# Version: 1
# Author: Joachim Olsson
# Email: joachim.olsson@gcf-consulting.com
# Date: 2016-10-05
#
# This file detects hardware pulses from energy meter and logs them
# The default input pin is GPIO24 on raspberry pi
# Each tick on this pin is worth 10 Wh
# This is stored in memory, and written to file by default once every minute

import RPi.GPIO as GPIO
import datetime
import time
import os
import sys
import linecache
import requests
import json
import threading
from random import randint, uniform
import re

def RunScript(script):
    os.system('sudo python ' + script)

def LogException(Info):
	f = None
	try:
		LoggingLock.acquire()
		locked = True
		f = open(os.getcwd() + LogFile, "a+")
		dateTime = datetime.datetime.utcnow()
		data = f.read()
		f.seek(0)
		f.truncate()
		jsonData = json.loads(data)
		jsonData['ExceptionEntries'].append({'Time': dateTime.isoformat(), 'Exception': Info})
		f.write(json.dumps(jsonData))
	except ValueError as ex:
		#Error in data, input valid sequence in file
		print "LogException: "
		print ex
		print 'Decoding JSON failed! Document:'
		print data
		jsonData = {
				'LogEntries': [],
				'DeviceEntries': [],
				'ExceptionEntries': [{'Time': dateTime.isoformat(), 'ExceptionInfo': Info}]
		}

		f.write(json.dumps(jsonData))
		print '\nJSON Data Restored!'
		locked = False
		f.close()
		LoggingLock.release()
		LogAction('TRUNCATING DATA: (Log Exception ValueError)')
	except Exception as ex:
		f.close()
		locked = False
		LoggingLock.release()
		LogExceptionInfo()
	finally:
		if(f and not f.closed):
			f.close()
		if(locked):
			LoggingLock.release()

def LogExceptionInfo():
	try:
		exc_type, exc_obj, tb = sys.exc_info()
		f = tb.tb_frame
		lineno = tb.tb_lineno
		filename = f.f_code.co_filename
		linecache.checkcache(filename)
		line = linecache.getline(filename, lineno, f.f_globals)
		dateTime = datetime.datetime.utcnow()
		text = '[{}] EXCEPTION OCCURRED IN ({}, LINE {} "{}"): {}'.format(dateTime, filename, lineno, line.strip(), exc_obj)
		print text
		LogException(text)
	except ValueError as ex:
		print ex
		LogExceptionInfo()
	except Exception as ex:
		LogExceptionInfo()

def GetAuthorizationToken():
	try:
		AuthorizationLock.acquire()
		locked = True
		global AuthorizationType, AuthorizationCredentials, AuthorizationExpires, Authorized
		data = {
			'username': LoginAccountUsername,
			'password': LoginAccountPassword,
			'grant_type': 'password'
		}
		response = requests.post(BaseAuth, data = data)
		data = response.json()

		if(response.status_code == 200):
			AuthorizationExpires = datetime.datetime.utcnow() + datetime.timedelta(seconds=data['expires_in']) - datetime.timedelta(seconds=1)
			AuthorizationCredentials = data['access_token']
			AuthorizationType = "Bearer "
			Authorized = True
			print "Authorization Expires at: " + str(AuthorizationExpires)
			print "Authorization Type: " + str(AuthorizationType)
			print "Authorization Credentials: " + str(AuthorizationCredentials)
			LogAction("LOGIN SUCCESS")
		else:
			Authorized = False
			LogAction("LOGIN FAIL")
	except:
		LogExceptionInfo()
	finally:
		if(locked):
			AuthorizationLock.release()

def GetUpdates():
	f = None
	success = False
	try:
		AuthorizationLock.acquire()
		headers = { "Authorization" : AuthorizationType + AuthorizationCredentials, "Accept": "text/*", "Accept-Encoding": "gzip;q=1.0, deflate;q=0.8, *;q=0" }
		response = requests.get(BaseAPI + "/Logging/GetUpdater", headers = headers)
		disposition = response.headers['content-disposition']
		filename = re.findall("filename=(.+)", disposition)[0]

