ui/phase-15: planet inspector production controls + order-draft collapse

Adds the second end-to-end command (`setProductionType`) with a
collapse-by-`planetNumber` rule on the order draft, the segmented
production-controls component on the planet inspector, the FBS
encoder/decoder pair for `CommandPlanetProduce`, and the
`localShipClass` projection on `GameReport`. Forecast number is
deferred and tracked in the new `ui/docs/calc-bridge.md`.

ui/frontend/src/api/game-state.ts

@@ -15,6 +15,11 @@
 // rename in the local draft swaps the planet name on the rendered
 // report so the player sees their intent reflected immediately,
 // without waiting for the next turn cutoff.
+//
+// Phase 15 extends the projection with a minimal `localShipClass`
+// summary so the planet inspector's Build-Ship sub-picker has data
+// to render. Phase 17 (ship-class CRUD) widens `ShipClassSummary`
+// when the designer ships need the full attribute set.
 
 import { Builder, ByteBuffer } from "flatbuffers";
 
@@ -24,7 +29,11 @@ import {
 	GameReportRequest,
 	Report,
 } from "../proto/galaxy/fbs/report";
-import type { CommandStatus, OrderCommand } from "../sync/order-types";
+import type {
+	CommandStatus,
+	OrderCommand,
+	ProductionType,
+} from "../sync/order-types";
 
 const MESSAGE_TYPE = "user.games.report";
 
@@ -61,6 +70,18 @@ export interface ReportPlanet {
 	freeIndustry: number | null;
 }
 
+/**
+ * ShipClassSummary is the slim projection of `report.ShipClass` the
+ * planet inspector's Build-Ship sub-picker needs in Phase 15. Only
+ * the human-visible `name` is carried — the engine command shape
+ * (`CommandPlanetProduce.subject`) takes the class name, not its
+ * underlying tech values. Phase 17 widens this type when the ship
+ * designer needs the full attribute set.
+ */
+export interface ShipClassSummary {
+	name: string;
+}
+
 export interface GameReport {
 	turn: number;
 	mapWidth: number;
@@ -73,6 +94,14 @@ export interface GameReport {
 	 * has not produced a report yet (boot state).
 	 */
 	race: string;
+	/**
+	 * localShipClass enumerates the player's own designed ship classes
+	 * by name. Empty until at least one class is created
+	 * (`CommandShipClassCreate`, Phase 17). The Build-Ship sub-picker
+	 * shows a localized "no ship classes" placeholder when this is
+	 * empty.
+	 */
+	localShipClass: ShipClassSummary[];
 }
 
 export async function fetchGameReport(
@@ -189,6 +218,13 @@ function decodeReport(report: Report): GameReport {
 		});
 	}
 
+	const localShipClass: ShipClassSummary[] = [];
+	for (let i = 0; i < report.localShipClassLength(); i++) {
+		const sc = report.localShipClass(i);
+		if (sc === null) continue;
+		localShipClass.push({ name: sc.name() ?? "" });
+	}
+
 	return {
 		turn: Number(report.turn()),
 		mapWidth: report.width(),
@@ -196,6 +232,7 @@ function decodeReport(report: Report): GameReport {
 		planetCount: report.planetCount(),
 		planets,
 		race: report.race() ?? "",
+		localShipClass,
 	};
 }
 
@@ -221,10 +258,12 @@ export function uuidToHiLo(value: string): [bigint, bigint] {
 /**
  * applyOrderOverlay returns a copy of `report` with every locally-
  * valid or still-in-flight or applied command from `commands`
- * projected on top. Phase 14 understands `planetRename` only —
- * every other variant passes through. The function is pure:
- * callers re-derive the overlay whenever the draft or the report
- * change.
+ * projected on top. Phase 14 introduced the overlay for
+ * `planetRename`; Phase 15 extends it to `setProductionType` so the
+ * inspector segment / map label reflect the chosen production target
+ * before the engine confirms it. Other variants pass through. The
+ * function is pure: callers re-derive the overlay whenever the draft
+ * or the report change.
  *
  * `statuses` maps command id → status. Entries with `valid`,
  * `submitting`, or `applied` participate in the overlay — together
@@ -250,18 +289,69 @@ export function applyOrderOverlay(
 		) {
 			continue;
 		}
-		if (cmd.kind !== "planetRename") continue;
-		const idx = report.planets.findIndex((p) => p.number === cmd.planetNumber);
-		if (idx < 0) continue;
-		if (mutatedPlanets === null) {
-			mutatedPlanets = [...report.planets];
+		if (cmd.kind === "planetRename") {
+			const idx = report.planets.findIndex(
+				(p) => p.number === cmd.planetNumber,
+			);
+			if (idx < 0) continue;
+			if (mutatedPlanets === null) {
+				mutatedPlanets = [...report.planets];
+			}
+			mutatedPlanets[idx] = { ...mutatedPlanets[idx]!, name: cmd.name };
+			continue;
+		}
+		if (cmd.kind === "setProductionType") {
+			const idx = report.planets.findIndex(
+				(p) => p.number === cmd.planetNumber,
+			);
+			if (idx < 0) continue;
+			if (mutatedPlanets === null) {
+				mutatedPlanets = [...report.planets];
+			}
+			mutatedPlanets[idx] = {
+				...mutatedPlanets[idx]!,
+				production: productionDisplayFromCommand(
+					cmd.productionType,
+					cmd.subject,
+				),
+			};
+			continue;
 		}
-		mutatedPlanets[idx] = { ...mutatedPlanets[idx]!, name: cmd.name };
 	}
 	if (mutatedPlanets === null) return report;
 	return { ...report, planets: mutatedPlanets };
 }
 
