#Java Script Object Notation is the format that the Kentucky Mesonet Data is stored in.
import json
import os
from datetime import datetime, timedelta
#There are a lot of ways to format and work with time in python, all Mesonet data is stored in the timestamp format "YYYY-MM-DD HH:MM:SS" and will be in UTC/GMT timezone
#This variable is handy for exporting timestamps in a consistent way
tsdef = '%Y-%m-%d %H:%M:%S'

#This gets the absolute dir the script is currently in
scriptDir = os.path.dirname(__file__) 
print(scriptDir)

#This is a file that contains tons of meta information about our station locations
metafile = open('StationsInfo.json')

#This loads the information in the son into a dict
metadata = json.load(metafile)

#After loading the data we can close the file
metafile.close()

#for station in metadata:
#	print(metadata[station]["county"])

#human readable timestamps nice simple copy-pasteable
beginTimestamp = "2020-04-01 00:00:00"
endTimestamp = "2020-04-14 00:00:00"

#timestamps for the computer to work with
beginTime = datetime.strptime(beginTimestamp, tsdef)
endTime = datetime.strptime(endTimestamp, tsdef)

#Find out how many days we will be itterating over
dayCount = (endTime - beginTime).days + 1

#Station Abbrevations can be found in the metadata file
stationAbbrev = "FARM"

#Variiable Abbreviations can be found in the defenition document provided
variableAbbrev = "TAIR"

#A simple for loop starting at beginTime and then adding 1 day per loop until we have reached the end defined by endTime
for dataTime in (beginTime + timedelta(n) for n in range(dayCount)):
	
	#Start with existing script location from before and add the variable name
	filePath=scriptDir +"\\"+variableAbbrev
	#Add the year
	filePath = filePath + "\\" + dataTime.strftime("%Y")
	#Add the month
	filePath = filePath + "\\" + dataTime.strftime("%m")
	#Add the day
	filePath = filePath + "\\" + dataTime.strftime("%d")
	#Add the data period + station ID + file extension
	filePath = filePath + "\\" + "05_"+ stationAbbrev +".json"

	#Open the json file at the location we have specified
	datafile = open(filePath)
	#Load the JSON into an object creating a dict
	currentJson = json.load(datafile)
	#Close the file as we wont need it anymore
	datafile.close()
	#Find the sum of the elements in the file
	dailySum = sum(currentJson["val"])
	#Find the count of the elements in the file (for a complete day of data at the Mesonet it will be 288 (24*60 / 5))
	dailyCount = len(currentJson["val"])
	#Find the average and do some rounding to make the display nice
	dailyAverage = round(dailySum/dailyCount,2)

	#Finally we print out the information
	print("The average of "+ variableAbbrev +" for "+ stationAbbrev +" on " + dataTime.strftime("%Y-%m-%d") + " was " + str(dailyAverage) +", " + str(dailyCount) + " obs were made.")