states.js

//
// This file is automatically generated. any changes will be lost
//

require("./runtime");


(function() {
var get = Ember.get, set = Ember.set;

/**
@module ember
@submodule ember-states
*/

/**
  @class State
  @namespace Ember
  @extends Ember.Object
  @uses Ember.Evented
*/
Ember.State = Ember.Object.extend(Ember.Evented,
/** @scope Ember.State.prototype */{
  isState: true,

  /**
    A reference to the parent state.

    @property parentState
    @type Ember.State
  */
  parentState: null,
  start: null,

  /**
    The name of this state.

    @property name
    @type String
  */
  name: null,

  /**
    The full path to this state.

    @property path
    @type String
  */
  path: Ember.computed(function() {
    var parentPath = get(this, 'parentState.path'),
        path = get(this, 'name');

    if (parentPath) {
      path = parentPath + '.' + path;
    }

    return path;
  }).property(),

  /**
    @private

    Override the default event firing from Ember.Evented to
    also call methods with the given name.

    @method trigger
    @param name
  */
  trigger: function(name) {
    if (this[name]) {
      this[name].apply(this, [].slice.call(arguments, 1));
    }
    this._super.apply(this, arguments);
  },

  init: function() {
    var states = get(this, 'states'), foundStates;
    set(this, 'childStates', Ember.A());
    set(this, 'eventTransitions', get(this, 'eventTransitions') || {});

    var name, value, transitionTarget;

    // As a convenience, loop over the properties
    // of this state and look for any that are other
    // Ember.State instances or classes, and move them
    // to the `states` hash. This avoids having to
    // create an explicit separate hash.

    if (!states) {
      states = {};

      for (name in this) {
        if (name === "constructor") { continue; }

        if (value = this[name]) {
          if (transitionTarget = value.transitionTarget) {
            this.eventTransitions[name] = transitionTarget;
          }

          this.setupChild(states, name, value);
        }
      }

      set(this, 'states', states);
    } else {
      for (name in states) {
        this.setupChild(states, name, states[name]);
      }
    }

    set(this, 'pathsCache', {});
    set(this, 'pathsCacheNoContext', {});
  },

  setupChild: function(states, name, value) {
    if (!value) { return false; }

    if (value.isState) {
      set(value, 'name', name);
    } else if (Ember.State.detect(value)) {
      value = value.create({
        name: name
      });
    }

    if (value.isState) {
      set(value, 'parentState', this);
      get(this, 'childStates').pushObject(value);
      states[name] = value;
      return value;
    }
  },

  lookupEventTransition: function(name) {
    var path, state = this;

    while(state && !path) {
      path = state.eventTransitions[name];
      state = state.get('parentState');
    }

    return path;
  },

  /**
    A Boolean value indicating whether the state is a leaf state
    in the state hierarchy. This is false if the state has child
    states; otherwise it is true.

    @property isLeaf
    @type Boolean
  */
  isLeaf: Ember.computed(function() {
    return !get(this, 'childStates').length;
  }),

  /**
    A boolean value indicating whether the state takes a context.
    By default we assume all states take contexts.

    @property hasContext
    @default true
  */
  hasContext: true,

  /**
    This is the default transition event.

    @event setup
    @param {Ember.StateManager} manager
    @param context
    @see Ember.StateManager#transitionEvent
  */
  setup: Ember.K,

  /**
    This event fires when the state is entered.

    @event enter
    @param {Ember.StateManager} manager
  */
  enter: Ember.K,

  /**
    This event fires when the state is exited.

    @event exit
    @param {Ember.StateManager} manager
  */
  exit: Ember.K
});

Ember.State.reopenClass({

  /**
    Creates an action function for transitioning to the named state while preserving context.

    The following example StateManagers are equivalent:

        aManager = Ember.StateManager.create({
          stateOne: Ember.State.create({
            changeToStateTwo: Ember.State.transitionTo('stateTwo')
          }),
          stateTwo: Ember.State.create({})
        })

        bManager = Ember.StateManager.create({
          stateOne: Ember.State.create({
            changeToStateTwo: function(manager, context){
              manager.transitionTo('stateTwo', context)
            }
          }),
          stateTwo: Ember.State.create({})
        })