+/**
+ * productionDisplayFromCommand mirrors the engine's
+ * `Cache.PlanetProductionDisplayName`
+ * (`game/internal/controller/planet.go`) for the optimistic overlay.
+ * Keeping the strings byte-equal with the next server report avoids
+ * a flicker when the overlay drops on the next turn cutoff.
+ */
+export function productionDisplayFromCommand(
+	productionType: ProductionType,
+	subject: string,
+): string {
+	switch (productionType) {
+		case "MAT":
+			return "Material";
+		case "CAP":
+			return "Capital";
+		case "DRIVE":
+			return "Drive";
+		case "WEAPONS":
+			return "Weapons";
+		case "SHIELDS":
+			return "Shields";
+		case "CARGO":
+			return "Cargo";
+		case "SCIENCE":
+		case "SHIP":
+			return subject;
+	}
+}
+
 function decodeErrorMessage(payload: Uint8Array): { code: string; message: string } {
 	if (payload.length === 0) {
 		return { code: "internal_error", message: "empty error payload" };

ui/frontend/src/lib/i18n/locales/en.ts

@@ -132,6 +132,7 @@ const en = {
 	"game.sidebar.order.status.rejected": "rejected",
 	"game.sidebar.order.label.placeholder": "{label}",
 	"game.sidebar.order.label.planet_rename": "rename planet {planet} → {name}",
+	"game.sidebar.order.label.planet_production": "set production on planet {planet} → {target}",
 	"game.bottom_tabs.map": "map",
 	"game.bottom_tabs.calc": "calc",
 	"game.bottom_tabs.order": "order",
@@ -167,6 +168,16 @@ const en = {
 	"game.inspector.planet.rename.invalid.consecutive_specials": "too many special characters in a row",
 	"game.inspector.planet.rename.invalid.whitespace": "name cannot contain spaces",
 	"game.inspector.planet.rename.invalid.disallowed_character": "name contains disallowed characters",
+	"game.inspector.planet.production.title": "production",
+	"game.inspector.planet.production.option.industry": "industry",
+	"game.inspector.planet.production.option.materials": "materials",
+	"game.inspector.planet.production.option.research": "research",
+	"game.inspector.planet.production.option.ship": "build ship",
+	"game.inspector.planet.production.research.drive": "drive",
+	"game.inspector.planet.production.research.weapons": "weapons",
+	"game.inspector.planet.production.research.shields": "shields",
+	"game.inspector.planet.production.research.cargo": "cargo",
+	"game.inspector.planet.production.ship.no_classes": "no ship classes designed yet",
 } as const;
 
 export default en;

