import { eventHandler, createError } from "h3";
import { joinURL, withoutTrailingSlash, withLeadingSlash, parseURL } from "ufo";
import { getAsset, readAsset, isPublicAssetURL } from "#internal/nitro/virtual/public-assets";
const METHODS = ["HEAD", "GET"];
const EncodingMap = { gzip: ".gz", br: ".br" };
export default eventHandler((event) => {
  if (event.req.method && !METHODS.includes(event.req.method)) {
    return;
  }
  let id = decodeURIComponent(withLeadingSlash(withoutTrailingSlash(parseURL(event.req.url).pathname)));
  let asset;
  const encodingHeader = String(event.req.headers["accept-encoding"] || "");
  const encodings = encodingHeader.split(",").map((e) => EncodingMap[e.trim()]).filter(Boolean).sort().concat([""]);
  if (encodings.length > 1) {
    event.res.setHeader("Vary", "Accept-Encoding");
  }
  for (const encoding of encodings) {
    for (const _id of [id + encoding, joinURL(id, "index.html" + encoding)]) {
      const _asset = getAsset(_id);
      if (_asset) {
        asset = _asset;
        id = _id;
        break;
      }
    }
  }
  if (!asset) {
    if (isPublicAssetURL(id)) {
      throw createError({
        statusMessage: "Cannot find static asset " + id,
        statusCode: 404
      });
    }
    return;
  }
  const ifNotMatch = event.req.headers["if-none-match"] === asset.etag;
  if (ifNotMatch) {
    event.res.statusCode = 304;
    event.res.end();
    return;
  }
  const ifModifiedSinceH = event.req.headers["if-modified-since"];
  if (ifModifiedSinceH && asset.mtime) {
    if (new Date(ifModifiedSinceH) >= new Date(asset.mtime)) {
      event.res.statusCode = 304;
      event.res.end();
      return;
    }
  }
  if (asset.type && !event.res.getHeader("Content-Type")) {
    event.res.setHeader("Content-Type", asset.type);
  }
  if (asset.etag && !event.res.getHeader("ETag")) {
    event.res.setHeader("ETag", asset.etag);
  }
  if (asset.mtime && !event.res.getHeader("Last-Modified")) {
    event.res.setHeader("Last-Modified", asset.mtime);
  }
  if (asset.encoding && !event.res.getHeader("Content-Encoding")) {
    event.res.setHeader("Content-Encoding", asset.encoding);
  }
  if (asset.size && !event.res.getHeader("Content-Length")) {
    event.res.setHeader("Content-Length", asset.size);
  }
  return readAsset(id);
});