    @method transitionTo
    @static
    @param {String} target
  */

  transitionTo: function(target) {

    var transitionFunction = function(stateManager, contextOrEvent) {
      var contexts = [], transitionArgs,
          Event = Ember.$ && Ember.$.Event;

      if (contextOrEvent && (Event && contextOrEvent instanceof Event)) {
        if (contextOrEvent.hasOwnProperty('contexts')) {
          contexts = contextOrEvent.contexts.slice();
        }
      }
      else {
        contexts = [].slice.call(arguments, 1);
      }

      contexts.unshift(target);
      stateManager.transitionTo.apply(stateManager, contexts);
    };

    transitionFunction.transitionTarget = target;

    return transitionFunction;
  }

});

})();



(function() {
/**
@module ember
@submodule ember-states
*/

var get = Ember.get, set = Ember.set, fmt = Ember.String.fmt;
var arrayForEach = Ember.ArrayPolyfills.forEach;
/**
  A Transition takes the enter, exit and resolve states and normalizes
  them:

  * takes any passed in contexts into consideration
  * adds in `initialState`s

  @class Transition
  @private
*/
var Transition = function(raw) {
  this.enterStates = raw.enterStates.slice();
  this.exitStates = raw.exitStates.slice();
  this.resolveState = raw.resolveState;

  this.finalState = raw.enterStates[raw.enterStates.length - 1] || raw.resolveState;
};

Transition.prototype = {
  /**
    Normalize the passed in enter, exit and resolve states.

    This process also adds `finalState` and `contexts` to the Transition object.

    @method normalize
    @param {Ember.StateManager} manager the state manager running the transition
    @param {Array} contexts a list of contexts passed into `transitionTo`
  */
  normalize: function(manager, contexts) {
    this.matchContextsToStates(contexts);
    this.addInitialStates();
    this.removeUnchangedContexts(manager);
    return this;
  },

  /**
    Match each of the contexts passed to `transitionTo` to a state.
    This process may also require adding additional enter and exit
    states if there are more contexts than enter states.

    @method matchContextsToStates
    @param {Array} contexts a list of contexts passed into `transitionTo`
  */
  matchContextsToStates: function(contexts) {
    var stateIdx = this.enterStates.length - 1,
        matchedContexts = [],
        state,
        context;

    // Next, we will match the passed in contexts to the states they
    // represent.
    //
    // First, assign a context to each enter state in reverse order. If
    // any contexts are left, add a parent state to the list of states
    // to enter and exit, and assign a context to the parent state.
    //
    // If there are still contexts left when the state manager is
    // reached, raise an exception.
    //
    // This allows the following:
    //
    // |- root
    // | |- post
    // | | |- comments
    // | |- about (* current state)
    //
    // For `transitionTo('post.comments', post, post.get('comments')`,
    // the first context (`post`) will be assigned to `root.post`, and
    // the second context (`post.get('comments')`) will be assigned
    // to `root.post.comments`.
    //
    // For the following:
    //
    // |- root
    // | |- post
    // | | |- index (* current state)
    // | | |- comments
    //
    // For `transitionTo('post.comments', otherPost, otherPost.get('comments')`,
    // the `<root.post>` state will be added to the list of enter and exit
    // states because its context has changed.

    while (contexts.length > 0) {
      if (stateIdx >= 0) {
        state = this.enterStates[stateIdx--];
      } else {
        if (this.enterStates.length) {
          state = get(this.enterStates[0], 'parentState');
          if (!state) { throw "Cannot match all contexts to states"; }
        } else {
          // If re-entering the current state with a context, the resolve
          // state will be the current state.
          state = this.resolveState;
        }

        this.enterStates.unshift(state);
        this.exitStates.unshift(state);
      }

      // in routers, only states with dynamic segments have a context
      if (get(state, 'hasContext')) {
        context = contexts.pop();
      } else {
        context = null;
      }

      matchedContexts.unshift(context);
    }

    this.contexts = matchedContexts;
  },

  /**
    Add any `initialState`s to the list of enter states.

    @method addInitialStates
  */
  addInitialStates: function() {
    var finalState = this.finalState, initialState;

    while(true) {
      initialState = get(finalState, 'initialState') || 'start';
      finalState = get(finalState, 'states.' + initialState);

      if (!finalState) { break; }

      this.finalState = finalState;
      this.enterStates.push(finalState);
      this.contexts.push(undefined);
    }
  },

  /**
    Remove any states that were added because the number of contexts
    exceeded the number of explicit enter states, but the context has
    not changed since the last time the state was entered.