ui/frontend/src/lib/i18n/locales/ru.ts

@@ -133,6 +133,7 @@ const ru: Record<keyof typeof en, string> = {
 	"game.sidebar.order.status.rejected": "отклонена",
 	"game.sidebar.order.label.placeholder": "{label}",
 	"game.sidebar.order.label.planet_rename": "переименовать планету {planet} → {name}",
+	"game.sidebar.order.label.planet_production": "сменить производство планеты {planet} → {target}",
 	"game.bottom_tabs.map": "карта",
 	"game.bottom_tabs.calc": "калк",
 	"game.bottom_tabs.order": "приказ",
@@ -168,6 +169,16 @@ const ru: Record<keyof typeof en, string> = {
 	"game.inspector.planet.rename.invalid.consecutive_specials": "слишком много спецсимволов подряд",
 	"game.inspector.planet.rename.invalid.whitespace": "имя не может содержать пробелы",
 	"game.inspector.planet.rename.invalid.disallowed_character": "имя содержит недопустимые символы",
+	"game.inspector.planet.production.title": "производство",
+	"game.inspector.planet.production.option.industry": "промышленность",
+	"game.inspector.planet.production.option.materials": "сырьё",
+	"game.inspector.planet.production.option.research": "исследование",
+	"game.inspector.planet.production.option.ship": "корабль",
+	"game.inspector.planet.production.research.drive": "двигатель",
+	"game.inspector.planet.production.research.weapons": "оружие",
+	"game.inspector.planet.production.research.shields": "щиты",
+	"game.inspector.planet.production.research.cargo": "трюм",
+	"game.inspector.planet.production.ship.no_classes": "классы кораблей ещё не спроектированы",
 };
 
 export default ru;

ui/frontend/src/lib/inspectors/planet-sheet.svelte

@@ -11,16 +11,20 @@ that clears the selection. Swipe-to-dismiss and tap-outside-to-
 dismiss from the IA section §6 land in Phase 35 polish.
 -->
 <script lang="ts">
-	import type { ReportPlanet } from "../../api/game-state";
+	import type {
+		ReportPlanet,
+		ShipClassSummary,
+	} from "../../api/game-state";
 	import { i18n } from "$lib/i18n/index.svelte";
 	import Planet from "./planet.svelte";
 
 	type Props = {
 		planet: ReportPlanet | null;
+		localShipClass: ShipClassSummary[];
 		onMap: boolean;
 		onClose: () => void;
 	};
-	let { planet, onMap, onClose }: Props = $props();
+	let { planet, localShipClass, onMap, onClose }: Props = $props();
 </script>
 
 {#if planet !== null && onMap}
@@ -38,7 +42,7 @@ dismiss from the IA section §6 land in Phase 35 polish.
 		>
 			✕
 		</button>
-		<Planet {planet} />
+		<Planet {planet} {localShipClass} />
 	</section>
 {/if}
 

ui/frontend/src/lib/inspectors/planet.svelte

@@ -14,7 +14,10 @@ field with five buttons.
 -->
 <script lang="ts">
 	import { getContext, tick } from "svelte";
-	import type { ReportPlanet } from "../../api/game-state";
+	import type {
+		ReportPlanet,
+		ShipClassSummary,
+	} from "../../api/game-state";
 	import { i18n, type TranslationKey } from "$lib/i18n/index.svelte";
 	import {
 		ORDER_DRAFT_CONTEXT_KEY,
@@ -24,11 +27,13 @@ field with five buttons.
 		validateEntityName,
 		type EntityNameInvalidReason,
 	} from "$lib/util/entity-name";
+	import Production from "./planet/production.svelte";
 
 	type Props = {
 		planet: ReportPlanet;
+		localShipClass: ShipClassSummary[];
 	};
-	let { planet }: Props = $props();
+	let { planet, localShipClass }: Props = $props();
 
 	const kindKeyMap: Record<ReportPlanet["kind"], TranslationKey> = {
 		local: "game.inspector.planet.kind.local",
@@ -191,6 +196,10 @@ field with five buttons.
 		</div>
 	{/if}
 
+	{#if planet.kind === "local"}
+		<Production {planet} {localShipClass} />
+	{/if}
+
 	<dl class="fields">
 		{#if planet.kind === "other" && planet.owner !== null}
 			<div class="field" data-testid="inspector-planet-field-owner">
@@ -253,7 +262,7 @@ field with five buttons.
 			</div>
 		{/if}
 
-		{#if planet.production !== null}
+		{#if planet.production !== null && planet.kind !== "local"}
 			<div class="field" data-testid="inspector-planet-field-production">
 				<dt>{i18n.t("game.inspector.planet.field.production")}</dt>
 				<dd>{productionLabel}</dd>