		f = open(os.getcwd() + "/" + filename, "a+")
		f.seek(0)
		f.truncate()
		f.write(unicode(response.content, "UTF-8"))
		LogAction("DOWNLOAD UPDATER: " + filename)
		print "Downloaded Updater: " + filename
		success = True
	except:
		LogExceptionInfo()
	finally:
		AuthorizationLock.release()
		if(f and not f.closed):
			f.close()

	if(success):
		try:
			RunScript(os.getcwd() + "/" + filename)
			LogAction("OS EXIT (UPDATING...)")
			os._exit(1)
		except:
			LogExceptionInfo()

def GetConfig():
	global Authorized, HardwareLogInterval, PostInterval
	LatestBuild = CurrentBuild
	try:
		AuthorizationLock.acquire()
		locked = True
		authorized = Authorized
	except:
		LogExceptionInfo()
	finally:
		if(locked):
			AuthorizationLock.release()

	try:
		if(not authorized):
			GetAuthorizationToken()
	except:
		LogExceptionInfo()

	try:
		AuthorizationLock.acquire()
		locked = True
		headers = { "Authorization" : AuthorizationType + AuthorizationCredentials, "Accept": "application/json", "Accept-Encoding": "gzip;q=1.0, deflate;q=0.8, *;q=0" }
		response = requests.get(BaseAPI + "/Logging/GetConfig", headers = headers)
		data = response.json()
		if(response.status_code == 200):
			try:
				ConfigLock.acquire()
				Status = data['Status']
				HardwareLogInterval = datetime.timedelta(seconds=data['LogInterval'])
				PostInterval = datetime.timedelta(seconds=data['PostInterval'])
				NextLogTime = datetime.datetime.utcnow() + HardwareLogInterval
				NextPostTime = datetime.datetime.utcnow() + PostInterval
				LatestBuild = data['LatestBuild']
				'''print "Retrieved config"
				print "Status: " + str(Status)
				print "LogInterval: " + str(HardwareLogInterval)
				print "PostInterval: " + str(PostInterval)'''
				LogAction("GET CONFIG")
			except:
				LogExceptionInfo()
			finally:
				ConfigLock.release()
		else:
			authorized = False
			LogAction("GET CONFIG FAIL")
	except:
		LogExceptionInfo()
	finally:
		if(locked):
			AuthorizationLock.release()

	try:
		if(not authorized):
			GetAuthorizationToken()
	except:
		LogExceptionInfo()

	if(LatestBuild != CurrentBuild):
		GetUpdates()

def GetCPUSerial():
	cpuSerial = '0000000000000000'
	try:
		f = open('/proc/cpuinfo','r') #RPi Serial location
		for line in f:
			if line[0:6]=='Serial':
				cpuSerial = line[10:26]
		return int(str(cpuSerial), 16)
	except Exception as ex:
		LogExceptionInfo()
	finally:
		f.close()

def StartHardwareLogger():
	try:
		print "StartHardwareLogger"
		GPIO.setwarnings(False)
		GPIO.setmode(GPIO.BCM)
		GPIO.setup(HardwarePin, GPIO.IN, pull_up_down=GPIO.PUD_DOWN)
		GPIO.add_event_detect(HardwarePin, GPIO.RISING, callback=HardwareLoggerCallback, bouncetime=BounceIntervalMs)
	except:
		LogExceptionInfo()

def HardwareLoggerCallback(ch):
	try:
		global CurrentEnergyLevel,CountEnergyTicks,DateTime,NextLogTime
		CurrentEnergyLevel += 10
		CountEnergyTicks += 1
		DateTime = datetime.datetime.utcnow()
		if(DateTime >= NextLogTime and CurrentEnergyLevel > 0):
			NextLogTime = DateTime + HardwareLogInterval
			LogEntry(CurrentEnergyLevel)
			CurrentEnergyLevel = 0
		'''if (CountEnergyTicks >= 3):
			print "HardwareLoggerCallback 3"
			GPIO.remove_event_detect(HardwarePin)
			GPIO.cleanup()
			StartHardwareLogger()'''
	except:
		#GPIO.cleanup()
		LogExceptionInfo()
		#StartHardwareLogger()

