/*
Stimulus 2.0.0
Copyright © 2020 Basecamp, LLC
 */
class EventListener {
  constructor(eventTarget, eventName, eventOptions) {
    this.eventTarget = eventTarget;
    this.eventName = eventName;
    this.eventOptions = eventOptions;
    this.unorderedBindings = new Set;
  }
  connect() {
    this.eventTarget.addEventListener(this.eventName, this, this.eventOptions);
  }
  disconnect() {
    this.eventTarget.removeEventListener(this.eventName, this, this.eventOptions);
  }
  bindingConnected(binding) {
    this.unorderedBindings.add(binding);
  }
  bindingDisconnected(binding) {
    this.unorderedBindings.delete(binding);
  }
  handleEvent(event) {
    const extendedEvent = extendEvent(event);
    for (const binding of this.bindings) {
      if (extendedEvent.immediatePropagationStopped) {
        break;
      } else {
        binding.handleEvent(extendedEvent);
      }
    }
  }
  get bindings() {
    return Array.from(this.unorderedBindings).sort(((left, right) => {
      const leftIndex = left.index, rightIndex = right.index;
      return leftIndex < rightIndex ? -1 : leftIndex > rightIndex ? 1 : 0;
    }));
  }
}

function extendEvent(event) {
  if ("immediatePropagationStopped" in event) {
    return event;
  } else {
    const {stopImmediatePropagation: stopImmediatePropagation} = event;
    return Object.assign(event, {
      immediatePropagationStopped: false,
      stopImmediatePropagation() {
        this.immediatePropagationStopped = true;
        stopImmediatePropagation.call(this);
      }
    });
  }
}

class Dispatcher {
  constructor(application) {
    this.application = application;
    this.eventListenerMaps = new Map;
    this.started = false;
  }
  start() {
    if (!this.started) {
      this.started = true;
      this.eventListeners.forEach((eventListener => eventListener.connect()));
    }
  }
  stop() {
    if (this.started) {
      this.started = false;
      this.eventListeners.forEach((eventListener => eventListener.disconnect()));
    }
  }
  get eventListeners() {
    return Array.from(this.eventListenerMaps.values()).reduce(((listeners, map) => listeners.concat(Array.from(map.values()))), []);
  }
  bindingConnected(binding) {
    this.fetchEventListenerForBinding(binding).bindingConnected(binding);
  }
  bindingDisconnected(binding) {
    this.fetchEventListenerForBinding(binding).bindingDisconnected(binding);
  }
  handleError(error, message, detail = {}) {
    this.application.handleError(error, `Error ${message}`, detail);
  }
  fetchEventListenerForBinding(binding) {
    const {eventTarget: eventTarget, eventName: eventName, eventOptions: eventOptions} = binding;
    return this.fetchEventListener(eventTarget, eventName, eventOptions);
  }
  fetchEventListener(eventTarget, eventName, eventOptions) {
    const eventListenerMap = this.fetchEventListenerMapForEventTarget(eventTarget);
    const cacheKey = this.cacheKey(eventName, eventOptions);
    let eventListener = eventListenerMap.get(cacheKey);
    if (!eventListener) {
      eventListener = this.createEventListener(eventTarget, eventName, eventOptions);
      eventListenerMap.set(cacheKey, eventListener);
    }
    return eventListener;
  }
  createEventListener(eventTarget, eventName, eventOptions) {
    const eventListener = new EventListener(eventTarget, eventName, eventOptions);
    if (this.started) {
      eventListener.connect();
    }
    return eventListener;
  }
  fetchEventListenerMapForEventTarget(eventTarget) {
    let eventListenerMap = this.eventListenerMaps.get(eventTarget);
    if (!eventListenerMap) {
      eventListenerMap = new Map;
      this.eventListenerMaps.set(eventTarget, eventListenerMap);
    }
    return eventListenerMap;
  }
  cacheKey(eventName, eventOptions) {
    const parts = [ eventName ];
    Object.keys(eventOptions).sort().forEach((key => {
      parts.push(`${eventOptions[key] ? "" : "!"}${key}`);
    }));
    return parts.join(":");
  }
}

const descriptorPattern = /^((.+?)(@(window|document))?->)?(.+?)(#([^:]+?))(:(.+))?$/;

function parseActionDescriptorString(descriptorString) {
  const source = descriptorString.trim();
  const matches = source.match(descriptorPattern) || [];
  return {
    eventTarget: parseEventTarget(matches[4]),
    eventName: matches[2],
    eventOptions: matches[9] ? parseEventOptions(matches[9]) : {},
    identifier: matches[5],
    methodName: matches[7]
  };
}

function parseEventTarget(eventTargetName) {
  if (eventTargetName == "window") {
    return window;
  } else if (eventTargetName == "document") {
    return document;
  }
}

function parseEventOptions(eventOptions) {
  return eventOptions.split(":").reduce(((options, token) => Object.assign(options, {
    [token.replace(/^!/, "")]: !/^!/.test(token)
  })), {});
}

function stringifyEventTarget(eventTarget) {
  if (eventTarget == window) {
    return "window";
  } else if (eventTarget == document) {
    return "document";
  }
}

class Action {
  constructor(element, index, descriptor) {
    this.element = element;
    this.index = index;
    this.eventTarget = descriptor.eventTarget || element;
    this.eventName = descriptor.eventName || getDefaultEventNameForElement(element) || error("missing event name");
    this.eventOptions = descriptor.eventOptions || {};
    this.identifier = descriptor.identifier || error("missing identifier");
    this.methodName = descriptor.methodName || error("missing method name");
  }
  static forToken(token) {
    return new this(token.element, token.index, parseActionDescriptorString(token.content));
  }
  toString() {
    const eventNameSuffix = this.eventTargetName ? `@${this.eventTargetName}` : "";
    return `${this.eventName}${eventNameSuffix}->${this.identifier}#${this.methodName}`;
  }
  get eventTargetName() {
    return stringifyEventTarget(this.eventTarget);
  }
}