ui/frontend/src/lib/inspectors/planet/production.svelte

@@ -0,0 +1,317 @@
+<!--
+Phase 15 production-controls subsection of the planet inspector.
+Renders four main segments — industry / materials / research / build
+ship — and reveals a sub-row when the player picks a category that
+needs a target (research → tech field, build ship → designed class).
+Every leaf click appends a `setProductionType` command to the local
+order draft via `OrderDraftStore`; the collapse-by-`planetNumber`
+rule inside `add` keeps at most one production choice per planet.
+
+The currently-active segment is derived from `planet.production`
+through a parser that mirrors the engine's
+`Cache.PlanetProductionDisplayName` mapping. While the player is
+mid-navigation (e.g. clicked Research but has not picked a tech yet)
+a transient `expandedMain` override widens the visible state so the
+sub-row can appear without forcing the player to commit a choice
+first; the override resets whenever the inspector switches to a
+different planet or after any leaf click.
+
+Phase 15 deliberately defers the per-type forecast number — see
+`ui/docs/calc-bridge.md` for the gap analysis. The component does
+not render forecast text; the existing `freeIndustry` ("free
+production") row in the parent inspector is unchanged.
+-->
+<script lang="ts">
+	import { getContext } from "svelte";
+	import type {
+		ReportPlanet,
+		ShipClassSummary,
+	} from "../../../api/game-state";
+	import { i18n, type TranslationKey } from "$lib/i18n/index.svelte";
+	import {
+		ORDER_DRAFT_CONTEXT_KEY,
+		OrderDraftStore,
+	} from "../../../sync/order-draft.svelte";
+	import type { ProductionType } from "../../../sync/order-types";
+
+	type Props = {
+		planet: ReportPlanet;
+		localShipClass: ShipClassSummary[];
+	};
+	let { planet, localShipClass }: Props = $props();
+
+	type MainSegment = "industry" | "materials" | "research" | "ship";
+
+	const draft = getContext<OrderDraftStore | undefined>(
+		ORDER_DRAFT_CONTEXT_KEY,
+	);
+	const disabled = draft === undefined;
+
+	let expandedMain: MainSegment | null = $state(null);
+
+	const parsedMain = $derived(parseMain(planet.production, localShipClass));
+	const selectedMain = $derived(expandedMain ?? parsedMain);
+	const activeResearch = $derived(parseResearch(planet.production));
+	const activeShip = $derived(parseShip(planet.production, localShipClass));
+
+	$effect(() => {
+		// Reset the expand-override whenever the inspector switches to a
+		// different planet so a stale category does not leak across the
+		// selection boundary.
+		void planet.number;
+		expandedMain = null;
+	});
+
+	const RESEARCH_OPTIONS: ReadonlyArray<{
+		fbs: ProductionType;
+		slug: "drive" | "weapons" | "shields" | "cargo";
+		labelKey: TranslationKey;
+	}> = [
+		{
+			fbs: "DRIVE",
+			slug: "drive",
+			labelKey: "game.inspector.planet.production.research.drive",
+		},
+		{
+			fbs: "WEAPONS",
+			slug: "weapons",
+			labelKey: "game.inspector.planet.production.research.weapons",
+		},
+		{
+			fbs: "SHIELDS",
+			slug: "shields",
+			labelKey: "game.inspector.planet.production.research.shields",
+		},
+		{
+			fbs: "CARGO",
+			slug: "cargo",
+			labelKey: "game.inspector.planet.production.research.cargo",
+		},
+	];
+
+	function parseMain(
+		value: string | null,
+		classes: ShipClassSummary[],
+	): MainSegment | null {
+		if (value === null || value === "" || value === "-") return null;
+		switch (value) {
+			case "Capital":
+				return "industry";
+			case "Material":
+				return "materials";
+			case "Drive":
+			case "Weapons":
+			case "Shields":
+			case "Cargo":
+				return "research";
+		}
+		return classes.some((c) => c.name === value) ? "ship" : null;
+	}
+
+	function parseResearch(value: string | null): ProductionType | null {
+		switch (value) {
+			case "Drive":
+				return "DRIVE";
+			case "Weapons":
+				return "WEAPONS";
+			case "Shields":
+				return "SHIELDS";
+			case "Cargo":
+				return "CARGO";
+			default:
+				return null;
+		}
+	}
+
+	function parseShip(
+		value: string | null,
+		classes: ShipClassSummary[],
+	): string | null {
+		if (value === null || value === "") return null;
+		return classes.some((c) => c.name === value) ? value : null;
+	}
+
+	function clickMain(segment: MainSegment): void {
