# -*- coding: utf-8 -*-
#
# This file is part of Glances.
#
# Copyright (C) 2014 Nicolargo <nicolas@nicolargo.com>
#
# Glances is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Glances is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.

"""Per-CPU plugin."""

import psutil

from glances.plugins.glances_plugin import GlancesPlugin


class Plugin(GlancesPlugin):

    """Glances' per-CPU plugin.

    stats is a list
    """

    def __init__(self, args=None):
        """Init the plugin."""
        GlancesPlugin.__init__(self, args=args)

        # We want to display the stat in the curse interface
        self.display_curse = True

        # Init stats
        self.reset()
        self.percputime_total_new = []
        self.percputime_new = []

    def reset(self):
        """Reset/init the stats."""
        self.stats = []

    def update(self):
        """Update per-CPU stats using the input method."""
        # Reset stats
        self.reset()

        if self.get_input() == 'local':
            # Update stats using the standard system lib

            # Grab CPU using the PSUtil cpu_times method
            # Per-CPU
            percputime = psutil.cpu_times(percpu=True)
            percputime_total = []
            for i in range(len(percputime)):
                percputime_total.append(percputime[i].user +
                                        percputime[i].system +
                                        percputime[i].idle)

            # Only available on some OS
            for i in range(len(percputime)):
                if hasattr(percputime[i], 'nice'):
                    percputime_total[i] += percputime[i].nice
            for i in range(len(percputime)):
                if hasattr(percputime[i], 'iowait'):
                    percputime_total[i] += percputime[i].iowait
            for i in range(len(percputime)):
                if hasattr(percputime[i], 'irq'):
                    percputime_total[i] += percputime[i].irq
            for i in range(len(percputime)):
                if hasattr(percputime[i], 'softirq'):
                    percputime_total[i] += percputime[i].softirq
            for i in range(len(percputime)):
                if hasattr(percputime[i], 'steal'):
                    percputime_total[i] += percputime[i].steal
            if not hasattr(self, 'percputime_old'):
                self.percputime_old = percputime
                self.percputime_total_old = percputime_total
            else:
                self.percputime_new = percputime
                self.percputime_total_new = percputime_total
                perpercent = []
                try:
                    for i in range(len(self.percputime_new)):
                        perpercent.append(100 / (self.percputime_total_new[i] -
                                                 self.percputime_total_old[i]))
                        cpu = {'user': (self.percputime_new[i].user -
                                        self.percputime_old[i].user) * perpercent[i],
                               'system': (self.percputime_new[i].system -
                                          self.percputime_old[i].system) * perpercent[i],
                               'idle': (self.percputime_new[i].idle -
                                        self.percputime_old[i].idle) * perpercent[i]}
                        if hasattr(self.percputime_new[i], 'nice'):
                            cpu['nice'] = (self.percputime_new[i].nice -
                                           self.percputime_old[i].nice) * perpercent[i]
                        if hasattr(self.percputime_new[i], 'iowait'):
                            cpu['iowait'] = (self.percputime_new[i].iowait -
                                             self.percputime_old[i].iowait) * perpercent[i]
                        if hasattr(self.percputime_new[i], 'irq'):
                            cpu['irq'] = (self.percputime_new[i].irq -
                                          self.percputime_old[i].irq) * perpercent[i]
                        if hasattr(self.percputime_new[i], 'softirq'):
                            cpu['softirq'] = (self.percputime_new[i].softirq -
                                              self.percputime_old[i].softirq) * perpercent[i]
                        if hasattr(self.percputime_new[i], 'steal'):
                            cpu['steal'] = (self.percputime_new[i].steal -
                                            self.percputime_old[i].steal) * perpercent[i]
                        self.stats.append(cpu)
                    self.percputime_old = self.percputime_new
                    self.percputime_total_old = self.percputime_total_new
                except Exception:
                    self.reset()

        else:
            # Update stats using SNMP
            pass

        return self.stats

    def msg_curse(self, args=None):
        """Return the dict to display in the curse interface."""
        # Init the return message
        ret = []

        # No per CPU stat ? Exit...
        if self.stats == []:
            msg = _("PER CPU not available")
            ret.append(self.curse_add_line(msg, "TITLE"))
            return ret

        # Build the string message
        # Header
        msg = '{0:8}'.format(_("PER CPU"))
        ret.append(self.curse_add_line(msg, "TITLE"))

        # Total CPU usage
        for cpu in self.stats:
            msg = ' {0:>6.1%}'.format((100 - cpu['idle']) / 100)
            ret.append(self.curse_add_line(msg))

        # User CPU
        if 'user' in self.stats[0]:
            # New line
            ret.append(self.curse_new_line())
            msg = '{0:8}'.format(_("user:"))
            ret.append(self.curse_add_line(msg))
            for cpu in self.stats:
                msg = ' {0:>6.1%}'.format(cpu['user'] / 100)
                ret.append(self.curse_add_line(msg, self.get_alert(cpu['user'], header="user")))

        # System CPU
        if 'user' in self.stats[0]:
            # New line
            ret.append(self.curse_new_line())
            msg = '{0:8}'.format(_("system:"))
            ret.append(self.curse_add_line(msg))
            for cpu in self.stats:
                msg = ' {0:>6.1%}'.format(cpu['system'] / 100)
                ret.append(self.curse_add_line(msg, self.get_alert(cpu['system'], header="system")))

        # Idle CPU
        if 'user' in self.stats[0]:
            # New line
            ret.append(self.curse_new_line())
            msg = '{0:8}'.format(_("idle:"))
            ret.append(self.curse_add_line(msg))
            for cpu in self.stats:
                msg = ' {0:>6.1%}'.format(cpu['idle'] / 100)
                ret.append(self.curse_add_line(msg))

        # Return the message with decoration
        return ret