import {promises as fsp} from "fs";

const prefix = "json:";

export default function ejsAssetPlugin() {
  return {
    name: "json-plugin",
    async resolveId(id, importer) {
      if (!id.startsWith(prefix)) return;
      const realId = id.slice(prefix.length);
      const resolveResult = await this.resolve(realId, importer);

      if (!resolveResult) {
        throw Error(`Cannot find ${realId}`);
      }
      // Add an additional .js to the end so it ends up with .js at the end in the _virtual folder.
      return prefix + resolveResult.id;
    },
    async load(id) {
      if (!id.startsWith(prefix)) return;
      const realId = id.slice(prefix.length);
      const source = await fsp.readFile(realId, "utf8");

	  let code = "";
		for(const [key, value] of Object.entries(JSON.parse(source))) {
			code += `
				export const ${key} = ${JSON.stringify(value)};
			`
		}
		return code;
    },
  };
}