'use strict';

Object.defineProperty(exports, '__esModule', { value: true });

var proxyCompare = require('proxy-compare');

var isObject = function isObject(x) {
  return typeof x === 'object' && x !== null;
};

var refSet = new WeakSet();
var VERSION = process.env.NODE_ENV !== "production" ? Symbol('VERSION') : Symbol();
var LISTENERS = process.env.NODE_ENV !== "production" ? Symbol('LISTENERS') : Symbol();
var SNAPSHOT = process.env.NODE_ENV !== "production" ? Symbol('SNAPSHOT') : Symbol();

var buildProxyFunction = function buildProxyFunction(objectIs, newProxy, canProxy, PROMISE_RESULT, PROMISE_ERROR, snapshotCache, createSnapshot, proxyCache, versionHolder, proxyFunction) {
  if (objectIs === void 0) {
    objectIs = Object.is;
  }

  if (newProxy === void 0) {
    newProxy = function newProxy(target, handler) {
      return new Proxy(target, handler);
    };
  }

  if (canProxy === void 0) {
    canProxy = function canProxy(x) {
      return isObject(x) && !refSet.has(x) && (Array.isArray(x) || !(Symbol.iterator in x)) && !(x instanceof WeakMap) && !(x instanceof WeakSet) && !(x instanceof Error) && !(x instanceof Number) && !(x instanceof Date) && !(x instanceof String) && !(x instanceof RegExp) && !(x instanceof ArrayBuffer);
    };
  }

  if (PROMISE_RESULT === void 0) {
    PROMISE_RESULT = process.env.NODE_ENV !== "production" ? Symbol('PROMISE_RESULT') : Symbol();
  }

  if (PROMISE_ERROR === void 0) {
    PROMISE_ERROR = process.env.NODE_ENV !== "production" ? Symbol('PROMISE_ERROR') : Symbol();
  }

  if (snapshotCache === void 0) {
    snapshotCache = new WeakMap();
  }

  if (createSnapshot === void 0) {
    createSnapshot = function createSnapshot(version, target, receiver) {
      var cache = snapshotCache.get(receiver);

      if ((cache == null ? void 0 : cache[0]) === version) {
        return cache[1];
      }

      var snapshot = Array.isArray(target) ? [] : Object.create(Object.getPrototypeOf(target));
      proxyCompare.markToTrack(snapshot, true);
      snapshotCache.set(receiver, [version, snapshot]);
      Reflect.ownKeys(target).forEach(function (key) {
        var value = Reflect.get(target, key, receiver);

        if (refSet.has(value)) {
          proxyCompare.markToTrack(value, false);
          snapshot[key] = value;
        } else if (value instanceof Promise) {
          if (PROMISE_RESULT in value) {
            snapshot[key] = value[PROMISE_RESULT];
          } else {
            var errorOrPromise = value[PROMISE_ERROR] || value;
            Object.defineProperty(snapshot, key, {
              get: function get() {
                if (PROMISE_RESULT in value) {
                  return value[PROMISE_RESULT];
                }

                throw errorOrPromise;
              }
            });
          }
        } else if (value != null && value[LISTENERS]) {
          snapshot[key] = value[SNAPSHOT];
        } else {
          snapshot[key] = value;
        }
      });
      return Object.freeze(snapshot);
    };
  }

  if (proxyCache === void 0) {
    proxyCache = new WeakMap();
  }

  if (versionHolder === void 0) {
    versionHolder = [1];
  }

  if (proxyFunction === void 0) {
    proxyFunction = function proxyFunction(initialObject) {
      if (!isObject(initialObject)) {
        throw new Error('object required');
      }

      var found = proxyCache.get(initialObject);

      if (found) {
        return found;
      }

      var version = versionHolder[0];
      var listeners = new Set();

      var notifyUpdate = function notifyUpdate(op, nextVersion) {
        if (nextVersion === void 0) {
          nextVersion = ++versionHolder[0];
        }

        if (version !== nextVersion) {
          version = nextVersion;
          listeners.forEach(function (listener) {
            return listener(op, nextVersion);
          });
        }
      };

      var propListeners = new Map();

      var getPropListener = function getPropListener(prop) {
        var propListener = propListeners.get(prop);

        if (!propListener) {
          propListener = function propListener(op, nextVersion) {
            var newOp = [].concat(op);
            newOp[1] = [prop].concat(newOp[1]);
            notifyUpdate(newOp, nextVersion);
          };

          propListeners.set(prop, propListener);
        }

        return propListener;
      };

      var popPropListener = function popPropListener(prop) {
        var propListener = propListeners.get(prop);
        propListeners.delete(prop);
        return propListener;
      };

