Smithing table

MODS.md

@@ -349,8 +349,23 @@ clients as part of the container it's in, so client screens can show it.
 | `type`    | Fields                                                                             | Notes                                                                        |
 | --------- | ---------------------------------------------------------------------------------- | ---------------------------------------------------------------------------- |
 | `shaped`  | `pattern` rows (space is empty), `key` letter to item id, `result` `{ id, count }` | Fits anywhere in the 3×3 grid, like the recipes in `server/game/crafting.ts` |
-| `furnace` | `input` item id, `output` `{ id, count }`, `cook_time` in ticks                    | Same as `FURNACE_RECIPES` in `server/game/blocks.ts`                         |
-| `fuel`    | `item` id, `burn_time` in ticks                                                    | Same as `FUEL_VALUES` in `server/game/blocks.ts`                             |
+| `furnace` | `input` item id, `output` `{ id, count }`, `cook_time` in ticks                    | Used by the furnace                                                          |
+| `fuel`    | `item` id, `burn_time` in ticks                                                    | Used by the furnace                                                          |
+| `smithing` | `tool` item id, `material` `{ id, count }`, optional `addition` item id, `result` item id | Used by the smithing table: upgrades the tool, keeping its data. Uses up the tool, `count` of the material and the addition |
+
+A smithing recipe, `recipes/smithing_stone_pickaxe.json`:
+
+```json
+{
+	"format_version": 1,
+	"recipe": {
+		"type": "smithing",
+		"tool": "bworld:wood_pickaxe",
+		"material": { "id": "bworld:stone", "count": 5 },
+		"result": "bworld:stone_pickaxe"
+	}
+}
+```
 
 A shaped recipe, for the crafting grid in the player's inventory screen:
 
@@ -366,7 +381,8 @@ A shaped recipe, for the crafting grid in the player's inventory screen:
 }
 ```
 
-Two furnace recipes with the same `input`, or two shaped recipes with the same pattern and key, are a load error. Server
+Two furnace recipes with the same `input`, two smithing recipes with the same tool, material and addition, or two
+shaped recipes with the same pattern and key, are a load error. Server
 scripts can also register recipe types of their own through `ctx.recipes`.
 
 ## Server scripts
@@ -655,7 +671,9 @@ ctx.components.register_block("copper_tools:smelter", {
   can be fractional. `rows` sets its height, by default it fits the slots and bars.
 - `filter` is a function `(item) => boolean` or one of the built-in filters `"smeltable"` (has a furnace recipe) and
   `"fuel"`. It and `output_only` run **on the server**, so players can't put the wrong items in by editing their client.
-  `output_only` slots can only be taken from, all at once, like the furnace result.
+  `output_only` slots can only be taken from, all at once, like the furnace result. Their `on_take(item)` runs when a
+  player takes from one, before they get it: return `false` to stop them, or use up the inputs there so they're gone in
+  the same step (the smithing table does this).
 - `bars` are progress bars filled with `value / max`, both names of properties set with `screen.set_property(id, n)`.
   `direction` is `"up"` (like the furnace's fire) or `"right"` (like its arrow). Properties are synced when they change,
   so a component can update them every tick.

