash(password).decode('utf-8')

    def check_password(self, password):
        """
        Verify password against stored hash.

        Args:
            password: Plain text password to check

        Returns:
            True if password matches, False otherwise
        """
        return bcrypt.check_password_hash(self.password_hash, password)

    def update_last_login(self):
        """Update the last login timestamp"""
        self.last_login = datetime.utcnow()
        db.session.commit()

    def get_id(self):
        """Required by Flask-Login"""
        return self.id

    def __repr__(self):
        return f'<User {self.username}>'


class Session(db.Model):
    """User session model for tracking active sessions"""

    __tablename__ = 'user_sessions'

    session_id = db.Column(db.String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    user_id = db.Column(db.String(36), db.ForeignKey('users.id'), nullable=False)
    created_at = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
    expires_at = db.Column(db.DateTime, nullable=False)

    # Relationship
    user = db.relationship('User', backref=db.backref('sessions', lazy=True))

    def __repr__(self):
        return f'<Session {self.session_id} for user {self.user_id}>'


class PollSource(db.Model):
    """Source polling configuration"""

    __tablename__ = 'poll_sources'

    id = db.Column(db.String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    platform = db.Column(db.String(50), nullable=False, index=True)  # reddit, hackernews, etc.
    source_id = db.Column(db.String(100), nullable=False)  # programming, python, etc.
    display_name = db.Column(db.String(200), nullable=False)

    # Polling configuration
    enabled = db.Column(db.Boolean, default=True, nullable=False)
    poll_interval_minutes = db.Column(db.Integer, default=60, nullable=False)  # How often to poll

    # Status tracking
    last_poll_time = db.Column(db.DateTime, nullable=True)
    last_poll_status = db.Column(db.String(50), nullable=True)  # success, error, etc.
    last_poll_error = db.Column(db.Text, nullable=True)
    posts_collected = db.Column(db.Integer, default=0, nullable=False)

    # Metadata
    created_at = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
    updated_at = db.Column(db.DateTime, nullable=False, default=datetime.utcnow, onupdate=datetime.utcnow)
    created_by = db.Column(db.String(36), db.ForeignKey('users.id'), nullable=True)

    # Unique constraint on platform + source_id
    __table_args__ = (
        db.UniqueConstraint('platform', 'source_id', name='unique_platform_source'),
    )

    def __repr__(self):
        return f'<PollSource {self.platform}:{self.source_id}>'


class PollLog(db.Model):
    """Log of polling activities"""

    __tablename__ = 'poll_logs'

    id = db.Column(db.String(36), primary_key=True, default=lambda: str(uuid.uuid4()))
    source_id = db.Column(db.String(36), db.ForeignKey('poll_sources.id'), nullable=False, index=True)

    started_at = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
    completed_at = db.Column(db.DateTime, nullable=True)
    status = db.Column(db.String(50), nullable=False)  # running, success, error

    posts_found = db.Column(db.Integer, default=0)
    posts_new = db.Column(db.Integer, default=0)
    posts_updated = db.Column(db.Integer, default=0)

    error_message = db.Column(db.Text, nullable=True)

    # Relationship
    source = db.relationship('PollSource', backref=db.backref('logs', lazy='dynamic', order_by='PollLog.started_at.desc()'))

    def __repr__(self):
        return f'<PollLog {self.id} for source {self.source_id}>'