import os
import subprocess

def run_python_file(working_directory, file_path, args=None):
    try:
        abs_path = os.path.abspath(working_directory)
        new_file_path = os.path.normpath(os.path.join(abs_path, file_path))
        valid_target_file = os.path.commonpath([abs_path, new_file_path]) == abs_path
        if not valid_target_file:
            return f'Error: Cannot execute "{file_path}" as it is outside the permitted working directory'
        if not os.path.isfile(new_file_path):
            return f'Error: "{file_path}" does not exist or is not a regular file'
        if not file_path.endswith(".py"):
            return f'Error: "{file_path}" is not a Python file'
    
        command = ["python", new_file_path]
        if args:
            command.extend(args)
        
        completed_process = subprocess.run(
            command,
            cwd=abs_path,
            capture_output=True,
            text=True,
            timeout=30
        )
        
        output = []
        if completed_process.returncode != 0:
            output.append(f"Process exited with code {completed_process.returncode}")
        if not completed_process.stdout and not completed_process.stderr:
            output.append("No output produced")
        if completed_process.stdout:
            output.append(f"STDOUT: {completed_process.stdout}")
        if completed_process.stderr:
            output.append(f"STDERR: {completed_process.stderr}")
        return "\n".join(output)
    except Exception as e:
        return f"Error: executing Python file: {e}"