Files
CCMA/src/ccma/rules/scripts/contribution_claims.py
T
Marcel PeterkauandClaude Sonnet 5 2484a1631d Add individually agreed membership fees (contribution overrides)
Members are sometimes given a fee that deviates from the regular
schedule -- e.g. a reduced rate for students -- for a specific period.
Add a per-member "Beitrag" tab where such deviations can be recorded
with a month-granular date range (Ab/Bis), a mandatory reason, and
either a fixed annual amount or a percentage discount off whichever
base rate is in effect at the time.

Data model: ContributionData gets a contribution_overrides list, each
entry validated (month format, Bis >= Ab, non-overlapping ranges per
member, reason required) and CRUD'd through the repository
(record/update/delete/get_contribution_override), consistent with how
donations already work.

Integration: contribution_claims.py now computes each membership-fee
claim's amount month by month instead of a single rate for the whole
billing period, picking up whichever override (if any) covers each
individual month. That handles an override starting or ending mid
period correctly (e.g. a semiannual payer whose discount begins in
March) without changing behavior for members without overrides.
Already-created claims are never recalculated retroactively, matching
how changes to the global contribution rates already behave.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
2026-08-15 00:57:51 +02:00

260 lines
10 KiB
Python

import calendar
from datetime import date, timedelta
from decimal import ROUND_HALF_UP, Decimal
from ccma.domain.contributions import contribution_override_covers_month
from ccma.domain.dates import DateValidationError, parse_iso_date
from ccma.rules.api import RuleContext, create_claim
from ccma.rules.scripts._shared import CONTRIBUTION_STATUSES
RULE_ID = "contribution-claims"
ORDER = 40
CENT = Decimal("0.01")
MONTH_NAMES = (
"",
"Januar",
"Februar",
"März",
"April",
"Mai",
"Juni",
"Juli",
"August",
"September",
"Oktober",
"November",
"Dezember",
)
def evaluate(context: RuleContext):
member = context.member
if member.honorary or member.status not in CONTRIBUTION_STATUSES:
return []
try:
accepted_at = parse_iso_date(member.accepted_at, "Aufnahmebeschluss")
started_at = parse_iso_date(member.membership_started_at, "Mitglied seit") or accepted_at
ended_at = parse_iso_date(member.membership_ended_at, "Austrittsdatum")
except DateValidationError:
return []
if not accepted_at or not started_at:
return []
actions = []
admission_rule = _rule_for(context.repository_config, accepted_at)
if admission_rule:
admission_fee = Decimal(str(admission_rule.get("admission_fee", "0")))
if admission_fee > 0:
due_days = int(admission_rule.get("first_payment_due_days_after_acceptance", 28))
admission_due = accepted_at + timedelta(days=due_days)
if not ended_at or admission_due <= ended_at:
actions.append(
create_claim(
rule_id=RULE_ID,
member=member,
claim_key="admission-fee",
payload={
"type": "admission_fee",
"title": "Aufnahmegebühr",
"amount": _money(admission_fee),
"due_date": admission_due.isoformat(),
"calculation": {"rule_id": admission_rule.get("rule_id", "")},
},
)
)
year_from = (
started_at.year
if getattr(context.settings, "retroactive_claims", False)
else context.today.year
)
for year in range(year_from, context.today.year + 2):
actions.extend(_membership_claims(context, started_at, accepted_at, ended_at, year))
return actions
def _membership_claims(
context: RuleContext,
started_at: date,
accepted_at: date,
ended_at: date | None,
year: int,
):
member = context.member
period_start = max(started_at, date(year, 1, 1))
if period_start.year > year:
return []
rule = _rule_for(context.repository_config, period_start)
if not rule:
return []
annual_amount = Decimal(str(rule.get("annual_amount", "0")))
issue_days = int(rule.get("issue_days_before_due", 30))
due_days_after_entry = int(rule.get("first_payment_due_days_after_acceptance", 28))
if annual_amount <= 0:
return []
if member.payment_frequency == "semiannual":
configured_due_dates = list(rule.get("semiannual_due") or ["01-31", "07-31"])
while len(configured_due_dates) < 2:
configured_due_dates.append(("01-31", "07-31")[len(configured_due_dates)])
periods = [
("first-half", 1, 6, _due_date(year, configured_due_dates[0], "01-31")),
("second-half", 7, 12, _due_date(year, configured_due_dates[1], "07-31")),
]
elif member.payment_frequency == "quarterly":
periods = [
(
f"quarter-{quarter}",
first_month,
first_month + 2,
_recurring_due_date(year, first_month, rule.get("annual_due"), "01-31"),
)
for quarter, first_month in enumerate((1, 4, 7, 10), start=1)
]
elif member.payment_frequency == "monthly":
periods = [
(
f"month-{month:02d}",
month,
month,
_recurring_due_date(year, month, rule.get("annual_due"), "01-31"),
)
for month in range(1, 13)
]
else:
periods = [("annual", 1, 12, _due_date(year, rule.get("annual_due"), "01-31"))]
actions = []
overrides = context.contributions.contribution_overrides
for suffix, first_month, last_month, regular_due in periods:
# The entry year is intentionally billed from the entry month onward,
# even when retroactive claims create old membership-fee claims.
charged_from = max(first_month, period_start.month)
months = max(0, last_month - charged_from + 1)
if months == 0:
continue
# Blended month by month rather than a single rate for the whole period, so a
# contribution override that starts or ends mid-period (e.g. a student discount
# beginning in March for a member who pays semiannually) is billed correctly.
month_amounts = [
_monthly_amount(context.repository_config, overrides, year, month)
for month in range(charged_from, last_month + 1)
]
amount = sum((value for value, _override_id in month_amounts), Decimal("0")).quantize(
CENT, rounding=ROUND_HALF_UP
)
applied_overrides = sorted({override_id for _value, override_id in month_amounts if override_id})
entry_year = started_at.year == year
issue_date = regular_due - timedelta(days=issue_days)
if not entry_year and context.today < issue_date:
continue
due_date = regular_due
if entry_year and regular_due < accepted_at + timedelta(days=due_days_after_entry):
due_date = accepted_at + timedelta(days=due_days_after_entry)
if ended_at and due_date > ended_at:
continue
claim_key = f"membership-fee:{year}:{suffix}"
full_period_months = last_month - first_month + 1
description = _title(year, suffix)
if months < full_period_months:
unit = "Monat" if months == 1 else "Monate"
description = f"{description} ({months} {unit})"
actions.append(
create_claim(
rule_id=RULE_ID,
member=member,
claim_key=claim_key,
payload={
"type": "membership_fee",
"title": _title(year, suffix),
"description": description,
"amount": _money(amount),
"due_date": due_date.isoformat(),
"service_period": {
"from": date(year, charged_from, 1).isoformat(),
"until": date(year, last_month, calendar.monthrange(year, last_month)[1]).isoformat(),
},
"calculation": {
"rule_id": rule.get("rule_id", ""),
"annual_amount": _money(annual_amount),
"months": months,
"formula": "annual_amount * months / 12",
"contribution_override_ids": applied_overrides,
},
},
)
)
return actions
def _monthly_amount(config, overrides, year: int, month: int) -> tuple[Decimal, str]:
"""Returns the effective monthly rate for a single calendar month, and the
override's id if one applied (empty string otherwise)."""
rule = _rule_for(config, date(year, month, 1))
base_annual = Decimal(str(rule.get("annual_amount", "0"))) if rule else Decimal("0")
month_key = f"{year:04d}-{month:02d}"
override = next(
(item for item in overrides if contribution_override_covers_month(item, month_key)), None
)
if override is None:
return base_annual / Decimal(12), ""
kind = str(override.get("kind", ""))
value = Decimal(str(override.get("value", "0")))
if kind == "amount":
annual = value
elif kind == "percent":
annual = base_annual * (Decimal(100) - value) / Decimal(100)
else:
annual = base_annual
return annual / Decimal(12), str(override.get("override_id", ""))
def _rule_for(config, target: date):
selected = None
for rule in config.get("contribution_rules", []):
try:
valid_from = date.fromisoformat(str(rule.get("valid_from", "")))
valid_until_raw = rule.get("valid_until")
valid_until = date.fromisoformat(str(valid_until_raw)) if valid_until_raw else None
except ValueError:
continue
if valid_from <= target and (not valid_until or target <= valid_until):
if selected is None or valid_from > selected[0]:
selected = (valid_from, rule)
return selected[1] if selected else None
def _money(value: Decimal) -> str:
return str(value.quantize(CENT, rounding=ROUND_HALF_UP))
def _due_date(year: int, value, fallback: str) -> date:
try:
month, day = (int(part) for part in str(value or fallback).split("-", 1))
return date(year, month, day)
except (TypeError, ValueError):
month, day = (int(part) for part in fallback.split("-", 1))
return date(year, month, day)
def _recurring_due_date(year: int, month: int, value, fallback: str) -> date:
try:
_configured_month, day = (int(part) for part in str(value or fallback).split("-", 1))
except (TypeError, ValueError):
day = int(fallback.split("-", 1)[1])
return date(year, month, min(day, calendar.monthrange(year, month)[1]))
def _title(year: int, suffix: str) -> str:
if suffix.startswith("month-"):
month = int(suffix.removeprefix("month-"))
return f"Mitgliedsbeitrag {MONTH_NAMES[month]} {year}"
if suffix.startswith("quarter-"):
quarter = int(suffix.removeprefix("quarter-"))
return f"Mitgliedsbeitrag {quarter}. Quartal {year}"
if suffix == "first-half":
return f"Mitgliedsbeitrag 1. Halbjahr {year}"
if suffix == "second-half":
return f"Mitgliedsbeitrag 2. Halbjahr {year}"
return f"Mitgliedsbeitrag {year}"