+		if (segment === "industry") {
+			void emit("CAP", "");
+			expandedMain = null;
+			return;
+		}
+		if (segment === "materials") {
+			void emit("MAT", "");
+			expandedMain = null;
+			return;
+		}
+		expandedMain = segment;
+	}
+
+	function clickResearch(value: ProductionType): void {
+		void emit(value, "");
+		expandedMain = null;
+	}
+
+	function clickShip(name: string): void {
+		void emit("SHIP", name);
+		expandedMain = null;
+	}
+
+	async function emit(
+		productionType: ProductionType,
+		subject: string,
+	): Promise<void> {
+		if (draft === undefined) return;
+		await draft.add({
+			kind: "setProductionType",
+			id: crypto.randomUUID(),
+			planetNumber: planet.number,
+			productionType,
+			subject,
+		});
+	}
+</script>
+
+<section class="production" data-testid="inspector-planet-production">
+	<h4 class="title">
+		{i18n.t("game.inspector.planet.production.title")}
+	</h4>
+	<div class="row main">
+		<button
+			type="button"
+			class="seg"
+			class:active={selectedMain === "industry"}
+			data-testid="inspector-planet-production-segment-industry"
+			disabled={disabled}
+			onclick={() => clickMain("industry")}
+		>
+			{i18n.t("game.inspector.planet.production.option.industry")}
+		</button>
+		<button
+			type="button"
+			class="seg"
+			class:active={selectedMain === "materials"}
+			data-testid="inspector-planet-production-segment-materials"
+			disabled={disabled}
+			onclick={() => clickMain("materials")}
+		>
+			{i18n.t("game.inspector.planet.production.option.materials")}
+		</button>
+		<button
+			type="button"
+			class="seg"
+			class:active={selectedMain === "research"}
+			data-testid="inspector-planet-production-segment-research"
+			disabled={disabled}
+			onclick={() => clickMain("research")}
+		>
+			{i18n.t("game.inspector.planet.production.option.research")}
+		</button>
+		<button
+			type="button"
+			class="seg"
+			class:active={selectedMain === "ship"}
+			data-testid="inspector-planet-production-segment-ship"
+			disabled={disabled}
+			onclick={() => clickMain("ship")}
+		>
+			{i18n.t("game.inspector.planet.production.option.ship")}
+		</button>
+	</div>
+
+	{#if selectedMain === "research"}
+		<div class="row sub" data-testid="inspector-planet-production-research-row">
+			{#each RESEARCH_OPTIONS as option (option.fbs)}
+				<button
+					type="button"
+					class="sub-seg"
+					class:active={activeResearch === option.fbs}
+					data-testid={`inspector-planet-production-research-${option.slug}`}
+					disabled={disabled}
+					onclick={() => clickResearch(option.fbs)}
+				>
+					{i18n.t(option.labelKey)}
+				</button>
+			{/each}
+		</div>
+	{/if}
+
+	{#if selectedMain === "ship"}
+		<div class="row sub" data-testid="inspector-planet-production-ship-row">
+			{#if localShipClass.length === 0}
+				<p
+					class="empty"
+					data-testid="inspector-planet-production-ship-empty"
+				>
+					{i18n.t("game.inspector.planet.production.ship.no_classes")}
+				</p>
+			{:else}
+				{#each localShipClass as cls (cls.name)}
+					<button
+						type="button"
+						class="sub-seg"
+						class:active={activeShip === cls.name}
+						data-testid={`inspector-planet-production-ship-${cls.name}`}
+						disabled={disabled}
+						onclick={() => clickShip(cls.name)}
+					>
+						{cls.name}
+					</button>
+				{/each}
+			{/if}
+		</div>
+	{/if}
+</section>
+
+<style>
+	.production {
+		display: flex;
+		flex-direction: column;
+		gap: 0.4rem;
+	}
+	.title {
+		margin: 0;
+		font-size: 0.85rem;
+		color: #aab;
+		font-weight: 500;
+	}
+	.row {
+		display: flex;
+		gap: 0.3rem;
+		flex-wrap: wrap;
+	}
+	.row.sub {
+		padding-left: 0.6rem;
+	}
+	.seg,
+	.sub-seg {
+		font: inherit;
+		font-size: 0.85rem;
+		padding: 0.25rem 0.55rem;
+		background: transparent;
+		color: #aab;
+		border: 1px solid #2a3150;
+		border-radius: 3px;
+		cursor: pointer;
+	}
+	.seg:not(:disabled):hover,
+	.sub-seg:not(:disabled):hover {
+		color: #e8eaf6;
+		border-color: #6d8cff;
+	}
+	.seg.active,
+	.sub-seg.active {
+		color: #e8eaf6;
+		border-color: #6d8cff;
+		background: rgba(109, 140, 255, 0.15);
+	}
+	.seg:disabled,
+	.sub-seg:disabled {
+		cursor: not-allowed;
+		opacity: 0.5;
+	}
+	.empty {
+		margin: 0;
+		font-size: 0.8rem;
+		color: #888;
+		font-style: italic;
+	}
+</style>