common/inventory.ts

@@ -258,6 +258,12 @@ function right_click(container: Container, index: number, cursor: Cursor) {
 	slot.amount = half;
 }
 
+// whether take_output would take it
+export function can_take_output(item: ItemStack, cursor: Cursor): boolean {
+	const holding = cursor.item;
+	return !holding || (holding.type_id === item.type_id && holding.max_amount - holding.amount >= item.amount);
+}
+
 // output slots (furnace result, crafting result) can only be taken from, all at once
 // returns whether it was taken
 export function take_output(item: ItemStack, cursor: Cursor): boolean {

common/mod_api/server.ts

@@ -191,6 +191,8 @@ export interface RecipeApi {
 	fuel_value(item: Id): number; // burn time in ticks, 0 if it isn't fuel
 	is_fuel(item: Id): boolean;
 	is_smeltable(item: Id): boolean;
+	// the smithing recipe for these items, whatever the material's count. addition is the optional third item
+	smithing(tool: Id, material: Id, addition?: Id): { result: Id; material_count: number } | undefined;
 }
 
 // guis
@@ -233,6 +235,8 @@ export interface ContainerScreenOptions {
 		filter?: SlotFilter;
 		// can only be taken from, all at once, like the furnace result
 		output_only?: boolean;
+		// runs when a player takes from an output_only slot, before they get it. false stops them taking it
+		on_take?: (item: ItemStack) => boolean;
 	}[];
 	// height of the screen's area in slots, fits the layout and bars when not set
 	rows?: number;

common/mod_data.ts

@@ -78,7 +78,15 @@ export type RecipeJson =
 		result: { id: string; count: number };
 	}
 	| { type: "furnace"; input: string; output: { id: string; count: number }; cook_time: number }
-	| { type: "fuel"; item: string; burn_time: number };
+	| { type: "fuel"; item: string; burn_time: number }
+	// upgrades a tool at a smithing table, with some of a material and maybe one more item
+	| {
+		type: "smithing";
+		tool: string;
+		material: { id: string; count: number };
+		addition?: string;
+		result: string;
+	};
 
 // the crafting grid's format, see server/game/crafting.ts
 export interface GridRecipe {
@@ -447,8 +455,16 @@ export function validate_recipe(json: unknown): Problems {
 				problems.push("burn_time must be a positive number of ticks");
 			}
 			break;
+		case "smithing":
+			problems.push(
+				...validate_id(json.tool, "tool"),
+				...validate_stack(json.material, "material"),
+				...validate_id(json.result, "result"),
+			);
+			if (json.addition !== undefined) problems.push(...validate_id(json.addition, "addition"));
+			break;
 		default:
-			problems.push('type must be "shaped", "furnace" or "fuel"');
+			problems.push('type must be "shaped", "furnace", "fuel" or "smithing"');
 	}
 	return problems;
 }

common/mod_loader.ts

@@ -50,6 +50,7 @@ export class RecipeBook {
 	shaped: GridRecipe[] = [];
 	furnace = new Map<string, { output: { id: string; count: number }; cook_time: number }>();
 	fuel = new Map<string, number>();
+	smithing: Extract<RecipeJson, { type: "smithing" }>[] = [];
 	ores: OreJson[] = [];
 }
 
@@ -98,6 +99,17 @@ export function register_mod_data(mods: { id: string; data: ModData }[]): Recipe
 				case "fuel":
 					recipes.fuel.set(recipe.item, recipe.burn_time);
 					break;
+				case "smithing":
+					if (
+						recipes.smithing.some((other) =>
+							other.tool === recipe.tool && other.material.id === recipe.material.id &&
+							other.addition === recipe.addition
+						)
+					) {
+						fail(`two smithing recipes for ${recipe.tool} with ${recipe.material.id}`);
+					}
+					recipes.smithing.push(recipe);
+					break;
 			}
 		}
 		recipes.ores.push(...data.ores);

mods/bworld/blocks/smithing_table.json

@@ -0,0 +1,21 @@
+{
+	"format_version": 1,
+	"block": {
+		"id": "bworld:smithing_table",
+		"textures": {
+			"top": "bworld:smithing_table_top",
+			"bottom": "bworld:smithing_table_bottom",
+			"front": "bworld:smithing_table_front",
+			"side": "bworld:smithing_table_side"
+		},
+		"mining": {
+			"toughness": 5,
+			"tool": "axe"
+		},
+		"drops": "bworld:smithing_table",
+		"interactive": true,
+		"components": {
+			"bworld:smithing_table": {}
+		}
+	}
+}

mods/bworld/items/stone_pickaxe.json

@@ -0,0 +1,8 @@
+{
+	"format_version": 1,
+	"item": {
+		"id": "bworld:stone_pickaxe",
+		"texture": "bworld:stone_pickaxe",
+		"tool": "pickaxe"
+	}
+}

mods/bworld/recipes/smithing_stone_pickaxe.json

@@ -0,0 +1,12 @@
+{
+	"format_version": 1,
+	"recipe": {
+		"type": "smithing",
+		"tool": "bworld:wood_pickaxe",
+		"material": {
+			"id": "bworld:stone",
+			"count": 5
+		},
+		"result": "bworld:stone_pickaxe"
+	}
+}

mods/bworld/scripts/server.ts

@@ -5,6 +5,7 @@ export function setup(ctx: ServerContext) {
 	register_hoeable(ctx);
 	register_storage(ctx);
 	register_furnace(ctx);
+	register_smithing_table(ctx);
 	register_crop(ctx);
 	register_watering_can(ctx);
 }
@@ -196,6 +197,81 @@ function register_furnace(ctx: ServerContext) {
 	});
 }
 
+// smithing table: a tool, some of a material and maybe a third item make a better tool, see the smithing recipes.
