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

HOST_MARKER = "__AUTO_MKNET_MINIO_DEPLOY_DYYycw9Z5c5PvylU"
storage_path = "/tmp/minio-testnet"

# Remove any entry we put in /etc/hosts
def cleanup():
    with open('/etc/hosts', 'r') as fin:
        with open('/etc/hosts', 'w') as fout:
            fout.writelines(filter(lambda line: not HOST_MARKER in line, fin))

def wait(p):
    print("wait", p)
    d = os.path.join(storage_path, p)
    while not os.path.exists(d):
        time.sleep(1)
    #os.unlink(d)
def post(p): 
    print("post", p)
    pathlib.Path(os.path.join(storage_path, p)).touch()

## Create a working directory
me = int(os.environ['ID'])
node_storage_path = os.path.join(storage_path, str(me))
os.makedirs(node_storage_path, exist_ok=True)

## Writing down some info for others
for v in [ 'ZONE', 'HOST', 'IP' ]:
     with open(os.path.join(node_storage_path, v+'.txt'), 'w') as f:
        f.write(os.environ[v])
netsize = int(os.environ['SIZE'])
post("init"+str(me))

## Delete old hosts
if me == 1:
    cleanup()
    with open('/etc/hosts', 'a') as f:
        for i in range(1,netsize+1):
            wait("init"+str(i))
            ip = pathlib.Path(os.path.join(storage_path, str(i), 'IP.txt')).read_text()
            host = pathlib.Path(os.path.join(storage_path, str(i), 'HOST.txt')).read_text()
            f.write(f"{ip} {host} minio{i} # {HOST_MARKER}\n")
    post("hosts")
wait("hosts")

# Adding entries to the host file

# Unsharing the filesystem
data=os.path.join(storage_path, "data")
os.makedirs(data, exist_ok=True)
unshare.unshare(unshare.CLONE_NEWNS)
os.system("mount --make-rprivate /") # see https://stackoverflow.com/a/41580252
os.system("mount -t tmpfs tmpfs "+data)

last = str(netsize)
os.system("minio server --console-address ':9001' --address [" + os.environ['IP'] + "]:9000 http://minio{1.."+last+"}"+data+" > "+node_storage_path + "/minio.log 2>&1")