const defaultEventNames = {
  a: e => "click",
  button: e => "click",
  form: e => "submit",
  input: e => e.getAttribute("type") == "submit" ? "click" : "input",
  select: e => "change",
  textarea: e => "input"
};

function getDefaultEventNameForElement(element) {
  const tagName = element.tagName.toLowerCase();
  if (tagName in defaultEventNames) {
    return defaultEventNames[tagName](element);
  }
}

function error(message) {
  throw new Error(message);
}

class Binding {
  constructor(context, action) {
    this.context = context;
    this.action = action;
  }
  get index() {
    return this.action.index;
  }
  get eventTarget() {
    return this.action.eventTarget;
  }
  get eventOptions() {
    return this.action.eventOptions;
  }
  get identifier() {
    return this.context.identifier;
  }
  handleEvent(event) {
    if (this.willBeInvokedByEvent(event)) {
      this.invokeWithEvent(event);
    }
  }
  get eventName() {
    return this.action.eventName;
  }
  get method() {
    const method = this.controller[this.methodName];
    if (typeof method == "function") {
      return method;
    }
    throw new Error(`Action "${this.action}" references undefined method "${this.methodName}"`);
  }
  invokeWithEvent(event) {
    try {
      this.method.call(this.controller, event);
    } catch (error) {
      const {identifier: identifier, controller: controller, element: element, index: index} = this;
      const detail = {
        identifier: identifier,
        controller: controller,
        element: element,
        index: index,
        event: event
      };
      this.context.handleError(error, `invoking action "${this.action}"`, detail);
    }
  }
  willBeInvokedByEvent(event) {
    const eventTarget = event.target;
    if (this.element === eventTarget) {
      return true;
    } else if (eventTarget instanceof Element && this.element.contains(eventTarget)) {
      return this.scope.containsElement(eventTarget);
    } else {
      return this.scope.containsElement(this.action.element);
    }
  }
  get controller() {
    return this.context.controller;
  }
  get methodName() {
    return this.action.methodName;
  }
  get element() {
    return this.scope.element;
  }
  get scope() {
    return this.context.scope;
  }
}

class ElementObserver {
  constructor(element, delegate) {
    this.element = element;
    this.started = false;
    this.delegate = delegate;
    this.elements = new Set;
    this.mutationObserver = new MutationObserver((mutations => this.processMutations(mutations)));
  }
  start() {
    if (!this.started) {
      this.started = true;
      this.mutationObserver.observe(this.element, {
        attributes: true,
        childList: true,
        subtree: true
      });
      this.refresh();
    }
  }
  stop() {
    if (this.started) {
      this.mutationObserver.takeRecords();
      this.mutationObserver.disconnect();
      this.started = false;
    }
  }
  refresh() {
    if (this.started) {
      const matches = new Set(this.matchElementsInTree());
      for (const element of Array.from(this.elements)) {
        if (!matches.has(element)) {
          this.removeElement(element);
        }
      }
      for (const element of Array.from(matches)) {
        this.addElement(element);
      }
    }
  }
  processMutations(mutations) {
    if (this.started) {
      for (const mutation of mutations) {
        this.processMutation(mutation);
      }
    }
  }
  processMutation(mutation) {
    if (mutation.type == "attributes") {
      this.processAttributeChange(mutation.target, mutation.attributeName);
    } else if (mutation.type == "childList") {
      this.processRemovedNodes(mutation.removedNodes);
      this.processAddedNodes(mutation.addedNodes);
    }
  }
  processAttributeChange(node, attributeName) {
    const element = node;
    if (this.elements.has(element)) {
      if (this.delegate.elementAttributeChanged && this.matchElement(element)) {
        this.delegate.elementAttributeChanged(element, attributeName);
      } else {
        this.removeElement(element);
      }
    } else if (this.matchElement(element)) {
      this.addElement(element);
    }
  }
  processRemovedNodes(nodes) {
    for (const node of Array.from(nodes)) {
      const element = this.elementFromNode(node);
      if (element) {
        this.processTree(element, this.removeElement);
      }
    }
  }
  processAddedNodes(nodes) {
    for (const node of Array.from(nodes)) {
      const element = this.elementFromNode(node);
      if (element && this.elementIsActive(element)) {
        this.processTree(element, this.addElement);
      }
    }
  }
  matchElement(element) {
    return this.delegate.matchElement(element);
  }
  matchElementsInTree(tree = this.element) {
    return this.delegate.matchElementsInTree(tree);
  }
  processTree(tree, processor) {
    for (const element of this.matchElementsInTree(tree)) {
      processor.call(this, element);
    }
  }
  elementFromNode(node) {
    if (node.nodeType == Node.ELEMENT_NODE) {
      return node;
    }
  }
  elementIsActive(element) {
    if (element.isConnected != this.element.isConnected) {
      return false;
    } else {
      return this.element.contains(element);
    }
  }
  addElement(element) {
    if (!this.elements.has(element)) {
      if (this.elementIsActive(element)) {
        this.elements.add(element);
        if (this.delegate.elementMatched) {
          this.delegate.elementMatched(element);
        }
      }
    }
  }
  removeElement(element) {
    if (this.elements.has(element)) {
      this.elements.delete(element);
      if (this.delegate.elementUnmatched) {
        this.delegate.elementUnmatched(element);
      }
    }
  }
}

