import fs from "node:fs";
import path from "node:path";
import vue from "@vitejs/plugin-vue";
import { defineConfig, type Plugin } from "vite";

const repoWasmDir = path.resolve(__dirname, "../public/wasm");

// 复用主项目已经构建好的 WASM 文件，开发时映射 /wasm，打包时复制到 dist/wasm。
function repoWasmAssets(): Plugin {
  return {
    name: "repo-wasm-assets",
    configureServer(server) {
      server.middlewares.use("/wasm", (req, res, next) => {
        const requestPath = decodeURIComponent((req.url || "").split("?")[0].replace(/^\/+/, ""));
        const filePath = path.resolve(repoWasmDir, requestPath);
        if (!filePath.startsWith(repoWasmDir) || !fs.existsSync(filePath)) {
          next();
          return;
        }

        if (filePath.endsWith(".wasm")) {
          res.setHeader("Content-Type", "application/wasm");
        } else if (filePath.endsWith(".js")) {
          res.setHeader("Content-Type", "application/javascript; charset=utf-8");
        }

        fs.createReadStream(filePath).pipe(res);
      });
    },
    closeBundle() {
      const outDir = path.resolve(__dirname, "dist/wasm");
      fs.mkdirSync(outDir, { recursive: true });
      for (const assetName of ["smart_math.js", "smart_math.wasm"]) {
        const source = path.join(repoWasmDir, assetName);
        if (fs.existsSync(source)) {
          fs.copyFileSync(source, path.join(outDir, assetName));
        }
      }
    }
  };
}

export default defineConfig({
  plugins: [vue(), repoWasmAssets()],
  server: {
    port: 5174
  }
});