    @method removeUnchangedContexts
    @param {Ember.StateManager} manager passed in to look up the last
      context for a states
  */
  removeUnchangedContexts: function(manager) {
    // Start from the beginning of the enter states. If the state was added
    // to the list during the context matching phase, make sure the context
    // has actually changed since the last time the state was entered.
    while (this.enterStates.length > 0) {
      if (this.enterStates[0] !== this.exitStates[0]) { break; }

      if (this.enterStates.length === this.contexts.length) {
        if (manager.getStateMeta(this.enterStates[0], 'context') !== this.contexts[0]) { break; }
        this.contexts.shift();
      }

      this.resolveState = this.enterStates.shift();
      this.exitStates.shift();
    }
  }
};

/**
  StateManager is part of Ember's implementation of a finite state machine. A StateManager
  instance manages a number of properties that are instances of `Ember.State`,
  tracks the current active state, and triggers callbacks when states have changed.

  ## Defining States

  The states of StateManager can be declared in one of two ways. First, you can define
  a `states` property that contains all the states:

      managerA = Ember.StateManager.create({
        states: {
          stateOne: Ember.State.create(),
          stateTwo: Ember.State.create()
        }
      })

      managerA.get('states')
      // {
      //   stateOne: Ember.State.create(),
      //   stateTwo: Ember.State.create()
      // }

  You can also add instances of `Ember.State` (or an `Ember.State` subclass) directly as properties
  of a StateManager. These states will be collected into the `states` property for you.

      managerA = Ember.StateManager.create({
        stateOne: Ember.State.create(),
        stateTwo: Ember.State.create()
      })

      managerA.get('states')
      // {
      //   stateOne: Ember.State.create(),
      //   stateTwo: Ember.State.create()
      // }

  ## The Initial State
  When created a StateManager instance will immediately enter into the state
  defined as its `start` property or the state referenced by name in its
  `initialState` property:

      managerA = Ember.StateManager.create({
        start: Ember.State.create({})
      })

      managerA.get('currentState.name') // 'start'

      managerB = Ember.StateManager.create({
        initialState: 'beginHere',
        beginHere: Ember.State.create({})
      })

      managerB.get('currentState.name') // 'beginHere'

  Because it is a property you may also provide a computed function if you wish to derive
  an `initialState` programmatically:

      managerC = Ember.StateManager.create({
        initialState: function(){
          if (someLogic) {
            return 'active';
          } else {
            return 'passive';
          }
        }.property(),
        active: Ember.State.create({}),
        passive: Ember.State.create({})
      })

  ## Moving Between States
  A StateManager can have any number of Ember.State objects as properties
  and can have a single one of these states as its current state.

  Calling `transitionTo` transitions between states:

      robotManager = Ember.StateManager.create({
        initialState: 'poweredDown',
        poweredDown: Ember.State.create({}),
        poweredUp: Ember.State.create({})
      })

      robotManager.get('currentState.name') // 'poweredDown'
      robotManager.transitionTo('poweredUp')
      robotManager.get('currentState.name') // 'poweredUp'

  Before transitioning into a new state the existing `currentState` will have its
  `exit` method called with the StateManager instance as its first argument and
  an object representing the transition as its second argument.

  After transitioning into a new state the new `currentState` will have its
  `enter` method called with the StateManager instance as its first argument and
  an object representing the transition as its second argument.

      robotManager = Ember.StateManager.create({
        initialState: 'poweredDown',
        poweredDown: Ember.State.create({
          exit: function(stateManager){
            console.log("exiting the poweredDown state")
          }
        }),
        poweredUp: Ember.State.create({
          enter: function(stateManager){
            console.log("entering the poweredUp state. Destroy all humans.")
          }
        })
      })

      robotManager.get('currentState.name') // 'poweredDown'
      robotManager.transitionTo('poweredUp')
      // will log
      // 'exiting the poweredDown state'
      // 'entering the poweredUp state. Destroy all humans.'