class AttributeObserver {
  constructor(element, attributeName, delegate) {
    this.attributeName = attributeName;
    this.delegate = delegate;
    this.elementObserver = new ElementObserver(element, this);
  }
  get element() {
    return this.elementObserver.element;
  }
  get selector() {
    return `[${this.attributeName}]`;
  }
  start() {
    this.elementObserver.start();
  }
  stop() {
    this.elementObserver.stop();
  }
  refresh() {
    this.elementObserver.refresh();
  }
  get started() {
    return this.elementObserver.started;
  }
  matchElement(element) {
    return element.hasAttribute(this.attributeName);
  }
  matchElementsInTree(tree) {
    const match = this.matchElement(tree) ? [ tree ] : [];
    const matches = Array.from(tree.querySelectorAll(this.selector));
    return match.concat(matches);
  }
  elementMatched(element) {
    if (this.delegate.elementMatchedAttribute) {
      this.delegate.elementMatchedAttribute(element, this.attributeName);
    }
  }
  elementUnmatched(element) {
    if (this.delegate.elementUnmatchedAttribute) {
      this.delegate.elementUnmatchedAttribute(element, this.attributeName);
    }
  }
  elementAttributeChanged(element, attributeName) {
    if (this.delegate.elementAttributeValueChanged && this.attributeName == attributeName) {
      this.delegate.elementAttributeValueChanged(element, attributeName);
    }
  }
}

class StringMapObserver {
  constructor(element, delegate) {
    this.element = element;
    this.delegate = delegate;
    this.started = false;
    this.stringMap = new Map;
    this.mutationObserver = new MutationObserver((mutations => this.processMutations(mutations)));
  }
  start() {
    if (!this.started) {
      this.started = true;
      this.mutationObserver.observe(this.element, {
        attributes: true
      });
      this.refresh();
    }
  }
  stop() {
    if (this.started) {
      this.mutationObserver.takeRecords();
      this.mutationObserver.disconnect();
      this.started = false;
    }
  }
  refresh() {
    if (this.started) {
      for (const attributeName of this.knownAttributeNames) {
        this.refreshAttribute(attributeName);
      }
    }
  }
  processMutations(mutations) {
    if (this.started) {
      for (const mutation of mutations) {
        this.processMutation(mutation);
      }
    }
  }
  processMutation(mutation) {
    const attributeName = mutation.attributeName;
    if (attributeName) {
      this.refreshAttribute(attributeName);
    }
  }
  refreshAttribute(attributeName) {
    const key = this.delegate.getStringMapKeyForAttribute(attributeName);
    if (key != null) {
      if (!this.stringMap.has(attributeName)) {
        this.stringMapKeyAdded(key, attributeName);
      }
      const value = this.element.getAttribute(attributeName);
      if (this.stringMap.get(attributeName) != value) {
        this.stringMapValueChanged(value, key);
      }
      if (value == null) {
        this.stringMap.delete(attributeName);
        this.stringMapKeyRemoved(key, attributeName);
      } else {
        this.stringMap.set(attributeName, value);
      }
    }
  }
  stringMapKeyAdded(key, attributeName) {
    if (this.delegate.stringMapKeyAdded) {
      this.delegate.stringMapKeyAdded(key, attributeName);
    }
  }
  stringMapValueChanged(value, key) {
    if (this.delegate.stringMapValueChanged) {
      this.delegate.stringMapValueChanged(value, key);
    }
  }
  stringMapKeyRemoved(key, attributeName) {
    if (this.delegate.stringMapKeyRemoved) {
      this.delegate.stringMapKeyRemoved(key, attributeName);
    }
  }
  get knownAttributeNames() {
    return Array.from(new Set(this.currentAttributeNames.concat(this.recordedAttributeNames)));
  }
  get currentAttributeNames() {
    return Array.from(this.element.attributes).map((attribute => attribute.name));
  }
  get recordedAttributeNames() {
    return Array.from(this.stringMap.keys());
  }
}

function add(map, key, value) {
  fetch(map, key).add(value);
}

function del(map, key, value) {
  fetch(map, key).delete(value);
  prune(map, key);
}

function fetch(map, key) {
  let values = map.get(key);
  if (!values) {
    values = new Set;
    map.set(key, values);
  }
  return values;
}

function prune(map, key) {
  const values = map.get(key);
  if (values != null && values.size == 0) {
    map.delete(key);
  }
}

class Multimap {
  constructor() {
    this.valuesByKey = new Map;
  }
  get values() {
    const sets = Array.from(this.valuesByKey.values());
    return sets.reduce(((values, set) => values.concat(Array.from(set))), []);
  }
  get size() {
    const sets = Array.from(this.valuesByKey.values());
    return sets.reduce(((size, set) => size + set.size), 0);
  }
  add(key, value) {
    add(this.valuesByKey, key, value);
  }
  delete(key, value) {
    del(this.valuesByKey, key, value);
  }
  has(key, value) {
    const values = this.valuesByKey.get(key);
    return values != null && values.has(value);
  }
  hasKey(key) {
    return this.valuesByKey.has(key);
  }
  hasValue(value) {
    const sets = Array.from(this.valuesByKey.values());
    return sets.some((set => set.has(value)));
  }
  getValuesForKey(key) {
    const values = this.valuesByKey.get(key);
    return values ? Array.from(values) : [];
  }
  getKeysForValue(value) {
    return Array.from(this.valuesByKey).filter((([key, values]) => values.has(value))).map((([key, values]) => key));
  }
}

