diff --git a/frontend/src/lib/concept-api.ts b/frontend/src/lib/concept-api.ts
index f6ad7a2f..f0d1cb1c 100644
--- a/frontend/src/lib/concept-api.ts
+++ b/frontend/src/lib/concept-api.ts
@@ -122,9 +122,7 @@ export interface FinancialModel {
}
export type PriceSource =
- | "objective_district_median"
- | "district_reference"
- | "class_norm";
+ "objective_district_median" | "district_reference" | "class_norm";
export interface ConceptVariant {
strategy: ConceptStrategy;
@@ -198,6 +196,61 @@ export function useCreateConcept() {
});
}
+// ── Live recompute contract (Stage 2b, #1965) ───────────────────────────────
+
+/**
+ * MassingProgram — the aggregated building program POSTed to
+ * `/api/v1/concepts/recompute`. Mirrors `backend/app/schemas/concept.py`
+ * (and `components["schemas"]["MassingProgram"]` in api-types.ts): an already
+ * FOLDED program from the interactive 3D massing's `computeModel`
+ * (Σ footprint × floors), без покомпонентной геометрии секций. The endpoint
+ * synthesises ТЭП from it and runs the same `compute_financial` → live economics.
+ */
+export interface MassingProgram {
+ /** Суммарное пятно застройки всех секций, кв.м (скаляр). */
+ total_footprint_sqm: number;
+ /** Этажность программы. */
+ floors: number;
+ /** Число секций (метаданные программы). */
+ sections: number;
+ /** Площадь участка для плотности (FAR). */
+ site_area_sqm: number;
+ housing_class: HousingClass;
+ development_type: DevelopmentType;
+ /** Стоимость участка для финмодели (опционально). */
+ land_cost_rub?: number | null;
+ /** Предрезолвленная рыночная цена жилья, ₽/м² (skip backend DB lookup). */
+ market_price_per_sqm?: number | null;
+ /** Подлинный источник предрезолвленной цены (forward из financial_estimate). */
+ price_source?: string | null;
+ /** WKT-точка центроида участка (WGS84) для DB-резолва цены при fallback. */
+ parcel_centroid_wkt?: string | null;
+}
+
+/** Output of `/api/v1/concepts/recompute`: synthesised ТЭП + finmodel. */
+export interface MassingRecomputeOutput {
+ teap: Teap;
+ financial: FinancialModel;
+}
+
+/**
+ * POST /api/v1/concepts/recompute — live financial recompute for an interactive
+ * massing program. Action (slider-driven) → `useMutation` per the data-layer
+ * rule; uses the shared `apiFetch` (base URL + session header + Content-Type).
+ *
+ * Stage 2b drives this off the 3D MassingScene's `onModelChange` (debounced),
+ * with latest-wins sequencing handled by the caller (see MassingEconomics).
+ */
+export function useRecomputeMassing() {
+ return useMutation({
+ mutationFn: (payload) =>
+ apiFetch("/api/v1/concepts/recompute", {
+ method: "POST",
+ body: JSON.stringify(payload),
+ }),
+ });
+}
+
// ── Hook: useCadastreGeom ─────────────────────────────────────────────────────
/**
@@ -280,3 +333,28 @@ export function polygonAreaSqm(polygon: Polygon): number {
}
return Math.abs((area * R * R) / 2);
}
+
+/**
+ * Centroid of a WGS84 polygon's outer ring as a WKT `POINT(lon lat)` string —
+ * used as `parcel_centroid_wkt` so the recompute endpoint can DB-resolve a
+ * market price when no pre-resolved one is forwarded. Simple ring-average
+ * (good enough as a point hint; not a true area centroid). Returns null on a
+ * degenerate ring.
+ */
+export function polygonCentroidWkt(polygon: Polygon): string | null {
+ const ring = polygon.coordinates[0];
+ if (!ring || ring.length < 4) return null;
+ // Skip the closing vertex (== first) when averaging.
+ const pts = ring.slice(0, ring.length - 1);
+ if (pts.length === 0) return null;
+ let sumLon = 0;
+ let sumLat = 0;
+ for (const [lon, lat] of pts) {
+ sumLon += lon;
+ sumLat += lat;
+ }
+ const lon = sumLon / pts.length;
+ const lat = sumLat / pts.length;
+ if (!Number.isFinite(lon) || !Number.isFinite(lat)) return null;
+ return `POINT(${lon} ${lat})`;
+}