  Once a StateManager is already in a state, subsequent attempts to enter that state will
  not trigger enter or exit method calls. Attempts to transition into a state that the
  manager does not have will result in no changes in the StateManager's current state:

      robotManager = Ember.StateManager.create({
        initialState: 'poweredDown',
        poweredDown: Ember.State.create({
          exit: function(stateManager){
            console.log("exiting the poweredDown state")
          }
        }),
        poweredUp: Ember.State.create({
          enter: function(stateManager){
            console.log("entering the poweredUp state. Destroy all humans.")
          }
        })
      })

      robotManager.get('currentState.name') // 'poweredDown'
      robotManager.transitionTo('poweredUp')
      // will log
      // 'exiting the poweredDown state'
      // 'entering the poweredUp state. Destroy all humans.'
      robotManager.transitionTo('poweredUp') // no logging, no state change

      robotManager.transitionTo('someUnknownState') // silently fails
      robotManager.get('currentState.name') // 'poweredUp'


  Each state property may itself contain properties that are instances of Ember.State.
  The StateManager can transition to specific sub-states in a series of transitionTo method calls or
  via a single transitionTo with the full path to the specific state. The StateManager will also
  keep track of the full path to its currentState

      robotManager = Ember.StateManager.create({
        initialState: 'poweredDown',
        poweredDown: Ember.State.create({
          charging: Ember.State.create(),
          charged: Ember.State.create()
        }),
        poweredUp: Ember.State.create({
          mobile: Ember.State.create(),
          stationary: Ember.State.create()
        })
      })

      robotManager.get('currentState.name') // 'poweredDown'

      robotManager.transitionTo('poweredUp')
      robotManager.get('currentState.name') // 'poweredUp'

      robotManager.transitionTo('mobile')
      robotManager.get('currentState.name') // 'mobile'

      // transition via a state path
      robotManager.transitionTo('poweredDown.charging')
      robotManager.get('currentState.name') // 'charging'

      robotManager.get('currentState.path') // 'poweredDown.charging'

  Enter transition methods will be called for each state and nested child state in their
  hierarchical order.  Exit methods will be called for each state and its nested states in
  reverse hierarchical order.

  Exit transitions for a parent state are not called when entering into one of its child states,
  only when transitioning to a new section of possible states in the hierarchy.

      robotManager = Ember.StateManager.create({
        initialState: 'poweredDown',
        poweredDown: Ember.State.create({
          enter: function(){},
          exit: function(){
            console.log("exited poweredDown state")
          },
          charging: Ember.State.create({
            enter: function(){},
            exit: function(){}
          }),
          charged: Ember.State.create({
            enter: function(){
              console.log("entered charged state")
            },
            exit: function(){
              console.log("exited charged state")
            }
          })
        }),
        poweredUp: Ember.State.create({
          enter: function(){
            console.log("entered poweredUp state")
          },
          exit: function(){},
          mobile: Ember.State.create({
            enter: function(){
              console.log("entered mobile state")
            },
            exit: function(){}
          }),
          stationary: Ember.State.create({
            enter: function(){},
            exit: function(){}
          })
        })
      })


      robotManager.get('currentState.path') // 'poweredDown'
      robotManager.transitionTo('charged')
      // logs 'entered charged state'
      // but does *not* log  'exited poweredDown state'
      robotManager.get('currentState.name') // 'charged

      robotManager.transitionTo('poweredUp.mobile')
      // logs
      // 'exited charged state'
      // 'exited poweredDown state'
      // 'entered poweredUp state'
      // 'entered mobile state'

  During development you can set a StateManager's `enableLogging` property to `true` to
  receive console messages of state transitions.

      robotManager = Ember.StateManager.create({
        enableLogging: true
      })

  ## Managing currentState with Actions
  To control which transitions between states are possible for a given state, StateManager
  can receive and route action messages to its states via the `send` method.  Calling to `send` with
  an action name will begin searching for a method with the same name starting at the current state
  and moving up through the parent states in a state hierarchy until an appropriate method is found
  or the StateManager instance itself is reached.

  If an appropriately named method is found it will be called with the state manager as the first
  argument and an optional `context` object as the second argument.

      managerA = Ember.StateManager.create({
        initialState: 'stateOne.substateOne.subsubstateOne',
        stateOne: Ember.State.create({
          substateOne: Ember.State.create({
            anAction: function(manager, context){
              console.log("an action was called")
            },
            subsubstateOne: Ember.State.create({})
          })
        })
      })

      managerA.get('currentState.name') // 'subsubstateOne'
      managerA.send('anAction')
      // 'stateOne.substateOne.subsubstateOne' has no anAction method
      // so the 'anAction' method of 'stateOne.substateOne' is called
      // and logs "an action was called"
      // with managerA as the first argument
      // and no second argument

      someObject = {}
      managerA.send('anAction', someObject)
      // the 'anAction' method of 'stateOne.substateOne' is called again
      // with managerA as the first argument and
      // someObject as the second argument.


