import pkg from '../../package.json' with { type: 'json' };
import type { AbiExporterConfig, AbiExporterConfigEntry } from '../types.js';
import { Interface } from '@ethersproject/abi';
import {
  exists,
  getAllFilesMatching,
  readUtf8File,
  remove,
} from '@nomicfoundation/hardhat-utils/fs';
import type { HookContext } from 'hardhat/types/hooks';
import path from 'node:path';

const TS_TAG = `// this file was automatically generated by ${pkg.name} - do not modify`;

export const clearAbi = async (
  context: HookContext,
  configEntries: AbiExporterConfig,
) => {
  const entries = configEntries.filter((entry) => entry.clear);
  await Promise.all(entries.map((entry) => clearAbiGroup(context, entry)));
};

const clearAbiGroup = async (
  context: HookContext,
  config: AbiExporterConfigEntry,
) => {
  const outputDirectory = path.resolve(context.config.paths.root, config.path);

  if (!(await exists(outputDirectory))) {
    return;
  }

  // recursively get all relevant files from directory

  const jsonFiles = await getAllFilesMatching(
    outputDirectory,
    (absolutePathToFile) => path.extname(absolutePathToFile) === '.json',
  );

  const tsFiles = await getAllFilesMatching(
    outputDirectory,
    (absolutePathToFile) => path.extname(absolutePathToFile) === '.ts',
  );

  // validate file contents and delete

  await Promise.all(
    jsonFiles.map(async (file) => {
      const contents = await readUtf8File(file);

      try {
        // attempt to parse ABI from file contents
        new Interface(contents);
      } catch (e) {
        // file is not an ABI - do not delete
        return;
      }

      await remove(file);
    }),
  );

  await Promise.all(
    tsFiles.map(async (file) => {
      const contents = await readUtf8File(file);

      if (!contents.includes(TS_TAG)) {
        // file was not generated by plugin - do not delete
        return;
      }

      await remove(file);
    }),
  );

  // delete the directory if it's empty

  const remainingFiles = await getAllFilesMatching(outputDirectory);

  if (remainingFiles.length === 0) {
    await remove(outputDirectory);
  }
};