moved some hard-coded dates to top of calc.py for ease of use in multiple functions, but also just for code readability, they are more like constants than variables. Code now works out key_dates for use in dealing with future bills / next steps

TODO

@@ -1,33 +1,11 @@
 UI:
+    * use key_dates to highlight when I quit, when we own car
 
 For bills:
-    Future bills:
+    [DONE] * calc quit date based on finance data
-        * longer-term: make the moment we quit / own car trigger new bill creation, and remove hard-coded logic on costs - just use bill_data created
+    [DONE] * calc date of car lease end or buyout
-            - this will then cover handling different bill_types or growth models
+    * use this to populate bill estimates, so this allows totals / year and simplifies calc.py
 
-    * might need to be able to mark a specific bill as an outlier - so we ignore the data somehow (think Gas is messing with my bills)
+    * might need to be able to mark a specific bill as an outlier:
+        - so we ignore the data somehow (think Gas is messing with my bills)
         - and even electricity, water, etc. for when we were away in Europe but mostly gas/elec
-
-LONGER/HARDER:
-    * need to work out 'first bill' and 'last bill' to auto-fill missing bills based on
-      -- all missing bills follow varying growth models & its by choice -- therefore I need this in DB
-         - ANN: flat, min, avg, max, manual
-         - QTR: flat, qtrly seasonal: min/avg/max/manual, qtrly simple: min/avg/max/manual, annual: min/avg/max/manual
-         - MON: flat, monthly: min/avg/max/manual, annual: min/avg/max/manual
-      -- use this logic to add missing bills (date):
-           -- ANN: missing annual bill, find date based on MM-DD and add new year - given we start with first_bill anyway, will only be used for future bill predictions
-           -- QTR: missing quarterly bill, find date based on MM-DD and ??? - can have missing bilsl in first year
-           -- MON: missing monthly bills, find date based on DD and put in each missing month 
-      -- use this logic to add missing bills (amount):
-           -- ANN: future only, so add ann_growth (based on drop-down) for each future year
-           -- QTR: add growth (based on drop-down) for each future year
-           -- MON: add growth (based on drop-down) for each future year 
-
-MUCH LONGER/HARDER:
-    potentially for each bill_type, there are unique extras - e.g. THIS feels too hard:
-        water has 2 fixed charges (water & sewerage) and then a consumption charge (per ML)
-        elec has 1 fixe charge (daily) and then consumption (per kwh) BUT, also daily solar rate
-        gas has fixed charge and consumption
-        internet, kayo is monthly fixed (but can go up sometimes)
-        eweka is annual fixed
-        phone is messier again.

bills.py

@@ -291,7 +291,7 @@ def get_growth_value( bt, bill_type ):
 # and I didn't want to input 12 of them at the same price), and it always
 # occurs for future bills
 ################################################################################
-def process_bill_data(bd, bt, bf):
+def process_bill_data(bd, bt, bf, key_dates):
     # this maps a bill id to a freq id (e.g. bill #34 - has a frequency of #2 (which might be quarterly)
     bt_id_freq = {row["id"]: row["freq"] for row in bt}
     bt_id_ann_growth_avg = {row["id"]: row["ann_growth_avg"] for row in bt}
@@ -495,3 +495,4 @@ def calc_future_totals(bill_info, bill_types):
             # had to round to 2 decimal here to get sensible totals
             total[bt['id']][yr] = round( total[bt['id']][yr], 2 )
     return total
+

calc.py

@@ -5,6 +5,15 @@ from defines import END_YEAR
 # GLOBAL CONSTANTS
 LEASE = 0
 
+# Dates that don't change
+car_balloon_date = datetime(2026, 11, 15)
+new_fin_year_25 = datetime(2025, 7, 1)
+new_fin_year_26 = datetime(2026, 7, 1)
+end_date = datetime(END_YEAR, 4, 15)
+school_fees_date = datetime(2025, 12, 5)
+mich_present_date = datetime(2026,10,15)
+first_pay_date = datetime(2025,1,8)
+
 def bill_amount_today(finance, day, bill_data, bt_id_name, total ):
     amt=0
     day_str = day.strftime("%Y-%m-%d")
@@ -100,8 +109,6 @@ def calculate_savings_depletion(finance, bill_data, bill_type):
     D_has_quit = False
     D_quit_year = 0
     claim_tax_on_leave = False
-    new_fin_year_25 = datetime(2025, 7, 1)
-    new_fin_year_26 = datetime(2026, 7, 1)
 
     # Constants for interest calculations
     annual_interest_rate = Interest_Rate / 100.0
@@ -109,7 +116,6 @@ def calculate_savings_depletion(finance, bill_data, bill_type):
 