  If the StateManager attempts to send an action but does not find an appropriately named
  method in the current state or while moving upwards through the state hierarchy
  it will throw a new Ember.Error. Action detection only moves upwards through the state hierarchy
  from the current state. It does not search in other portions of the hierarchy.

      managerB = Ember.StateManager.create({
        initialState: 'stateOne.substateOne.subsubstateOne',
        stateOne: Ember.State.create({
          substateOne: Ember.State.create({
            subsubstateOne: Ember.State.create({})
          })
        }),
        stateTwo: Ember.State.create({
         anAction: function(manager, context){
           // will not be called below because it is
           // not a parent of the current state
         }
        })
      })

      managerB.get('currentState.name') // 'subsubstateOne'
      managerB.send('anAction')
      // Error: <Ember.StateManager:ember132> could not
      // respond to event anAction in state stateOne.substateOne.subsubstateOne.

  Inside of an action method the given state should delegate `transitionTo` calls on its
  StateManager.

      robotManager = Ember.StateManager.create({
        initialState: 'poweredDown.charging',
        poweredDown: Ember.State.create({
          charging: Ember.State.create({
            chargeComplete: function(manager, context){
              manager.transitionTo('charged')
            }
          }),
          charged: Ember.State.create({
            boot: function(manager, context){
              manager.transitionTo('poweredUp')
            }
          })
        }),
        poweredUp: Ember.State.create({
          beginExtermination: function(manager, context){
            manager.transitionTo('rampaging')
          },
          rampaging: Ember.State.create()
        })
      })

      robotManager.get('currentState.name') // 'charging'
      robotManager.send('boot') // throws error, no boot action
                                // in current hierarchy
      robotManager.get('currentState.name') // remains 'charging'

      robotManager.send('beginExtermination') // throws error, no beginExtermination
                                              // action in current hierarchy
      robotManager.get('currentState.name') // remains 'charging'

      robotManager.send('chargeComplete')
      robotManager.get('currentState.name') // 'charged'

      robotManager.send('boot')
      robotManager.get('currentState.name') // 'poweredUp'

      robotManager.send('beginExtermination', allHumans)
      robotManager.get('currentState.name') // 'rampaging'

  Transition actions can also be created using the `transitionTo` method of the Ember.State class. The
  following example StateManagers are equivalent:

      aManager = Ember.StateManager.create({
        stateOne: Ember.State.create({
          changeToStateTwo: Ember.State.transitionTo('stateTwo')
        }),
        stateTwo: Ember.State.create({})
      })

      bManager = Ember.StateManager.create({
        stateOne: Ember.State.create({
          changeToStateTwo: function(manager, context){
            manager.transitionTo('stateTwo', context)
          }
        }),
        stateTwo: Ember.State.create({})
      })

  @class StateManager
  @namespace Ember
  @extends Ember.State
**/
Ember.StateManager = Ember.State.extend({
  /**
    @private

    When creating a new statemanager, look for a default state to transition
    into. This state can either be named `start`, or can be specified using the
    `initialState` property.

    @method init
  */
  init: function() {
    this._super();

    set(this, 'stateMeta', Ember.Map.create());

    var initialState = get(this, 'initialState');

    if (!initialState && get(this, 'states.start')) {
      initialState = 'start';
    }

    if (initialState) {
      this.transitionTo(initialState);
      Ember.assert('Failed to transition to initial state "' + initialState + '"', !!get(this, 'currentState'));
    }
  },

  stateMetaFor: function(state) {
    var meta = get(this, 'stateMeta'),
        stateMeta = meta.get(state);

    if (!stateMeta) {
      stateMeta = {};
      meta.set(state, stateMeta);
    }

    return stateMeta;
  },

  setStateMeta: function(state, key, value) {
    return set(this.stateMetaFor(state), key, value);
  },

  getStateMeta: function(state, key) {
    return get(this.stateMetaFor(state), key);
  },

  /**
    The current state from among the manager's possible states. This property should
    not be set directly.  Use `transitionTo` to move between states by name.

    @property currentState
    @type Ember.State
  */
  currentState: null,

  /**
   The path of the current state. Returns a string representation of the current
   state.