def LogEntry(EnergyLevel):
	f = None
	try:
		LoggingLock.acquire()
		locked = True
		f = open(os.getcwd() + LogFile, "a+")
		dateTime = datetime.datetime.utcnow()
		data = f.read()
		f.seek(0)
		f.truncate()
		jsonData = json.loads(data)
		jsonData['LogEntries'].append({
				'Time': dateTime.isoformat(),
				'EnergyAmount': EnergyLevel,
				})
		f.write(json.dumps(jsonData))
	except ValueError as ex:
		#Error in data, input valid sequence in file
		print 'Decoding JSON failed! Document:'
		print data
		jsonData = {
				'LogEntries': [{
						'Time': dateTime.isoformat(),
						'EnergyAmount': EnergyLevel
						}],
				'DeviceEntries': [],
				'ExceptionEntries': []
		}
		f.write(json.dumps(jsonData))
		f.close()
		locked = False
		LoggingLock.release()
		print 'JSON Data Restored!'
		LogAction("TRUNCATING DATA: (Log Entry ValueError)")
	except Exception as ex:
		if(f and not f.closed):
			f.close()
		locked = False
		LoggingLock.release()
		LogExceptionInfo()
	finally:
		if(f and not f.closed):
			f.close()
		if(locked):
			LoggingLock.release()

def LogAction(Info):
	f = None
	try:
		LoggingLock.acquire()
		locked = True
		f = open(os.getcwd() + LogFile, "a+")
		dateTime = datetime.datetime.utcnow()
		data = f.read()
		f.seek(0)
		f.truncate()
		jsonData = json.loads(data)
		jsonData['DeviceEntries'].append({'Time': dateTime.isoformat(), 'Action': Info})
		f.write(json.dumps(jsonData))
	except ValueError as ex:
		#Error in data, input valid sequence in file
		print 'Decoding JSON failed! Document:'
		print data
		jsonData = {
				'LogEntries': [],
				'DeviceEntries': [{'Time': dateTime.isoformat(), 'Action': Info}],
				'ExceptionEntries': []
		}
		f.write(json.dumps(jsonData))
		locked = False
		f.close()
		LoggingLock.release()
		print 'JSON Data Restored!'
		LogAction("TRUNCATING DATA: (Log Action ValueError)")
	except Exception as ex:
		if(f and not f.closed):
			f.close()
		locked = False
		LoggingLock.release()
		LogExceptionInfo()
	finally:
		if(f and not f.closed):
			f.close()
		if(locked):
			LoggingLock.release()

def CheckAuthorize():
	global Authorized
	if(datetime.datetime.utcnow() >= AuthorizationExpires):
		AuthorizationLock.acquire()
		print "Authorization Invalid"
		Authorized = False
		AuthorizationLock.release()
		while(True):
			print "Re-authorizing"
			GetAuthorizationToken()
			if(Authorized):
				break
			else:
				time.sleep(30)

