import path from "node:path";
import fs from "node:fs";
import type { Loader, PluginBuild, ResolveOptions } from "esbuild";
import { Documentation, parse } from "react-docgen";
import * as tsj from "ts-json-schema-generator";
import { DOCUMENT_SCHEMAS_DIR } from "./paths";

/**
 * Made to export the `renderAsync` function out of the user's email template
 * so that issues like https://github.com/resend/react-email/issues/649 don't
 * happen.
 *
 * This avoids multiple versions of React being involved, i.e., the version
 * in the CLI vs. the version the user has on their document.
 *
 * Also, this plugin generates the schema for document components and saves it to .next
 */
export const htmldocsPlugin = (documentTemplates: string[], isBuild: boolean) => ({
  name: "htmldocs-plugin",
  setup: (b: PluginBuild) => {
    b.onLoad(
      { filter: new RegExp(documentTemplates.join("|")) },
      async ({ path: pathToFile }) => {
        let contents = await fs.promises.readFile(pathToFile, "utf8");
        await generateAndWriteSchema(contents, pathToFile);
        if (isBuild) {
          // Replace all occurrences of /static with ./static
          contents = contents.replace(/\/static/g, './static');
        }
        return {
          contents: `${contents};
          export { renderAsync } from 'htmldocs-module-that-will-export-render'
        `,
          loader: path.extname(pathToFile).slice(1) as Loader,
        };
      }
    );

    b.onResolve(
      { filter: /^htmldocs-module-that-will-export-render$/ },
      async (args) => {
        const options: ResolveOptions = {
          kind: "import-statement",
          importer: args.importer,
          resolveDir: args.resolveDir,
          namespace: args.namespace,
        };
        let result = await b.resolve("@htmldocs/render", options);
        if (result.errors.length === 0) {
          return result;
        }

        if (result.errors.length > 0 && result.errors[0]) {
          result.errors[0].text =
            "Failed trying to import `renderAsync` from `@htmldocs/render` to be able to render your document template.\n Maybe you don't have `@htmldocs/render` installed?";
        }
        return result;
      }
    );
  },
});

async function generateAndWriteSchema(contents: string, filePath: string): Promise<void> {
  const componentProps = await parseFileToProps(contents, filePath);
  const componentInterfaceName = `ComponentProps`;
  let interfaceContent = `export interface ${componentInterfaceName} {\n`;

  for (const propName in componentProps) {
    const prop = componentProps[propName];
    if (!prop || !prop.tsType) continue;
    const required = prop.required ? "" : "?";
    const tsType = "raw" in prop.tsType ? prop.tsType.raw : prop.tsType?.name;
    interfaceContent += `  ${propName}${required}: ${tsType};\n`;
  }

  interfaceContent += `}\n`;
  const fileContents = contents + "\n" + interfaceContent;
  const tempFilePath = createTempFilePath(filePath);

  await fs.writeFileSync(tempFilePath, fileContents);
  const config = {
    path: tempFilePath,
    tsconfig: process.env.NEXT_PUBLIC_USER_PROJECT_LOCATION + "/tsconfig.json",
    type: componentInterfaceName,
  };

  const schema = tsj.createGenerator(config).createSchema(config.type);
  fs.unlinkSync(tempFilePath);

  const schemaString = JSON.stringify(schema, null, 2);

  if (!fs.existsSync(DOCUMENT_SCHEMAS_DIR)) {
    fs.mkdirSync(DOCUMENT_SCHEMAS_DIR, { recursive: true });
  }
  const baseName = path.basename(filePath, path.extname(filePath));
  const schemaFilePath = path.join(
    DOCUMENT_SCHEMAS_DIR,
    baseName,
    `${baseName}.schema.json`
  );

  // Ensure the directory exists before writing
  fs.mkdirSync(path.dirname(schemaFilePath), { recursive: true });
  fs.writeFileSync(schemaFilePath, schemaString);
}

function createTempFilePath(filePath: string): string {
  const baseName = path.basename(filePath, path.extname(filePath));
  const dirName = path.dirname(filePath);
  const extension = path.extname(filePath).replace(".", "");
  const tempFileName = `.${baseName}.${extension}`;
  const tempFilePath = path.join(dirName, tempFileName);
  return tempFilePath;
}

const parseFileToProps = async (
  contents: string,
  filePath: string
): Promise<Documentation["props"] | undefined> => {
  const componentsInfo = parse(contents, {
    babelOptions: {
      filename: filePath,
      babelrc: false,
    },
  });

  if (componentsInfo.length > 0 && componentsInfo[0]) {
    return componentsInfo[0].props;
  } else {
    return undefined;
  }
};