#!/usr/bin/python -u

import sys
import os
import gobject
import glob
import dbus
import dbus.service
import dbus.mainloop.glib
import Openbmc
import re

from Sensors import SensorValue as SensorValue
from Sensors import HwmonSensor as HwmonSensor
from Sensors import SensorThresholds as SensorThresholds

if (len(sys.argv) < 2):
	print "Usage:  sensors_hwmon.py [system name]"
	exit(1)

System = __import__(sys.argv[1])

SENSOR_BUS = 'org.openbmc.Sensors'
SENSOR_PATH = '/org/openbmc/sensors'
DIR_POLL_INTERVAL = 30000
HWMON_PATH = '/sys/class/hwmon'

## static define which interface each property is under
## need a better way that is not slow
IFACE_LOOKUP = {
	'units' : SensorValue.IFACE_NAME,
	'scale' : HwmonSensor.IFACE_NAME,
	'offset' : HwmonSensor.IFACE_NAME,
	'critical_upper' : SensorThresholds.IFACE_NAME,
	'warning_upper' : SensorThresholds.IFACE_NAME,
	'critical_lower' : SensorThresholds.IFACE_NAME,
	'warning_lower' : SensorThresholds.IFACE_NAME,
	'emergency_enabled' : SensorThresholds.IFACE_NAME,
}

class Hwmons():
	def __init__(self,bus):
		self.sensors = { }
		self.hwmon_root = { }
		self.scanDirectory()
		gobject.timeout_add(DIR_POLL_INTERVAL, self.scanDirectory)   
		self.cache = {}

	def readAttribute(self,filename):
		val = "-1"
		try:
		with open(filename, 'r') as f:
			for line in f:
				val = line.rstrip('\n')
		except (OSError, IOError):
		print "Cannot read attributes:", filename
		return val

	def writeAttribute(self,filename,value):
		with open(filename, 'w') as f:
			f.write(str(value)+'\n')

	def should_update(attribute, value):
		if attribute not in self.cache:
			self.cache[attribute] = value
			return True

		update = (value != self.cache[attribute])
		self.cache[attribute] = value

		return update

	def poll(self,objpath,attribute):
		try:
			raw_value = int(self.readAttribute(attribute))
			if self.should_update(attribute, raw_value):
				obj = bus.get_object(SENSOR_BUS,objpath,introspect=False)
				intf = dbus.Interface(obj,HwmonSensor.IFACE_NAME)
				rtn = intf.setByPoll(raw_value)
				if (rtn[0] == True):
					self.writeAttribute(attribute,rtn[1])
		except:
			print "HWMON: Attibute no longer exists: "+attribute
			self.sensors.pop(objpath,None)
			if attribute in self.cache:
				del self.cache[attribute]
			return False


		return True


	def addObject(self,dpath,hwmon_path,hwmon):
		objsuf = hwmon['object_path']
		objpath = SENSOR_PATH+'/'+objsuf
		
		if (self.sensors.has_key(objpath) == False):
			print "HWMON add: "+objpath+" : "+hwmon_path

			## register object with sensor manager
			obj = bus.get_object(SENSOR_BUS,SENSOR_PATH,introspect=False)
			intf = dbus.Interface(obj,SENSOR_BUS)
			intf.register("HwmonSensor",objpath)

			## set some properties in dbus object		
			obj = bus.get_object(SENSOR_BUS,objpath,introspect=False)
			intf = dbus.Interface(obj,dbus.PROPERTIES_IFACE)
			intf.Set(HwmonSensor.IFACE_NAME,'filename',hwmon_path)
			
			## check if one of thresholds is defined to know
			## whether to enable thresholds or not
			if (hwmon.has_key('critical_upper')):
				intf.Set(SensorThresholds.IFACE_NAME,'thresholds_enabled',True)

			for prop in hwmon.keys():
				if (IFACE_LOOKUP.has_key(prop)):
					intf.Set(IFACE_LOOKUP[prop],prop,hwmon[prop])
					print "Setting: "+prop+" = "+str(hwmon[prop])

			self.sensors[objpath]=True
			self.hwmon_root[dpath].append(objpath)
			gobject.timeout_add(hwmon['poll_interval'],self.poll,objpath,hwmon_path)
	
	def scanDirectory(self):
	 	devices = os.listdir(HWMON_PATH)
		found_hwmon = {}
		regx = re.compile('([a-z]+)\d+\_')
		for d in devices:
			dpath = HWMON_PATH+'/'+d+'/'
			found_hwmon[dpath] = True
			if (self.hwmon_root.has_key(dpath) == False):
				self.hwmon_root[dpath] = []
			## the instance name is a soft link
			instance_name = os.path.realpath(dpath+'device').split('/').pop()
			
			
			if (System.HWMON_CONFIG.has_key(instance_name)):
				hwmon = System.HWMON_CONFIG[instance_name]
	 			
				if (hwmon.has_key('labels')):
					label_files = glob.glob(dpath+'/*_label')
					for f in label_files:
						label_key = self.readAttribute(f)
						if (hwmon['labels'].has_key(label_key)):
							namef = f.replace('_label','_input')
							self.addObject(dpath,namef,hwmon['labels'][label_key])
						else:
							pass
							#print "WARNING - hwmon: label ("+label_key+") not found in lookup: "+f
							
				if hwmon.has_key('names'):
					for attribute in hwmon['names'].keys():
						self.addObject(dpath,dpath+attribute,hwmon['names'][attribute])
						
			else:
				print "WARNING - hwmon: Unhandled hwmon: "+dpath
	

		for k in self.hwmon_root.keys():
			if (found_hwmon.has_key(k) == False):
				## need to remove all objects associated with this path
				print "Removing: "+k
				for objpath in self.hwmon_root[k]:
					if (self.sensors.has_key(objpath) == True):
						print "HWMON remove: "+objpath
						self.sensors.pop(objpath,None)
						obj = bus.get_object(SENSOR_BUS,SENSOR_PATH,introspect=False)
						intf = dbus.Interface(obj,SENSOR_BUS)
						intf.delete(objpath)

				self.hwmon_root.pop(k,None)
				
		return True

			
if __name__ == '__main__':
	
	dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
	bus = Openbmc.getDBus()
	root_sensor = Hwmons(bus)
	mainloop = gobject.MainLoop()

	print "Starting HWMON sensors"
	mainloop.run()