Allow customising ticketing fee calculation

Existing ticketing fees can be preserved at database migration time

selfserv/settings.example.py

@@ -1,5 +1,6 @@
 #	Society Self-Service
-#	Copyright © 2018-2019  Yingtong Li (RunasSudo)
+#	Copyright © 2018-2023  Yingtong Li (RunasSudo)
+#	Copyright © 2023  MUMUS Inc.
 #
 #	This program is free software: you can redistribute it and/or modify
 #	it under the terms of the GNU Affero General Public License as published by
@@ -32,6 +33,9 @@ PROMO_LOGO_URL = 'https://placehold.it/2000x500'
 PROMO_LOGO_LINK = 'https://example.com'
 PROMO_GROUPS_MANDATORY = ['All Years']
 
+TICKETING_FEE_PROPORTION = 0.0175  # Previous default was (1-1/1.01884)
+TICKETING_FEE_FIXED = 0.30  # Previous default was 0.8133/1.01884
+
 ABA_USER_NAME = 'Society Name'
 ABA_BANK_NAME = 'CBA'
 ABA_BANK_CODE = 0

sstreasury/jinja2/sstreasury/budget_edit.html

@@ -225,9 +225,12 @@
 			}
 		});
 		
+		const ticketingFeeProportion = {{ settings.TICKETING_FEE_PROPORTION }};
+		const ticketingFeeFixed = {{ settings.TICKETING_FEE_FIXED }};
+		const editing = true;
+		
 		var revenue_data = JSON.parse({{ import('json').dumps(import('json').dumps(revision.revenue))|safe }});
 		var expense_data = JSON.parse({{ import('json').dumps(import('json').dumps(revision.expense))|safe }});
-		var editing = true;
 		makeGrid();
 		
 		dragula([document.querySelector('#revenue_grid tbody')], {

sstreasury/jinja2/sstreasury/budget_view.html

@@ -385,9 +385,13 @@
 	<script src="{{ static('sstreasury/budget.js') }}"></script>
 	
 	<script>
+		const ticketingFeeProportion = {{ revision.ticketing_fee_proportion }};
+		const ticketingFeeFixed = {{ revision.ticketing_fee_fixed }};
+		const editing = false;
+		
 		var revenue_data = JSON.parse({{ import('json').dumps(import('json').dumps(revision.revenue))|safe }});
 		var expense_data = JSON.parse({{ import('json').dumps(import('json').dumps(revision.expense))|safe }});
-		var editing = false;
+		
 		makeGrid();
 		makeCharts();
 	</script>

sstreasury/models.py

@@ -1,5 +1,6 @@
 #    Society Self-Service
-#    Copyright © 2018–2022  Yingtong Li (RunasSudo)
+#    Copyright © 2018–2023  Yingtong Li (RunasSudo)
+#    Copyright © 2023  MUMUS Inc.
 #
 #    This program is free software: you can redistribute it and/or modify
 #    it under the terms of the GNU Affero General Public License as published by
@@ -78,6 +79,9 @@ class BudgetRevision(models.Model):
 	expense_no_emergency_fund = models.BooleanField()
 	expense_comments = models.TextField()
 	
+	ticketing_fee_proportion = models.FloatField()
+	ticketing_fee_fixed = models.FloatField()
+	
 	action = models.IntegerField(choices=[(v.value, v.description) for v in BudgetAction])
 	
 	class Meta:
@@ -103,7 +107,7 @@ class BudgetRevision(models.Model):
 			try:
 				total += Decimal(item['Unit price']) * Decimal(item['Units'])
 				if item['IWT'] and item['Unit price'] > 0:
-					total -= (Decimal(item['Unit price']) - (Decimal(item['Unit price']) - Decimal('0.8133')) / Decimal('1.01884')) * item['Units']
+					total -= (Decimal(item['Unit price']) * Decimal(self.ticketing_fee_proportion) + Decimal(self.ticketing_fee_fixed)) * item['Units']
 			except TypeError:
 				# Invalid unit price, etc.
 				pass

sstreasury/static/sstreasury/budget.js

@@ -30,7 +30,7 @@ function recalcRevTotal(args) {
 	for (var row of args.grid.data) {
 		revTotal += row['Unit price'] * row['Units'];
 		if (row['Unit price'] > 0 && row['IWT']) {
-			revTotalIWT += (row['Unit price'] - (row['Unit price'] - 0.8133) / 1.01884) * row['Units'];
+			revTotalIWT += (row['Unit price'] * ticketingFeeProportion + ticketingFeeFixed) * row['Units'];
 		}
 	}
 	
@@ -38,7 +38,7 @@ function recalcRevTotal(args) {
 	
 	if (revTotalIWT > 0) {
 		var totalrow = $('<tr class="jsgrid-row totalrow" style="font-style: italic;"></tr>');
-		totalrow.append($('<td class="jsgrid-cell">Less IWT fees:</td>').prop('colspan', args.grid.fields.length - (editing ? 2 : 1)));
+		totalrow.append($('<td class="jsgrid-cell">Less ticketing fees:</td>').prop('colspan', args.grid.fields.length - (editing ? 2 : 1)));
 		totalrow.append($('<td class="jsgrid-cell jsgrid-align-right"></td>').text('($' + revTotalIWT.toFixed(2) + ')'));
 		if (editing) {
 			totalrow.append($('<td class="jsgrid-cell"></td>'));

sstreasury/views.py

@@ -296,6 +296,8 @@ def budget_new(request):
 				revision = models.BudgetRevision()
 				revision.author = request.user
 				revision.time = timezone.now()
+				revision.ticketing_fee_proportion = settings.TICKETING_FEE_PROPORTION
+				revision.ticketing_fee_fixed = settings.TICKETING_FEE_FIXED
 				revision.action = models.BudgetAction.CREATE.value
 				revision.state = models.BudgetState.DRAFT.value
 				revision = revision_from_form(budget, revision, request.POST)
@@ -335,6 +337,8 @@ def budget_edit(request, budget, revision):
 				new_revision = models.BudgetRevision()
 				new_revision.author = request.user
 				new_revision.time = timezone.now()
+				new_revision.ticketing_fee_proportion = settings.TICKETING_FEE_PROPORTION
+				new_revision.ticketing_fee_fixed = settings.TICKETING_FEE_FIXED
 				new_revision.action = models.BudgetAction.EDIT.value
 				new_revision.state = revision.state
 				new_revision = revision_from_form(budget, new_revision, request.POST)