"""
Headscale SQLite Database Models for SQLAlchemy
Based on actual schema analysis of Headscale v0.23.0

Generated from: /var/lib/headscale/db.sqlite
Schema Analysis Date: 2025-09-09
"""

from datetime import datetime, timedelta
from typing import Optional, List
import json
from sqlalchemy import (
    Column, Integer, String, DateTime, Boolean, Text, 
    ForeignKey, LargeBinary, Index, UniqueConstraint
)
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import relationship, Session
from sqlalchemy.types import TypeDecorator, TEXT

Base = declarative_base()


class JSONType(TypeDecorator):
    """Custom JSON type for SQLAlchemy that handles JSON serialization"""
    impl = TEXT
    
    def process_bind_param(self, value, dialect):
        if value is not None:
            return json.dumps(value)
        return value
    
    def process_result_value(self, value, dialect):
        if value is not None:
            return json.loads(value)
        return value


class Migration(Base):
    """Migration tracking table"""
    __tablename__ = 'migrations'
    
    id = Column(String, primary_key=True)
    
    def __repr__(self):
        return f"<Migration(id='{self.id}')>"


class User(Base):
    """Headscale Users table
    
    Represents individual users/namespaces in the Headscale network.
    Each user can have multiple nodes (machines) associated with them.
    """
    __tablename__ = 'users'
    __table_args__ = (
        Index('idx_users_deleted_at', 'deleted_at'),
        Index('idx_provider_identifier', 'provider_identifier', 
              postgresql_where="provider_identifier IS NOT NULL"),
        Index('idx_name_provider_identifier', 'name', 'provider_identifier'),
        Index('idx_name_no_provider_identifier', 'name', 
              postgresql_where="provider_identifier IS NULL"),
    )
    
    id = Column(Integer, primary_key=True, autoincrement=True)
    created_at = Column(DateTime)
    updated_at = Column(DateTime)
    deleted_at = Column(DateTime)  # Soft delete
    name = Column(String)  # User identifier (e.g., "myuser")
    display_name = Column(String)  # Human-readable display name
    email = Column(String)  # User email address
    provider_identifier = Column(String)  # External auth provider ID
    provider = Column(String)  # Auth provider name (OIDC, etc.)
    profile_pic_url = Column(String)  # Profile picture URL
    
    # Relationships
    nodes = relationship("Node", back_populates="user", cascade="all, delete-orphan")
    pre_auth_keys = relationship("PreAuthKey", back_populates="user")
    
    def __repr__(self):
        return f"<User(id={self.id}, name='{self.name}', display_name='{self.display_name}')>"
    
    def is_deleted(self) -> bool:
        """Check if user is soft-deleted"""
        return self.deleted_at is not None


class Node(Base):
    """Headscale Nodes (Machines) table
    
    Represents individual devices/machines connected to the Tailnet.
    Each node belongs to a user and has various networking attributes.
    """
    __tablename__ = 'nodes'
    
    id = Column(Integer, primary_key=True, autoincrement=True)
    machine_key = Column(String)  # Machine's public key
    node_key = Column(String)  # Node's network key
    disco_key = Column(String)  # Discovery key for peer-to-peer connections
    endpoints = Column(JSONType)  # List of network endpoints (JSON array)
    host_info = Column(JSONType)  # Detailed host information (JSON object)
    ipv4 = Column(String)  # Assigned IPv4 address (e.g., "100.64.0.1")
    ipv6 = Column(String)  # Assigned IPv6 address
    hostname = Column(String)  # Machine hostname
    given_name = Column(String)  # User-assigned machine name
    user_id = Column(Integer, ForeignKey('users.id', ondelete='CASCADE'))
    register_method = Column(String)  # Registration method (e.g., "authkey")
    forced_tags = Column(JSONType)  # Tags forced on this node (JSON array)
    auth_key_id = Column(Integer, ForeignKey('pre_auth_keys.id'))
    expiry = Column(DateTime)  # Node expiration date
    last_seen = Column(DateTime)  # Last activity timestamp
    approved_routes = Column(JSONType)  # Approved subnet routes (JSON array)
    created_at = Column(DateTime)
    updated_at = Column(DateTime)
    deleted_at = Column(DateTime)  # Soft delete
    
