import {set_from_array} from './utilities'
import {DEV} from './constants'

const react_properties_set = set_from_array([
  "constructor",
  "componentWillMount",
  "render",
  "componentDidMount",
  "componentWillReceiveProps",
  "shouldComponentUpdate",
  "componentWillUpdate",
  "componentDidUpdate",
  "componentWillUnmount",
])

const is_not_react_property = (property) => !react_properties_set[property]

// from react-autobind
function boundMethod(objPrototype, method, descriptor) {
  let fn = descriptor.value;

  return {
    configurable: true,
    get() {
      if (this === objPrototype || this.hasOwnProperty(method)) {
        return fn;
      }

      let boundFn = fn.bind(this);
      Object.defineProperty(this, method, {
        value: boundFn,
        configurable: true,
        writable: true
      });
      return boundFn;
    },
    set(new_fn) {
      fn = new_fn
    },
  };
}

export default function auto_bind(component) {
  let prototype = Object.getPrototypeOf(component)
  Object.getOwnPropertyNames(prototype)
  .filter(is_not_react_property)
  .forEach((property) => {
    let descriptor = Object.getOwnPropertyDescriptor(prototype, property)
    if (descriptor === undefined) {
      DEV && console.warn(`Autobind: "${method}" method not found in class.`)
      return
    }
    if (typeof descriptor.value !== 'function') {
      return
    }
    Object.defineProperty(prototype, property, boundMethod(prototype, property, descriptor))
  })
}