import subprocess
import threading
import time
from pr.multiplexer import create_multiplexer, get_multiplexer, close_multiplexer, get_all_multiplexer_states

def start_interactive_session(command, session_name=None, process_type='generic'):
    """
    Start an interactive session in a dedicated multiplexer.

    Args:
        command: The command to run (list or string)
        session_name: Optional name for the session
        process_type: Type of process (ssh, vim, apt, etc.)

    Returns:
        session_name: The name of the created session
    """
    name, mux = create_multiplexer(session_name)
    mux.update_metadata('process_type', process_type)

    # Start the process
    if isinstance(command, str):
        command = command.split()

    try:
        process = subprocess.Popen(
            command,
            stdin=subprocess.PIPE,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE,
            text=True,
            bufsize=1
        )

        mux.process = process
        mux.update_metadata('pid', process.pid)

        # Set process type and handler
        detected_type = detect_process_type(command)
        mux.set_process_type(detected_type)

        # Start output readers
        stdout_thread = threading.Thread(target=_read_output, args=(process.stdout, mux.write_stdout), daemon=True)
        stderr_thread = threading.Thread(target=_read_output, args=(process.stderr, mux.write_stderr), daemon=True)

        stdout_thread.start()
        stderr_thread.start()

        mux.stdout_thread = stdout_thread
        mux.stderr_thread = stderr_thread

        return name
    except Exception as e:
        close_multiplexer(name)
        raise e

def _read_output(stream, write_func):
    """Read from a stream and write to multiplexer buffer."""
    try:
        for line in iter(stream.readline, ''):
            if line:
                write_func(line.rstrip('\n'))
    except Exception as e:
        print(f"Error reading output: {e}")

def send_input_to_session(session_name, input_data):
    """
    Send input to an interactive session.

    Args:
        session_name: Name of the session
        input_data: Input string to send
    """
    mux = get_multiplexer(session_name)
    if not mux:
        raise ValueError(f"Session {session_name} not found")

    if not hasattr(mux, 'process') or mux.process.poll() is not None:
        raise ValueError(f"Session {session_name} is not active")

    try:
        mux.process.stdin.write(input_data + '\n')
        mux.process.stdin.flush()
    except Exception as e:
        raise RuntimeError(f"Failed to send input to session {session_name}: {e}")

def read_session_output(session_name, lines=None):
    """
    Read output from a session.

    Args:
        session_name: Name of the session
        lines: Number of recent lines to return (None for all)

    Returns:
        dict: {'stdout': str, 'stderr': str}
    """
    mux = get_multiplexer(session_name)
    if not mux:
        raise ValueError(f"Session {session_name} not found")

    output = mux.get_all_output()
    if lines is not None:
        # Return last N lines
        stdout_lines = output['stdout'].split('\n')[-lines:] if output['stdout'] else []
        stderr_lines = output['stderr'].split('\n')[-lines:] if output['stderr'] else []
        output = {
            'stdout': '\n'.join(stdout_lines),
            'stderr': '\n'.join(stderr_lines)
        }
    return output

def list_active_sessions():
    """
    List all active interactive sessions.

    Returns:
        dict: Session states
    """
    return get_all_multiplexer_states()

def get_session_status(session_name):
    """
    Get detailed status of a session.

    Args:
        session_name: Name of the session

    Returns:
        dict: Session metadata and status
    """
    mux = get_multiplexer(session_name)
    if not mux:
        return None

    status = mux.get_metadata()
    status['is_active'] = hasattr(mux, 'process') and mux.process.poll() is None
    if status['is_active']:
        status['pid'] = mux.process.pid
    status['output_summary'] = {
        'stdout_lines': len(mux.stdout_buffer),
        'stderr_lines': len(mux.stderr_buffer)
    }
    return status

def close_interactive_session(session_name):
    """
    Close an interactive session.
    """
    try:
        mux = get_multiplexer(session_name)
        if mux:
            mux.process.kill()
        close_multiplexer(session_name)
        return {"status": "success"}
    except Exception as e:
        return {"status": "error", "error": str(e)}