class TokenListObserver {
  constructor(element, attributeName, delegate) {
    this.attributeObserver = new AttributeObserver(element, attributeName, this);
    this.delegate = delegate;
    this.tokensByElement = new Multimap;
  }
  get started() {
    return this.attributeObserver.started;
  }
  start() {
    this.attributeObserver.start();
  }
  stop() {
    this.attributeObserver.stop();
  }
  refresh() {
    this.attributeObserver.refresh();
  }
  get element() {
    return this.attributeObserver.element;
  }
  get attributeName() {
    return this.attributeObserver.attributeName;
  }
  elementMatchedAttribute(element) {
    this.tokensMatched(this.readTokensForElement(element));
  }
  elementAttributeValueChanged(element) {
    const [unmatchedTokens, matchedTokens] = this.refreshTokensForElement(element);
    this.tokensUnmatched(unmatchedTokens);
    this.tokensMatched(matchedTokens);
  }
  elementUnmatchedAttribute(element) {
    this.tokensUnmatched(this.tokensByElement.getValuesForKey(element));
  }
  tokensMatched(tokens) {
    tokens.forEach((token => this.tokenMatched(token)));
  }
  tokensUnmatched(tokens) {
    tokens.forEach((token => this.tokenUnmatched(token)));
  }
  tokenMatched(token) {
    this.delegate.tokenMatched(token);
    this.tokensByElement.add(token.element, token);
  }
  tokenUnmatched(token) {
    this.delegate.tokenUnmatched(token);
    this.tokensByElement.delete(token.element, token);
  }
  refreshTokensForElement(element) {
    const previousTokens = this.tokensByElement.getValuesForKey(element);
    const currentTokens = this.readTokensForElement(element);
    const firstDifferingIndex = zip(previousTokens, currentTokens).findIndex((([previousToken, currentToken]) => !tokensAreEqual(previousToken, currentToken)));
    if (firstDifferingIndex == -1) {
      return [ [], [] ];
    } else {
      return [ previousTokens.slice(firstDifferingIndex), currentTokens.slice(firstDifferingIndex) ];
    }
  }
  readTokensForElement(element) {
    const attributeName = this.attributeName;
    const tokenString = element.getAttribute(attributeName) || "";
    return parseTokenString(tokenString, element, attributeName);
  }
}

function parseTokenString(tokenString, element, attributeName) {
  return tokenString.trim().split(/\s+/).filter((content => content.length)).map(((content, index) => ({
    element: element,
    attributeName: attributeName,
    content: content,
    index: index
  })));
}

function zip(left, right) {
  const length = Math.max(left.length, right.length);
  return Array.from({
    length: length
  }, ((_, index) => [ left[index], right[index] ]));
}

function tokensAreEqual(left, right) {
  return left && right && left.index == right.index && left.content == right.content;
}

class ValueListObserver {
  constructor(element, attributeName, delegate) {
    this.tokenListObserver = new TokenListObserver(element, attributeName, this);
    this.delegate = delegate;
    this.parseResultsByToken = new WeakMap;
    this.valuesByTokenByElement = new WeakMap;
  }
  get started() {
    return this.tokenListObserver.started;
  }
  start() {
    this.tokenListObserver.start();
  }
  stop() {
    this.tokenListObserver.stop();
  }
  refresh() {
    this.tokenListObserver.refresh();
  }
  get element() {
    return this.tokenListObserver.element;
  }
  get attributeName() {
    return this.tokenListObserver.attributeName;
  }
  tokenMatched(token) {
    const {element: element} = token;
    const {value: value} = this.fetchParseResultForToken(token);
    if (value) {
      this.fetchValuesByTokenForElement(element).set(token, value);
      this.delegate.elementMatchedValue(element, value);
    }
  }
  tokenUnmatched(token) {
    const {element: element} = token;
    const {value: value} = this.fetchParseResultForToken(token);
    if (value) {
      this.fetchValuesByTokenForElement(element).delete(token);
      this.delegate.elementUnmatchedValue(element, value);
    }
  }
  fetchParseResultForToken(token) {
    let parseResult = this.parseResultsByToken.get(token);
    if (!parseResult) {
      parseResult = this.parseToken(token);
      this.parseResultsByToken.set(token, parseResult);
    }
    return parseResult;
  }
  fetchValuesByTokenForElement(element) {
    let valuesByToken = this.valuesByTokenByElement.get(element);
    if (!valuesByToken) {
      valuesByToken = new Map;
      this.valuesByTokenByElement.set(element, valuesByToken);
    }
    return valuesByToken;
  }
  parseToken(token) {
    try {
      const value = this.delegate.parseValueForToken(token);
      return {
        value: value
      };
    } catch (error) {
      return {
        error: error
      };
    }
  }
}

class BindingObserver {
  constructor(context, delegate) {
    this.context = context;
    this.delegate = delegate;
    this.bindingsByAction = new Map;
  }
  start() {
    if (!this.valueListObserver) {
      this.valueListObserver = new ValueListObserver(this.element, this.actionAttribute, this);
      this.valueListObserver.start();
    }
  }
  stop() {
    if (this.valueListObserver) {
      this.valueListObserver.stop();
      delete this.valueListObserver;
      this.disconnectAllActions();
    }
  }
  get element() {
    return this.context.element;
  }
  get identifier() {
    return this.context.identifier;
  }
  get actionAttribute() {
    return this.schema.actionAttribute;
  }
  get schema() {
    return this.context.schema;
  }
  get bindings() {
    return Array.from(this.bindingsByAction.values());
  }
  connectAction(action) {
    const binding = new Binding(this.context, action);
    this.bindingsByAction.set(action, binding);
    this.delegate.bindingConnected(binding);
  }
  disconnectAction(action) {
    const binding = this.bindingsByAction.get(action);
    if (binding) {
      this.bindingsByAction.delete(action);
      this.delegate.bindingDisconnected(binding);
    }
  }
  disconnectAllActions() {
    this.bindings.forEach((binding => this.delegate.bindingDisconnected(binding)));
    this.bindingsByAction.clear();
  }
  parseValueForToken(token) {
    const action = Action.forToken(token);
    if (action.identifier == this.identifier) {
      return action;
    }
  }
  elementMatchedValue(element, action) {
    this.connectAction(action);
  }
  elementUnmatchedValue(element, action) {
    this.disconnectAction(action);
  }
}

