📝 Commit Details:

backend/database/__init__.py

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+# Database package initialization file
+# Makes the directory a proper Python package 

backend/database/db_manager.py

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+import os
+import logging
+from typing import List, Optional, Any
+from datetime import datetime
+
+from sqlalchemy import create_engine, func
+from sqlalchemy.orm import sessionmaker, Session, joinedload
+
+from models import User, Printer, Job, Stats, Base
+from config.settings import DATABASE_PATH, ensure_database_directory
+
+logger = logging.getLogger(__name__)
+
+class DatabaseManager:
+    """Database manager class to handle database operations."""
+    
+    def __init__(self):
+        """Initialize the database manager."""
+        ensure_database_directory()
+        self.engine = create_engine(f"sqlite:///{DATABASE_PATH}")
+        self.Session = sessionmaker(bind=self.engine)
+    
+    def get_session(self) -> Session:
+        """Get a new database session.
+        
+        Returns:
+            Session: A new SQLAlchemy session.
+        """
+        return self.Session()
+    
+    def test_connection(self) -> bool:
+        """Test the database connection.
+        
+        Returns:
+            bool: True if the connection is successful, False otherwise.
+        """
+        try:
+            session = self.get_session()
+            session.execute("SELECT 1")
+            session.close()
+            return True
+        except Exception as e:
+            logger.error(f"Database connection test failed: {str(e)}")
+            return False
+    
+    def get_all_jobs(self) -> List[Job]:
+        """Get all jobs with eager loading of relationships.
+        
+        Returns:
+            List[Job]: A list of all jobs.
+        """
+        session = self.get_session()
+        try:
+            jobs = session.query(Job).options(
+                joinedload(Job.user),
+                joinedload(Job.printer)
+            ).all()
+            return jobs
+        finally:
+            session.close()
+    
+    def get_jobs_by_status(self, status: str) -> List[Job]:
+        """Get jobs by status with eager loading of relationships.
+        
+        Args:
+            status: The job status to filter by.
+            
+        Returns:
+            List[Job]: A list of jobs with the specified status.
+        """
+        session = self.get_session()
+        try:
+            jobs = session.query(Job).options(
+                joinedload(Job.user),
+                joinedload(Job.printer)
+            ).filter(Job.status == status).all()
+            return jobs
+        finally:
+            session.close()
+    
+    def get_job_by_id(self, job_id: int) -> Optional[Job]:
+        """Get a job by ID with eager loading of relationships.
+        
+        Args:
+            job_id: The job ID to find.
+            
+        Returns:
+            Optional[Job]: The job if found, None otherwise.
+        """
+        session = self.get_session()
+        try:
+            job = session.query(Job).options(
+                joinedload(Job.user),
+                joinedload(Job.printer)
+            ).filter(Job.id == job_id).first()
+            return job
+        finally:
+            session.close()
+    
+    def get_available_printers(self) -> List[Printer]:
+        """Get all available printers.
+        
+        Returns:
+            List[Printer]: A list of available printers.
+        """
+        session = self.get_session()
+        try:
+            printers = session.query(Printer).filter(
+                Printer.active == True,
+                Printer.status != "busy"
+            ).all()
+            return printers
+        finally:
+            session.close()
+    
+    def get_jobs_since(self, since_date: datetime) -> List[Job]:
+        """Get jobs created since a specific date.
+        
+        Args:
+            since_date: The date to filter jobs from.
+            
+        Returns:
+            List[Job]: A list of jobs created since the specified date.
+        """
+        session = self.get_session()
+        try:
+            jobs = session.query(Job).options(
+                joinedload(Job.user),
+                joinedload(Job.printer)
+            ).filter(Job.created_at >= since_date).all()
+            return jobs
+        finally:
+            session.close()