#!/bin/python3
import yaml, os, sys, time, pathlib, unshare, socket, shutil

STORAGE_PATH = os.path.join(os.getcwd(), '.minio-testnet')
#STORAGE_PATH = os.path.join('/mnt/windows', '.minio-testnet')
MINIO_PATH = '/srv'
HOSTS_PATH = os.path.join(STORAGE_PATH, 'hosts.txt')
UNIX_SOCK = os.path.join(STORAGE_PATH, 'deploy.sock')
DATA_PATH = lambda nid: os.path.join(STORAGE_PATH, 'data'+str(nid))

def main():
    unshare.unshare(unshare.CLONE_NEWNS)
    os.system("mount --make-rprivate /") # see https://stackoverflow.com/a/41580252
    if int(os.environ['ID']) == 1: leader()
    else: follower()

def leader():
    shutil.rmtree(STORAGE_PATH, ignore_errors=True)
    os.makedirs(STORAGE_PATH)
    os.makedirs(MINIO_PATH, exist_ok=True)
    print(STORAGE_PATH)

    sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
    sock.bind(UNIX_SOCK)
    sock.listen()

    n_serv = n_servers()
    fl = [ co for co, addr in [ sock.accept() for i in range(n_serv - 1) ]]

    ips = [ co.makefile().readline().strip() for co in fl ] + [ os.environ['IP'] ]
    print(f"ips: {ips}")
    gen_hosts(ips)
    [ co.send(f"{n_serv}\n".encode()) for co in fl ]

    mount_hosts()
    mount_disk()

    run_minio(n_serv)

def follower():
    co = None
    while True:
        time.sleep(3)
        try:
            sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
            sock.connect(UNIX_SOCK)
            co = sock.makefile()
            break
        except Exception as err:
            print('conn failed, wait,', err)
    sock.send(f"{os.environ['IP']}\n".encode())
    n_serv = int(co.readline())

    mount_hosts()
    mount_disk()

    run_minio(n_serv)

def run_minio(count):
    cmd = f"minio server --console-address ':9001' --address [{os.environ['IP']}]:9000"
    for i in range(1,count+1):
        cmd += f" http://minio{i}:9000{DATA_PATH(i)}"
    cmd += f" > {os.path.join(STORAGE_PATH, 'minio'+os.environ['ID']+'.log')} 2>&1"
    os.system(cmd)
    print("done: ", cmd)

def gen_hosts(ips):
    with open(HOSTS_PATH, 'w') as f:
        for idx,ip in enumerate(ips):
            f.write(f"{ip} minio{idx+1}\n")

def n_servers():
    with open('.current_state.yml', 'r') as f:
        netw = yaml.safe_load(f)
        n_servers = len(netw['servers'])
        return n_servers

def mount_disk():
    data_path = DATA_PATH(os.environ['ID'])
    os.makedirs(data_path)

def mount_hosts():
    os.system(f"mount --bind {HOSTS_PATH} /etc/hosts")

__name__ == '__main__' and main()