const glob = require('glob');
const {getOptions} = require('loader-utils');
const path = require('path');
const validateOptions = require('schema-utils');
const schema = {
  type: 'object',
  properties: {
    paths: {
      items: {
        type: 'string',
      },
      type: 'array',
    },
  },
  required: [
    'paths',
  ],
};

// Dynamically require all traits.
module.exports = function(source) {
  const options = getOptions(this);
  // Validate schema.
  validateOptions(schema, options, 'Avocado hooks');
  // Extract options.
  const {paths} = options;
  // Search avocado.
  const avocadoPath = path.normalize(
    path.join(__dirname, '..', '..'),
  );
  paths.push(avocadoPath);
  // Get source paths.
  const sourcePaths = [];
  paths.forEach((path) => {
    const files = glob.sync(`${path}/**/hooks.js`, {
      follow: true,
    });
    sourcePaths.push(...files);
  });
  // Build registers.
  const registers = sourcePaths.map((sourcePath) => {
    const relativePath = path.relative(__dirname, sourcePath);
    const basename = path.basename(relativePath, '.js');
    const parts = relativePath.split('/');
    // Chop off basename.
    parts.pop();
    // Module or local?
    let importDirectory;
    if ('..' === parts[0]) {
      const avocadoPathParts = ['@avocado', 'core', 'hook'].concat(parts);
      importDirectory = path.normalize(avocadoPathParts.join('/'));
    }
    else if ('node_modules' === parts[0]) {
      importDirectory = parts.slice(1).join('/');
    }
    else {
      importDirectory = `./${parts.join('/')}`;
    }
    // Register hooks.
    const importPath = `${importDirectory}/hooks`;
    return [
      `registerHooks('${importDirectory}', require('${importPath}'));`,
    ].join('\n');
  });
  // Import trait registry first.
  const output = [
    `import {registerHooks} from '@avocado/core/hook/registry'`,
    '',
    ...registers
  ].join('\n');
  return output;
}