class ValueObserver {
  constructor(context, receiver) {
    this.context = context;
    this.receiver = receiver;
    this.stringMapObserver = new StringMapObserver(this.element, this);
    this.valueDescriptorMap = this.controller.valueDescriptorMap;
    this.invokeChangedCallbacksForDefaultValues();
  }
  start() {
    this.stringMapObserver.start();
  }
  stop() {
    this.stringMapObserver.stop();
  }
  get element() {
    return this.context.element;
  }
  get controller() {
    return this.context.controller;
  }
  getStringMapKeyForAttribute(attributeName) {
    if (attributeName in this.valueDescriptorMap) {
      return this.valueDescriptorMap[attributeName].name;
    }
  }
  stringMapValueChanged(attributeValue, name) {
    this.invokeChangedCallbackForValue(name);
  }
  invokeChangedCallbacksForDefaultValues() {
    for (const {key: key, name: name, defaultValue: defaultValue} of this.valueDescriptors) {
      if (defaultValue != undefined && !this.controller.data.has(key)) {
        this.invokeChangedCallbackForValue(name);
      }
    }
  }
  invokeChangedCallbackForValue(name) {
    const methodName = `${name}Changed`;
    const method = this.receiver[methodName];
    if (typeof method == "function") {
      const value = this.receiver[name];
      method.call(this.receiver, value);
    }
  }
  get valueDescriptors() {
    const {valueDescriptorMap: valueDescriptorMap} = this;
    return Object.keys(valueDescriptorMap).map((key => valueDescriptorMap[key]));
  }
}

class Context {
  constructor(module, scope) {
    this.module = module;
    this.scope = scope;
    this.controller = new module.controllerConstructor(this);
    this.bindingObserver = new BindingObserver(this, this.dispatcher);
    this.valueObserver = new ValueObserver(this, this.controller);
    try {
      this.controller.initialize();
    } catch (error) {
      this.handleError(error, "initializing controller");
    }
  }
  connect() {
    this.bindingObserver.start();
    this.valueObserver.start();
    try {
      this.controller.connect();
    } catch (error) {
      this.handleError(error, "connecting controller");
    }
  }
  disconnect() {
    try {
      this.controller.disconnect();
    } catch (error) {
      this.handleError(error, "disconnecting controller");
    }
    this.valueObserver.stop();
    this.bindingObserver.stop();
  }
  get application() {
    return this.module.application;
  }
  get identifier() {
    return this.module.identifier;
  }
  get schema() {
    return this.application.schema;
  }
  get dispatcher() {
    return this.application.dispatcher;
  }
  get element() {
    return this.scope.element;
  }
  get parentElement() {
    return this.element.parentElement;
  }
  handleError(error, message, detail = {}) {
    const {identifier: identifier, controller: controller, element: element} = this;
    detail = Object.assign({
      identifier: identifier,
      controller: controller,
      element: element
    }, detail);
    this.application.handleError(error, `Error ${message}`, detail);
  }
}

function readInheritableStaticArrayValues(constructor, propertyName) {
  const ancestors = getAncestorsForConstructor(constructor);
  return Array.from(ancestors.reduce(((values, constructor) => {
    getOwnStaticArrayValues(constructor, propertyName).forEach((name => values.add(name)));
    return values;
  }), new Set));
}

function readInheritableStaticObjectPairs(constructor, propertyName) {
  const ancestors = getAncestorsForConstructor(constructor);
  return ancestors.reduce(((pairs, constructor) => {
    pairs.push(...getOwnStaticObjectPairs(constructor, propertyName));
    return pairs;
  }), []);
}

function getAncestorsForConstructor(constructor) {
  const ancestors = [];
  while (constructor) {
    ancestors.push(constructor);
    constructor = Object.getPrototypeOf(constructor);
  }
  return ancestors.reverse();
}

function getOwnStaticArrayValues(constructor, propertyName) {
  const definition = constructor[propertyName];
  return Array.isArray(definition) ? definition : [];
}

function getOwnStaticObjectPairs(constructor, propertyName) {
  const definition = constructor[propertyName];
  return definition ? Object.keys(definition).map((key => [ key, definition[key] ])) : [];
}

function bless(constructor) {
  return shadow(constructor, getBlessedProperties(constructor));
}

function shadow(constructor, properties) {
  const shadowConstructor = extend(constructor);
  const shadowProperties = getShadowProperties(constructor.prototype, properties);
  Object.defineProperties(shadowConstructor.prototype, shadowProperties);
  return shadowConstructor;
}

function getBlessedProperties(constructor) {
  const blessings = readInheritableStaticArrayValues(constructor, "blessings");
  return blessings.reduce(((blessedProperties, blessing) => {
    const properties = blessing(constructor);
    for (const key in properties) {
      const descriptor = blessedProperties[key] || {};
      blessedProperties[key] = Object.assign(descriptor, properties[key]);
    }
    return blessedProperties;
  }), {});
}

function getShadowProperties(prototype, properties) {
  return getOwnKeys(properties).reduce(((shadowProperties, key) => {
    const descriptor = getShadowedDescriptor(prototype, properties, key);
    if (descriptor) {
      Object.assign(shadowProperties, {
        [key]: descriptor
      });
    }
    return shadowProperties;
  }), {});
}

function getShadowedDescriptor(prototype, properties, key) {
  const shadowingDescriptor = Object.getOwnPropertyDescriptor(prototype, key);
  const shadowedByValue = shadowingDescriptor && "value" in shadowingDescriptor;
  if (!shadowedByValue) {
    const descriptor = Object.getOwnPropertyDescriptor(properties, key).value;
    if (shadowingDescriptor) {
      descriptor.get = shadowingDescriptor.get || descriptor.get;
      descriptor.set = shadowingDescriptor.set || descriptor.set;
    }
    return descriptor;
  }
}

const getOwnKeys = (() => {
  if (typeof Object.getOwnPropertySymbols == "function") {
    return object => [ ...Object.getOwnPropertyNames(object), ...Object.getOwnPropertySymbols(object) ];
  } else {
    return Object.getOwnPropertyNames;
  }
})();

const extend = (() => {
  function extendWithReflect(constructor) {
    function extended() {
      return Reflect.construct(constructor, arguments, new.target);
    }
    extended.prototype = Object.create(constructor.prototype, {
      constructor: {
        value: extended
      }
    });
    Reflect.setPrototypeOf(extended, constructor);
    return extended;
  }
  function testReflectExtension() {
    const a = function() {
      this.a.call(this);
    };
    const b = extendWithReflect(a);
    b.prototype.a = function() {};
    return new b;
  }
  try {
    testReflectExtension();
    return extendWithReflect;
  } catch (error) {
    return constructor => class extended extends constructor {};
  }
})();

