from db import get_bill_data, get_bill_types, set_bill_type_growth

def derive_bill_data():
  bd=get_bill_data()
  bt=get_bill_types()
  water_id = None
  for t in bt:
    if t['name'] == "Water":
        water_id = t['id']

  if not water_id:
    return
  total={}
  total[water_id]={}
  for yr in [2022, 2023, 2024]:
      print( f"water_id={water_id}")
      total[water_id][yr] = 0
      for b in bd:
        if b['bill_type_id'] == water_id and str(yr) in b['bill_date']:
            total[water_id][yr] += b['amount']
            print( f"{yr} => {b['bill_date']} -- {b['amount']}" )
      print( f"total for water in {yr} is {total[water_id][yr]}" )

  # once we have all yr totals:
  growth = {}
  growth[water_id] = {}
  max_growth = {}
  avg_growth = {}
  max_growth[water_id] = 0
  avg_growth[water_id] = 0
  count = 0
  for yr in [2023, 2024]:
    growth[water_id][yr] = (total[water_id][yr] - total[water_id][yr-1]) / total[water_id][yr-1] * 100
    avg_growth[water_id] += growth[water_id][yr]
    count += 1
    if growth[water_id][yr] > max_growth[water_id]:
        max_growth[water_id] = growth[water_id][yr]
    print( f"growth from {yr} to {yr-1} = {growth}%")
  print( f"Max growth was: {max_growth[water_id]}" )
  print( f"Avg growth is: {avg_growth[water_id]/count}" )
  set_bill_type_growth( water_id, avg_growth[water_id]/count )