#!/usr/bin/env python

from __future__ import print_function
from __future__ import absolute_import
import os
import platform
import sys
import subprocess

if False:
    from typing import Callable, List

TOOLS_DIR = os.path.dirname(__file__)
ROOT_DIR = os.path.dirname(TOOLS_DIR)
sys.path.insert(0, ROOT_DIR)

def run(check_func):
    # type: (Callable) -> None
    '''
    This decorator simply runs functions.  It makes it more
    convenient to add new checks without a big main() function.
    '''
    rc = check_func()
    if not rc:
        sys.exit(1)

def run_command(args):
    # type: (List[str]) -> None
    print(' '.join(args))
    subprocess.check_call(args)

@run
def check_python_version():
    # type: () -> bool
    subprocess.check_call(['/usr/bin/env', 'python', '-V'])
    return True

@run
def pwd():
    # type: () -> bool
    subprocess.check_call('pwd')
    return True

@run
def host_info():
    # type: () -> bool
    print(platform.platform())
    return True

@run
def check_django():
    # type: () -> bool
    try:
        import django
        print('Django version:', django.get_version())
        return True
    except ImportError:
        print('''
            ERROR!
            We cannot import Django, which is usually a
            symptom of not having your Python venv
            set up correctly.

            Make sure your shell does this at init time:

            source /srv/zulip-venv/bin/activate

            Or maybe you forget to run inside your VM?
            ''')
        return False

@run
def provision_version():
    # type: () -> bool
    fn = os.path.join(ROOT_DIR, 'var/provision_version')
    with open(fn) as f:
        version = f.read().strip()
    print('latest version provisioned:', version)
    from version import PROVISION_VERSION
    print('desired version:', PROVISION_VERSION)
    if version != PROVISION_VERSION:
        print('You need to provision!')
        return False
    return True

@run
def node_stuff():
    # type: () -> bool
    print('node version:')
    subprocess.check_call(['node', '--version'])
    return True

@run
def test_models():
    # type: () -> bool
    settings_module = "zproject.settings"
    os.environ['DJANGO_SETTINGS_MODULE'] = settings_module
    import django
    django.setup()
    from zerver.models import UserProfile, Realm
    print('Num realms: ', Realm.objects.count())
    print('Num users: ', UserProfile.objects.count())
    return True

@run
def check_venv():
    # type: () -> bool
    path = os.path.join(ROOT_DIR, 'scripts', 'lib', 'hash_reqs.py')
    cache_dir = '/srv/zulip-venv-cache/'
    for fn in ['py2_dev.txt', 'py3_dev.txt']:
        requirements_file = os.path.join(ROOT_DIR, "requirements", fn)
        output = subprocess.check_output([path, requirements_file], universal_newlines=True)
        sha1sum = output.split()[0]
        print(fn, 'venv sha: ', sha1sum)
        if not os.path.exists(os.path.join(cache_dir, sha1sum)):
            print('Your venv may be improperly installed!')
            return False
    return True

@run
def check_migrations():
    # type: () -> bool
    print()
    rc = subprocess.check_call('./tools/test-migrations')
    return (rc == 0)