+// every player gets their own slots, and what's left in them goes back to the player when they close it
+
+const TOOL = 0;
+const MATERIAL = 1;
+const ADDITION = 2;
+const RESULT = 3;
+
+function register_smithing_table(ctx: ServerContext) {
+	ctx.components.register_block("bworld:smithing_table", {
+		on_interact(_block, _params, player) {
+			const container = ctx.containers.create(4);
+
+			// the recipe the inputs make, with enough material
+			const match = () => {
+				const tool = container.get(TOOL);
+				const material = container.get(MATERIAL);
+				const addition = container.get(ADDITION);
+				if (!tool || !material) return undefined;
+				const recipe = ctx.recipes.smithing(tool.id, material.id, addition?.id);
+				if (!recipe || material.count < recipe.material_count) return undefined;
+				return { ...recipe, tool, material, addition };
+			};
+
+			// the result slot shows what taking it would give, the upgraded tool keeps the old one's data
+			const show_result = () => {
+				const recipe = match();
+				const shown = container.get(RESULT);
+				if (!recipe) {
+					if (shown) container.set(RESULT, undefined);
+				} else if (shown?.id !== recipe.result) {
+					container.set(RESULT, { id: recipe.result, count: 1, data: recipe.tool.data });
+				}
+			};
+			const stop = container.on_change((slot) => {
+				if (slot !== RESULT) show_result();
+			});
+
+			const screen = ctx.ui.open_container(player, {
+				container,
+				layout: [
+					{ slot: TOOL, x: 1.5, y: 0.5 },
+					{ slot: MATERIAL, x: 2.5, y: 0.5 },
+					{ slot: ADDITION, x: 3.5, y: 0.5 },
+					{
+						slot: RESULT,
+						x: 5.5,
+						y: 0.5,
+						output_only: true,
+						// the inputs are used up in the same step, so they can't be taken out after
+						on_take(item) {
+							const recipe = match();
+							if (!recipe || recipe.result !== item.id) return false;
+							recipe.tool.count -= 1;
+							recipe.material.count -= recipe.material_count;
+							if (recipe.addition) recipe.addition.count -= 1;
+							return true;
+						},
+					},
+				],
+				rows: 2,
+			});
+			screen.on_close(() => {
+				stop();
+				for (const slot of [TOOL, MATERIAL, ADDITION]) {
+					const item = container.get(slot);
+					if (item) player.give_item(item.id, item.count, item.data);
+				}
+				ctx.containers.delete(container.id);
+			});
+			return true;
+		},
+	});
+}
+
 // grows one stage each time it's right clicked with the fertilizer, like bone meal on wheat
 function register_crop(ctx: ServerContext) {
 	ctx.components.register_block<{ fertilizer: string; max_age: number }>("bworld:crop", {

server/game/game_server.ts

@@ -12,7 +12,7 @@ import {
 	TICKS_PER_SECOND,
 } from "$/common/constants.ts";
 import { BlockRegistry, EverythingRegistry, ItemRegistry } from "$/common/everything_registry.ts";
-import { click_slot, Container, ItemData, ItemStack, take_output } from "$/common/inventory.ts";
+import { can_take_output, click_slot, Container, ItemData, ItemStack, take_output } from "$/common/inventory.ts";
 import {
 	AIR_ID,
 	BlockChange,
@@ -744,7 +744,8 @@ export class GameServer {
 			}
 		} else if (key === "screen" && player.screen?.layout.slots.find((s) => s.index === index)?.output) {
 			const item = container.get_item(index);
-			if (item && take_output(item, player.cursor)) {
+			const allowed = (item: ItemStack) => player.screen?.on_take.get(index)?.(item) ?? true;