def CheckPostLog():
	global NextPostTime, PostInterval, HardwareLogInterval, NextLogTime, Status
	f = None
	LatestBuild = CurrentBuild
	if(datetime.datetime.utcnow() >= NextPostTime):
		try:
			print "Posting log..."
			LoggingLock.acquire()
			locked = True
			NextPostTime = datetime.datetime.utcnow() + PostInterval
			f = open(os.getcwd() + LogFile, "a+")
			jsonData = json.loads(f.read())
			jsonData['Time'] = datetime.datetime.utcnow().isoformat()
			headers = { "Authorization" : AuthorizationType + AuthorizationCredentials, "Accept": "application/json", "Content-Type": "application/json" }
			response = requests.post(BaseAPI + "/Logging/Log", headers = headers, json=jsonData)
			data = response.json()
			if(response.status_code == 200):
				f.seek(0)
				f.truncate()
				jsonData = {
						'LogEntries': [],
						'DeviceEntries': [],
						'ExceptionEntries': []
				}
				f.write(json.dumps(jsonData))
				try:
					ConfigLock.acquire()
					Status = data['Status']
					HardwareLogInterval = datetime.timedelta(seconds=data['LogInterval'])
					PostInterval = datetime.timedelta(seconds=data['PostInterval'])
					NextLogTime = datetime.datetime.utcnow() + HardwareLogInterval
					NextPostTime = datetime.datetime.utcnow() + PostInterval
					LatestBuild = data['LatestBuild']
				except Exception as ex:
					LogAction("SAVE POST LOG CONFIG FAILURE: { DATA: { " + data + " }, EXCEPTION: {" + ex + " } ")
				finally:
					ConfigLock.release()
			else:
				LogAction("POST LOG FAILURE: " + str(data))
				print "Error Sending Log: "
				print data
		except ValueError as ex:
			if(f and not f.closed):
				f.seek(0)
				f.truncate()
				jsonData = {
					'LogEntries': [],
					'DeviceEntries': [],
					'ExceptionEntries': []
				}
				f.write(json.dumps(jsonData))
				locked = False
				LoggingLock.release()
				LogAction("TRUNCATING DATA: (POST LOG ValueError)")
		except:
			if(f and not f.closed):
				f.close()
			locked = False
			LoggingLock.release()
			LogExceptionInfo()
		finally:
			if(f and not f.closed):
				f.close()
			if(locked):
				LoggingLock.release()

		try:
			if(LatestBuild != CurrentBuild):
				GetUpdates()
		except:
			LogExceptionInfo()




########-----Global Variables-----########
ConfigLock = threading.Lock()

Status = 0
PostInterval = datetime.timedelta(seconds=3)
HardwareLogInterval = datetime.timedelta(seconds=5) #How often to log to file
DateTime = datetime.datetime.utcnow()
NextLogTime = DateTime + HardwareLogInterval
NextPostTime = DateTime + PostInterval
BounceIntervalMs = 50 #Note, anything logged in this interval won't be counted
HardwarePin = 24 #GPIO24


AuthorizationLock = threading.Lock()

BaseAPI = "http://192.168.1.16:8080/API/"
BaseAuth = "http://192.168.1.16:8080/oauth/token"
AuthorizationType = ""
AuthorizationCredentials = ""
AuthorizationExpires = datetime.datetime.utcnow() - datetime.timedelta(hours=1)
Authorized = False
LoginAccountUsername = "Device@AndrewPeters"
LoginAccountPassword = "p4ssw0rd"


LoggingLock = threading.Lock()

CurrentEnergyLevel = 0
CountEnergyTicks = 0
#CPUSerial = GetCPUSerial()
LogFile = "/Log.json"
UpdaterFile = "/Updater.py"
CurrentBuild = 2

########-----Main Program-----########
print "\n==================="
print "PowerCoins Logger - Running"
print "===================\n"

while True:
	try:
		LogAction("BOOT")
		#StartHardwareLogger()
		CheckAuthorize()
		GetConfig()
		while True:
			print "Looping"
			approachingRandom = 50
			lastRandom = 50
			if(randint(0,15) > 14):
				if(lastRandom == approachingRandom):
					approachingRandom = randint(30, 120)
				lastRandom = round((approachingRandom - lastRandom) * uniform(0, 1), 0)
				LogEntry(lastRandom)

			CheckAuthorize()
			CheckPostLog()
			time.sleep(3) #To give time to OS to relax

	except Exception as e:
		print e
		LogAction("EXIT(AUTORESTART)")
		GPIO.cleanup()