# -*- 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/>.
"""
Glances swap memory plugin
"""

# Import system libs
# Check for PSUtil already done in the glances_core script
from psutil import swap_memory

# from ..plugins.glances_plugin import GlancesPlugin
from glances.plugins.glances_plugin import GlancesPlugin


class Plugin(GlancesPlugin):
    """
    Glances's swap memory Plugin

    stats is a dict
    """

    def __init__(self):
        GlancesPlugin.__init__(self)

        # We want to display the stat in the curse interface
        self.display_curse = True
        # Set the message position
        # It is NOT the curse position but the Glances column/line
        # Enter -1 to right align
        self.column_curse = 3
        # Enter -1 to diplay bottom
        self.line_curse = 1

    def update(self):
        """
        Update MEM (SWAP) stats
        """

        # Grab SWAP using the PSUtil swap_memory method
        sm_stats = swap_memory()

        # Get all the swap stats (copy/paste of the PsUtil documentation)
        # total: total swap memory in bytes
        # used: used swap memory in bytes
        # free: free swap memory in bytes
        # percent: the percentage usage
        # sin: the number of bytes the system has swapped in from disk (cumulative)
        # sout: the number of bytes the system has swapped out from disk (cumulative)
        swap_stats = {}
        for swap in ['total', 'used', 'free', 'percent',
                     'sin', 'sout']:
            if (hasattr(sm_stats, swap)):
                swap_stats[swap] = getattr(sm_stats, swap)

        # Set the global variable to the new stats
        self.stats = swap_stats

        return self.stats

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

        # Only process if stats exist...
        if (self.stats == {}):
            return ret

        # Build the string message
        # Header
        msg = "{0:7} ".format(_("SWAP"))
        ret.append(self.curse_add_line(msg, "TITLE"))
        # Percent memory usage
        msg = "{0:>5}%".format(format(self.stats['percent'] / 100, '.1'))
        ret.append(self.curse_add_line(msg))
        # New line
        ret.append(self.curse_new_line())
        # Total memory usage
        msg = "{0:8}".format(_("total:"))
        ret.append(self.curse_add_line(msg))
        msg = "{0:>6}".format(self.auto_unit(self.stats['total']))
        ret.append(self.curse_add_line(msg))
        # New line
        ret.append(self.curse_new_line())
        # Used memory usage
        msg = "{0:8}".format(_("used:"))
        ret.append(self.curse_add_line(msg))
        msg = "{0:>6}".format(self.auto_unit(self.stats['used']))
        ret.append(self.curse_add_line(
            msg, self.get_alert_log(self.stats['used'], 
            max=self.stats['total'])))
        # New line
        ret.append(self.curse_new_line())
        # Free memory usage
        msg = "{0:8}".format(_("free:"))
        ret.append(self.curse_add_line(msg))
        msg = "{0:>6}".format(self.auto_unit(self.stats['free']))
        ret.append(self.curse_add_line(msg))

        return ret