#!/usr/bin/env python

#############################################################################
# Celestica
#
# Module contains an implementation of SONiC Platform Base API and
# provides the Chassis information which are available in the platform
#
#############################################################################

import sys
import re
import os
import subprocess
import json

try:
    from sonic_platform_base.chassis_base import ChassisBase
    from sonic_platform.fan import Fan
    from sonic_platform.psu import Psu
except ImportError as e:
    raise ImportError(str(e) + "- required module not found")

BIOS_VERSION_PATH = "/sys/class/dmi/id/bios_version"
GETREG_PATH = "/sys/devices/platform/dx010_cpld/getreg"
CONFIG_DB_PATH = "/etc/sonic/config_db.json"
NUM_FAN = 5
NUM_PSU = 2
CPLD_ADDR_MAPPING = {
    "CPLD1": "0x100",
    "CPLD2": "0x200",
    "CPLD3": "0x280",
    "CPLD4": "0x300",
    "CPLD5": "0x380"
}


class Chassis(ChassisBase):
    """Platform-specific Chassis class"""

    def __init__(self):
        self.config_data = {}
        for index in range(0, NUM_FAN):
            fan = Fan(index)
            self._fan_list.append(fan)
        for index in range(0, NUM_PSU):
            psu = Psu(index)
            self._psu_list.append(psu)
        ChassisBase.__init__(self)

    def __get_register_value(self, path, register):
        cmd = "echo {1} > {0}; cat {0}".format(path, register)
        p = subprocess.Popen(
            cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        raw_data, err = p.communicate()
        if err is not '':
            return 'None'
        else:
            return raw_data.strip()

    def __read_config_db(self):
        try:
            with open(CONFIG_DB_PATH, 'r') as fd:
                data = json.load(fd)
                return data
        except IOError:
            raise IOError("Unable to open config_db file !")

    def get_base_mac(self):
        """
        Retrieves the base MAC address for the chassis
        Returns:
            A string containing the MAC address in the format
            'XX:XX:XX:XX:XX:XX'
        """
        try:
            self.config_data = self.__read_config_db()
            base_mac = self.config_data["DEVICE_METADATA"]["localhost"]["mac"]
            return str(base_mac)
        except KeyError:
            raise KeyError("Base MAC not found")

    def get_component_versions(self):
        """
        Retrieves platform-specific hardware/firmware versions for chassis
        componenets such as BIOS, CPLD, FPGA, etc.
        Returns:
            A string containing platform-specific component versions
        """

        component_versions = dict()

        # Get BIOS version
        try:
            with open(BIOS_VERSION_PATH, 'r') as fd:
                bios_version = fd.read()
        except IOError:
            raise IOError("Unable to open version file !")

        # Get CPLD version
        cpld_version = dict()
        for cpld_name in CPLD_ADDR_MAPPING:
            try:
                cpld_addr = CPLD_ADDR_MAPPING[cpld_name]
                cpld_version_raw = self.__get_register_value(
                    GETREG_PATH, cpld_addr)
                cpld_version_str = "{}.{}".format(int(cpld_version_raw[2], 16), int(
                    cpld_version_raw[3], 16)) if cpld_version_raw is not None else 'None'
                cpld_version[cpld_name] = cpld_version_str
            except Exception, e:
                cpld_version[cpld_name] = 'None'
        component_versions["CPLD"] = cpld_version
        component_versions["BIOS"] = bios_version.strip()
        return str(component_versions)