@difizen/mana-observable/es/observable.js

/* eslint-disable @typescript-eslint/no-explicit-any */
import { ObservableConfig } from "./config";
import { Notifiable } from "./notifiable";
import { Notifier } from "./notifier";
import { InstanceValue, ObservableProperties, Observability } from "./utils";
var propertyRelatedNotifier = Symbol('propertyRelatedNotifier');

// redefine observable properties
export function defineProperty(target, property, defaultValue) {
  var notifier = Notifier.getOrCreate(target, property);
  /**
   * notify notifier when property changed
   */
  var onChange = function onChange() {
    if (ObservableConfig.paused) {
      return;
    }
    Notifier.trigger(target, property);
  };
  /**
   * set observable property value and register onChange listener
   * @param value
   * @param notifier
   */
  var handleValue = function handleValue(value) {
    InstanceValue.set(target, property, value);
    if (notifier) {
      var last = Observability.getDisposable(propertyRelatedNotifier, notifier);
      if (last) {
        last.dispose();
      }
    }
    if (Notifiable.is(value)) {
      var valueNotifier = Notifiable.getNotifier(value);
      if (notifier && valueNotifier) {
        var toDispose = valueNotifier.onChangeSync(onChange);
        Observability.setDisposable(propertyRelatedNotifier, toDispose, notifier);
      }
    }
  };
  var initialValue = target[property] === undefined ? defaultValue : target[property];
  handleValue(Notifiable.transform(initialValue));
  // property getter
  var getter = function getter() {
    var value = Reflect.getMetadata(property, target);
    return value;
  };
  // property setter
  var setter = function setter(value) {
    var notifiableValue = Notifiable.transform(value);
    var oldValue = InstanceValue.get(target, property);
    if (notifiableValue !== oldValue) {
      handleValue(notifiableValue);
      onChange();
    }
  };
  // define property
  if (Reflect.deleteProperty(target, property)) {
    Reflect.defineProperty(target, property, {
      configurable: true,
      enumerable: true,
      get: getter,
      set: setter
    });
  }
  // mark observable property
  ObservableProperties.add(target, property);
  Observability.mark(target, property);
}
export function observable(target) {
  if (!Observability.canBeObservable(target)) {
    return target;
  }
  var origin = Observability.getOrigin(target);
  var properties = ObservableProperties.find(origin);
  if (!properties) {
    var notifiableValue = Notifiable.transform(origin);
    if (Notifiable.is(notifiableValue)) {
      Observability.mark(origin);
    }
    return notifiableValue;
  }
  properties.forEach(function (property) {
    return defineProperty(origin, property);
  });
  return origin;
}