function blessDefinition(definition) {
  return {
    identifier: definition.identifier,
    controllerConstructor: bless(definition.controllerConstructor)
  };
}

class Module {
  constructor(application, definition) {
    this.application = application;
    this.definition = blessDefinition(definition);
    this.contextsByScope = new WeakMap;
    this.connectedContexts = new Set;
  }
  get identifier() {
    return this.definition.identifier;
  }
  get controllerConstructor() {
    return this.definition.controllerConstructor;
  }
  get contexts() {
    return Array.from(this.connectedContexts);
  }
  connectContextForScope(scope) {
    const context = this.fetchContextForScope(scope);
    this.connectedContexts.add(context);
    context.connect();
  }
  disconnectContextForScope(scope) {
    const context = this.contextsByScope.get(scope);
    if (context) {
      this.connectedContexts.delete(context);
      context.disconnect();
    }
  }
  fetchContextForScope(scope) {
    let context = this.contextsByScope.get(scope);
    if (!context) {
      context = new Context(this, scope);
      this.contextsByScope.set(scope, context);
    }
    return context;
  }
}

class ClassMap {
  constructor(scope) {
    this.scope = scope;
  }
  has(name) {
    return this.data.has(this.getDataKey(name));
  }
  get(name) {
    return this.data.get(this.getDataKey(name));
  }
  getAttributeName(name) {
    return this.data.getAttributeNameForKey(this.getDataKey(name));
  }
  getDataKey(name) {
    return `${name}-class`;
  }
  get data() {
    return this.scope.data;
  }
}

function camelize(value) {
  return value.replace(/(?:[_-])([a-z0-9])/g, ((_, char) => char.toUpperCase()));
}

function capitalize(value) {
  return value.charAt(0).toUpperCase() + value.slice(1);
}

function dasherize(value) {
  return value.replace(/([A-Z])/g, ((_, char) => `-${char.toLowerCase()}`));
}

class DataMap {
  constructor(scope) {
    this.scope = scope;
  }
  get element() {
    return this.scope.element;
  }
  get identifier() {
    return this.scope.identifier;
  }
  get(key) {
    const name = this.getAttributeNameForKey(key);
    return this.element.getAttribute(name);
  }
  set(key, value) {
    const name = this.getAttributeNameForKey(key);
    this.element.setAttribute(name, value);
    return this.get(key);
  }
  has(key) {
    const name = this.getAttributeNameForKey(key);
    return this.element.hasAttribute(name);
  }
  delete(key) {
    if (this.has(key)) {
      const name = this.getAttributeNameForKey(key);
      this.element.removeAttribute(name);
      return true;
    } else {
      return false;
    }
  }
  getAttributeNameForKey(key) {
    return `data-${this.identifier}-${dasherize(key)}`;
  }
}

class Guide {
  constructor(logger) {
    this.warnedKeysByObject = new WeakMap;
    this.logger = logger;
  }
  warn(object, key, message) {
    let warnedKeys = this.warnedKeysByObject.get(object);
    if (!warnedKeys) {
      warnedKeys = new Set;
      this.warnedKeysByObject.set(object, warnedKeys);
    }
    if (!warnedKeys.has(key)) {
      warnedKeys.add(key);
      this.logger.warn(message, object);
    }
  }
}

function attributeValueContainsToken(attributeName, token) {
  return `[${attributeName}~="${token}"]`;
}

class TargetSet {
  constructor(scope) {
    this.scope = scope;
  }
  get element() {
    return this.scope.element;
  }
  get identifier() {
    return this.scope.identifier;
  }
  get schema() {
    return this.scope.schema;
  }
  has(targetName) {
    return this.find(targetName) != null;
  }
  find(...targetNames) {
    return targetNames.reduce(((target, targetName) => target || this.findTarget(targetName) || this.findLegacyTarget(targetName)), undefined);
  }
  findAll(...targetNames) {
    return targetNames.reduce(((targets, targetName) => [ ...targets, ...this.findAllTargets(targetName), ...this.findAllLegacyTargets(targetName) ]), []);
  }
  findTarget(targetName) {
    const selector = this.getSelectorForTargetName(targetName);
    return this.scope.findElement(selector);
  }
  findAllTargets(targetName) {
    const selector = this.getSelectorForTargetName(targetName);
    return this.scope.findAllElements(selector);
  }
  getSelectorForTargetName(targetName) {
    const attributeName = `data-${this.identifier}-target`;
    return attributeValueContainsToken(attributeName, targetName);
  }
  findLegacyTarget(targetName) {
    const selector = this.getLegacySelectorForTargetName(targetName);
    return this.deprecate(this.scope.findElement(selector), targetName);
  }
  findAllLegacyTargets(targetName) {
    const selector = this.getLegacySelectorForTargetName(targetName);
    return this.scope.findAllElements(selector).map((element => this.deprecate(element, targetName)));
  }
  getLegacySelectorForTargetName(targetName) {
    const targetDescriptor = `${this.identifier}.${targetName}`;
    return attributeValueContainsToken(this.schema.targetAttribute, targetDescriptor);
  }
  deprecate(element, targetName) {
    if (element) {
      const {identifier: identifier} = this;
      const attributeName = this.schema.targetAttribute;
      this.guide.warn(element, `target:${targetName}`, `Please replace ${attributeName}="${identifier}.${targetName}" with data-${identifier}-target="${targetName}". ` + `The ${attributeName} attribute is deprecated and will be removed in a future version of Stimulus.`);
    }
    return element;
  }
  get guide() {
    return this.scope.guide;
  }
}

