Bill / EnergyBreakdown / BillDerivation / sap_fuel were under
domain/property_baseline/ only because Baseline was built first. The Modelling
stage now needs them too, so move them (and their tests) to a neutral
domain/billing/ — Fuel/FuelRates already live in the shared domain/fuel_rates/.
Avoids a modelling -> property_baseline cross-stage import and a package name
that wrongly implies ownership (ADR-0011, ADR-0014 amendment). Pure git mv +
import rewrite across 10 files; 40 billing/baseline/repo tests pass, pyright
strict clean. CONTEXT.md Bill Derivation location updated.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The fuel codes the calculator now puts on SapResult are its own codes — raw
gov-API enums or already-Table-32, depending on the source mapper (ADR-0015).
sap_code_to_fuel now runs the code through table_32.to_table_32_code
(promoted from private _to_table_32_code) — T32-first, then API-translate,
the SAME normalization the calculator's pricing/CO2 helpers use — before the
Table-32 -> Fuel dispatch, so the bill's carrier matches what the calculator
billed (incl. the API/T32 collision codes, e.g. 20 = wood-logs not heat-net).
Falls back to the raw code for billing fuels the price table omits (the 41-58
heat-network range), which resolve to HEAT_NETWORK -> UnpricedFuel — stricter
than, and intentionally divergent from, the calculator's lossy
default-to-mains-gas for an unpriced code (ADR-0014 §5).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Slice 3 of Bill Derivation. sap_code_to_fuel(code) maps a SAP 10.2 / Table 32
fuel code to the canonical billing Fuel — bounded to the ~47 Table 32 codes (the
carrier, orthogonal to the PCDB product index, so all PCDB heat pumps share one
electricity code). Mains gas / LPG / oil+bioliquids / coal / smokeless / wood /
electricity (standard + off-peak) / heat-network groupings; an unmapped code
(dual fuel, grid-export) raises UnmappedSapCode rather than guessing.
Also: ADR-0014 deferred/TODO section records the stubbed appliances+cooking
(pending the SapResult fields), the off-peak day/night split, the heat-network
rate gap, and regional rates / ETL.
The SapResult -> EnergyBreakdown adapter (next slice) is gated on the
appliances/cooking fields landing on SapResult.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>