/* Converts

  export default class extends React.PureComponent {
    static displayName = 'Calendar';
    ...
  }

  to this:

  export default class Calendar extends React.PureComponent {
    ...
  }

  ----

  Usage:

  jscodeshift -d -p -t moveDisplayNameToClass.js <path>
*/

module.exports = function(file, api) {
  const j = api.jscodeshift;
  return j(file.source)
    .find(j.ClassExpression, { superClass: { object: { name: 'React' } } })
    .filter(p => {
      const firstBody = p.value.body.body[0];
      if (!firstBody) return false;
      return firstBody.key.name === 'displayName';
    })
    .replaceWith(p => {
      const displayName = p.value.body.body[0].value.value;
      const newBody = p.value.body;
      newBody.body = newBody.body.slice(1);

      return j.classExpression(
        j.identifier(displayName),
        newBody,
        p.value.superClass
      );
    })
    .toSource();
};