   @property currentPath
   @type String
  */
  currentPath: Ember.computed('currentState', function() {
    return get(this, 'currentState.path');
  }),

  /**
    The name of transitionEvent that this stateManager will dispatch

    @property transitionEvent
    @type String
    @default 'setup'
  */
  transitionEvent: 'setup',

  /**
    If set to true, `errorOnUnhandledEvents` will cause an exception to be
    raised if you attempt to send an event to a state manager that is not
    handled by the current state or any of its parent states.

    @property errorOnUnhandledEvents
    @type Boolean
    @default true
  */
  errorOnUnhandledEvent: true,

  send: function(event) {
    var contexts, sendRecursiveArguments;

    Ember.assert('Cannot send event "' + event + '" while currentState is ' + get(this, 'currentState'), get(this, 'currentState'));

    contexts = [].slice.call(arguments, 1);
    sendRecursiveArguments = contexts;
    sendRecursiveArguments.unshift(event, get(this, 'currentState'));

    return this.sendRecursively.apply(this, sendRecursiveArguments);
  },

  sendRecursively: function(event, currentState) {
    var log = this.enableLogging,
        action = currentState[event],
        contexts, sendRecursiveArguments, actionArguments;

    contexts = [].slice.call(arguments, 2);

    // Test to see if the action is a method that
    // can be invoked. Don't blindly check just for
    // existence, because it is possible the state
    // manager has a child state of the given name,
    // and we should still raise an exception in that
    // case.
    if (typeof action === 'function') {
      if (log) { Ember.Logger.log(fmt("STATEMANAGER: Sending event '%@' to state %@.", [event, get(currentState, 'path')])); }

      actionArguments = contexts;
      actionArguments.unshift(this);

      return action.apply(currentState, actionArguments);
    } else {
      var parentState = get(currentState, 'parentState');
      if (parentState) {

        sendRecursiveArguments = contexts;
        sendRecursiveArguments.unshift(event, parentState);

        return this.sendRecursively.apply(this, sendRecursiveArguments);
      } else if (get(this, 'errorOnUnhandledEvent')) {
        throw new Ember.Error(this.toString() + " could not respond to event " + event + " in state " + get(this, 'currentState.path') + ".");
      }
    }
  },

  /**
    Finds a state by its state path.

    Example:

        manager = Ember.StateManager.create({
          root: Ember.State.create({
            dashboard: Ember.State.create()
          })
        });

        manager.getStateByPath(manager, "root.dashboard")

        // returns the dashboard state

    @method getStateByPath
    @param {Ember.State} root the state to start searching from
    @param {String} path the state path to follow
    @return {Ember.State} the state at the end of the path
  */
  getStateByPath: function(root, path) {
    var parts = path.split('.'),
        state = root;

    for (var i=0, len=parts.length; i<len; i++) {
      state = get(get(state, 'states'), parts[i]);
      if (!state) { break; }
    }

    return state;
  },

  findStateByPath: function(state, path) {
    var possible;

    while (!possible && state) {
      possible = this.getStateByPath(state, path);
      state = get(state, 'parentState');
    }

    return possible;
  },

  /**
    A state stores its child states in its `states` hash.
    This code takes a path like `posts.show` and looks
    up `root.states.posts.states.show`.

    It returns a list of all of the states from the
    root, which is the list of states to call `enter`
    on.

    @method getStatesInPath
    @param root
    @param path
  */
  getStatesInPath: function(root, path) {
    if (!path || path === "") { return undefined; }
    var parts = path.split('.'),
        result = [],
        states,
        state;

    for (var i=0, len=parts.length; i<len; i++) {
      states = get(root, 'states');
      if (!states) { return undefined; }
      state = get(states, parts[i]);
      if (state) { root = state; result.push(state); }
      else { return undefined; }
    }

    return result;
  },

  goToState: function() {
    // not deprecating this yet so people don't constantly need to
    // make trivial changes for little reason.
    return this.transitionTo.apply(this, arguments);
  },

  transitionTo: function(path, context) {
    // XXX When is transitionTo called with no path
    if (Ember.empty(path)) { return; }

    // The ES6 signature of this function is `path, ...contexts`
    var contexts = context ? Array.prototype.slice.call(arguments, 1) : [],
        currentState = get(this, 'currentState') || this;

    // First, get the enter, exit and resolve states for the current state
    // and specified path. If possible, use an existing cache.
    var hash = this.contextFreeTransition(currentState, path);