      var baseObject = Array.isArray(initialObject) ? [] : Object.create(Object.getPrototypeOf(initialObject));
      var handler = {
        get: function get(target, prop, receiver) {
          if (prop === VERSION) {
            return version;
          }

          if (prop === LISTENERS) {
            return listeners;
          }

          if (prop === SNAPSHOT) {
            return createSnapshot(version, target, receiver);
          }

          return Reflect.get(target, prop, receiver);
        },
        deleteProperty: function deleteProperty(target, prop) {
          var prevValue = Reflect.get(target, prop);
          var childListeners = prevValue == null ? void 0 : prevValue[LISTENERS];

          if (childListeners) {
            childListeners.delete(popPropListener(prop));
          }

          var deleted = Reflect.deleteProperty(target, prop);

          if (deleted) {
            notifyUpdate(['delete', [prop], prevValue]);
          }

          return deleted;
        },
        set: function set(target, prop, value, receiver) {
          var _Object$getOwnPropert, _value;

          var hasPrevValue = Reflect.has(target, prop);
          var prevValue = Reflect.get(target, prop, receiver);

          if (hasPrevValue && objectIs(prevValue, value)) {
            return true;
          }

          var childListeners = prevValue == null ? void 0 : prevValue[LISTENERS];

          if (childListeners) {
            childListeners.delete(popPropListener(prop));
          }

          if (isObject(value)) {
            value = proxyCompare.getUntracked(value) || value;
          }

          var nextValue;

          if ((_Object$getOwnPropert = Object.getOwnPropertyDescriptor(target, prop)) != null && _Object$getOwnPropert.set) {
            nextValue = value;
          } else if (value instanceof Promise) {
            nextValue = value.then(function (v) {
              nextValue[PROMISE_RESULT] = v;
              notifyUpdate(['resolve', [prop], v]);
              return v;
            }).catch(function (e) {
              nextValue[PROMISE_ERROR] = e;
              notifyUpdate(['reject', [prop], e]);
            });
          } else if ((_value = value) != null && _value[LISTENERS]) {
            nextValue = value;
            nextValue[LISTENERS].add(getPropListener(prop));
          } else if (canProxy(value)) {
            nextValue = proxy(value);
            nextValue[LISTENERS].add(getPropListener(prop));
          } else {
            nextValue = value;
          }

          Reflect.set(target, prop, nextValue, receiver);
          notifyUpdate(['set', [prop], value, prevValue]);
          return true;
        }
      };
      var proxyObject = newProxy(baseObject, handler);
      proxyCache.set(initialObject, proxyObject);
      Reflect.ownKeys(initialObject).forEach(function (key) {
        var desc = Object.getOwnPropertyDescriptor(initialObject, key);

        if (desc.get || desc.set) {
          Object.defineProperty(baseObject, key, desc);
        } else {
          proxyObject[key] = initialObject[key];
        }
      });
      return proxyObject;
    };
  }

  return [proxyFunction, refSet, VERSION, LISTENERS, SNAPSHOT, objectIs, newProxy, canProxy, PROMISE_RESULT, PROMISE_ERROR, snapshotCache, createSnapshot, proxyCache, versionHolder];
};

var _buildProxyFunction = buildProxyFunction(),
    proxyFunction = _buildProxyFunction[0];

function proxy(initialObject) {
  if (initialObject === void 0) {
    initialObject = {};
  }

  return proxyFunction(initialObject);
}
function getVersion(proxyObject) {
  return isObject(proxyObject) ? proxyObject[VERSION] : undefined;
}
function subscribe(proxyObject, callback, notifyInSync) {
  if (process.env.NODE_ENV !== "production" && !(proxyObject != null && proxyObject[LISTENERS])) {
    console.warn('Please use proxy object');
  }

  var promise;
  var ops = [];

  var listener = function listener(op) {
    ops.push(op);

    if (notifyInSync) {
      callback(ops.splice(0));
      return;
    }

    if (!promise) {
      promise = Promise.resolve().then(function () {
        promise = undefined;
        callback(ops.splice(0));
      });
    }
  };

  proxyObject[LISTENERS].add(listener);
  return function () {
    proxyObject[LISTENERS].delete(listener);
  };
}
function snapshot(proxyObject) {
  if (process.env.NODE_ENV !== "production" && !(proxyObject != null && proxyObject[SNAPSHOT])) {
    console.warn('Please use proxy object');
  }

  return proxyObject[SNAPSHOT];
}
function ref(obj) {
  refSet.add(obj);
  return obj;
}
var unstable_buildProxyFunction = buildProxyFunction;

exports.getVersion = getVersion;
exports.proxy = proxy;
exports.ref = ref;
exports.snapshot = snapshot;
exports.subscribe = subscribe;
exports.unstable_buildProxyFunction = unstable_buildProxyFunction;