ui/frontend/src/lib/sidebar/inspector-tab.svelte

@@ -38,11 +38,14 @@ from the Phase 10 stub.
 		if (report === undefined || report === null) return null;
 		return report.planets.find((p) => p.number === sel.id) ?? null;
 	});
+	const localShipClass = $derived(
+		renderedReport?.report?.localShipClass ?? [],
+	);
 </script>
 
 <section class="tool" data-testid="sidebar-tool-inspector">
 	{#if selectedPlanet !== null}
-		<Planet planet={selectedPlanet} />
+		<Planet planet={selectedPlanet} {localShipClass} />
 	{:else}
 		<h3>{i18n.t("game.sidebar.tab.inspector")}</h3>
 		<p>{i18n.t("game.sidebar.empty.inspector")}</p>

ui/frontend/src/lib/sidebar/order-tab.svelte

@@ -19,6 +19,7 @@ Tests exercise the tab through `__galaxyDebug.seedOrderDraft`
 <script lang="ts">
 	import { getContext } from "svelte";
 	import { i18n, type TranslationKey } from "$lib/i18n/index.svelte";
+	import { productionDisplayFromCommand } from "../../api/game-state";
 	import {
 		ORDER_DRAFT_CONTEXT_KEY,
 		OrderDraftStore,
@@ -49,6 +50,14 @@ Tests exercise the tab through `__galaxyDebug.seedOrderDraft`
 					planet: String(cmd.planetNumber),
 					name: cmd.name,
 				});
+			case "setProductionType":
+				return i18n.t("game.sidebar.order.label.planet_production", {
+					planet: String(cmd.planetNumber),
+					target: productionDisplayFromCommand(
+						cmd.productionType,
+						cmd.subject,
+					),
+				});
 		}
 	}
 

ui/frontend/src/routes/games/[id]/+layout.svelte

@@ -117,6 +117,9 @@ fresh.
 		if (report === null) return null;
 		return report.planets.find((p) => p.number === sel.id) ?? null;
 	});
+	const localShipClass = $derived(
+		renderedReport.report?.localShipClass ?? [],
+	);
 
 	// Reveal the inspector whenever a new planet selection lands.
 	// Reading `selection.selected` once outside the effect keeps the
@@ -224,6 +227,7 @@ fresh.
 	/>
 	<PlanetSheet
 		planet={selectedPlanet}
+		{localShipClass}
 		onMap={effectiveTool === "map"}
 		onClose={() => selection.clear()}
 	/>

ui/frontend/src/sync/order-draft.svelte.ts

@@ -173,11 +173,41 @@ export class OrderDraftStore {
 	 * triggers an auto-sync to keep the server in lock-step.
 	 * Mutations made before `init` resolves are ignored — the layout
 	 * always awaits `init` before exposing the store.
+	 *
+	 * `setProductionType` carries a collapse-by-`planetNumber` rule:
+	 * a new entry supersedes any prior `setProductionType` for the
+	 * same planet, so the draft holds at most one production choice
+	 * per planet at any time. Other variants append unconditionally —
+	 * `planetRename` keeps its append-only behaviour because each
+	 * rename is a distinct user-visible action.
 	 */
 	async add(command: OrderCommand): Promise<void> {
 		if (this.status !== "ready") return;
-		this.commands = [...this.commands, command];
-		this.statuses = { ...this.statuses, [command.id]: validateCommand(command) };
+		const removed: string[] = [];
+		let nextCommands: OrderCommand[];
+		if (command.kind === "setProductionType") {
+			nextCommands = [];
+			for (const existing of this.commands) {
+				if (
+					existing.kind === "setProductionType" &&
+					existing.planetNumber === command.planetNumber
+				) {
+					removed.push(existing.id);
+					continue;
+				}
+				nextCommands.push(existing);
+			}
+			nextCommands.push(command);
+		} else {
+			nextCommands = [...this.commands, command];
+		}
+		this.commands = nextCommands;
+		const nextStatuses = { ...this.statuses };
+		for (const id of removed) {
+			delete nextStatuses[id];
+		}
+		nextStatuses[command.id] = validateCommand(command);
+		this.statuses = nextStatuses;
 		await this.persist();
 		this.scheduleSync();
 	}
@@ -400,6 +430,20 @@ function validateCommand(cmd: OrderCommand): CommandStatus {
 	switch (cmd.kind) {
 		case "planetRename":
 			return validateEntityName(cmd.name).ok ? "valid" : "invalid";
+		case "setProductionType":
+			// Mirrors the engine's `subject=Production` validator
+			// (`game/internal/router/validator.go`): SCIENCE and SHIP
+			// require a non-empty entity-name-valid subject; the other
+			// six production types accept any subject (typically empty)
+			// because the engine only consults the subject for those
+			// two cases.
+			if (
+				cmd.productionType === "SCIENCE" ||
+				cmd.productionType === "SHIP"
+			) {
+				return validateEntityName(cmd.subject).ok ? "valid" : "invalid";
+			}
+			return "valid";
 		case "placeholder":
 			// Phase 12 placeholder entries are content-free and never
 			// transition out of `draft` — they are not submittable.

