from app import db
from flask_login import UserMixin
from datetime import datetime
import json

class User(db.Model, UserMixin):
    __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(128), nullable=False)
    is_admin = db.Column(db.Boolean, default=False)
    totp_secret = db.Column(db.String(32), nullable=True)
    two_factor_enabled = db.Column(db.Boolean, default=False)
    backup_codes = db.Column(db.Text, nullable=True)  # JSON array of hashed backup codes
    language = db.Column(db.String(5), default='en')
    currency = db.Column(db.String(3), default='USD')
    avatar = db.Column(db.String(255), default='icons/avatars/avatar-1.svg')
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    
    expenses = db.relationship('Expense', backref='user', lazy='dynamic', cascade='all, delete-orphan')
    categories = db.relationship('Category', backref='user', lazy='dynamic', cascade='all, delete-orphan')
    documents = db.relationship('Document', backref='user', lazy='dynamic', cascade='all, delete-orphan')
    
    def __repr__(self):
        return f'<User {self.username}>'


class Category(db.Model):
    __tablename__ = 'categories'
    
    id = db.Column(db.Integer, primary_key=True)
    name = db.Column(db.String(50), nullable=False)
    color = db.Column(db.String(7), default='#2b8cee')
    icon = db.Column(db.String(50), default='category')
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False)
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    
    expenses = db.relationship('Expense', backref='category', lazy='dynamic')
    
    def __repr__(self):
        return f'<Category {self.name}>'
    
    def to_dict(self):
        return {
            'id': self.id,
            'name': self.name,
            'color': self.color,
            'icon': self.icon,
            'created_at': self.created_at.isoformat()
        }


class Expense(db.Model):
    __tablename__ = 'expenses'
    
    id = db.Column(db.Integer, primary_key=True)
    amount = db.Column(db.Float, nullable=False)
    currency = db.Column(db.String(3), default='USD')
    description = db.Column(db.String(200), nullable=False)
    category_id = db.Column(db.Integer, db.ForeignKey('categories.id'), nullable=False)
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False)
    tags = db.Column(db.Text, default='[]')  # JSON array of tags
    receipt_path = db.Column(db.String(255), nullable=True)
    date = db.Column(db.DateTime, default=datetime.utcnow)
    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'<Expense {self.description} - {self.amount} {self.currency}>'
    
    def get_tags(self):
        try:
            return json.loads(self.tags)
        except:
            return []
    
    def set_tags(self, tags_list):
        self.tags = json.dumps(tags_list)
    
    def to_dict(self):
        return {
            'id': self.id,
            'amount': self.amount,
            'currency': self.currency,
            'description': self.description,
            'category_id': self.category_id,
            'category_name': self.category.name if self.category else None,
            'category_color': self.category.color if self.category else None,
            'tags': self.get_tags(),
            'receipt_path': self.receipt_path,
            'date': self.date.isoformat(),
            'created_at': self.created_at.isoformat()
        }


class Document(db.Model):
    """
    Model for storing user documents (bank statements, receipts, invoices, etc.)
    Security: All queries filtered by user_id to ensure users only see their own documents
    """
    __tablename__ = 'documents'
    
    id = db.Column(db.Integer, primary_key=True)
    filename = db.Column(db.String(255), nullable=False)
    original_filename = db.Column(db.String(255), nullable=False)
    file_path = db.Column(db.String(500), nullable=False)
    file_size = db.Column(db.Integer, nullable=False)  # in bytes
    file_type = db.Column(db.String(50), nullable=False)  # PDF, CSV, XLSX, etc.
    mime_type = db.Column(db.String(100), nullable=False)
    document_category = db.Column(db.String(100), nullable=True)  # Bank Statement, Invoice, Receipt, Contract, etc.
    status = db.Column(db.String(50), default='uploaded')  # uploaded, processing, analyzed, error
    user_id = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=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'<Document {self.filename} - {self.user_id}>'
    
    def to_dict(self):
        return {
            'id': self.id,
            'filename': self.original_filename,
            'file_size': self.file_size,
            'file_type': self.file_type,
            'document_category': self.document_category,
            'status': self.status,
            'created_at': self.created_at.isoformat(),
            'updated_at': self.updated_at.isoformat()
        }