     # main loop range -- start from now, and simulate till D is 60 (April 2031)
     current_date = datetime.today()
-    end_date = datetime(END_YEAR, 4, 15)
 
     # work out which bill_types relate to future bills
     for bt in bill_type:
@@ -151,11 +157,6 @@ def calculate_savings_depletion(finance, bill_data, bill_type):
     depletion_date = None
     savings_per_fortnight = []
     
-    # significant dates that are non-changeable
-    school_fees_date = datetime(2025, 12, 5)
-    car_balloon_date = datetime(2026, 11, 15)
-    mich_present_date = datetime(2026,10,15)
-
     # significant dates - but who knows when? :)
     overseas_trip_date = datetime.strptime( finance['Overseas_trip_date'], "%Y-%m-%d")
     mark_reno_date = datetime.strptime( finance['Mark_reno_date'], "%Y-%m-%d")
@@ -360,3 +361,26 @@ def calculate_savings_depletion(finance, bill_data, bill_type):
 
     return depletion_date, savings_per_fortnight, current_savings
 
+################################################################################
+# work out the date D quits and when we own the car, so we can then use it to
+# handle future bills
+################################################################################
+def calc_key_dates( finance ):
+    key_dates={}
+    now = datetime.today()
+    # this will be 0 to 13 days - how far into this fortnights pay cycle are we now
+    days_in_pay_fortnight= ( now - first_pay_date ).days % 14
+
+    # add 1 less fortnight than we continue to work, then add rest of pay cycle (14-days_in_pay_fortnight)
+    key_dates['D_quit_date'] = (now+timedelta(weeks=2*(finance['D_Num_fortnights_pay']-1))+timedelta(days=(14-days_in_pay_fortnight))).strftime('%Y-%m-%d')
+
+    # use lease date
+    if finance['Ioniq6_future'] == LEASE:
+        key_dates['D_hyundai_owned'] = car_balloon_date.strftime('%Y-%m-%d')
+    # use buyout date
+    else:
+        key_dates['D_hyundai_owned'] = finance['Car_buyout_date']
+
+    print( f"kd={key_dates}" )
+    return key_dates
+

main.py

@@ -1,6 +1,6 @@
 # main.py
 from flask import Flask, render_template, request, redirect, url_for, Response, jsonify
-from calc import calculate_savings_depletion
+from calc import calculate_savings_depletion, calc_key_dates
 from db import init_db, get_finance_data, update_finance, get_budget_data, insert_cset, get_comp_set_data, get_comp_set_options, get_bill_freqs
 from db import get_bill_data, new_bill, update_bill_data, delete_bill
 from db import get_bill_ui, save_ui
@@ -145,14 +145,20 @@ def update():
 
 @app.route('/bills')
 def DisplayBillData():
+    finance_data = get_finance_data()
+    # work out when D quits, when car is owned
+    key_dates = calc_key_dates( finance_data )
     bill_data = get_bill_data("order_by_bill_type_then_date")
     bill_types = get_bill_types()
     bill_freqs = get_bill_freqs()
     bill_ui = get_bill_ui()
-    bill_info=process_bill_data(bill_data, bill_types, bill_freqs)
+    # take bill data, AND work out estimated future bills - process this into the bill_info array, 
+    bill_info=process_bill_data(bill_data, bill_types, bill_freqs, key_dates)
+    # get an array of the total costs of bills each year - purely cosmetic (using bill_info)
     total=calc_future_totals(bill_info, bill_types)
+    # update/re-get bill_data now that new estimated bills have been added
     bill_data = get_bill_data("order_by_bill_type_then_date")
-    return render_template('bills.html', bill_data=bill_data, bill_types=bill_types, bill_freqs=bill_freqs, bill_ui=bill_ui, this_year=datetime.today().year, END_YEAR=END_YEAR, total=total )
+    return render_template('bills.html', bill_data=bill_data, bill_types=bill_types, bill_freqs=bill_freqs, bill_ui=bill_ui, this_year=datetime.today().year, END_YEAR=END_YEAR, total=total, key_dates=key_dates )
 
 @app.route('/newbilltype', methods=['POST'])
 def InsertBillType():

templates/index.html

@@ -152,7 +152,7 @@
       </div>
     </div>
     </form>
-    <div class="row mt-4 highcharts-dark" id="container" style="width:100%; height:400px;"></div>   
+    <div class="row mt-4 highcharts-dark" id="container" style="width:100%; height:800px;"></div>
     <script type="text/javascript">
         // make these global so we can also use them in the /save route (via modal)
         const savingsData = JSON.parse('{{ savings | tojson }}');