+			if (item && can_take_output(item, player.cursor) && allowed(item) && take_output(item, player.cursor)) {
 				container.set_item(index, undefined);
 			}
 		} else if (

server/game/mod_runtime.ts

@@ -391,6 +391,12 @@ export class ModRuntime {
 				fuel_value: (item) => game().recipes.fuel.get(item) ?? 0,
 				is_fuel: (item) => game().recipes.fuel.has(item),
 				is_smeltable: (item) => game().recipes.furnace.has(item),
+				smithing: (tool, material, addition) => {
+					const recipe = game().recipes.smithing.find((r) =>
+						r.tool === tool && r.material.id === material && r.addition === addition
+					);
+					return recipe && { result: recipe.result, material_count: recipe.material.count };
+				},
 			},
 			containers: {
 				create: (size) => {
@@ -442,7 +448,11 @@ export class ModRuntime {
 		}
 
 		const filters = new Map<number, (item: EngineItemStack) => boolean>();
-		for (const { slot, filter } of options.layout) {
+		const on_take = new Map<number, (item: EngineItemStack) => boolean>();
+		for (const { slot, filter, on_take: take } of options.layout) {
+			if (take) {
+				on_take.set(slot, (item) => run_guarded(mod, "an on_take", () => take(item_api(item))) === true);
+			}
 			if (!Number.isInteger(slot) || slot < 0 || slot >= container.size) {
 				throw new Error(`slot ${slot} isn't in the container, it has ${container.size}`);
 			}
@@ -474,7 +484,14 @@ export class ModRuntime {
 		};
 
 		let open = true;
-		const screen: OpenScreen = { container, layout, properties: {}, filters, on_close: [() => open = false] };
+		const screen: OpenScreen = {
+			container,
+			layout,
+			properties: {},
+			filters,
+			on_take,
+			on_close: [() => open = false],
+		};
 		game.open_screen(server_player, screen);
 
 		return {

server/game/player.ts

@@ -12,6 +12,8 @@ export interface OpenScreen {
 	properties: Record<string, number>;
 	// what can go into each slot, checked when the player clicks
 	filters: Map<number, (item: ItemStack) => boolean>;
+	// asked before a player takes from an output slot
+	on_take: Map<number, (item: ItemStack) => boolean>;
 	on_close: (() => void)[];
 }
 

tests/base_game_test.ts

@@ -195,3 +195,70 @@ Deno.test("chests and furnaces from a world saved before they were mod code keep
 	assert(saved.tiles.every((tile: Msg) => tile.data === undefined && tile.containers === undefined));
 	assertEquals(Object.keys(saved.containers).length, 2);
 });
+
+Deno.test("a smithing table upgrades a wooden pickaxe with 5 stone, using up exactly that", async () => {
+	const t = await setup([["bworld:wood_pickaxe", 1], ["bworld:stone", 7]]);
+	t.game.set_block(1, 100, 0, "bworld:smithing_table");
+	let messages = t.take(1);
+	const pickaxe = slot_of(messages, "bworld:wood_pickaxe");
+	const stone = slot_of(messages, "bworld:stone");
+
+	t.send(1, { type: "use_block", x: 1, y: 100, z: 0, face: "top" });
+	const opened = t.take(1).find((m) => m.type === "open_screen");
+	assertEquals(opened.layout.slots.map((s: Msg) => [s.index, s.output ?? false]), [
+		[0, false],
+		[1, false],
+		[2, false],
+		[3, true],
+	]);
+
+	// with only the tool there's nothing to take
+	move_to_screen(t, pickaxe, 0);
+	t.game.tick();
+	t.send(1, { type: "click", container: "screen", index: 3, button: 0 });
+	assertEquals(t.take(1).filter((m) => m.type === "cursor").at(-1)?.item ?? null, null);
+
+	// the result shows up once there's enough stone, and taking it uses up the pickaxe and 5 stone
