"""
Support for Envisalink-based alarm control panels (Honeywell/DSC).

For more details about this platform, please refer to the documentation at
https://home-assistant.io/components/alarm_control_panel.envisalink/
"""
import asyncio
import logging
import os

import voluptuous as vol

from homeassistant.core import callback
from homeassistant.helpers.dispatcher import async_dispatcher_connect
import homeassistant.components.alarm_control_panel as alarm
import homeassistant.helpers.config_validation as cv
from homeassistant.config import load_yaml_config_file
from homeassistant.components.envisalink import (
    DATA_EVL, EnvisalinkDevice, PARTITION_SCHEMA, CONF_CODE, CONF_PANIC,
    CONF_PARTITIONNAME, SIGNAL_KEYPAD_UPDATE, SIGNAL_PARTITION_UPDATE)
from homeassistant.const import (
    STATE_ALARM_ARMED_AWAY, STATE_ALARM_ARMED_HOME, STATE_ALARM_DISARMED,
    STATE_UNKNOWN, STATE_ALARM_TRIGGERED, STATE_ALARM_PENDING, ATTR_ENTITY_ID)

_LOGGER = logging.getLogger(__name__)

DEPENDENCIES = ['envisalink']

SERVICE_ALARM_KEYPRESS = 'envisalink_alarm_keypress'
ATTR_KEYPRESS = 'keypress'
ALARM_KEYPRESS_SCHEMA = vol.Schema({
    vol.Required(ATTR_ENTITY_ID): cv.entity_ids,
    vol.Required(ATTR_KEYPRESS): cv.string
})


@asyncio.coroutine
def async_setup_platform(hass, config, async_add_devices, discovery_info=None):
    """Perform the setup for Envisalink alarm panels."""
    configured_partitions = discovery_info['partitions']
    code = discovery_info[CONF_CODE]
    panic_type = discovery_info[CONF_PANIC]

    devices = []
    for part_num in configured_partitions:
        device_config_data = PARTITION_SCHEMA(configured_partitions[part_num])
        device = EnvisalinkAlarm(
            hass,
            part_num,
            device_config_data[CONF_PARTITIONNAME],
            code,
            panic_type,
            hass.data[DATA_EVL].alarm_state['partition'][part_num],
            hass.data[DATA_EVL]
        )
        devices.append(device)

    yield from async_add_devices(devices)

    @callback
    def alarm_keypress_handler(service):
        """Map services to methods on Alarm."""
        entity_ids = service.data.get(ATTR_ENTITY_ID)
        keypress = service.data.get(ATTR_KEYPRESS)

        target_devices = [device for device in devices
                          if device.entity_id in entity_ids]

        for device in target_devices:
            device.async_alarm_keypress(keypress)

    # Register Envisalink specific services
    descriptions = yield from hass.loop.run_in_executor(
        None, load_yaml_config_file, os.path.join(
            os.path.dirname(__file__), 'services.yaml'))

    hass.services.async_register(
        alarm.DOMAIN, SERVICE_ALARM_KEYPRESS, alarm_keypress_handler,
        descriptions.get(SERVICE_ALARM_KEYPRESS), schema=ALARM_KEYPRESS_SCHEMA)

    return True


class EnvisalinkAlarm(EnvisalinkDevice, alarm.AlarmControlPanel):
    """Representation of an Envisalink-based alarm panel."""

    def __init__(self, hass, partition_number, alarm_name, code, panic_type,
                 info, controller):
        """Initialize the alarm panel."""
        self._partition_number = partition_number
        self._code = code
        self._panic_type = panic_type

        _LOGGER.debug("Setting up alarm: %s", alarm_name)
        super().__init__(alarm_name, info, controller)

        async_dispatcher_connect(
            hass, SIGNAL_KEYPAD_UPDATE, self._update_callback)
        async_dispatcher_connect(
            hass, SIGNAL_PARTITION_UPDATE, self._update_callback)

    @callback
    def _update_callback(self, partition):
        """Update HA state, if needed."""
        if partition is None or int(partition) == self._partition_number:
            self.hass.async_add_job(self.async_update_ha_state())

    @property
    def code_format(self):
        """Regex for code format or None if no code is required."""
        if self._code:
            return None
        else:
            return '^\\d{4,6}$'

    @property
    def state(self):
        """Return the state of the device."""
        state = STATE_UNKNOWN

        if self._info['status']['alarm']:
            state = STATE_ALARM_TRIGGERED
        elif self._info['status']['armed_away']:
            state = STATE_ALARM_ARMED_AWAY
        elif self._info['status']['armed_stay']:
            state = STATE_ALARM_ARMED_HOME
        elif self._info['status']['exit_delay']:
            state = STATE_ALARM_PENDING
        elif self._info['status']['entry_delay']:
            state = STATE_ALARM_PENDING
        elif self._info['status']['alpha']:
            state = STATE_ALARM_DISARMED
        return state

    @asyncio.coroutine
    def async_alarm_disarm(self, code=None):
        """Send disarm command."""
        if code:
            self.hass.data[DATA_EVL].disarm_partition(
                str(code), self._partition_number)
        else:
            self.hass.data[DATA_EVL].disarm_partition(
                str(self._code), self._partition_number)

    @asyncio.coroutine
    def async_alarm_arm_home(self, code=None):
        """Send arm home command."""
        if code:
            self.hass.data[DATA_EVL].arm_stay_partition(
                str(code), self._partition_number)
        else:
            self.hass.data[DATA_EVL].arm_stay_partition(
                str(self._code), self._partition_number)

    @asyncio.coroutine
    def async_alarm_arm_away(self, code=None):
        """Send arm away command."""
        if code:
            self.hass.data[DATA_EVL].arm_away_partition(
                str(code), self._partition_number)
        else:
            self.hass.data[DATA_EVL].arm_away_partition(
                str(self._code), self._partition_number)

    @asyncio.coroutine
    def async_alarm_trigger(self, code=None):
        """Alarm trigger command. Will be used to trigger a panic alarm."""
        self.hass.data[DATA_EVL].panic_alarm(self._panic_type)

    @callback
    def async_alarm_keypress(self, keypress=None):
        """Send custom keypress."""
        if keypress:
            self.hass.data[DATA_EVL].keypresses_to_partition(
                self._partition_number, keypress)
