from flask_sqlalchemy import SQLAlchemy
from flask_login import UserMixin
from werkzeug.security import generate_password_hash, check_password_hash

db = SQLAlchemy()

class User(db.Model, UserMixin):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(64), unique=True, nullable=False)
    email = db.Column(db.String(120), unique=True, nullable=False)
    password_hash = db.Column(db.String(128))
    is_admin = db.Column(db.Boolean, default=False)
    
    def set_password(self, password):
        self.password_hash = generate_password_hash(password)
        
    def check_password(self, password):
        return check_password_hash(self.password_hash, password)

class NodeImage(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    node_id = db.Column(db.Integer, db.ForeignKey('node.id'), nullable=False)
    image_url = db.Column(db.String(500), nullable=False)
    caption = db.Column(db.String(200), nullable=True)
    display_order = db.Column(db.Integer, default=0)
    
    # Relationship back to the node
    node = db.relationship('Node', backref=db.backref('images', cascade='all, delete-orphan'))

class Node(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    question = db.Column(db.String(500), nullable=False)
    content = db.Column(db.Text, nullable=True)
    is_terminal = db.Column(db.Boolean, default=False)
    
    # Keep single image_url for backward compatibility
    image_url = db.Column(db.String(500), nullable=True)
    youtube_url = db.Column(db.String(500), nullable=True)
    
    # Relationships
    yes_node_id = db.Column(db.Integer, db.ForeignKey('node.id'), nullable=True)
    no_node_id = db.Column(db.Integer, db.ForeignKey('node.id'), nullable=True)
    
    yes_node = db.relationship('Node', foreign_keys=[yes_node_id], remote_side=[id], backref='yes_parent', uselist=False)
    no_node = db.relationship('Node', foreign_keys=[no_node_id], remote_side=[id], backref='no_parent', uselist=False)
    
    @property
    def youtube_embed_url(self):
        """Convert YouTube URL to embed URL"""
        if not self.youtube_url:
            return None
            
        import re
        from urllib.parse import urlparse, parse_qs
        
        # Extract video ID from various YouTube URL formats
        video_id = None
        
        # youtube.com/watch?v=VIDEO_ID format
        if 'youtube.com/watch' in self.youtube_url:
            parsed_url = urlparse(self.youtube_url)
            video_id = parse_qs(parsed_url.query).get('v', [None])[0]
        
        # youtu.be/VIDEO_ID format
        elif 'youtu.be/' in self.youtube_url:
            video_id = self.youtube_url.split('youtu.be/')[1].split('?')[0]
        
        if video_id:
            return f"https://www.youtube.com/embed/{video_id}"
        
        return None

class Product(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(100), nullable=False)
    thumbnail = db.Column(db.String(200))  # URL or file path to the thumbnail image
    description = db.Column(db.Text)  # Add this line for product description
    root_node_id = db.Column(db.Integer, db.ForeignKey('node.id'))
    root_node = db.relationship("Node", foreign_keys=[root_node_id])

class SiteConfig(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    key = db.Column(db.String(64), unique=True, nullable=False)
    value = db.Column(db.String(255), nullable=True)
    description = db.Column(db.String(255), nullable=True)
    
    @classmethod
    def get_setting(cls, key, default=None):
        setting = cls.query.filter_by(key=key).first()
        if setting:
            return setting.value
        return default
    
    @classmethod
    def set_setting(cls, key, value, description=None):
        setting = cls.query.filter_by(key=key).first()
        if setting:
            setting.value = value
            if description:
                setting.description = description
        else:
            setting = cls(key=key, value=value, description=description)
            db.session.add(setting)
        db.session.commit()
        return setting