models.py

# models.py
from flask_sqlalchemy import SQLAlchemy
from flask_login import UserMixin
from datetime import datetime
from werkzeug.security import generate_password_hash, check_password_hash

db = SQLAlchemy()

class User(UserMixin, db.Model):
    """User model for authentication and profile management."""
    __tablename__ = 'users'
    
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True, nullable=False)
    email = db.Column(db.String(120), unique=True, nullable=False)
    password_hash = db.Column(db.String(255), nullable=False)
    full_name = db.Column(db.String(100), nullable=False)
    student_id = db.Column(db.String(20), unique=True, nullable=True)
    department = db.Column(db.String(100), nullable=True)
    year_of_study = db.Column(db.String(20), nullable=True)
    phone_number = db.Column(db.String(20), nullable=True)
    is_active = db.Column(db.Boolean, default=True)
    is_admin = db.Column(db.Boolean, default=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    last_login = db.Column(db.DateTime, nullable=True)
    
    # Relationships
    chat_sessions = db.relationship('ChatSession', backref='user', lazy=True, cascade='all, delete-orphan')
    device_specs = db.relationship('DeviceSpec', backref='user', lazy=True, cascade='all, delete-orphan')
    support_tickets = db.relationship('SupportTicket', backref='user', lazy=True, cascade='all, delete-orphan')
    
    def set_password(self, password):
        """Hash and set the user's password."""
        self.password_hash = generate_password_hash(password)
    
    def check_password(self, password):
        """Check if the provided password matches the user's password."""
        return check_password_hash(self.password_hash, password)
    
    def __repr__(self):
        return f'<User {self.username}>'

class DeviceSpec(db.Model):
    """Device specification model to store user's device information."""
    __tablename__ = 'device_specs'
    
    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False)
    device_name = db.Column(db.String(100), nullable=False)
    device_type = db.Column(db.String(50), nullable=False)  # laptop, desktop, mobile, etc.
    operating_system = db.Column(db.String(100), nullable=False)
    processor = db.Column(db.String(100), nullable=True)
    ram = db.Column(db.String(50), nullable=True)
    storage = db.Column(db.String(100), nullable=True)
    graphics_card = db.Column(db.String(100), nullable=True)
    network_adapter = db.Column(db.String(100), nullable=True)
    other_specs = db.Column(db.Text, nullable=True)
    is_primary = db.Column(db.Boolean, default=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
    
    def __repr__(self):
        return f'<DeviceSpec {self.device_name} - {self.user.username}>'

class ChatSession(db.Model):
    """Chat session model to store conversation history."""
    __tablename__ = 'chat_sessions'
    
    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=True)  # Nullable for anonymous users
    session_id = db.Column(db.String(100), nullable=False, unique=True)
    title = db.Column(db.String(200), nullable=True)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
    is_resolved = db.Column(db.Boolean, default=False)
    escalated_to_support = db.Column(db.Boolean, default=False)
    
    # Relationships
    messages = db.relationship('ChatMessage', backref='session', lazy=True, cascade='all, delete-orphan')
    
    def __repr__(self):
        return f'<ChatSession {self.session_id}>'

class ChatMessage(db.Model):
    """Individual chat message model."""
    __tablename__ = 'chat_messages'
    
    id = db.Column(db.Integer, primary_key=True)
    session_id = db.Column(db.Integer, db.ForeignKey('chat_sessions.id'), nullable=False)
    message_type = db.Column(db.String(20), nullable=False)  # 'user' or 'bot'
    content = db.Column(db.Text, nullable=False)
    timestamp = db.Column(db.DateTime, default=datetime.utcnow)
    confidence_score = db.Column(db.Float, nullable=True)  # For bot responses
    faq_matched = db.Column(db.Boolean, default=False)
    
    def __repr__(self):
        return f'<ChatMessage {self.message_type}: {self.content[:50]}...>'

class SupportTicket(db.Model):
    """Support ticket model for escalated issues."""
    __tablename__ = 'support_tickets'
    
    id = db.Column(db.Integer, primary_key=True)
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False)
    chat_session_id = db.Column(db.Integer, db.ForeignKey('chat_sessions.id'), nullable=True)
    ticket_number = db.Column(db.String(20), unique=True, nullable=False)
    title = db.Column(db.String(200), nullable=False)
    description = db.Column(db.Text, nullable=False)
    category = db.Column(db.String(100), nullable=False)  # hardware, software, network, etc.
    priority = db.Column(db.String(20), default='medium')  # low, medium, high, urgent
    status = db.Column(db.String(20), default='open')  # open, in_progress, resolved, closed
    assigned_to = db.Column(db.String(100), nullable=True)  # Technical staff member
    device_info = db.Column(db.Text, nullable=True)  # JSON string of device specs
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
    resolved_at = db.Column(db.DateTime, nullable=True)
    resolution_notes = db.Column(db.Text, nullable=True)
    
    def generate_ticket_number(self):
        """Generate a unique ticket number."""
        import uuid
        return f"TKT-{datetime.utcnow().strftime('%Y%m%d')}-{str(uuid.uuid4())[:8].upper()}"
    
    def __repr__(self):
        return f'<SupportTicket {self.ticket_number}: {self.title}>'

class AdminUser(db.Model):
    """Admin/Technical staff model for managing support tickets."""
    __tablename__ = 'admin_users'
    
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True, nullable=False)
    email = db.Column(db.String(120), unique=True, nullable=False)
    password_hash = db.Column(db.String(255), nullable=False)
    full_name = db.Column(db.String(100), nullable=False)
    role = db.Column(db.String(50), default='technician')  # technician, supervisor, admin
    department = db.Column(db.String(100), nullable=True)
    is_active = db.Column(db.Boolean, default=True)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    last_login = db.Column(db.DateTime, nullable=True)
    
    def set_password(self, password):
        """Hash and set the admin's password."""
        self.password_hash = generate_password_hash(password)
    
    def check_password(self, password):
        """Check if the provided password matches the admin's password."""
        return check_password_hash(self.password_hash, password)
    
    def __repr__(self):
        return f'<AdminUser {self.username}>'