class Scope {
  constructor(schema, element, identifier, logger) {
    this.targets = new TargetSet(this);
    this.classes = new ClassMap(this);
    this.data = new DataMap(this);
    this.containsElement = element => element.closest(this.controllerSelector) === this.element;
    this.schema = schema;
    this.element = element;
    this.identifier = identifier;
    this.guide = new Guide(logger);
  }
  findElement(selector) {
    return this.element.matches(selector) ? this.element : this.queryElements(selector).find(this.containsElement);
  }
  findAllElements(selector) {
    return [ ...this.element.matches(selector) ? [ this.element ] : [], ...this.queryElements(selector).filter(this.containsElement) ];
  }
  queryElements(selector) {
    return Array.from(this.element.querySelectorAll(selector));
  }
  get controllerSelector() {
    return attributeValueContainsToken(this.schema.controllerAttribute, this.identifier);
  }
}

class ScopeObserver {
  constructor(element, schema, delegate) {
    this.element = element;
    this.schema = schema;
    this.delegate = delegate;
    this.valueListObserver = new ValueListObserver(this.element, this.controllerAttribute, this);
    this.scopesByIdentifierByElement = new WeakMap;
    this.scopeReferenceCounts = new WeakMap;
  }
  start() {
    this.valueListObserver.start();
  }
  stop() {
    this.valueListObserver.stop();
  }
  get controllerAttribute() {
    return this.schema.controllerAttribute;
  }
  parseValueForToken(token) {
    const {element: element, content: identifier} = token;
    const scopesByIdentifier = this.fetchScopesByIdentifierForElement(element);
    let scope = scopesByIdentifier.get(identifier);
    if (!scope) {
      scope = this.delegate.createScopeForElementAndIdentifier(element, identifier);
      scopesByIdentifier.set(identifier, scope);
    }
    return scope;
  }
  elementMatchedValue(element, value) {
    const referenceCount = (this.scopeReferenceCounts.get(value) || 0) + 1;
    this.scopeReferenceCounts.set(value, referenceCount);
    if (referenceCount == 1) {
      this.delegate.scopeConnected(value);
    }
  }
  elementUnmatchedValue(element, value) {
    const referenceCount = this.scopeReferenceCounts.get(value);
    if (referenceCount) {
      this.scopeReferenceCounts.set(value, referenceCount - 1);
      if (referenceCount == 1) {
        this.delegate.scopeDisconnected(value);
      }
    }
  }
  fetchScopesByIdentifierForElement(element) {
    let scopesByIdentifier = this.scopesByIdentifierByElement.get(element);
    if (!scopesByIdentifier) {
      scopesByIdentifier = new Map;
      this.scopesByIdentifierByElement.set(element, scopesByIdentifier);
    }
    return scopesByIdentifier;
  }
}

class Router {
  constructor(application) {
    this.application = application;
    this.scopeObserver = new ScopeObserver(this.element, this.schema, this);
    this.scopesByIdentifier = new Multimap;
    this.modulesByIdentifier = new Map;
  }
  get element() {
    return this.application.element;
  }
  get schema() {
    return this.application.schema;
  }
  get logger() {
    return this.application.logger;
  }
  get controllerAttribute() {
    return this.schema.controllerAttribute;
  }
  get modules() {
    return Array.from(this.modulesByIdentifier.values());
  }
  get contexts() {
    return this.modules.reduce(((contexts, module) => contexts.concat(module.contexts)), []);
  }
  start() {
    this.scopeObserver.start();
  }
  stop() {
    this.scopeObserver.stop();
  }
  loadDefinition(definition) {
    this.unloadIdentifier(definition.identifier);
    const module = new Module(this.application, definition);
    this.connectModule(module);
  }
  unloadIdentifier(identifier) {
    const module = this.modulesByIdentifier.get(identifier);
    if (module) {
      this.disconnectModule(module);
    }
  }
  getContextForElementAndIdentifier(element, identifier) {
    const module = this.modulesByIdentifier.get(identifier);
    if (module) {
      return module.contexts.find((context => context.element == element));
    }
  }
  handleError(error, message, detail) {
    this.application.handleError(error, message, detail);
  }
  createScopeForElementAndIdentifier(element, identifier) {
    return new Scope(this.schema, element, identifier, this.logger);
  }
  scopeConnected(scope) {
    this.scopesByIdentifier.add(scope.identifier, scope);
    const module = this.modulesByIdentifier.get(scope.identifier);
    if (module) {
      module.connectContextForScope(scope);
    }
  }
  scopeDisconnected(scope) {
    this.scopesByIdentifier.delete(scope.identifier, scope);
    const module = this.modulesByIdentifier.get(scope.identifier);
    if (module) {
      module.disconnectContextForScope(scope);
    }
  }
  connectModule(module) {
    this.modulesByIdentifier.set(module.identifier, module);
    const scopes = this.scopesByIdentifier.getValuesForKey(module.identifier);
    scopes.forEach((scope => module.connectContextForScope(scope)));
  }
  disconnectModule(module) {
    this.modulesByIdentifier.delete(module.identifier);
    const scopes = this.scopesByIdentifier.getValuesForKey(module.identifier);
    scopes.forEach((scope => module.disconnectContextForScope(scope)));
  }
}

const defaultSchema = {
  controllerAttribute: "data-controller",
  actionAttribute: "data-action",
  targetAttribute: "data-target",
  classAttribute: "data-class"
};

class Application {
  constructor(element = document.documentElement, schema = defaultSchema) {
    this.logger = console;
    this.element = element;
    this.schema = schema;
    this.dispatcher = new Dispatcher(this);
    this.router = new Router(this);
  }
  static start(element, schema) {
    const application = new Application(element, schema);
    application.start();
    return application;
  }
  async start() {
    await domReady();
    this.dispatcher.start();
    this.router.start();
  }
  stop() {
    this.dispatcher.stop();
    this.router.stop();
  }
  register(identifier, controllerConstructor) {
    this.load({
      identifier: identifier,
      controllerConstructor: controllerConstructor
    });
  }
  load(head, ...rest) {
    const definitions = Array.isArray(head) ? head : [ head, ...rest ];
    definitions.forEach((definition => this.router.loadDefinition(definition)));
  }
  unload(head, ...rest) {
    const identifiers = Array.isArray(head) ? head : [ head, ...rest ];
    identifiers.forEach((identifier => this.router.unloadIdentifier(identifier)));
  }
  get controllers() {
    return this.router.contexts.map((context => context.controller));
  }
  getControllerForElementAndIdentifier(element, identifier) {
    const context = this.router.getContextForElementAndIdentifier(element, identifier);
    return context ? context.controller : null;
  }
  handleError(error, message, detail) {
    this.logger.error(`%s\n\n%o\n\n%o`, message, error, detail);
  }
}

