1 files changed, 125 insertions, 0 deletions
diff --git a/apps/web/src/lib/graphics/index.ts b/apps/web/src/lib/graphics/index.ts
new file mode 100644
index 00000000..5286e932
--- /dev/null
+++ b/apps/web/src/lib/graphics/index.ts
@@ -0,0 +1,125 @@
+import { buildDefaultParamValues } from "@/lib/registry";
+import type { ParamValues } from "@/lib/params";
+import { graphicsRegistry } from "./registry";
+import {
+	registerDefaultGraphics,
+	ellipseGraphicDefinition,
+	polygonGraphicDefinition,
+	rectangleGraphicDefinition,
+	starGraphicDefinition,
+} from "./definitions";
+import {
+	DEFAULT_GRAPHIC_SOURCE_SIZE,
+	type GraphicInstance,
+	type GraphicDefinition,
+} from "./types";
+
+const graphicPreviewUrlCache = new Map<string, string>();
+
+const FALLBACK_CORNER_RADIUS_RATIO = 0.2;
+const FALLBACK_FILL_OPACITY = 0.08;
+const FALLBACK_MIN_FONT_SIZE = 12;
+const FALLBACK_FONT_SIZE_RATIO = 0.15;
+
+function buildFallbackPreviewUrl({
+	name,
+	size,
+}: {
+	name: string;
+	size: number;
+}): string {
+	const svg = `
+		<svg xmlns="http://www.w3.org/2000/svg" width="${size}" height="${size}" viewBox="0 0 ${size} ${size}">
+			<rect width="${size}" height="${size}" rx="${size * FALLBACK_CORNER_RADIUS_RATIO}" fill="white" fill-opacity="${FALLBACK_FILL_OPACITY}" />
+			<text x="50%" y="50%" dominant-baseline="middle" text-anchor="middle" fill="white" font-size="${Math.max(FALLBACK_MIN_FONT_SIZE, size * FALLBACK_FONT_SIZE_RATIO)}" font-family="sans-serif">${name}</text>
+		</svg>
+	`;
+	return `data:image/svg+xml;charset=utf-8,${encodeURIComponent(svg)}`;
+}
+
+export function getGraphicDefinition({
+	definitionId,
+}: {
+	definitionId: string;
+}): GraphicDefinition {
+	registerDefaultGraphics();
+	return graphicsRegistry.get(definitionId);
+}
+
+export function buildDefaultGraphicInstance({
+	definitionId,
+}: {
+	definitionId: string;
+}): GraphicInstance {
+	const definition = getGraphicDefinition({ definitionId });
+	return {
+		definitionId,
+		params: buildDefaultParamValues(definition.params),
+	};
+}
+
+export function resolveGraphicParams(
+	definition: GraphicDefinition,
+	params?: ParamValues,
+): ParamValues {
+	return {
+		...buildDefaultParamValues(definition.params),
+		...(params ?? {}),
+	};
+}
+
+export function buildGraphicPreviewUrl({
+	definitionId,
+	params,
+	size = DEFAULT_GRAPHIC_SOURCE_SIZE,
+}: {
+	definitionId: string;
+	params?: ParamValues;
+	size?: number;
+}): string {
+	const definition = getGraphicDefinition({ definitionId });
+	const resolvedParams = resolveGraphicParams(definition, params);
+	const cacheKey = JSON.stringify({ definitionId, resolvedParams, size });
+	const cachedUrl = graphicPreviewUrlCache.get(cacheKey);
+	if (cachedUrl) {
+		return cachedUrl;
+	}
+
+	if (typeof document === "undefined") {
+		return buildFallbackPreviewUrl({ name: definition.name, size });
+	}
+
+	const canvas = document.createElement("canvas");
+	canvas.width = size;
+	canvas.height = size;
+	const ctx = canvas.getContext("2d");
+	if (!ctx) {
+		return buildFallbackPreviewUrl({ name: definition.name, size });
+	}
+
+	definition.render({
+		ctx,
+		params: resolvedParams,
+		width: size,
+		height: size,
+	});
+
+	const previewUrl = canvas.toDataURL("image/png");
+	graphicPreviewUrlCache.set(cacheKey, previewUrl);
+	return previewUrl;
+}
+
+export {
+	DEFAULT_GRAPHIC_SOURCE_SIZE,
+	ellipseGraphicDefinition,
+	graphicsRegistry,
+	polygonGraphicDefinition,
+	rectangleGraphicDefinition,
+	registerDefaultGraphics,
+	starGraphicDefinition,
+};
+export type {
+	GraphicDefinition,
+	GraphicInstance,
+	GraphicRenderContext,
+} from "./types";