1 files changed, 111 insertions, 0 deletions
diff --git a/packages/integrations/mdx/src/plugins.ts b/packages/integrations/mdx/src/plugins.ts
new file mode 100644
index 000000000..c44c8fffd
--- /dev/null
+++ b/packages/integrations/mdx/src/plugins.ts
@@ -0,0 +1,111 @@
+import {
+	rehypeHeadingIds,
+	rehypePrism,
+	rehypeShiki,
+	remarkCollectImages,
+} from '@astrojs/markdown-remark';
+import { createProcessor, nodeTypes } from '@mdx-js/mdx';
+import { rehypeAnalyzeAstroMetadata } from 'astro/jsx/rehype.js';
+import rehypeRaw from 'rehype-raw';
+import remarkGfm from 'remark-gfm';
+import remarkSmartypants from 'remark-smartypants';
+import { SourceMapGenerator } from 'source-map';
+import type { PluggableList } from 'unified';
+import type { MdxOptions } from './index.js';
+import { rehypeApplyFrontmatterExport } from './rehype-apply-frontmatter-export.js';
+import { rehypeInjectHeadingsExport } from './rehype-collect-headings.js';
+import { rehypeImageToComponent } from './rehype-images-to-component.js';
+import rehypeMetaString from './rehype-meta-string.js';
+import { rehypeOptimizeStatic } from './rehype-optimize-static.js';
+
+// Skip nonessential plugins during performance benchmark runs
+const isPerformanceBenchmark = Boolean(process.env.ASTRO_PERFORMANCE_BENCHMARK);
+
+interface MdxProcessorExtraOptions {
+	sourcemap: boolean;
+	experimentalHeadingIdCompat: boolean;
+}
+
+export function createMdxProcessor(mdxOptions: MdxOptions, extraOptions: MdxProcessorExtraOptions) {
+	return createProcessor({
+		remarkPlugins: getRemarkPlugins(mdxOptions),
+		rehypePlugins: getRehypePlugins(mdxOptions, extraOptions),
+		recmaPlugins: mdxOptions.recmaPlugins,
+		remarkRehypeOptions: mdxOptions.remarkRehype,
+		jsxImportSource: 'astro',
+		// Note: disable `.md` (and other alternative extensions for markdown files like `.markdown`) support
+		format: 'mdx',
+		mdExtensions: [],
+		elementAttributeNameCase: 'html',
+		SourceMapGenerator: extraOptions.sourcemap ? SourceMapGenerator : undefined,
+	});
+}
+
+function getRemarkPlugins(mdxOptions: MdxOptions): PluggableList {
+	let remarkPlugins: PluggableList = [];
+
+	if (!isPerformanceBenchmark) {
+		if (mdxOptions.gfm) {
+			remarkPlugins.push(remarkGfm);
+		}
+		if (mdxOptions.smartypants) {
+			remarkPlugins.push(remarkSmartypants);
+		}
+	}
+
+	remarkPlugins.push(...mdxOptions.remarkPlugins, remarkCollectImages);
+
+	return remarkPlugins;
+}
+
+function getRehypePlugins(
+	mdxOptions: MdxOptions,
+	{ experimentalHeadingIdCompat }: MdxProcessorExtraOptions,
+): PluggableList {
+	let rehypePlugins: PluggableList = [
+		// ensure `data.meta` is preserved in `properties.metastring` for rehype syntax highlighters
+		rehypeMetaString,
+		// rehypeRaw allows custom syntax highlighters to work without added config
+		[rehypeRaw, { passThrough: nodeTypes }],
+	];
+
+	const syntaxHighlight = mdxOptions.syntaxHighlight;
+	if (syntaxHighlight && !isPerformanceBenchmark) {
+		const syntaxHighlightType =
+			typeof syntaxHighlight === 'string' ? syntaxHighlight : syntaxHighlight?.type;
+		const excludeLangs =
+			typeof syntaxHighlight === 'object' ? syntaxHighlight?.excludeLangs : undefined;
+		// Apply syntax highlighters after user plugins to match `markdown/remark` behavior
+		if (syntaxHighlightType === 'shiki') {
+			rehypePlugins.push([rehypeShiki, mdxOptions.shikiConfig, excludeLangs]);
+		} else if (syntaxHighlightType === 'prism') {
+			rehypePlugins.push([rehypePrism, excludeLangs]);
+		}
+	}
+
+	rehypePlugins.push(...mdxOptions.rehypePlugins, rehypeImageToComponent);
+
+	if (!isPerformanceBenchmark) {
+		// getHeadings() is guaranteed by TS, so this must be included.
+		// We run `rehypeHeadingIds` _last_ to respect any custom IDs set by user plugins.
+		rehypePlugins.push(
+			[rehypeHeadingIds, { experimentalHeadingIdCompat }],
+			rehypeInjectHeadingsExport,
+		);
+	}
+
+	rehypePlugins.push(
+		// Render info from `vfile.data.astro.frontmatter` as JS
+		rehypeApplyFrontmatterExport,
+		// Analyze MDX nodes and attach to `vfile.data.__astroMetadata`
+		rehypeAnalyzeAstroMetadata,
+	);
+
+	if (mdxOptions.optimize) {
+		// Convert user `optimize` option to compatible `rehypeOptimizeStatic` option
+		const options = mdxOptions.optimize === true ? undefined : mdxOptions.optimize;
+		rehypePlugins.push([rehypeOptimizeStatic, options]);
+	}
+
+	return rehypePlugins;
+}