import os
import textwrap

from django.utils.translation import ugettext_lazy as _

from orchestra.apps.orchestration import ServiceController
from orchestra.apps.resources import ServiceMonitor

from . import settings


class SystemUserBackend(ServiceController):
    verbose_name = _("System user")
    model = 'systemusers.SystemUser'
    actions = ('save', 'delete', 'grant_permission')
    
    def save(self, user):
        context = self.get_context(user)
        groups = ','.join(self.get_groups(user))
        context['groups_arg'] = '--groups %s' % groups if groups else ''
        self.append(textwrap.dedent("""
            if [[ $( id %(username)s ) ]]; then
               usermod  %(username)s --password '%(password)s' --shell %(shell)s %(groups_arg)s
            else
               useradd %(username)s --home %(home)s --password '%(password)s' --shell %(shell)s %(groups_arg)s
            fi
            mkdir -p %(home)s
            chown %(username)s.%(username)s %(home)s""" % context
        ))
        for member in settings.SYSTEMUSERS_DEFAULT_GROUP_MEMBERS:
            context['member'] = member
            self.append('usermod -a -G %(username)s %(member)s' % context)
        if not user.is_main:
            self.append('usermod -a -G %(username)s %(mainusername)s' % context)
    
    def delete(self, user):
        context = self.get_context(user)
        self.append("{ sleep 2 && killall -u %(username)s -s KILL; } &" % context)
        self.append("killall -u %(username)s || true" % context)
        self.append("userdel %(username)s || true" % context)
        self.append("groupdel %(username)s || true" % context)
        self.delete_home(context, user)
    
    def grant_permission(self, user):
        context = self.get_context(user)
        # TODO setacl
    
    def delete_home(self, context, user):
        if user.is_main:
            # TODO delete instead of this shit
            context['deleted'] = context['home'].rstrip('/') + '.deleted'
            self.append("mv %(home)s %(deleted)s" % context)
    
    def get_groups(self, user):
        if user.is_main:
            return user.account.systemusers.exclude(username=user.username).values_list('username', flat=True)
        return list(user.groups.values_list('username', flat=True))
    
    def get_context(self, user):
        context = {
            'object_id': user.pk,
            'username': user.username,
            'password': user.password if user.active else '*%s' % user.password,
            'shell': user.shell,
            'mainusername': user.username if user.is_main else user.account.username,
            'home': user.get_home()
        }
        return context


class SystemUserDisk(ServiceMonitor):
    model = 'systemusers.SystemUser'
    resource = ServiceMonitor.DISK
    verbose_name = _('Systemuser disk')
    
    def prepare(self):
        """ slower """
        self.append(textwrap.dedent("""\
            function monitor () {
                { du -bs "$1" || echo 0; } | awk {'print $1'}
            }"""
        ))
    
    def monitor(self, user):
        context = self.get_context(user)
        if user.is_main or os.path.normpath(user.home) == user.get_base_home():
            self.append("echo %(object_id)s $(monitor %(home)s)" % context)
        else:
            # Home appears to be included in other user home
            self.append("echo %(object_id)s 0" % context)
    
    def get_context(self, user):
        return {
            'object_id': user.pk,
            'home': user.home,
        }


class FTPTraffic(ServiceMonitor):
    model = 'systemusers.SystemUser'
    resource = ServiceMonitor.TRAFFIC
    verbose_name = _('Main FTP traffic')
    
    def prepare(self):
        current_date = self.current_date.strftime("%Y-%m-%d %H:%M:%S %Z")
        self.append(textwrap.dedent("""\
            function monitor () {
                OBJECT_ID=$1
                INI_DATE=$2
                USERNAME="$3"
                LOG_FILE="$4"
                grep "UPLOAD\|DOWNLOAD" "${LOG_FILE}" \\
                    | grep " \\[${USERNAME}\\] " \\
                    | awk -v ini="${INI_DATE}" end="$(date '+%%Y%%m%%d%%H%%M%%S' -d '%s')" '
                        BEGIN {
                            sum = 0
                            months["Jan"] = "01"
                            months["Feb"] = "02"
                            months["Mar"] = "03"
                            months["Apr"] = "04"
                            months["May"] = "05"
                            months["Jun"] = "06"
                            months["Jul"] = "07"
                            months["Aug"] = "08"
                            months["Sep"] = "09"
                            months["Oct"] = "10"
                            months["Nov"] = "11"
                            months["Dec"] = "12"
                        } {
                            # log: Fri Jul 11 13:23:17 2014
                            split($4, t, ":")
                            # line_date = year month day hour minute second
                            line_date = $5 months[$2] $3 t[1] t[2] t[3]
                            if ( line_date > ini && line_date < end)
                                split($0, l, "\\", ")
                                split(l[3], b, " ")
                                sum += b[1]
                        } END {
                            print sum
                        }
                    ' | xargs echo ${OBJECT_ID}
            }""" % current_date))
    
    def monitor(self, user):
        context = self.get_context(user)
        self.append(
            'monitor %{object_id} $(date "+%Y%m%d%H%M%S" -d "{last_date}") "{username}" "{log_file}"'.format(**context)
        )
    
    def get_context(self, user):
        return {
            'log_file': '%s{,.1}' % settings.SYSTEMUSERS_FTP_LOG_PATH,
            'last_date': self.get_last_date(user.pk).strftime("%Y-%m-%d %H:%M:%S %Z"),
            'object_id': user.pk,
            'username': user.username,
        }