+	move_to_screen(t, stone, 1);
+	t.game.tick();
+	assertEquals(last_container(t.take(1), "screen")[3], { id: "bworld:stone_pickaxe", count: 1 });
+	t.send(1, { type: "click", container: "screen", index: 3, button: 0 });
+	messages = t.take(1);
+	assertEquals(messages.filter((m) => m.type === "cursor").at(-1).item, { id: "bworld:stone_pickaxe", count: 1 });
+	assertEquals(last_container(messages, "screen"), [null, { id: "bworld:stone", count: 2 }, null, null]);
+
+	// closing gives back the leftover stone, and the cursor's pickaxe goes into the inventory
+	t.send(1, { type: "close_screen" });
+	const inventory = last_container(t.take(1), "inventory").filter((i: Msg) => i);
+	assertEquals(
+		inventory.sort((a: Msg, b: Msg) => a.id.localeCompare(b.id)),
+		[{ id: "bworld:stone", count: 2 }, { id: "bworld:stone_pickaxe", count: 1 }],
+	);
+	assertEquals(t.game.containers.size, 0);
+});
+
+Deno.test("a smithing result can't be taken once its inputs are gone, even before it updates", async () => {
+	const t = await setup([["bworld:wood_pickaxe", 1], ["bworld:stone", 5]]);
+	t.game.set_block(1, 100, 0, "bworld:smithing_table");
+	const messages = t.take(1);
+	t.send(1, { type: "use_block", x: 1, y: 100, z: 0, face: "top" });
+	move_to_screen(t, slot_of(messages, "bworld:wood_pickaxe"), 0);
+	move_to_screen(t, slot_of(messages, "bworld:stone"), 1);
+	t.game.tick();
+
+	// take the pickaxe back out and try the result in the same tick
+	t.send(1, { type: "click", container: "screen", index: 0, button: 0 });
+	t.send(1, { type: "click", container: "inventory", index: 20, button: 0 });
+	t.send(1, { type: "click", container: "screen", index: 3, button: 0 });
+	const cursor = t.take(1).filter((m) => m.type === "cursor").at(-1).item;
+	assertEquals(cursor, null);
+
+	// and an extra item in the third slot doesn't match a recipe without one
+	t.send(1, { type: "click", container: "inventory", index: 20, button: 0 });
+	t.send(1, { type: "click", container: "screen", index: 0, button: 0 });
+	t.send(1, { type: "chat", text: "/give bworld:coal 1" });
+	const coal = slot_of(t.take(1), "bworld:coal");
+	move_to_screen(t, coal, 2);
+	t.game.tick();
+	assertEquals(last_container(t.take(1), "screen")[3], null);
+});

tests/mod_loading_test.ts

@@ -23,9 +23,9 @@ const inventory_of = (messages: Msg[]) =>
 
 Deno.test("the base game loads from mods/bworld", async () => {
 	const { game } = await test_game("mods");
-	assertEquals(EverythingRegistry.entries("blocks").length, 20);
-	// 14 items plus the item forms of the 17 blocks that have one
-	assertEquals(EverythingRegistry.entries("items").length, 31);
+	assertEquals(EverythingRegistry.entries("blocks").length, 21);
+	// 15 items plus the item forms of the 18 blocks that have one
+	assertEquals(EverythingRegistry.entries("items").length, 33);
 	assertEquals(game.recipes.shaped.length, 5);
 	assertEquals(game.recipes.furnace.size, 6);
 	assertEquals(game.recipes.fuel.size, 2);

tools/check_mods.ts

@@ -280,6 +280,12 @@ function check_references(mods: LoadedMod[]) {
 				case "fuel":
 					uses(file, json.item, "item");
 					break;
+				case "smithing":
+					uses(file, json.tool, "item");
+					uses(file, json.material.id, "item");
+					if (json.addition) uses(file, json.addition, "item");
+					uses(file, json.result, "item");
+					break;
 			}
 		}
 		for (const { file, json } of mod.ores) {