#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import sys, requests, json

# Script POSTs coordinates for NtC assignment to DNATCO web server

################# settings #################
# using the default DNATCO version (v3.2 as of 03 Aug 2021) with NtC alphabet version 3.5
dnatco_cgi = "https://dnatco.datmos.org/cgi-bin/assign_from_coords_35.py"
# set user agent for logging purposes
headers = {'user-agent': 'POST_json_coords.py/0.0.2'}
############################################

# Step name and coordinates of 20 atoms within a step are needed.
# Atom names use "p" instead of "'" (prime) and "a/b" for first/second residue within a step.
# Purine/pyrimidine atom names are combined to "N19" and "C24" for simplicity.
# Coordinates in Angstroms are expected as strings in x,y,z order for each atom, i.e. ["x.x", "y.y", "z.z"]

# use example json query ...
#query = '{"step_id":"102d_A_DC_1_DG_2","C5pa":["18.939","34.713","89.428"],"C4pa":["20.086","33.755","89.286"],"O4pa":["19.617","32.539","89.905"],"C3pa":["20.434","33.382","87.819"],"O3pa":["21.831","32.949","87.719"],"C2pa":["19.488","32.196","87.629"],"C1pa":["19.521","31.485","88.974"],"N19a":["18.313","30.732","89.375"],"C24a":["18.488","29.453","89.907"],"Pb":["22.636","32.521","86.331"],"O5pb":["22.776","30.956","86.326"],"C5pb":["23.239","30.276","87.446"],"C4pb":["23.441","28.853","87.109"],"O4pb":["22.221","28.177","87.390"],"C3pb":["23.649","28.619","85.571"],"O3pb":["24.497","27.474","85.326"],"C2pb":["22.244","28.333","85.091"],"C1pb":["21.634","27.584","86.246"],"N19b":["20.190","27.715","86.370"],"C24b":["19.318","26.753","86.864"]}'

# ... or read prepared json from cmdline
query = sys.argv[1]

try:
  # POST json query to DNATCO
  r = requests.post(dnatco_cgi, json=json.loads(query), headers=headers)
  # decode returned json
  jsonres = r.json()
except Exception as e:
  print(repr(e))
  sys.exit()

# "error" is empty for successful assignment
if (jsonres["error"] == ""):
  # save json output to file
  try:
    out = open(jsonres["result"]["step_id"] + ".json", "w")
    json.dump(jsonres, out)
    out.close()
  except:
    print("Error writing output json file")
    pass

  # process json output
  # print full output
  #print(jsonres)

  # and/or only selected summary
  print(jsonres["result"]["NtC"], jsonres["result"]["nearest_NtC"], jsonres["result"]["confalH"], jsonres["result"]["rmsd"])
else:
  print(jsonres["error"])