from datetime import datetime
from app import db
from app.config import Config
import os

class Settings(db.Model):
    """Settings model for system configuration"""
    
    __tablename__ = 'settings'
    
    id = db.Column(db.Integer, primary_key=True)
    timezone = db.Column(db.String(50), default='Europe/Rome', nullable=False)
    currency = db.Column(db.String(3), default='EUR', nullable=False)
    rounding_minutes = db.Column(db.Integer, default=1, nullable=False)
    single_active_timer = db.Column(db.Boolean, default=True, nullable=False)
    allow_self_register = db.Column(db.Boolean, default=True, nullable=False)
    idle_timeout_minutes = db.Column(db.Integer, default=30, nullable=False)
    backup_retention_days = db.Column(db.Integer, default=30, nullable=False)
    backup_time = db.Column(db.String(5), default='02:00', nullable=False)  # HH:MM format
    export_delimiter = db.Column(db.String(1), default=',', nullable=False)
    
    # Company branding for invoices
    company_name = db.Column(db.String(200), default='Your Company Name', nullable=False)
    company_address = db.Column(db.Text, default='Your Company Address', nullable=False)
    company_email = db.Column(db.String(200), default='info@yourcompany.com', nullable=False)
    company_phone = db.Column(db.String(50), default='+1 (555) 123-4567', nullable=False)
    company_website = db.Column(db.String(200), default='www.yourcompany.com', nullable=False)
    company_logo_filename = db.Column(db.String(255), default='', nullable=True)  # Changed from company_logo_path
    company_tax_id = db.Column(db.String(100), default='', nullable=True)
    company_bank_info = db.Column(db.Text, default='', nullable=True)
    
    # PDF template customization
    invoice_pdf_template_html = db.Column(db.Text, default='', nullable=True)
    invoice_pdf_template_css = db.Column(db.Text, default='', nullable=True)
    invoice_pdf_design_json = db.Column(db.Text, default='', nullable=True)  # Konva.js design state
    
    # Invoice defaults
    invoice_prefix = db.Column(db.String(10), default='INV', nullable=False)
    invoice_start_number = db.Column(db.Integer, default=1000, nullable=False)
    invoice_terms = db.Column(db.Text, default='Payment is due within 30 days of invoice date.', nullable=False)
    invoice_notes = db.Column(db.Text, default='Thank you for your business!', nullable=False)
    
    # Privacy and analytics settings
    allow_analytics = db.Column(db.Boolean, default=True, nullable=False)  # Controls system info sharing for analytics
    
    # Email configuration settings (stored in database, takes precedence over environment variables)
    mail_enabled = db.Column(db.Boolean, default=False, nullable=False)  # Enable database-backed email config
    mail_server = db.Column(db.String(255), default='', nullable=True)
    mail_port = db.Column(db.Integer, default=587, nullable=True)
    mail_use_tls = db.Column(db.Boolean, default=True, nullable=True)
    mail_use_ssl = db.Column(db.Boolean, default=False, nullable=True)
    mail_username = db.Column(db.String(255), default='', nullable=True)
    mail_password = db.Column(db.String(255), default='', nullable=True)  # Store encrypted in production
    mail_default_sender = db.Column(db.String(255), default='', nullable=True)
    
    created_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
    updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)
    
    def __init__(self, **kwargs):
        # Set defaults from config
        self.timezone = kwargs.get('timezone', Config.TZ)
        self.currency = kwargs.get('currency', Config.CURRENCY)
        self.rounding_minutes = kwargs.get('rounding_minutes', Config.ROUNDING_MINUTES)
        self.single_active_timer = kwargs.get('single_active_timer', Config.SINGLE_ACTIVE_TIMER)
        self.allow_self_register = kwargs.get('allow_self_register', Config.ALLOW_SELF_REGISTER)
        self.idle_timeout_minutes = kwargs.get('idle_timeout_minutes', Config.IDLE_TIMEOUT_MINUTES)
        self.backup_retention_days = kwargs.get('backup_retention_days', Config.BACKUP_RETENTION_DAYS)
        self.backup_time = kwargs.get('backup_time', Config.BACKUP_TIME)
        self.export_delimiter = kwargs.get('export_delimiter', ',')
        
        # Set company branding defaults
        self.company_name = kwargs.get('company_name', 'Your Company Name')
        self.company_address = kwargs.get('company_address', 'Your Company Address')
        self.company_email = kwargs.get('company_email', 'info@yourcompany.com')
        self.company_phone = kwargs.get('company_phone', '+1 (555) 123-4567')
        self.company_website = kwargs.get('company_website', 'www.yourcompany.com')
        self.company_logo_filename = kwargs.get('company_logo_filename', '')
        self.company_tax_id = kwargs.get('company_tax_id', '')
        self.company_bank_info = kwargs.get('company_bank_info', '')
        
        # PDF template customization
        self.invoice_pdf_template_html = kwargs.get('invoice_pdf_template_html', '')
        self.invoice_pdf_template_css = kwargs.get('invoice_pdf_template_css', '')
        self.invoice_pdf_design_json = kwargs.get('invoice_pdf_design_json', '')
        
        # Set invoice defaults
        self.invoice_prefix = kwargs.get('invoice_prefix', 'INV')
        self.invoice_start_number = kwargs.get('invoice_start_number', 1000)
        self.invoice_terms = kwargs.get('invoice_terms', 'Payment is due within 30 days of invoice date.')
        self.invoice_notes = kwargs.get('invoice_notes', 'Thank you for your business!')
        
