# Contributors Listed Below - COPYRIGHT 2016
# [+] International Business Machines Corp.
#
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
# implied. See the License for the specific language governing
# permissions and limitations under the License.

import os
import subprocess
import dbus
import dbus.service
from obmc.dbuslib.bindings import DbusProperties


## Abstract class, must subclass
class SensorValue(DbusProperties):
    IFACE_NAME = 'org.openbmc.SensorValue'

    def __init__(self, bus, name):
        self.Set(SensorValue.IFACE_NAME, 'units', "")
        self.Set(SensorValue.IFACE_NAME, 'error', False)

    @dbus.service.method(
        IFACE_NAME, in_signature='v', out_signature='')
    def setValue(self, value):
        self.Set(SensorValue.IFACE_NAME, 'value', value)

    @dbus.service.method(
        IFACE_NAME, in_signature='', out_signature='v')
    def getValue(self):
        return self.Get(SensorValue.IFACE_NAME, 'value')


class SensorThresholds(DbusProperties):
    IFACE_NAME = 'org.openbmc.SensorThresholds'

    def __init__(self, bus, name):
        self.Set(
            SensorThresholds.IFACE_NAME,
            'thresholds_enabled',
            False)
        self.Set(
            SensorThresholds.IFACE_NAME,
            'emergency_enabled',
            False)
        self.Set(
            SensorThresholds.IFACE_NAME,
            'warning_upper',
            0)
        self.Set(
            SensorThresholds.IFACE_NAME,
            'warning_lower',
            0)
        self.Set(
            SensorThresholds.IFACE_NAME,
            'critical_upper',
            0)
        self.Set(
            SensorThresholds.IFACE_NAME,
            'critical_lower',
            0)
        self.Set(
            SensorThresholds.IFACE_NAME,
            'critical_lower',
            0)
        self.Set(
            SensorThresholds.IFACE_NAME,
            'threshold_state',
            "NORMAL")
        self.Set(
            SensorThresholds.IFACE_NAME,
            'worst_threshold_state',
            "NORMAL")

    @dbus.service.method(
        IFACE_NAME, in_signature='', out_signature='')
    def resetThresholdState(self):
        self.Set(
            SensorThresholds.IFACE_NAME,
            'worst_threshold_state',
            "NORMAL")

    def check_thresholds(self, value):
        iface = SensorThresholds.IFACE_NAME
        if (self.Get(iface, 'thresholds_enabled') is False):
            return False
        rtn = False
        current_state = "NORMAL"
        if (value >= self.properties[iface]['critical_upper']):
            current_state = "CRITICAL"
            rtn = True
        elif (value <= self.properties[iface]['critical_lower']):
            current_state = "CRITICAL"
            rtn = True
        elif (value >= self.properties[iface]['warning_upper']):
            current_state = "WARNING"
            rtn = True
        elif (value <= self.properties[iface]['warning_lower']):
            current_state = "WARNING"
            rtn = True

        if self.Get(iface, 'threshold_state') != current_state and \
                current_state == "CRITICAL" and \
                self.Get(iface, 'emergency_enabled') is True:
            message = type(self).__name__ + \
                ' SensorThresholds.check_thresholds(): trigger emergency' + \
                ' signal, sensor value: ' + str(value)
            self.Emergency(message)

        self.Set(iface, 'threshold_state', current_state)
        worst = self.properties[iface]['worst_threshold_state']
        if (current_state == "CRITICAL" or
           (current_state == "WARNING" and worst != "CRITICAL")):
            self.Set(iface, 'worst_threshold_state', current_state)

        return rtn

    @dbus.service.signal(IFACE_NAME, signature='s')
    def Emergency(self, message):
        pass


class VirtualSensor(SensorValue):
    def __init__(self, bus, name):
        DbusProperties.__init__(self)
        SensorValue.__init__(self, bus, name)
        dbus.service.Object.__init__(self, bus, name)


class HwmonSensor(SensorValue, SensorThresholds):
    IFACE_NAME = 'org.openbmc.HwmonSensor'

    def __init__(self, bus, name):
        DbusProperties.__init__(self)
        SensorValue.__init__(self, bus, name)
        SensorThresholds.__init__(self, bus, name)
        self.Set(HwmonSensor.IFACE_NAME, 'scale', 1)
        self.Set(HwmonSensor.IFACE_NAME, 'offset', 0)
        self.Set(HwmonSensor.IFACE_NAME, 'filename', '')
        self.value_dirty = False

