react-native-flip/example/node_modules/react-native-web/dist/vendor/react-native/Animated/AnimatedEvent.js

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/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * 
 * @format
 */
'use strict';

import AnimatedValue from './nodes/AnimatedValue';
import NativeAnimatedHelper from './NativeAnimatedHelper';
import findNodeHandle from '../../../exports/findNodeHandle';
import invariant from 'fbjs/lib/invariant';
import { shouldUseNativeDriver } from './NativeAnimatedHelper';

var __DEV__ = process.env.NODE_ENV !== 'production';

export function attachNativeEvent(viewRef, eventName, argMapping) {
  // Find animated values in `argMapping` and create an array representing their
  // key path inside the `nativeEvent` object. Ex.: ['contentOffset', 'x'].
  var eventMappings = [];

  var traverse = function traverse(value, path) {
    if (value instanceof AnimatedValue) {
      value.__makeNative();

      eventMappings.push({
        nativeEventPath: path,
        animatedValueTag: value.__getNativeTag()
      });
    } else if (typeof value === 'object') {
      for (var _key in value) {
        traverse(value[_key], path.concat(_key));
      }
    }
  };

  invariant(argMapping[0] && argMapping[0].nativeEvent, 'Native driven events only support animated values contained inside `nativeEvent`.'); // Assume that the event containing `nativeEvent` is always the first argument.

  traverse(argMapping[0].nativeEvent, []);
  var viewTag = findNodeHandle(viewRef);

  if (viewTag != null) {
    eventMappings.forEach(function (mapping) {
      NativeAnimatedHelper.API.addAnimatedEventToView(viewTag, eventName, mapping);
    });
  }

  return {
    detach: function detach() {
      if (viewTag != null) {
        eventMappings.forEach(function (mapping) {
          NativeAnimatedHelper.API.removeAnimatedEventFromView(viewTag, eventName, // $FlowFixMe[incompatible-call]
          mapping.animatedValueTag);
        });
      }
    }
  };
}

function validateMapping(argMapping, args) {
  var validate = function validate(recMapping, recEvt, key) {
    if (recMapping instanceof AnimatedValue) {
      invariant(typeof recEvt === 'number', 'Bad mapping of event key ' + key + ', should be number but got ' + typeof recEvt);
      return;
    }

    if (typeof recEvt === 'number') {
      invariant(recMapping instanceof AnimatedValue, 'Bad mapping of type ' + typeof recMapping + ' for key ' + key + ', event value must map to AnimatedValue');
      return;
    }

    invariant(typeof recMapping === 'object', 'Bad mapping of type ' + typeof recMapping + ' for key ' + key);
    invariant(typeof recEvt === 'object', 'Bad event of type ' + typeof recEvt + ' for key ' + key);

    for (var mappingKey in recMapping) {
      validate(recMapping[mappingKey], recEvt[mappingKey], mappingKey);
    }
  };

  invariant(args.length >= argMapping.length, 'Event has less arguments than mapping');
  argMapping.forEach(function (mapping, idx) {
    validate(mapping, args[idx], 'arg' + idx);
  });
}

export var AnimatedEvent = /*#__PURE__*/function () {
  function AnimatedEvent(argMapping, config) {
    this._listeners = [];
    this._argMapping = argMapping;

    if (config == null) {
      console.warn('Animated.event now requires a second argument for options');
      config = {
        useNativeDriver: false
      };
    }

    if (config.listener) {
      this.__addListener(config.listener);
    }

    this._callListeners = this._callListeners.bind(this);
    this._attachedEvent = null;
    this.__isNative = shouldUseNativeDriver(config);
  }

  var _proto = AnimatedEvent.prototype;

  _proto.__addListener = function __addListener(callback) {
    this._listeners.push(callback);
  };

  _proto.__removeListener = function __removeListener(callback) {
    this._listeners = this._listeners.filter(function (listener) {
      return listener !== callback;
    });
  };

  _proto.__attach = function __attach(viewRef, eventName) {
    invariant(this.__isNative, 'Only native driven events need to be attached.');
    this._attachedEvent = attachNativeEvent(viewRef, eventName, this._argMapping);
  };

  _proto.__detach = function __detach(viewTag, eventName) {
    invariant(this.__isNative, 'Only native driven events need to be detached.');
    this._attachedEvent && this._attachedEvent.detach();
  };

  _proto.__getHandler = function __getHandler() {
    var _this = this;

    if (this.__isNative) {
      if (__DEV__) {
        var _validatedMapping = false;
        return function () {
          for (var _len = arguments.length, args = new Array(_len), _key2 = 0; _key2 < _len; _key2++) {
            args[_key2] = arguments[_key2];
          }

          if (!_validatedMapping) {
            validateMapping(_this._argMapping, args);
            _validatedMapping = true;
          }

          _this._callListeners.apply(_this, args);
        };
      } else {
        return this._callListeners;
      }
    }

    var validatedMapping = false;
    return function () {
      for (var _len2 = arguments.length, args = new Array(_len2), _key3 = 0; _key3 < _len2; _key3++) {
        args[_key3] = arguments[_key3];
      }

      if (__DEV__ && !validatedMapping) {
        validateMapping(_this._argMapping, args);
        validatedMapping = true;
      }

      var traverse = function traverse(recMapping, recEvt, key) {
        if (recMapping instanceof AnimatedValue) {
          if (typeof recEvt === 'number') {
            recMapping.setValue(recEvt);
          }
        } else if (typeof recMapping === 'object') {
          for (var mappingKey in recMapping) {
            /* $FlowFixMe(>=0.120.0) This comment suppresses an error found
             * when Flow v0.120 was deployed. To see the error, delete this
             * comment and run Flow. */
            traverse(recMapping[mappingKey], recEvt[mappingKey], mappingKey);
          }
        }
      };

      _this._argMapping.forEach(function (mapping, idx) {
        traverse(mapping, args[idx], 'arg' + idx);
      });

      _this._callListeners.apply(_this, args);
    };
  };

  _proto._callListeners = function _callListeners() {
    for (var _len3 = arguments.length, args = new Array(_len3), _key4 = 0; _key4 < _len3; _key4++) {
      args[_key4] = arguments[_key4];
    }

    this._listeners.forEach(function (listener) {
      return listener.apply(void 0, args);
    });
  };

  return AnimatedEvent;
}();