#!/usr/bin/python -u

import sys
import os
import gobject
import glob
import dbus
import dbus.service
import dbus.mainloop.glib
import re
from obmc.dbuslib.bindings import get_dbus

from obmc.sensors import SensorValue as SensorValue
from obmc.sensors import HwmonSensor as HwmonSensor
from obmc.sensors import SensorThresholds as SensorThresholds
import obmc_system_config as System

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(self, 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 = get_dbus()
	root_sensor = Hwmons(bus)
	mainloop = gobject.MainLoop()

	print "Starting HWMON sensors"
	mainloop.run()