ui/frontend/src/sync/order-load.ts

@@ -12,11 +12,13 @@ import { uuidToHiLo } from "../api/game-state";
 import { UUID } from "../proto/galaxy/fbs/common";
 import {
 	CommandPayload,
+	CommandPlanetProduce,
 	CommandPlanetRename,
+	PlanetProduction,
 	UserGamesOrderGet,
 	UserGamesOrderGetResponse,
 } from "../proto/galaxy/fbs/order";
-import type { OrderCommand } from "./order-types";
+import type { OrderCommand, ProductionType } from "./order-types";
 
 const MESSAGE_TYPE = "user.games.order.get";
 
@@ -135,6 +137,24 @@ function decodeCommand(item: CommandItemView): OrderCommand | null {
 				name: inner.name() ?? "",
 			};
 		}
+		case CommandPayload.CommandPlanetProduce: {
+			const inner = new CommandPlanetProduce();
+			item.payload(inner);
+			const productionType = productionTypeFromFBS(inner.production());
+			if (productionType === null) {
+				console.warn(
+					`fetchOrder: skipping CommandPlanetProduce with unknown production enum (${inner.production()})`,
+				);
+				return null;
+			}
+			return {
+				kind: "setProductionType",
+				id,
+				planetNumber: Number(inner.number()),
+				productionType,
+				subject: inner.subject() ?? "",
+			};
+		}
 		default:
 			console.warn(
 				`fetchOrder: skipping unknown command kind (payloadType=${payloadType})`,
@@ -143,6 +163,39 @@ function decodeCommand(item: CommandItemView): OrderCommand | null {
 	}
 }
 
+/**
+ * productionTypeFromFBS reverses `productionTypeToFBS` from
+ * `submit.ts`. `PlanetProduction.UNKNOWN` and any out-of-band value
+ * yield `null` so the caller drops the entry instead of fabricating a
+ * synthetic kind.
+ */
+export function productionTypeFromFBS(
+	value: PlanetProduction,
+): ProductionType | null {
+	switch (value) {
+		case PlanetProduction.MAT:
+			return "MAT";
+		case PlanetProduction.CAP:
+			return "CAP";
+		case PlanetProduction.DRIVE:
+			return "DRIVE";
+		case PlanetProduction.WEAPONS:
+			return "WEAPONS";
+		case PlanetProduction.SHIELDS:
+			return "SHIELDS";
+		case PlanetProduction.CARGO:
+			return "CARGO";
+		case PlanetProduction.SCIENCE:
+			return "SCIENCE";
+		case PlanetProduction.SHIP:
+			return "SHIP";
+		case PlanetProduction.UNKNOWN:
+			return null;
+		default:
+			return null;
+	}
+}
+
 function decodeError(
 	payload: Uint8Array,
 	resultCode: string,

ui/frontend/src/sync/order-types.ts

@@ -40,13 +40,85 @@ export interface PlanetRenameCommand {
 	readonly name: string;
 }
 
