"""
Document models for the application.
"""

from datetime import datetime
import json
from app.database.db import db

class Document(db.Model):
    """Document model representing a document in the library."""

    __tablename__ = 'documents'

    id = db.Column(db.Integer, primary_key=True)
    title = db.Column(db.String(255), nullable=False)
    description = db.Column(db.Text, nullable=True)
    file_path = db.Column(db.String(255), nullable=True)
    content_type = db.Column(db.String(50), nullable=False)
    status = db.Column(db.String(20), default='pending')  # pending, processing, completed, error
    created_at = db.Column(db.DateTime, default=datetime.utcnow)
    updated_at = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    # Foreign keys
    uploaded_by = db.Column(db.Integer, db.ForeignKey('users.id'), nullable=False)

    # Relationships
    chunks = db.relationship('DocumentChunk', backref='document', lazy='dynamic', cascade='all, delete-orphan')

    def __repr__(self):
        return f'<Document {self.id}: {self.title}>'


class DocumentChunk(db.Model):
    """Model representing a chunk of a document for embedding."""

    __tablename__ = 'document_chunks'

    id = db.Column(db.Integer, primary_key=True)
    content = db.Column(db.Text, nullable=False)
    chunk_index = db.Column(db.Integer, nullable=False)
    embedding_id = db.Column(db.String(100), nullable=True)  # ID in Pinecone
    meta_data = db.Column(db.Text, nullable=True)  # JSON string of metadata
    created_at = db.Column(db.DateTime, default=datetime.utcnow)

    # Foreign keys
    document_id = db.Column(db.Integer, db.ForeignKey('documents.id'), nullable=False)

    def set_metadata(self, metadata_dict):
        """Set metadata as JSON string."""
        self.meta_data = json.dumps(metadata_dict)

    def get_metadata(self):
        """Get metadata as dictionary."""
        if self.meta_data:
            return json.loads(self.meta_data)
        return {}

    def __repr__(self):
        return f'<DocumentChunk {self.id}: doc_id={self.document_id}, index={self.chunk_index}>'