    # Relationships
    user = relationship("User", back_populates="nodes")
    auth_key = relationship("PreAuthKey")
    
    def __repr__(self):
        return f"<Node(id={self.id}, hostname='{self.hostname}', ipv4='{self.ipv4}', user_id={self.user_id})>"
    
    def is_online(self, timeout_minutes: int = 1440) -> bool:  # 24 hours timeout like Tailscale
        """Check if node is considered online based on last_seen"""
        if not self.last_seen:
            return False
        
        # Handle timezone-aware datetime properly
        now = datetime.now()
        last_seen = self.last_seen
        
        # Convert both to naive datetime to avoid timezone issues
        if last_seen.tzinfo is not None:
            last_seen = last_seen.replace(tzinfo=None)
        if now.tzinfo is not None:
            now = now.replace(tzinfo=None)
        
        try:
            time_diff_seconds = (now - last_seen).total_seconds()
            # Consider online if last seen within timeout_minutes
            is_recent = time_diff_seconds < (timeout_minutes * 60)
            return is_recent
        except TypeError as e:
            # Fallback: just check if we have a recent timestamp
            return True
    
    def get_host_info(self) -> dict:
        """Get parsed host information"""
        return self.host_info or {}
    
    def get_endpoints(self) -> List[str]:
        """Get list of network endpoints"""
        return self.endpoints or []
    
    def get_forced_tags(self) -> List[str]:
        """Get list of forced tags"""
        return self.forced_tags or []
    
    def get_approved_routes(self) -> List[str]:
        """Get list of approved routes"""
        return self.approved_routes or []


class PreAuthKey(Base):
    """Pre-authentication keys table
    
    Keys used for automatic node registration without manual approval.
    """
    __tablename__ = 'pre_auth_keys'
    
    id = Column(Integer, primary_key=True, autoincrement=True)
    key = Column(String)  # The actual pre-auth key string
    user_id = Column(Integer, ForeignKey('users.id', ondelete='SET NULL'))
    reusable = Column(Boolean)  # Can be used multiple times
    ephemeral = Column(Boolean, default=False)  # Temporary key
    used = Column(Boolean, default=False)  # Has been used
    tags = Column(JSONType)  # Tags to apply to nodes using this key
    created_at = Column(DateTime)
    expiration = Column(DateTime)  # When the key expires
    
    # Relationships
    user = relationship("User", back_populates="pre_auth_keys")
    
    def __repr__(self):
        return f"<PreAuthKey(id={self.id}, key='{self.key[:8]}...', user_id={self.user_id}, reusable={self.reusable})>"
    
    def is_expired(self) -> bool:
        """Check if the pre-auth key is expired"""
        if not self.expiration:
            return False
        
        now = datetime.now()
        expiration = self.expiration
        
        # Handle timezone-aware datetime
        if expiration.tzinfo is not None and now.tzinfo is None:
            from datetime import timezone
            now = now.replace(tzinfo=timezone.utc)
        elif expiration.tzinfo is not None:
            expiration = expiration.replace(tzinfo=None)
        
        try:
            return now > expiration
        except TypeError:
            return False
    
    def is_valid(self) -> bool:
        """Check if the key is still valid for use"""
        if self.is_expired():
            return False
        if self.used and not self.reusable:
            return False
        return True
    
    def get_tags(self) -> List[str]:
        """Get list of tags for this key"""
        return self.tags or []


class ApiKey(Base):
    """API Keys table
    
    Keys used for API authentication to the Headscale server.
    """
    __tablename__ = 'api_keys'
    __table_args__ = (
        Index('idx_api_keys_prefix', 'prefix', unique=True),
    )
    
    id = Column(Integer, primary_key=True, autoincrement=True)
    prefix = Column(String)  # Key prefix for identification (e.g., "8qRr1IB")
    hash = Column(LargeBinary)  # Hashed key value
    created_at = Column(DateTime)
    expiration = Column(DateTime)  # When the key expires
    last_seen = Column(DateTime)  # Last time key was used
    
    def __repr__(self):
        return f"<ApiKey(id={self.id}, prefix='{self.prefix}', created_at='{self.created_at}')>"
    
    def is_expired(self) -> bool:
        """Check if the API key is expired"""
        if not self.expiration:
            return False
        