+/**
+ * ProductionType mirrors the engine `PlanetProduction` enum
+ * (`pkg/schema/fbs/order.fbs`) and the binding tag on
+ * `pkg/model/order/order.go.CommandPlanetProduce.Production`. The
+ * values are wire-stable: the submit encoder maps them to the FBS
+ * enum, the read-back decoder maps them back, and the optimistic
+ * overlay derives the engine's display string from the same set.
+ *
+ * `MAT` is materials production, `CAP` is industry (the engine names
+ * carry historical meaning — "Material" and "Capital" in the display
+ * mapping). `DRIVE` / `WEAPONS` / `SHIELDS` / `CARGO` are the four
+ * implicit per-tech research tracks (no subject required). `SCIENCE`
+ * is research of a custom science package authored via
+ * `CommandScienceCreate`; `SHIP` is build of a ship class authored
+ * via `CommandShipClassCreate`. Both `SCIENCE` and `SHIP` require a
+ * non-empty `subject` that passes `validateEntityName`; the engine
+ * validator (`game/internal/router/validator.go`) enforces the same.
+ */
+export type ProductionType =
+	| "MAT"
+	| "CAP"
+	| "DRIVE"
+	| "WEAPONS"
+	| "SHIELDS"
+	| "CARGO"
+	| "SCIENCE"
+	| "SHIP";
+
+/**
+ * SetProductionTypeCommand switches a planet's production target.
+ * Phase 15 is the first variant to carry a collapse-by-target rule:
+ * the order draft store keeps at most one `setProductionType` per
+ * `planetNumber`, replacing any earlier entry on `add`. `subject` is
+ * the science or ship-class name when `productionType` is `SCIENCE`
+ * or `SHIP`; for the other six values it is the empty string.
+ */
+export interface SetProductionTypeCommand {
+	readonly kind: "setProductionType";
+	readonly id: string;
+	readonly planetNumber: number;
+	readonly productionType: ProductionType;
+	readonly subject: string;
+}
+
 /**
  * OrderCommand is the discriminated union of every command shape the
  * local order draft can hold. The `kind` field is the discriminator;
  * narrowing on it enables exhaustive `switch` statements at every
  * call site.
  */
-export type OrderCommand = PlaceholderCommand | PlanetRenameCommand;
+export type OrderCommand =
+	| PlaceholderCommand
+	| PlanetRenameCommand
+	| SetProductionTypeCommand;
+
+/**
+ * PRODUCTION_TYPE_VALUES is the canonical tuple of `ProductionType`
+ * literals. Used by validators and by the FBS converters in
+ * `submit.ts` and `order-load.ts` to assert that an incoming string
+ * is one of the wire-stable values.
+ */
+export const PRODUCTION_TYPE_VALUES = [
+	"MAT",
+	"CAP",
+	"DRIVE",
+	"WEAPONS",
+	"SHIELDS",
+	"CARGO",
+	"SCIENCE",
+	"SHIP",
+] as const satisfies readonly ProductionType[];
+
+/**
+ * isProductionType narrows an arbitrary string to the
+ * `ProductionType` union.
+ */
+export function isProductionType(value: string): value is ProductionType {
+	return (PRODUCTION_TYPE_VALUES as readonly string[]).includes(value);
+}
 
 /**
  * CommandStatus is the lifecycle of a single command from the moment

ui/frontend/src/sync/submit.ts

@@ -27,11 +27,13 @@ import { UUID } from "../proto/galaxy/fbs/common";
 import {
 	CommandItem,
 	CommandPayload,
+	CommandPlanetProduce,
 	CommandPlanetRename,
+	PlanetProduction,
 	UserGamesOrder,
 	UserGamesOrderResponse,
 } from "../proto/galaxy/fbs/order";
-import type { OrderCommand } from "./order-types";
+import type { OrderCommand, ProductionType } from "./order-types";
 
 const MESSAGE_TYPE = "user.games.order";
 
@@ -148,6 +150,19 @@ function encodeCommandPayload(
 				payloadOffset: offset,
 			};
 		}
+		case "setProductionType": {
+			const subjectOffset = builder.createString(cmd.subject);
+			const offset = CommandPlanetProduce.createCommandPlanetProduce(
+				builder,
+				BigInt(cmd.planetNumber),
+				productionTypeToFBS(cmd.productionType),
+				subjectOffset,
+			);
+			return {
+				payloadType: CommandPayload.CommandPlanetProduce,
+				payloadOffset: offset,
+			};
+		}
 		case "placeholder":
 			throw new SubmitError(
 				"invalid_request",
@@ -157,6 +172,34 @@ function encodeCommandPayload(
 	}
 }
 
+/**
+ * productionTypeToFBS converts the wire-stable `ProductionType` literal
+ * to the FlatBuffers enum value. Mirrors `planetProductionToFBS` in
+ * `pkg/transcoder/order.go`. The two sides are kept in lock-step so the
+ * gateway can decode whatever the frontend produces without a
+ * translation step.
+ */
+export function productionTypeToFBS(value: ProductionType): PlanetProduction {
+	switch (value) {
+		case "MAT":
+			return PlanetProduction.MAT;
+		case "CAP":
+			return PlanetProduction.CAP;
+		case "DRIVE":
+			return PlanetProduction.DRIVE;
+		case "WEAPONS":
+			return PlanetProduction.WEAPONS;
+		case "SHIELDS":
+			return PlanetProduction.SHIELDS;
+		case "CARGO":
+			return PlanetProduction.CARGO;
+		case "SCIENCE":
+			return PlanetProduction.SCIENCE;
+		case "SHIP":
+			return PlanetProduction.SHIP;
+	}
+}
+
 function decodeOrderResponse(
 	payload: Uint8Array,
 	commands: OrderCommand[],