import type { RootContent } from "hast";
import { fromMarkdown } from "mdast-util-from-markdown";
import { fromHtml } from "hast-util-from-html";
import { toHtml } from "hast-util-to-html";
import { spawnSync } from "node:child_process";
import {
mkdirSync,
mkdtempSync,
readFileSync,
existsSync,
readdirSync,
copyFileSync,
writeFileSync,
} from "node:fs";
import { tmpdir } from "node:os";
import { join, parse, resolve, basename } from "node:path";
import { visit } from "unist-util-visit";
import type { RemarkPlugin } from "@astrojs/markdown-remark";
interface Options {
base: string;
outDir: string;
publicDir: string;
}
const remarkAgda: RemarkPlugin = ({ base, publicDir }: Options) => {
const destDir = join(publicDir, "generated", "agda");
mkdirSync(destDir, { recursive: true });
return (tree, { history }) => {
const path: string = history[history.length - 1]!;
if (!(path.endsWith(".lagda.md") || path.endsWith(".agda"))) return;
// console.log("AGDA:processing path", path);
const tempDir = mkdtempSync(join(tmpdir(), "agdaRender."));
const agdaOutDir = join(tempDir, "output");
mkdirSync(agdaOutDir, { recursive: true });
const childOutput = spawnSync(
"agda",
[
"--html",
`--html-dir=${agdaOutDir}`,
"--highlight-occurrences",
"--html-highlight=code",
path,
],
{},
);
// Locate output file
const directory = readdirSync(agdaOutDir);
const outputFilename = directory.find((name) => name.endsWith(".md"));
if (childOutput.status !== 0 || outputFilename === undefined) {
throw new Error(
`Agda output:
Stdout:
${childOutput.stdout}
Stderr:
${childOutput.stderr}
`,
{
cause: childOutput.error,
},
);
}
const outputFile = join(agdaOutDir, outputFilename);
// // TODO: Handle child output
// console.error("--AGDA OUTPUT--");
// console.error(childOutput);
// console.error(childOutput.stdout?.toString());
// console.error(childOutput.stderr?.toString());
// console.error("--AGDA OUTPUT--");
const referencedFiles = new Set();
for (const file of readdirSync(agdaOutDir)) {
referencedFiles.add(file);
const fullPath = join(agdaOutDir, file);
const fullDestPath = join(destDir, file);
if (file.endsWith(".html")) {
const src = readFileSync(fullPath);
writeFileSync(
fullDestPath,
`
${src}
`,
);
} else {
copyFileSync(fullPath, fullDestPath);
}
}
const htmlname = basename(resolve(outputFile)).replace(/(\.lagda)?\.md/, ".html");
const doc = readFileSync(outputFile);
// This is the post-processed markdown with HTML code blocks replacing the Agda code blocks
const tree2 = fromMarkdown(doc);
const collectedCodeBlocks: RootContent[] = [];
visit(tree2, "html", (node) => {
const html = fromHtml(node.value, { fragment: true });
const firstChild: RootContent = html.children[0]!;
visit(html, "element", (node) => {
if (node.tagName !== "a") return;
if (node.properties.href) {
// Trim off end
const [href, hash, ...rest] = node.properties.href.split("#");
if (rest.length > 0) throw new Error("come look at this");
if (href === htmlname) {
node.properties.href = `#${hash}`;
}
if (referencedFiles.has(href)) {
node.properties.href = `${base}generated/agda/${href}${hash ? `#${hash}` : ""}`;
node.properties.target = "_blank";
}
}
});
if (!firstChild?.properties?.className?.includes("Agda")) return;
const stringContents = toHtml(firstChild);
collectedCodeBlocks.push({
contents: stringContents,
});
});
let idx = 0;
try {
visit(tree, "code", (node) => {
if (!(node.lang === null || node.lang === "agda")) return;
if (idx > collectedCodeBlocks.length) {
throw new Error("failed");
}
node.type = "html";
node.value = collectedCodeBlocks[idx].contents;
idx += 1;
});
} catch (e) {
// TODO: Figure out a way to handle this correctly
// Possibly by diffing?
console.log("Mismatch in number of args. Perhaps there was an empty block?");
}
};
};
export default remarkAgda;