#!/usr/bin/env python

import os
import sys
import datetime
import yaml

def contexts(device, config_contexts):
  # print(f'device: {device}')
  all_config_contexts = {}

  def remove_meta(data):
    try:
      del data['_metadata']
    except KeyError:
      pass
    return data

  # get device context
  try:
    with open(f'./config_contexts/device/{device}.yml', 'r') as file:
      data = yaml.safe_load(file)
      all_config_contexts.update({'device': {'weight': 0, 'content': remove_meta(data)}})
  except:
    pass

  # get config_contexts
  for k, v in config_contexts.items():
    islist = False
    if isinstance(v, list):
      islist = True
      vlist = v
    else:
      vlist = [v]
    for i in vlist:
      try:
        if islist:
          context_name = f'{k}_{i}'
        else:
          context_name = k
        with open(f'./config_contexts/{k}/{i}.yml', 'r') as file:
          data = yaml.safe_load(file)
        if data['_metadata']['weight'] and data['_metadata']['is_active']:
            all_config_contexts.update({context_name: {'weight': data['_metadata']['weight'], 'content': remove_meta(data)}})
      except:
        pass

  # get the all context
  all_weight = sorted([all_config_contexts[k]['weight'] for k, v in all_config_contexts.items()], reverse=True)
  dupe_weight = list(set([x for x in all_weight if all_weight.count(x) > 1]))
  max_weight = all_weight[0]+1
  try:
    with open('./config_contexts/all.yml', 'r') as file:
      data = yaml.safe_load(file)
      if data['_metadata']['is_active']:
        all_config_contexts.update({'all': {'weight': max_weight, 'content': remove_meta(data)}})
  except:
    pass  
  # print(yaml.dump(all_config_contexts))

  # check for equally weighted clashing keys
  equal_weight = {}
  for i in dupe_weight:
    equal_weight.update({i: []})
    for k in all_config_contexts.keys():
      if all_config_contexts[k]['weight'] == i:
        equal_weight[i].append(k)
  # print(f'equal weight contexts: {equal_weight}')
  
  # list all keys in equally weighted contexts
  keys_list = []
  for k in equal_weight.keys():
    for i in equal_weight[k]:
      for k in all_config_contexts[i]['content'].keys():
        keys_list.append(k)
  keys_list = list(set(keys_list))
  # print(f'all keys in equal weight contexts: {keys_list}')

  # check each equally weighted context for clashing keys
  equal_weight_key_clash_errors = []
  for w in equal_weight:
    for k in keys_list:
      key_occurance = []
      for i in equal_weight[w]:
        if k in all_config_contexts[i]['content']:
          key_occurance.append(i)
      if len(key_occurance) >1:
        equal_weight_key_clash_errors.append(f'clashing key found in equally weighted contexts: \nkey: {k} \ncontexts: {key_occurance}')
  if len(equal_weight_key_clash_errors) >0:
    error_log = f'device config_context render issue: {device}\n'
    for i in equal_weight_key_clash_errors:
      error_log = error_log + f'\n{i}\n'
    print(error_log)
    return

  # reorder all_config_contexts by weight, update the config_context with each context in order of precedence, overwriting keys where they exist (the last context being the lowest weight and highest precedence)
  config_context = {}
  all_config_contexts = {k: v for k, v in sorted(all_config_contexts.items(), key=lambda x: x[1]['weight'], reverse=True)}
  for k, v in all_config_contexts.items():
    config_context = {**config_context, **v['content']}
  config_context = dict(sorted(config_context.items()))
  print(yaml.dump(config_context))
  return config_context

def main():
  with open('./inventory.yml', 'r') as file:
    data = yaml.safe_load(file)
  for i in data.keys():
    contexts(i, data[i]['config_contexts'])

if __name__ == "__main__":
    main()

  # what does this need to do?
  # render a config_context
  # render a jinja2 template
  # print out a rendered context for someone when writing jinja2 templates