function domReady() {
  return new Promise((resolve => {
    if (document.readyState == "loading") {
      document.addEventListener("DOMContentLoaded", resolve);
    } else {
      resolve();
    }
  }));
}

function ClassPropertiesBlessing(constructor) {
  const classes = readInheritableStaticArrayValues(constructor, "classes");
  return classes.reduce(((properties, classDefinition) => Object.assign(properties, propertiesForClassDefinition(classDefinition))), {});
}

function propertiesForClassDefinition(key) {
  const name = `${key}Class`;
  return {
    [name]: {
      get() {
        const {classes: classes} = this;
        if (classes.has(key)) {
          return classes.get(key);
        } else {
          const attribute = classes.getAttributeName(key);
          throw new Error(`Missing attribute "${attribute}"`);
        }
      }
    },
    [`has${capitalize(name)}`]: {
      get() {
        return this.classes.has(key);
      }
    }
  };
}

function TargetPropertiesBlessing(constructor) {
  const targets = readInheritableStaticArrayValues(constructor, "targets");
  return targets.reduce(((properties, targetDefinition) => Object.assign(properties, propertiesForTargetDefinition(targetDefinition))), {});
}

function propertiesForTargetDefinition(name) {
  return {
    [`${name}Target`]: {
      get() {
        const target = this.targets.find(name);
        if (target) {
          return target;
        } else {
          throw new Error(`Missing target element "${this.identifier}.${name}"`);
        }
      }
    },
    [`${name}Targets`]: {
      get() {
        return this.targets.findAll(name);
      }
    },
    [`has${capitalize(name)}Target`]: {
      get() {
        return this.targets.has(name);
      }
    }
  };
}

function ValuePropertiesBlessing(constructor) {
  const valueDefinitionPairs = readInheritableStaticObjectPairs(constructor, "values");
  const propertyDescriptorMap = {
    valueDescriptorMap: {
      get() {
        return valueDefinitionPairs.reduce(((result, valueDefinitionPair) => {
          const valueDescriptor = parseValueDefinitionPair(valueDefinitionPair);
          const attributeName = this.data.getAttributeNameForKey(valueDescriptor.key);
          return Object.assign(result, {
            [attributeName]: valueDescriptor
          });
        }), {});
      }
    }
  };
  return valueDefinitionPairs.reduce(((properties, valueDefinitionPair) => Object.assign(properties, propertiesForValueDefinitionPair(valueDefinitionPair))), propertyDescriptorMap);
}

function propertiesForValueDefinitionPair(valueDefinitionPair) {
  const definition = parseValueDefinitionPair(valueDefinitionPair);
  const {type: type, key: key, name: name} = definition;
  const read = readers[type], write = writers[type] || writers.default;
  return {
    [name]: {
      get() {
        const value = this.data.get(key);
        if (value !== null) {
          return read(value);
        } else {
          return definition.defaultValue;
        }
      },
      set(value) {
        if (value === undefined) {
          this.data.delete(key);
        } else {
          this.data.set(key, write(value));
        }
      }
    },
    [`has${capitalize(name)}`]: {
      get() {
        return this.data.has(key);
      }
    }
  };
}

function parseValueDefinitionPair([token, typeConstant]) {
  const type = parseValueTypeConstant(typeConstant);
  return valueDescriptorForTokenAndType(token, type);
}

function parseValueTypeConstant(typeConstant) {
  switch (typeConstant) {
   case Array:
    return "array";

   case Boolean:
    return "boolean";

   case Number:
    return "number";

   case Object:
    return "object";

   case String:
    return "string";
  }
  throw new Error(`Unknown value type constant "${typeConstant}"`);
}

function valueDescriptorForTokenAndType(token, type) {
  const key = `${dasherize(token)}-value`;
  return {
    type: type,
    key: key,
    name: camelize(key),
    get defaultValue() {
      return defaultValuesByType[type];
    }
  };
}

const defaultValuesByType = {
  get array() {
    return [];
  },
  boolean: false,
  number: 0,
  get object() {
    return {};
  },
  string: ""
};

const readers = {
  array(value) {
    const array = JSON.parse(value);
    if (!Array.isArray(array)) {
      throw new TypeError("Expected array");
    }
    return array;
  },
  boolean(value) {
    return !(value == "0" || value == "false");
  },
  number(value) {
    return parseFloat(value);
  },
  object(value) {
    const object = JSON.parse(value);
    if (object === null || typeof object != "object" || Array.isArray(object)) {
      throw new TypeError("Expected object");
    }
    return object;
  },
  string(value) {
    return value;
  }
};

const writers = {
  default: writeString,
  array: writeJSON,
  object: writeJSON
};

function writeJSON(value) {
  return JSON.stringify(value);
}

function writeString(value) {
  return `${value}`;
}

class Controller {
  constructor(context) {
    this.context = context;
  }
  get application() {
    return this.context.application;
  }
  get scope() {
    return this.context.scope;
  }
  get element() {
    return this.scope.element;
  }
  get identifier() {
    return this.scope.identifier;
  }
  get targets() {
    return this.scope.targets;
  }
  get classes() {
    return this.scope.classes;
  }
  get data() {
    return this.scope.data;
  }
  initialize() {}
  connect() {}
  disconnect() {}
}

Controller.blessings = [ ClassPropertiesBlessing, TargetPropertiesBlessing, ValuePropertiesBlessing ];

Controller.targets = [];

Controller.values = {};

export { Application, Context, Controller, defaultSchema };