# kpov_util should be imported by add_assignment.py

# TODO: finish this!
instructions = {
    'si': '''\
<p>
Postavite dva navidezna računalnika: <em>SimpleArbiterDhcpRdate</em> in <em>rdateClient</em>.

<p>
Nastavite čas na <em>rdateClient</em> tako, da kot rdate strežnik uporabite <em>SimpleArbiterDhcpRdate</em>.

<p>
Na <em>rdateClient</em> ustvarite uporabnika <code>test</code> z geslom <code>test</code>. V domačem imeniku uporabnika <code>test</code> ustvarite program z imenom <code>{{PROGRAM_FILENAME}}</code>. Program naj prebere štiri bajte podatkov s standardnega vhoda in jih pretvori v predznačeno celo število, pri čemer naj uporablja zapis z debelim koncem (angl. <em lang="en">big endian</em>). Število naj program izpiše na standardni izhod v obliki niza.
''',
    'en': '''\
<p>
Set up two virtual machines: <em>SimpleArbiterDhcpRdate</em> and <em>rdateClient</em>.

<p>
Set the time on <em>rdateClient</em> using rdate with <em>SimpleArbiterDhcpRdate</em> as
the server.

<p>
On <em>rdateClient</em> create a user with the username <code>test</code> and password <code>test</code>. Then, write a program called <code>{{PROGRAM_FILENAME}}</code> and put it in user <code>test</code>’s home directory. The program should read four bytes of data from standard input, convert them into a signed integer using big endian byte ordering and output the resulting integer (as a string) to standard output.
''',
}

computers = {
    'rdateClient': {
        'disks': [
            {   'name': 'student-rdate',
            },
        ],
        'network_interfaces': [{'network': 'net1'}],
        'flavor': 'm1.tiny',
        'config_drive': False

    },
    'SimpleArbiter': {
        'disks': [
            {   'name': 'simpleArbiterDhcpGWRdate',
            },
        ],
        'network_interfaces': [{'network': 'net1'}, {'network': 'test-net'}],
        'flavor': 'm1.tiny',
        'config_drive': False
    }
}

networks = { 'net1': {'public': False}, 'test-net': {'public': True} }

# Tu sem dolocil parametre
params_meta = {
    'RDATE_OFFSET':{'descriptions': {'si': 'Napaka v času pri rdate', 'en': 'Timekeeping error for rdate'}, 'w': False, 'public': False, 'type': 'integer', 'generated': True},
    'PROGRAM_FILENAME':{'descriptions': {'si': 'Ime programa', 'en': 'program filename'}, 'w': False, 'public': True, 'type': 'integer', 'generated': True},
    'IP_RDATECLIENT':{'descriptions': {'si': 'IP rdateClient', "en": "rdateClient's IP"}, 'w': True, 'public': True, 'type': 'IP', 'generated': False},
}

def task(IP_RDATECLIENT, PROGRAM_FILENAME):
    import collections
    import base64
    import random
    import struct
    import pexpect

    r = random.Random(PROGRAM_FILENAME)
    results = collections.defaultdict(str)
    tests = []
    for i in range(10):
        data = struct.pack("!I", r.randint(0, 2**32))
        results['in_'+str(i)] = data_ascii = base64.encodestring(data)
        tests += [('out_'+str(i), 'echo "{}" | base64 -d | ~/{}'.format(data_ascii.decode().strip(), PROGRAM_FILENAME))]
    tests += [('date', 'date -u +"%s"')]

    results.update(
        kpov_util.ssh_test(IP_RDATECLIENT, 'test', 'test', tests))
    results['ldate'] = pexpect.run('date -u +"%s"')

    return results

#Dolocil sem tri parametre in sicer jih lahko vidite v prams_meta,
#zato prosim da jih upostevate v naslednih nalogah.
    
def gen_params(user_id, params_meta):
    import socket
    import struct
    import datetime
    params = dict()
    r = random.Random(user_id)
    params['PROGRAM_FILENAME'] = kpov_util.fname_gen(r, False)
    params['RDATE_OFFSET'] = str(r.randint(-2**24, 2**24))
    return params

def task_check(results, params):
    import random
    import struct
    import base64

    r = random.Random(params['PROGRAM_FILENAME'])
    score = 0.0
    hints = []
    for i in range(10):
        data = base64.decodestring(results['in_' + str(i)])
        x = struct.pack("!I", r.randint(0, 2**32))
        if data != x:
            hints += ["data: " + str((data,)) + " != " + str((x,))]
            break
        res = results['out_' + str(i)]
        if str(struct.unpack("!i", data)[0]) == res.strip():
            score += 0.5
        else:
            hints += ["wrong convert"]

    if abs(int(results['ldate']) + \
        int(params['RDATE_OFFSET']) - int(results['date'])) < 3:
        score += 5
    else:
        hints += ["wrong offset"]
    return score, hints

def prepare_disks(templates, task_params, global_params):
    d = templates['simpleArbiterDhcpGWRdate']
    s1 = """service "time_tcp" {{
    enabled yes;
    protocol tcp;
    port "time";
    user "nobody";
    exec "/usr/local/bin/kpovrdate {RDATE_OFFSET}";
    server "/usr/sbin/tcpd";
    wait no;
}}
""".format(**task_params)
    d.write('/etc/rlinetd.d/time', s1)
    s2 = """#!/usr/bin/python

import struct
import time
import sys

offset = int(sys.argv[1])
t = time.time() + offset # used to have + 2208988800
sys.stdout.write(struct.pack("!I", int(t)))
"""
    d.write('/usr/local/bin/kpovrdate', s2)
    d.chmod(0o775, '/usr/local/bin/kpovrdate')
    write_default_config(templates['simpleArbiterDhcpGWRdate'], global_params)