#!/usr/local/bin/python
# Published under the BSDL.

import sys,os,os.path

if len(sys.argv) < 3:
	print "Expecting arguments: jails_home nr_jails"
	sys.exit(1)

metaroot = sys.argv[1]
nrjails = int(sys.argv[2])

def add_dir(root, prefix, dir, type="nullfs", perm="ro"):
    """Appends to per-jail fstab and creates directories. 
    Example arguments: /jails j666 /bin"""
    destdir = "%s/%s%s" % (root, prefix, dir)
    ffstab = file("%s/fstab_%s" % (root, prefix), "a")
    if type == "nullfs":
        ffstab.write("%s\t%s\tnullfs\t%s\t0\t0\n" % (dir, destdir, perm))
    else:
        ffstab.write("%s\t%s\t%s\t%s\t0\t0\n" % ("none", destdir, type, perm))
    ffstab.close()
    if not os.path.exists(destdir):
        os.mkdir(destdir)

def add_distribution(root, prefix):
    """Makes DISTRIBUTION to the prefix"""
    os.system("cd /usr/src && make distrib-dirs DESTDIR=%s/%s >/dev/null && cd -" % (root, prefix))
    os.system("cd /usr/src && make -i distribution DESTDIR=%s/%s >/dev/null && cd -" % (root, prefix))

def write_conf(root, prefix, fname, line):
    """Writes something to destination config file in /etc of the jail"""
    frcd = file("%s/%s/etc/%s" % (root, prefix, fname), "a")
    frcd.write("%s\n" % line)
    frcd.close()

def chpasswd(root, prefix, user, passwd):
    p = os.popen("/usr/sbin/pw -V %s/%s/etc usermod %s -h 0" % (root, prefix, user), "w")
    p.write(passwd)
    p.close()


jails = []

cur_ip = [10, 0, 1, 2]

for x in xrange(nrjails):
    prefix = "j%04d" % x
    root = "%s/%s" % (metaroot, prefix)
    if not os.path.exists(root):
        os.mkdir(root)
    if not os.path.exists("%s/usr" % root):
        os.mkdir("%s/usr" % root)
    if os.path.exists("%s/fstab_%s" % (metaroot, prefix)):
        os.unlink("%s/fstab_%s" % (metaroot, prefix))
    if os.path.exists("%s/etc/rc.conf" % root):
        os.unlink("%s/etc/rc.conf" % root)
    if os.path.exists("%s/etc/ssh/sshd_config" % root):
        os.unlink("%s/etc/ssh/sshd_config" % root)

    add_dir(metaroot, prefix, "/bin")
    add_dir(metaroot, prefix, "/sbin")
    add_dir(metaroot, prefix, "/lib")
    add_dir(metaroot, prefix, "/libexec")
    add_dir(metaroot, prefix, "/usr/bin")
    add_dir(metaroot, prefix, "/usr/sbin")
    add_dir(metaroot, prefix, "/usr/include")
    add_dir(metaroot, prefix, "/usr/lib")
    add_dir(metaroot, prefix, "/usr/libexec")
    add_dir(metaroot, prefix, "/usr/libdata")
    add_dir(metaroot, prefix, "/usr/share")
    add_dir(metaroot, prefix, "/usr/src")
    add_dir(metaroot, prefix, "/usr/ports", "nullfs", "rw")

    add_distribution(metaroot, prefix)

    write_conf(metaroot, prefix, "rc.conf", "sshd_enable='YES'")
    write_conf(metaroot, prefix, "rc.conf", "sendmail_enable='NONE'")
    write_conf(metaroot, prefix, "ssh/sshd_config", "PermitRootLogin yes")

    chpasswd(metaroot, prefix, "root", prefix)

    ip = ".".join([str(x) for x in cur_ip])

    jails.append({ "name" : prefix, "ip" : ip})

    # assume no more than /16
    cur_ip[-1] += 1
    if cur_ip[-1] > 254:
        cur_ip[-2] += 1
        cur_ip[-1] = 2

f = file("rc.conf.jails", "w")
f.write("jail_enable='YES'\n")
f.write("jail_devfs_enable='YES'\n")

f.write("jail_list='%s'\n" % " ".join([j["name"] for j in jails]))
alias_id = 0
for j in jails:
    f.write("\n")
    f.write("jail_%s_rootdir='%s/%s'\n" % (j["name"], metaroot, j["name"]))
    f.write("jail_%s_mount_enable='YES'\n" % j["name"])
    f.write("jail_%s_fstab='%s/fstab_%s'\n" % (j["name"], metaroot, j["name"]))
    f.write("jail_%s_hostname='%s.cosmos'\n" % (j["name"], j["name"]))
    f.write("jail_%s_ip='%s/16'\n" % (j["name"], j["ip"]))
    f.write("jail_%s_interface='%s'\n" % (j["name"], "em0"))
    alias_id += 1

f.close()