with open('app/utils/tasks.py', 'r', encoding='utf-8') as f:
    text = f.read()

import re
old_block = re.search(r'tmp_def_path = None.*?db\.session\.remove\(\)', text, re.DOTALL)

new_block = """from app.utils.slice_engines import get_slicer_engine
        
        try:
            # Optionally fetch the preferred engine from db conf or just default to cura
            # For now default to cura or whichever is passed via kwargs if implemented later
            conf_engine = SystemConfig.query.filter_by(key='slicer_engine').first()
            engine_name = conf_engine.value if conf_engine and conf_engine.value else "cura"
            db.session.remove()
            
            slicer = get_slicer_engine(engine_name)
            
            success, err_msg = slicer.slice(
                app=app,
                stl_filepath=stl_filepath,
                gcode_filepath=gcode_filepath,
                quality_preset=quality_preset,
                infill_density=infill_density,
                support_enable=support_enable,
                support_pattern=support_pattern
            )
            
            # Re-fetch print_file and update status
            print_file = PrintFile.query.get(file_id)
            if not print_file:
                return

            if success:
                print_file.status = 'sliced'
            else:
                print_file.status = 'failed'
                app.logger.error(f"Slicing Task Failed: {err_msg}")
                
        except Exception as e:
            print_file = PrintFile.query.get(file_id)
            if print_file:
                print_file.status = 'failed'
            app.logger.error(f"Subprocess Exception: {e}")
            
        finally:
            if delete_stl and os.path.exists(stl_filepath):
                try:
                    os.remove(stl_filepath)
                except Exception as e:
                    app.logger.error(f"Failed to delete temp STL {stl_filepath}: {e}")
                    
            db.session.commit()
            db.session.remove()"""

if old_block:
    res = text.replace(old_block.group(0), new_block)
    with open('app/utils/tasks.py', 'w', encoding='utf-8') as f:
        f.write(res)
    print("Patched successfully")
else:
    print("Pattern not found!")