        # Email configuration defaults
        self.mail_enabled = kwargs.get('mail_enabled', False)
        self.mail_server = kwargs.get('mail_server', '')
        self.mail_port = kwargs.get('mail_port', 587)
        self.mail_use_tls = kwargs.get('mail_use_tls', True)
        self.mail_use_ssl = kwargs.get('mail_use_ssl', False)
        self.mail_username = kwargs.get('mail_username', '')
        self.mail_password = kwargs.get('mail_password', '')
        self.mail_default_sender = kwargs.get('mail_default_sender', '')
    
    def __repr__(self):
        return f'<Settings {self.id}>'
    
    def get_logo_url(self):
        """Get the full URL for the company logo"""
        if self.company_logo_filename:
            return f'/uploads/logos/{self.company_logo_filename}'
        return None
    
    def get_logo_path(self):
        """Get the full file system path for the company logo"""
        if not self.company_logo_filename:
            return None
            
        try:
            from flask import current_app
            upload_folder = os.path.join(current_app.root_path, 'static', 'uploads', 'logos')
            return os.path.join(upload_folder, self.company_logo_filename)
        except RuntimeError:
            # current_app not available (e.g., during testing or initialization)
            # Fallback to a relative path
            return os.path.join('app', 'static', 'uploads', 'logos', self.company_logo_filename)
    
    def has_logo(self):
        """Check if company has a logo uploaded"""
        if not self.company_logo_filename:
            return False
        
        logo_path = self.get_logo_path()
        return logo_path and os.path.exists(logo_path)
    
    def get_mail_config(self):
        """Get email configuration, preferring database settings over environment variables"""
        if self.mail_enabled and self.mail_server:
            return {
                'MAIL_SERVER': self.mail_server,
                'MAIL_PORT': self.mail_port or 587,
                'MAIL_USE_TLS': self.mail_use_tls if self.mail_use_tls is not None else True,
                'MAIL_USE_SSL': self.mail_use_ssl if self.mail_use_ssl is not None else False,
                'MAIL_USERNAME': self.mail_username or None,
                'MAIL_PASSWORD': self.mail_password or None,
                'MAIL_DEFAULT_SENDER': self.mail_default_sender or 'noreply@timetracker.local',
            }
        return None
    
    def to_dict(self):
        """Convert settings to dictionary for API responses"""
        return {
            'id': self.id,
            'timezone': self.timezone,
            'currency': self.currency,
            'rounding_minutes': self.rounding_minutes,
            'single_active_timer': self.single_active_timer,
            'allow_self_register': self.allow_self_register,
            'idle_timeout_minutes': self.idle_timeout_minutes,
            'backup_retention_days': self.backup_retention_days,
            'backup_time': self.backup_time,
            'export_delimiter': self.export_delimiter,
            'company_name': self.company_name,
            'company_address': self.company_address,
            'company_email': self.company_email,
            'company_phone': self.company_phone,
            'company_website': self.company_website,
            'company_logo_filename': self.company_logo_filename,
            'company_logo_url': self.get_logo_url(),
            'has_logo': self.has_logo(),
            'company_tax_id': self.company_tax_id,
            'company_bank_info': self.company_bank_info,
            'invoice_prefix': self.invoice_prefix,
            'invoice_start_number': self.invoice_start_number,
            'invoice_terms': self.invoice_terms,
            'invoice_notes': self.invoice_notes,
            'invoice_pdf_template_html': self.invoice_pdf_template_html,
            'invoice_pdf_template_css': self.invoice_pdf_template_css,
            'invoice_pdf_design_json': self.invoice_pdf_design_json,
            'allow_analytics': self.allow_analytics,
            'mail_enabled': self.mail_enabled,
            'mail_server': self.mail_server,
            'mail_port': self.mail_port,
            'mail_use_tls': self.mail_use_tls,
            'mail_use_ssl': self.mail_use_ssl,
            'mail_username': self.mail_username,
            'mail_password_set': bool(self.mail_password),  # Don't expose actual password
            'mail_default_sender': self.mail_default_sender,
            'created_at': self.created_at.isoformat() if self.created_at else None,
            'updated_at': self.updated_at.isoformat() if self.updated_at else None
        }
    
    @classmethod
    def get_settings(cls):
        """Get the singleton settings instance, creating it if it doesn't exist"""
        settings = cls.query.first()
        if settings:
            return settings
        
        # Avoid performing session writes during flush/commit phases.
        # When called from default column factories (e.g., created_at=local_now),
        # SQLAlchemy may be in the middle of a flush. Writing here would raise
        # SAWarnings/ResourceClosedError. In that case, return a transient instance
        # with sensible defaults; the persistent row can be created later by
        # initialization code or explicit admin flows.
        try:
            if not getattr(db.session, "_flushing", False):
                settings = cls()
                db.session.add(settings)
                db.session.commit()
                return settings
        except Exception:
            # If anything goes wrong creating the persistent row, rollback and
            # fall back to an in-memory Settings instance.
            try:
                db.session.rollback()
            except Exception:
                # Ignore rollback failures to avoid masking original contexts
                pass
        
        # Fallback: return a non-persisted Settings instance
        return cls()
    
    @classmethod
    def update_settings(cls, **kwargs):
        """Update settings with new values"""
        settings = cls.get_settings()
        
        for key, value in kwargs.items():
            if hasattr(settings, key):
                setattr(settings, key, value)
        
        settings.updated_at = datetime.utcnow()
        db.session.commit()
        return settings