        # need to cache value to know if changed
        self.value = None
        dbus.service.Object.__init__(self, bus, name)

    @dbus.service.method(
        SensorValue.IFACE_NAME, in_signature='v', out_signature='')
    def setValue(self, value):
        self.value_dirty = True
        SensorValue.setValue(self, value)

    ## Called by sensor process to update value from polling
    ## if returns not None, then sensor process will update hwmon value
    @dbus.service.method(
        IFACE_NAME, in_signature='v', out_signature='(bv)')
    def setByPoll(self, value):
        scale = self.properties[HwmonSensor.IFACE_NAME]['scale']
        offset = self.properties[HwmonSensor.IFACE_NAME]['offset']
        if self.value_dirty:
            ## new value externally set, so just return to hwmon
            ## process to write value
            self.value_dirty = False
            val = (
                self.properties[SensorValue.IFACE_NAME]['value']
                - offset) * scale
            return [True, val]
        else:
            # Keep the val as integer. scale may be floating point
            val = int(value/scale + offset)
            if (val != self.value):
                SensorValue.setValue(self, val)
                self.check_thresholds(val)
                self.value = val

            return [False, 0]


CONTROL_IFACE = 'org.openbmc.Control'


class PowerCap(VirtualSensor):
    def __init__(self, bus, name):
        VirtualSensor.__init__(self, bus, name)
        SensorValue.setValue(self, 0)
        self.sysfs_attr = "/sys/class/hwmon/hwmon3/user_powercap"

    ##override setValue method
    @dbus.service.method(
        SensorValue.IFACE_NAME, in_signature='v', out_signature='')
    def setValue(self, value):
        try:
            cmd_str = "echo "+str(value)+" > "+self.sysfs_attr
            ret = subprocess.check_output(cmd_str, shell=True)
        except subprocess.CalledProcessError as powerexc:
            print "Set PowerCap Error", powerexc.returncode,
            powerexc.output
            return
        print "Set PowerCap: ", value
        SensorValue.setValue(self, value)


class BootProgressSensor(VirtualSensor):
    def __init__(self, bus, name):
        VirtualSensor.__init__(self, bus, name)
        self.setValue("Off")
        bus.add_signal_receiver(
            self.SystemStateHandler, signal_name="GotoSystemState")

    def SystemStateHandler(self, state):
        if (state == "HOST_POWERED_OFF"):
            self.setValue("Off")

    ##override setValue method
    @dbus.service.method(
        SensorValue.IFACE_NAME,
        in_signature='v', out_signature='')
    def setValue(self, value):
        SensorValue.setValue(self, value)
        if (value == "FW Progress, Starting OS"):
            self.GotoSystemState("HOST_BOOTED")

    @dbus.service.signal(CONTROL_IFACE, signature='s')
    def GotoSystemState(self, state):
        pass


class OccStatusSensor(VirtualSensor):
    def __init__(self, bus, name, sysfs=None):
        ## default path. can be override
        if sysfs is None:
            self.sysfs_attr = "/sys/class/i2c-adapter/i2c-3/3-0050/online"
        else:
            self.sysfs_attr = sysfs
        VirtualSensor.__init__(self, bus, name)
        self.setValue("Disabled")
        bus.add_signal_receiver(
            self.SystemStateHandler, signal_name="GotoSystemState")

    def SystemStateHandler(self, state):
        if (state == "HOST_POWERED_OFF"):
            self.setValue("Disabled")

    ##override setValue method
    @dbus.service.method(
        SensorValue.IFACE_NAME, in_signature='v', out_signature='')
    def setValue(self, value):
        if (value == "Enabled"):
            print "Installing OCC device"
            os.system("echo 1 > " + self.sysfs_attr)
        else:
            print "Deleting OCC device"
            os.system("echo 0 > " + self.sysfs_attr)
        SensorValue.setValue(self, value)

    @dbus.service.signal(CONTROL_IFACE, signature='s')
    def GotoSystemState(self, state):
        pass


class BootCountSensor(VirtualSensor):
    def __init__(self, bus, name):
        VirtualSensor.__init__(self, bus, name)
        self.setValue(2)


class OperatingSystemStatusSensor(VirtualSensor):
    def __init__(self, bus, name):
        VirtualSensor.__init__(self, bus, name)
        self.setValue("Off")
        bus.add_signal_receiver(
            self.SystemStateHandler, signal_name="GotoSystemState")

    def SystemStateHandler(self, state):
        if (state == "HOST_POWERED_OFF"):
            self.setValue("Off")