#!/usr/bin/env python3
# File: j2c.py
# Location: https://gitlab.com/bgstack15/j2c
# Author: bgstack15
# Startdate: 2021-01-16
# SPDX-License-Identifier: CC-BY-SA-4.0
# Title: Json To CSV Library for Python
# Purpose: NIH
# History:
# Usage:
# Reference:
# Improve:
# Documentation:
# vim: set ts=3 sw=3 sts=3 et:
import json, sys, os

# default debug level for this library
debug = 0

def load_json_file(filename):
   _lof=[]
   with open(filename,"r") as f:
      _lof = json.load(f)
   return _lof

def debugprint(dstring,debug=debug):
   if debug >= 1:
      print(dstring)

def print_json(json_obj,indent=1):
   print(json.dumps(json_obj,indent=indent))

def convert_json_to_csv(json_objorfile,csvfile="stdout",debug=debug):

   try:
      if os.path.exists(json_objorfile):
         json_obj = load_json_file(json_objorfile)
   except:
      json_obj = json_objorfile
      print("json_obj=",json_obj)

   # Learn keys at this level
   keys=[]
   for i in json_obj:
      for j in list(i.keys()):
         if j not in keys:
            keys.append(j)
            debugprint("Found key {0}".format(j),debug=debug)

   #for k in keys:
   #    print(k)

   x=0
   fullstring=""
   for i in json_obj:
      x += 1
      # only if there are actually contents of "all" do we print the headers
      if x == 1:
         for k in keys:
            fullstring += str(k) + ","
         fullstring += "\n"
      for k in keys:
         p = ""
         try:
            p = str(i[k]).replace(",",":")
         except:
            # no value for this key for this entry
            pass
         pp = "{0},".format(p)
         fullstring += pp
      fullstring += "\n"

   if fullstring != "":
      if csvfile == "stdout":
         print(fullstring)
      else:
         with open(csvfile,"a") as of:
            of.write(fullstring)