import { createReadStream } from "node:fs";
import { cp, stat } from "node:fs/promises";
import path from "node:path";
import { fileURLToPath } from "node:url";
import react from "@vitejs/plugin-react";
import { defineConfig, type Plugin } from "vite";

const appRoot = fileURLToPath(new URL(".", import.meta.url));
const pdfjsRoot = path.join(appRoot, "node_modules/pdfjs-dist");
const pdfjsAssetDirs = ["cmaps", "iccs", "standard_fonts", "wasm"];

function pdfjsAssetsPlugin(): Plugin {
  let outDir = path.join(appRoot, "dist");

  function contentType(filePath: string) {
    if (filePath.endsWith(".wasm")) return "application/wasm";
    if (filePath.endsWith(".mjs")) return "text/javascript";
    if (filePath.endsWith(".bcmap")) return "application/octet-stream";
    if (filePath.endsWith(".icc")) return "application/vnd.iccprofile";
    if (filePath.endsWith(".ttf")) return "font/ttf";
    if (filePath.endsWith(".pfb")) return "application/octet-stream";
    return "application/octet-stream";
  }

  return {
    name: "readabook-pdfjs-assets",
    configResolved(config) {
      outDir = path.resolve(config.root, config.build.outDir);
    },
    configureServer(server) {
      server.middlewares.use("/pdfjs", async (request, response, next) => {
        try {
          const requestPath = new URL(request.url ?? "", "http://localhost").pathname;
          const relativePath = decodeURIComponent(requestPath)
            .replace(/^\/+/, "")
            .replace(/^pdfjs\/+/, "");
          const assetPath = path.resolve(pdfjsRoot, relativePath);
          if (!assetPath.startsWith(pdfjsRoot)) {
            next();
            return;
          }
          const asset = await stat(assetPath);
          if (!asset.isFile()) {
            next();
            return;
          }
          response.setHeader("Content-Type", contentType(assetPath));
          createReadStream(assetPath).pipe(response);
        } catch {
          next();
        }
      });
    },
    async writeBundle() {
      await Promise.all(
        pdfjsAssetDirs.map((directory) =>
          cp(path.join(pdfjsRoot, directory), path.join(outDir, "pdfjs", directory), {
            recursive: true,
            force: true
          })
        )
      );
    }
  };
}

export default defineConfig({
  plugins: [react(), pdfjsAssetsPlugin()],
  server: {
    port: 5173,
    proxy: {
      "/auth": "http://127.0.0.1:3000",
      "/admin": "http://127.0.0.1:3000",
      "/books": "http://127.0.0.1:3000",
      "/series": "http://127.0.0.1:3000",
      "/progress": "http://127.0.0.1:3000",
      "/healthz": "http://127.0.0.1:3000"
    }
  }
});