# SPDX-License-Identifier: AGPL-3.0-or-later

# TODO:
# - check if everything is filled in (computers, params, preparation)
# - improve scoring
# - test
# - switch to a real SSH/SFTP client to properly handle filenames

instructions = {
    'si': '''\
<p>
Postavite dva navidezna računalnika - <em>arbiter</em> in <em>student</em>. Drugi mrežni vmesnik na <em>arbiterju</em> in edini vmesnik na <em>studentu</em> naj bosta povezana v isto lokalno omrežje.

<p>
Na računalnik <em>student</em> se prijavite z uporabniškim imenom <code>student</code> in geslom <code>vaje</code>.

<p>
Obstoječi datoteko <code>{{P_c}}</code> v programskem jeziku C prevedite v program z imenom <code>{{P_executable}}</code>. Izvorna koda je namenoma pokvarjena tako, da so vanjo vrinjeni nepotrebni znaki. Pred prevajanjem jo morate popraviti.

<p>
Napišite skripto <code>{{P_script}}</code>, ki požene <code>{{P_executable}}</code> z argumentom

<pre><code>"{{arg_c}}"</code></pre>

<p>
 in

<ul>
<li>mu na standardni vhod zapiše vrednost okoljske spremenljivke <code>{{env_c}}</code>;
<li>v datoteko <code>{{out_stderr_c}}</code> zapiše napake (<em>stderr</em>); in
<li>v datoteko <code>{{out_stdout_c}}</code> zapiše tiste vrstice na standardnem izhodu (<em>stdout</em>), ki vsebujejo niz <code>XYZZY</code>.
</ul>

<p>
Poskrbite, da se bo dalo skripto pognati neposredno, torej z ukazom <code>./{{P_script}}</code>. Vse datoteke naj so v domačem imeniku uporabnika <code>student</code>, ki naj bo tudi njihov lastnik.
''',
    'en': '''\
<p>
Set up two virtual machines - <em>arbiter</em> and <em>student</em>. Connect <em>arbiter’s</em> second network interface and <em>student’s</em> first interface to the same local network.

<p>Log in to <em>student</em> as the user <code>student</code> with password <code>vaje</code>.

<p>Compile the existing C file <code>{{P_c}}</code> into a program named <code>{{P_executable}}</code>. The source code was intentionally corrupted by inserting extraneous characters. Before compiling you have to fix it.

<p>
Write a script called <code>{{P_script}}</code> that runs <code>{{P_executable}}</code> with the argument

<pre><code>"{{arg_c}}"</code></pre>

and

<ul>
<li>pipes the value of the environment variable <code>{{env_c}}</code> into <code>{{P_executable}}</code>’s standard input;
<li>redirects its <code>stderr</code> into a file called <code>{{out_stderr_c}}</code>; and
<li>saves each line from the standard output that contains the string <code>XYZZY</code> into <code>{{out_stdout_c}}</code>.
</ul>

<p>
Ensure that the script can be run directly, ie. <code>./{{P_script}}</code>. All files should be owned by <code>student</code> and placed in that user’s home directory.
''',
}

computers = {
    'arbiter': {
        'disks': [{'name': 'dhcp-gw'}],
        'flavor': 'm1.tiny',
        'network_interfaces': [{'network': 'test-net'}, {'network': 'net1'}],
        'config_drive': True,
        'userdata': {'string': "#!/bin/bash\nsed -i '/cloud/d' /etc/fstab\npoweroff &\n"}
    },
    'student': {
        'disks': [{ 'name': 'console-big'}],
        'flavor': 'm1.tiny',
        'network_interfaces': [{'network': 'net1'}],
        'config_drive': True,
        'userdata': {'string': "#!/bin/bash\nsed -i '/cloud/d' /etc/fstab\npoweroff &\n"}
    }
}

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

params_meta = {
    'student_IP': {
        'descriptions': { 'si': 'IP naslov računalnika student', 'en': 'IP address of student',
        }, 'w': True, 'public': True, 'type': 'IP', 'generated': False,
    },
    'P_c': {
        'descriptions': { 'si': 'Datoteka s programom v C', 'en': 'Filename of the program in C',
        }, 'w': False, 'public': True, 'type': 'filename', 'generated': True,
    },
    'P_executable': { 'descriptions': { 'si': 'Ime prevedenega programa v C', 'en': 'Filename of the compiled C program'
        }, 'w': False, 'public': True, 'type': 'filename', 'generated': True,
    },
    'arg_c': {
        'descriptions': { 'si': 'Vrednost argumenta', 'en': 'Argument value',
        }, 'w': False, 'public': True, 'type': 'short_text', 'generated': True,
    },
    'env_c': {
        'descriptions': { 'si': 'Ime okoljske spremenljivke', 'en': 'The name of the environment environment',
        }, 'w': False, 'public': True, 'type': 'short_text', 'generated': True,
    },
    'out_stderr_c': {
        'descriptions': { 'si': 'Datoteka z napakami', 'en': 'File to store errors',
        }, 'w': False, 'public': True, 'type': 'filename', 'generated': True,
    },
    'P_script': {
        'descriptions': { 'si': 'Ime skripte', 'en': 'Filename of the script',
        }, 'w': False, 'public': True, 'type': 'filename', 'generated': True,
    },
    'out_stdout_c': {
        'descriptions': { 'si': 'Datoteka z izhodom', 'en': 'File to store the output',
        }, 'w': False, 'public': True, 'type': 'filename', 'generated': True,
    },
    'param_gen_seed': {
        'descriptions': { 'si': 'Nakljucno seme', 'en': 'Random seed',
        }, 'w': False, 'public': True, 'type': None, 'generated': True,
    },
    'c_destroy_gen_seed': {
        'descriptions': { 'si': 'Nakljucno seme za kvarjenje kode v C', 'en': 'Random seed for destroying the C code',
        }, 'w': False, 'public': False, 'type': None, 'generated': True,
    }

