/*
 * Converts the given angular injected parameter into an explicit require statement
 *
 * Run this with jscodeshift
 * @example
 *     jscodeshift . --specifier='Auth' --source='application/Auth'
 *
 * Live demo: https://astexplorer.net/#/gist/5492d2b9850a451d8e8d532bc64f21ce/latest
 *
 * Converts:
 *     app.controller('myController', function ($scope, Auth, $q) {
 *     });
 *
 *     function test($scope, Auth, $q) {
 *       'ngInject';
 *     }
 *
 *     app.component('myComponent', {
 *       controller: function ($scope, Auth, $q) {
 *       }
 *     });
 *
 *     app.directive('myDirective', function (Auth) {
 *       return {
 *         controller: function ($scope, Auth, $q) {
 *         }
 *       };
 *     });
 *
 * to:
 *     import Auth from 'application/Auth';
 *     app.controller('myController', function ($scope, $q) {
 *     });
 *
 *     function test($scope, $q) {
 *       'ngInject';
 *     }
 *
 *     app.component('myComponent', {
 *       controller: function ($scope, $q) {
 *       }
 *     });
 *
 *     app.directive('myDirective', function () {
 *       return {
 *         controller: function ($scope, $q) {
 *         }
 *       };
 *     });
 */

const angularMethods = [
  'config',
  'provider',
  'factory',
  'service',
  'controller',
  'filter',
  'directive'
];

function isNgInject(functionExpression) {
  if (!functionExpression.body.body.length) {
    return false;
  }

  let firstBodyNode = functionExpression.body.body[0];

  return (
    firstBodyNode.type === 'ExpressionStatement' &&
    firstBodyNode.expression.type === 'Literal' &&
    firstBodyNode.expression.value === 'ngInject'
  );
}

function isControllerOnObject(path) {
  return (
    path.name === 'value' &&
    path.parentPath.parentPath.name === 'properties' &&
    path.node.type === 'FunctionExpression' &&
    path.parentPath.node.type === 'Property' &&
    path.parentPath.parentPath.node.type === 'ObjectExpression'
  );
}

function isParameterOfAngularMethod(path) {
  return (
    path.node.type === 'FunctionExpression' &&
    path.parentPath.name === 'arguments' &&
    path.parentPath.parentPath.node.type === 'CallExpression' &&
    path.parentPath.parentPath.node.callee.type === 'MemberExpression' &&
    path.parentPath.parentPath.node.callee.property.type === 'Identifier' &&
    angularMethods.indexOf(path.parentPath.parentPath.node.callee.property.name) > -1
  );
}

function isUseStrict(node) {
  return (
    node &&
    node.type === 'ExpressionStatement' &&
    node.expression.type === 'Literal' &&
    node.expression.value === 'use strict'
  );
}

module.exports = function transformer(file, api, options) {
  const j = api.jscodeshift;
  const {
    specifier = 'Auth',
    source = 'application/Auth'
  } = options;
  let addedImport = false;

  let output = j(file.source)
    .find(j.Identifier)
    .filter((path) => {
      return (
        path.node.name === specifier &&
        path.parentPath.name === 'params' && (
          isNgInject(path.parentPath.node) ||
          isControllerOnObject(path.parentPath.parentPath) ||
          isParameterOfAngularMethod(path.parentPath.parentPath)
        )
      );
    })
    .closest(j.Program)
    .forEach((path) => {
      let importDeclaration = j.importDeclaration([j.importDefaultSpecifier(j.identifier(specifier))], j.literal(source));
      if (isUseStrict(path.node.body[0])) {
        path.node.body.splice(1, 0, importDeclaration);
      }
      else {
        path.node.body.unshift(importDeclaration);
      }
      addedImport = true;
    })
    .toSource({
      arrowParensAlways: true,
      quote: 'single',
    });

  if (addedImport) {
    // Remove injections using regex to retain code style
    output = output.replace(new RegExp(`\\h*${specifier}\\s*,\\s*`, 'g'), '')
    .replace(new RegExp(`\\s*,\\s*${specifier}\\h*(?=[,\\n\\)])`, 'g'), '')
    .replace(new RegExp(`\\(\\s*${specifier}\\s*\\)`, 'g'), '()');
  }

  return output;
};