import os
import subprocess
import secrets
import tempfile
from pathlib import Path


class WGInterface:
    def __init__(self, config_path: str, iface_name: str):
        self.config_path = config_path
        self.iface_name = iface_name
        self.up = False

    def bring_up(self, timeout=30):
        subprocess.run(['sudo', 'wg-quick', 'up', self.config_path],
                       check=True, timeout=timeout, capture_output=True, text=True)
        self.up = True

    def bring_down(self):
        if self.up:
            subprocess.run(['sudo', 'wg-quick', 'down', self.config_path],
                           check=False, timeout=15, capture_output=True)
            self.up = False

    def is_connected(self, server_ip='10.0.0.1', timeout=5) -> bool:
        result = subprocess.run(
            ['ping', '-c', '1', '-W', str(timeout), server_ip],
            capture_output=True, timeout=timeout + 2
        )
        return result.returncode == 0


def build_wg_config(private_key: str, peer_ip: str, server_pubkey: str,
                     server_endpoint: str, server_port: int = 51820,
                     allowed_ips: str = '10.0.0.0/24',
                     dns: str = '10.0.0.1') -> str:
    return (
        f"[Interface]\n"
        f"PrivateKey = {private_key}\n"
        f"Address = {peer_ip}/32\n"
        f"DNS = {dns}\n\n"
        f"[Peer]\n"
        f"PublicKey = {server_pubkey}\n"
        f"Endpoint = {server_endpoint}:{server_port}\n"
        f"AllowedIPs = {allowed_ips}\n"
        f"PersistentKeepalive = 25\n"
    )


def cleanup_stale_e2e_interfaces():
    """Remove any leftover pic-e2e-* interfaces from previous failed runs."""
    result = subprocess.run(['ip', 'link', 'show'], capture_output=True, text=True)
    for line in result.stdout.splitlines():
        if 'pic-e2e-' in line:
            iface = line.split(':')[1].strip().split('@')[0]
            subprocess.run(['sudo', 'ip', 'link', 'delete', iface], capture_output=True)