#!/usr/bin/env python3

import http.client
import json
import socket
import os
import subprocess

DOCKER_SOCKET_PATHS = [
    '/var/run/docker.sock',                 # Default path,
    '$HOME/.colima/default/docker.sock',    # Colima
]
 

_docker_socket = None
def find_docker_socket():
    """Iterate through common paths to find the Docker Unix socket."""
    global _docker_socket
    if _docker_socket:
        return _docker_socket
    for path in DOCKER_SOCKET_PATHS:
        expanded_path = os.path.expandvars(path)
        if os.path.exists(expanded_path):
            _docker_socket = expanded_path
            return _docker_socket
    raise FileNotFoundError("Docker Unix socket not found")


def shorten_volume_name(volume_name):
    """Shorten volume names to a maximum of 30 characters."""
    if len(volume_name) > 30:
        return volume_name[:27] + '...'
    return volume_name


def get_volume_size(mountpoint):
    """Get the size of the volume using 'du -hs'."""
    try:
        # Run 'du -hs' command to get the size of the directory
        result = subprocess.run(['du', '-hs', mountpoint], stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True)

        if result.returncode != 0:
            # Handle errors if 'du' command fails
            #print(f"Error running 'du -hs' on {mountpoint}: {result.stderr.strip()}")
            return "---"

        # The output will be something like '1.4G /path/to/volume'
        size_str = result.stdout.split()[0]  # Get the size part
        return size_str  # Return size as printed by 'du -hs'

    except Exception as e:
        #print(f"Exception while getting volume size: {e}")
        return "---"


def docker_api_request(endpoint):
    """Make a request to the Docker REST API using the Unix socket."""
    socket_path = find_docker_socket()
    sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
    sock.connect(socket_path)
    
    conn = http.client.HTTPConnection("localhost")
    conn.sock = sock  # Use the Unix socket
    
    conn.request("GET", endpoint)
    response = conn.getresponse()
    
    if response.status != 200:
        print(f"Error: {response.status} - {response.reason}")
        return None
    
    data = response.read()
    conn.close()
    return json.loads(data)

# Print the header
print(f"{'Docker Volume Name':<30} | {'Size':<10} | {'Container'}")
print('-' * 60)

# Get the list of volumes
volumes_data = docker_api_request("/volumes")

if volumes_data:
    volumes = volumes_data.get('Volumes', [])
    volumes.sort(key=lambda volume: volume['Name'])

    for volume in volumes:
        volume_name = volume['Name']
        mountpoint = volume['Mountpoint']
        volume_size = get_volume_size(mountpoint)

        # Get containers using the volume
        containers_data = docker_api_request(f"/containers/json?all=1&filters={{\"volume\":[\"{volume_name}\"]}}")
        containers = containers_data if containers_data else []
        
        # Check if any container is using the volume
        if not containers:
            container_names = '---'
        else:
            container_names = ', '.join(container['Names'][0].lstrip('/') for container in containers)
        
        # Shorten the volume name if necessary
        short_volume_name = shorten_volume_name(volume_name)

        # Print the volume information
        print(f"{short_volume_name:<30} | {volume_size:<10} | {container_names}")