import * as CopyWebpackPlugin from 'copy-webpack-plugin';
import { normalizePath } from 'nx/src/utils/path';
import { basename, dirname, join, relative, resolve } from 'path';
import { statSync } from 'fs';

interface AssetGlobPattern {
  glob: string;
  input: string;
  output: string;
  ignore?: string[];
}

function normalizeAssets(
  assets: any[],
  root: string,
  sourceRoot: string
): AssetGlobPattern[] {
  return assets.map((asset) => {
    if (typeof asset === 'string') {
      const assetPath = normalizePath(asset);
      const resolvedAssetPath = resolve(root, assetPath);
      const resolvedSourceRoot = resolve(root, sourceRoot);

      if (!resolvedAssetPath.startsWith(resolvedSourceRoot)) {
        throw new Error(
          `The ${resolvedAssetPath} asset path must start with the project source root: ${sourceRoot}`
        );
      }

      const isDirectory = statSync(resolvedAssetPath).isDirectory();
      const input = isDirectory
        ? resolvedAssetPath
        : dirname(resolvedAssetPath);
      const output = relative(resolvedSourceRoot, resolve(root, input));
      const glob = isDirectory ? '**/*' : basename(resolvedAssetPath);
      return {
        input,
        output,
        glob,
      };
    } else {
      if (asset.output.startsWith('..')) {
        throw new Error(
          'An asset cannot be written to a location outside of the output path.'
        );
      }

      const assetPath = normalizePath(asset.input);
      const resolvedAssetPath = resolve(root, assetPath);
      return {
        ...asset,
        input: resolvedAssetPath,
        // Now we remove starting slash to make Webpack place it from the output root.
        output: asset.output.replace(/^\//, ''),
      };
    }
  });
}

export function createCopyPlugin(
  assets: any[],
  root: string,
  sourceRoot: string
) {
  return new CopyWebpackPlugin({
    patterns: normalizeAssets(assets, root, sourceRoot).map((asset) => {
      return {
        context: asset.input,
        to: join('../public', asset.output),
        from: asset.glob,
        globOptions: {
          ignore: [
            '.gitkeep',
            '**/.DS_Store',
            '**/Thumbs.db',
            ...(asset.ignore ?? []),
          ],
          dot: true,
        },
      };
    }),
  });
}