}

def task(student_IP,
        P_c, P_executable, arg_c, env_c, out_stderr_c, out_stdout_c, P_script,
        param_gen_seed):
    import random

    r = random.Random(int(param_gen_seed))
    env_val = "".join([r.choice('ABCDEFGHJKLMNPRSTUVZ012345') for i in range(11)])
    arg_val = "".join([r.choice('ABCDEFGHJKLMNPRSTUVZ012345') for i in range(13)])
    stdin_val = "".join([r.choice('ABCDEFGHJKLMNPRSTUVZ012345') for i in range(17)])

    return kpov_util.ssh_test(student_IP, 'student', 'vaje', (
        ('script_ls', 'ls -l ./{}'.format(P_script)),
        ('executable_ls', 'ls -l ./{}'.format(P_executable)),
        ('script_run', 'export {}={}; ./{}'.format(env_c, env_val, P_script)),
        ('script_stderr', 'cat {}'.format(out_stderr_c)),
        ('script_stdout', 'cat {}'.format(out_stdout_c)),
        ('prog_stdout', 'echo "{}" | ./{} "{}" 2> /dev/null'.format(stdin_val, P_executable, arg_val)),
        ('prog_stderr', 'echo "{}" | ./{} "{}" > /dev/null'.format(stdin_val, P_executable, arg_val)),
    ))

def gen_params(user_id, params_meta):
    import random
    r = random.Random(user_id+'evil cornholio')
    params = kpov_util.default_gen(user_id, params_meta)
    params['env_c'] = "".join([r.choice('ABCDEFGHIJKLMNPRSTUVZ') for i in range(5)])
    params['P_c'] = "".join([r.choice('abcdefghijklmnoprst') for i in range(5)]) + ".c"
    params['param_gen_seed'] = str(r.randint(0, 2**24))
    params['c_destroy_gen_seed'] = str(r.randint(0, 2**24))
    return params

def task_check(results, params):
    def test_out_gen(arg, env):
        s_out = ""
        s_err = ""
        for i in range(30):
            s = '{}{}\n'.format(
                ('XYZZY' if i%5 == 0 else ''),
                (env if i%2 == 0 else arg))
            if i%3 == 0:
                s_err += s
            else:
                s_out += s
        return (s_out.strip(), s_err.strip(), len(env))

    score = 0
    hints = []
    if results['ssh'] is not True:
        hints += ['ssh failed: ' + results['ssh']]
        return score, hints

    r = random.Random(int(params['param_gen_seed']))
    env_val = "".join([r.choice('ABCDEFGHJKLMNPRSTUVZ012345') for i in range(11)])
    arg_val = "".join([r.choice('ABCDEFGHJKLMNPRSTUVZ012345') for i in range(13)])
    stdin_val = "".join([r.choice('ABCDEFGHJKLMNPRSTUVZ012345') for i in range(17)])
    expected_script_stdout, expected_script_stderr, rval = test_out_gen(
        params['arg_c'], env_val)
    if expected_script_stderr != results['script_stderr']:
        hints += ['wrong script stderr']
    else:
        score += 2
    split_stdout = expected_script_stdout.split('\n')
    expected_script_stdout = '\n'.join([ i for i in split_stdout if i.find('XYZZY') >= 0])
    if expected_script_stdout != results['script_stdout']:
        hints += ['wrong script stdout']
    else:
        score += 2

    expected_prog_stdout, expected_prog_stderr, rval = test_out_gen(arg_val, stdin_val)
    if expected_prog_stderr != results['prog_stderr']:
        hints += ['wrong program stderr']
    else:
        score += 2
    if expected_prog_stdout != results['prog_stdout']:
        hints += ['wrong program stdout']
    else:
        score += 2
    if results['script_ls'].find('-r') < 0:
        hints += ['script not found']
    else:
        score += 1
    if results['executable_ls'].find('xr') < 0:
        hints += ['C executable not found']
    else:
        score += 1
    return score, hints

def prepare_disks(templates, task_params, global_params):
    c_source = '''#include<stdio.h>
#include<stdlib.h>
#include<string.h>

/* Odstranite vse crke Q, W, R in program se bo prevedel. */
/* Remove all letters Q, W, R and the program will compile. */

int main(int argc, char **argv){
    unsigned char *arg = argv[1];
    unsigned char env[255];
    scanf("%s", env);
    size_t env_len = strlen(env);

    for (int i = 0; i < 30; i++) {
        fprintf(i%3 == 0 ? stderr : stdout, "%s%s\\n",
                i%5 == 0 ? "XYZZY" : "",
                i%2 == 0 ? env : arg);
    }
    return env_len;
}
'''

    import random
    d = templates['console-big']
    r = random.Random(task_params['c_destroy_gen_seed'])
    destroyed_c_source = c_source[:110]
    for c in c_source[110:]:
        i = r.randint(0, 5) 
        if i == 1:
            destroyed_c_source += 'QW'
        if i == 2:
            destroyed_c_source += 'RW'
        if i == 3:
            destroyed_c_source += 'QR'
        destroyed_c_source += c

    path_c = '/home/student/{}'.format(task_params['P_c'])
    d.write(path_c, destroyed_c_source)
    d.chown(1000, 1000, path_c)

    write_default_config(templates['dhcp-gw'], global_params)