# -*- 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/>.

"""Manage logs."""

# Import system libs
import time
from datetime import datetime

# Import Glances libs
from glances.core.glances_globals import glances_processes


class GlancesLogs(object):

    """This class manages logs inside the Glances software.

    Logs is a list of list (stored in the self.logs_list var)
    item_state = "OK|CAREFUL|WARNING|CRITICAL"
    item_type = "CPU*|LOAD|MEM|MON"
    item_value = value

    Item is defined by:
      ["begin",
       "end",
       "WARNING|CRITICAL",
       "CPU|LOAD|MEM",
       MAX, AVG, MIN, SUM, COUNT,
       [top3 process list],
       "Processes description"]
    """

    def __init__(self):
        """Init the logs class."""
        # Maximum size of the logs list
        self.logs_max = 10

        # Init the logs list
        self.logs_list = []

    def get(self):
        """Return the raw logs list."""
        return self.logs_list

    def len(self):
        """Return the number of item in the logs list."""
        return self.logs_list.__len__()

    def __itemexist__(self, item_type):
        """Return the item position, if it exists.

        An item exist in the list if:
        * end is < 0
        * item_type is matching
        Return -1 if the item is not found.
        """
        for i in range(self.len()):
            if self.logs_list[i][1] < 0 and self.logs_list[i][3] == item_type:
                return i
        return -1

    def set_process_sort(self, item_type):
        """Define the process auto sort key from the alert type."""
        # Process sort depending on alert type
        if item_type.startswith("MEM"):
            # Sort TOP process by memory_percent
            process_auto_by = 'memory_percent'
        elif item_type.startswith("CPU_IOWAIT"):
            # Sort TOP process by io_counters (only for Linux OS)
            process_auto_by = 'io_counters'
        else:
            # Default sort is...
            process_auto_by = 'cpu_percent'

        glances_processes.setsortkey(process_auto_by)

        return process_auto_by

    def reset_process_sort(self):
        """Reset the process_auto_by variable."""
        # Default sort is...
        process_auto_by = 'cpu_percent'

        glances_processes.setsortkey(process_auto_by)

        return process_auto_by

    def add(self, item_state, item_type, item_value, proc_list=[], proc_desc=""):
        """Add a new item to the logs list.

        If 'item' is a 'new one', add the new item at the beginning of the logs
        list.
        If 'item' is not a 'new one', update the existing item.
        """
        # Add or update the log
        item_index = self.__itemexist__(item_type)
        if item_index < 0:
            # Item did not exist, add if WARNING or CRITICAL
            if item_state == "WARNING" or item_state == "CRITICAL":
                # Define the automatic process sort key
                self.set_process_sort(item_type)

                # Create the new log item
                # Time is stored in Epoch format
                # Epoch -> DMYHMS = datetime.fromtimestamp(epoch)
                item = []
                # START DATE
                item.append(time.mktime(datetime.now().timetuple()))
                item.append(-1)               # END DATE
                item.append(item_state)       # STATE: WARNING|CRITICAL
                item.append(item_type)        # TYPE: CPU, LOAD, MEM...
                item.append(item_value)       # MAX
                item.append(item_value)       # AVG
                item.append(item_value)       # MIN
                item.append(item_value)       # SUM
                item.append(1)                # COUNT
                # Process list is sorted automaticaly
                # Overwrite the user choise
                # topprocess = sorted(proc_list, key=lambda process: process[process_auto_by],
                #                     reverse=True)
                # item.append(topprocess[0:3])  # TOP 3 PROCESS LIST
                item.append([])               # TOP 3 PROCESS LIST
                item.append(proc_desc)        # MONITORED PROCESSES DESC

                # Add the item to the list
                self.logs_list.insert(0, item)
                if self.len() > self.logs_max:
                    self.logs_list.pop()
        else:
            # Item exist, update
            if item_state == "OK" or item_state == "CAREFUL":
                # Reset the automatic process sort key
                self.reset_process_sort()

                # Close the item
                self.logs_list[item_index][1] = time.mktime(
                    datetime.now().timetuple())
            else:
                # Update the item
                # State
                if item_state == "CRITICAL":
                    self.logs_list[item_index][2] = item_state
                # Value
                if item_value > self.logs_list[item_index][4]:
                    # MAX
                    self.logs_list[item_index][4] = item_value
                elif item_value < self.logs_list[item_index][6]:
                    # MIN
                    self.logs_list[item_index][6] = item_value
                # AVG
                self.logs_list[item_index][7] += item_value
                self.logs_list[item_index][8] += 1
                self.logs_list[item_index][5] = (self.logs_list[item_index][7] /
                                                 self.logs_list[item_index][8])
                # TOP PROCESS LIST
                # # Process list is sorted automaticaly
                # # Overwrite the user choise
                # topprocess = sorted(proc_list, key=lambda process: process[process_auto_by],
                #                     reverse=True)
                # # TOP PROCESS LIST
                # self.logs_list[item_index][9] = topprocess[0:3]
                self.logs_list[item_index][9] = []
                # MONITORED PROCESSES DESC
                self.logs_list[item_index][10] = proc_desc

        return self.len()

    def clean(self, critical=False):
        """Clean the logs list by deleting finished items.

        By default, only delete WARNING message
        If critical = True, also delete CRITICAL message
        """
        # Create a new clean list
        clean_logs_list = []
        while (self.len() > 0):
            item = self.logs_list.pop()
            if item[1] < 0 or (not critical and item[2].startswith("CRITICAL")):
                clean_logs_list.insert(0, item)
        # The list is now the clean one
        self.logs_list = clean_logs_list
        return self.len()