        now = datetime.now()
        expiration = self.expiration
        
        # Handle timezone-aware datetime
        if expiration.tzinfo is not None and now.tzinfo is None:
            from datetime import timezone
            now = now.replace(tzinfo=timezone.utc)
        elif expiration.tzinfo is not None:
            expiration = expiration.replace(tzinfo=None)
        
        try:
            return now > expiration
        except TypeError:
            return False


class Policy(Base):
    """ACL Policies table
    
    Stores Access Control List policies in JSON format.
    """
    __tablename__ = 'policies'
    __table_args__ = (
        Index('idx_policies_deleted_at', 'deleted_at'),
    )
    
    id = Column(Integer, primary_key=True, autoincrement=True)
    created_at = Column(DateTime)
    updated_at = Column(DateTime)
    deleted_at = Column(DateTime)  # Soft delete
    data = Column(Text)  # JSON policy data
    
    def __repr__(self):
        return f"<Policy(id={self.id}, created_at='{self.created_at}')>"
    
    def get_policy_data(self) -> dict:
        """Parse and return policy data as dictionary"""
        try:
            return json.loads(self.data) if self.data else {}
        except json.JSONDecodeError:
            return {}


# ==========================================
# Extended Models for FARMQ Customization
# ==========================================

# ==========================================
# Extended Models for FARMQ Customization - DEPRECATED
# ==========================================
# 
# 주의: 이 모델들은 Headscale과 외래키 충돌을 일으키므로 더 이상 사용하지 않습니다.
# 대신 farmq_models.py의 독립적인 모델들을 사용하세요.
# 
# 마이그레이션 가이드:
# - PharmacyInfo -> farmq_models.PharmacyInfo 
# - MachineSpecs -> farmq_models.MachineProfile
# - MonitoringData -> farmq_models.MonitoringMetrics
#
# 이 클래스들은 하위 호환성을 위해 유지되지만 실제 테이블은 생성되지 않습니다.


# ==========================================
# Database Helper Functions
# ==========================================

def create_all_tables(engine):
    """Create all tables in the database"""
    Base.metadata.create_all(engine)


def get_active_nodes(session: Session) -> List[Node]:
    """Get all non-deleted nodes"""
    return session.query(Node).filter(Node.deleted_at.is_(None)).all()


def get_online_nodes(session: Session, timeout_minutes: int = 5) -> List[Node]:
    """Get nodes that are currently online"""
    cutoff_time = datetime.now() - timedelta(minutes=timeout_minutes)
    return session.query(Node).filter(
        Node.deleted_at.is_(None),
        Node.last_seen > cutoff_time
    ).all()


def get_user_with_pharmacy_info(session: Session, user_name: str):
    """Get user with associated pharmacy information"""
    return session.query(User).join(PharmacyInfo).filter(User.name == user_name).first()


def get_node_with_specs_and_monitoring(session: Session, node_id: int):
    """Get node with hardware specs and latest monitoring data"""
    return session.query(Node)\
        .outerjoin(MachineSpecs)\
        .outerjoin(MonitoringData)\
        .filter(Node.id == node_id)\
        .first()


# ==========================================
# Usage Example
# ==========================================

if __name__ == "__main__":
    from sqlalchemy import create_engine
    from sqlalchemy.orm import sessionmaker
    
    # SQLite connection to Headscale database
    DATABASE_URL = "sqlite:///data/db.sqlite"
    engine = create_engine(DATABASE_URL)
    SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
    
    # Create extended tables (if needed)
    create_all_tables(engine)
    
    # Example usage
    session = SessionLocal()
    try:
        # Get all users
        users = session.query(User).all()
        print("=== Users ===")
        for user in users:
            print(f"  {user}")
        
        # Get all nodes
        nodes = session.query(Node).all()
        print("\n=== Nodes ===")
        for node in nodes:
            print(f"  {node}")
            print(f"    Online: {node.is_online()}")
            print(f"    Host Info: {node.get_host_info().get('Hostname', 'Unknown')}")
        
        # Get all API keys
        api_keys = session.query(ApiKey).all()
        print("\n=== API Keys ===")
        for key in api_keys:
            print(f"  {key}")
            print(f"    Expired: {key.is_expired()}")
            
    finally:
        session.close()