    // Next, process the raw state information for the contexts passed in.
    var transition = new Transition(hash).normalize(this, contexts);

    this.enterState(transition);
    this.triggerSetupContext(transition);
  },

  contextFreeTransition: function(currentState, path) {
    var cache = currentState.pathsCache[path];
    if (cache) { return cache; }

    var enterStates = this.getStatesInPath(currentState, path),
        exitStates = [],
        resolveState = currentState;

    // Walk up the states. For each state, check whether a state matching
    // the `path` is nested underneath. This will find the closest
    // parent state containing `path`.
    //
    // This allows the user to pass in a relative path. For example, for
    // the following state hierarchy:
    //
    //    | |root
    //    | |- posts
    //    | | |- show (* current)
    //    | |- comments
    //    | | |- show
    //
    // If the current state is `<root.posts.show>`, an attempt to
    // transition to `comments.show` will match `<root.comments.show>`.
    //
    // First, this code will look for root.posts.show.comments.show.
    // Next, it will look for root.posts.comments.show. Finally,
    // it will look for `root.comments.show`, and find the state.
    //
    // After this process, the following variables will exist:
    //
    // * resolveState: a common parent state between the current
    //   and target state. In the above example, `<root>` is the
    //   `resolveState`.
    // * enterStates: a list of all of the states represented
    //   by the path from the `resolveState`. For example, for
    //   the path `root.comments.show`, `enterStates` would have
    //   `[<root.comments>, <root.comments.show>]`
    // * exitStates: a list of all of the states from the
    //   `resolveState` to the `currentState`. In the above
    //   example, `exitStates` would have
    //   `[<root.posts>`, `<root.posts.show>]`.
    while (resolveState && !enterStates) {
      exitStates.unshift(resolveState);

      resolveState = get(resolveState, 'parentState');
      if (!resolveState) {
        enterStates = this.getStatesInPath(this, path);
        if (!enterStates) {
          Ember.assert('Could not find state for path: "'+path+'"');
          return;
        }
      }
      enterStates = this.getStatesInPath(resolveState, path);
    }

    // If the path contains some states that are parents of both the
    // current state and the target state, remove them.
    //
    // For example, in the following hierarchy:
    //
    // |- root
    // | |- post
    // | | |- index (* current)
    // | | |- show
    //
    // If the `path` is `root.post.show`, the three variables will
    // be:
    //
    // * resolveState: `<state manager>`
    // * enterStates: `[<root>, <root.post>, <root.post.show>]`
    // * exitStates: `[<root>, <root.post>, <root.post.index>]`
    //
    // The goal of this code is to remove the common states, so we
    // have:
    //
    // * resolveState: `<root.post>`
    // * enterStates: `[<root.post.show>]`
    // * exitStates: `[<root.post.index>]`
    //
    // This avoid unnecessary calls to the enter and exit transitions.
    while (enterStates.length > 0 && enterStates[0] === exitStates[0]) {
      resolveState = enterStates.shift();
      exitStates.shift();
    }

    // Cache the enterStates, exitStates, and resolveState for the
    // current state and the `path`.
    var transitions = currentState.pathsCache[path] = {
      exitStates: exitStates,
      enterStates: enterStates,
      resolveState: resolveState
    };

    return transitions;
  },

  triggerSetupContext: function(transitions) {
    var contexts = transitions.contexts,
        offset = transitions.enterStates.length - contexts.length,
        enterStates = transitions.enterStates,
        transitionEvent = get(this, 'transitionEvent');

    Ember.assert("More contexts provided than states", offset >= 0);

    arrayForEach.call(enterStates, function(state, idx) {
      state.trigger(transitionEvent, this, contexts[idx-offset]);
    }, this);
  },

  getState: function(name) {
    var state = get(this, name),
        parentState = get(this, 'parentState');

    if (state) {
      return state;
    } else if (parentState) {
      return parentState.getState(name);
    }
  },

  enterState: function(transition) {
    var log = this.enableLogging;

    var exitStates = transition.exitStates.slice(0).reverse();
    arrayForEach.call(exitStates, function(state) {
      state.trigger('exit', this);
    }, this);

    arrayForEach.call(transition.enterStates, function(state) {
      if (log) { Ember.Logger.log("STATEMANAGER: Entering " + get(state, 'path')); }
      state.trigger('enter', this);
    }, this);

    set(this, 'currentState', transition.finalState);
  }
});

})();



(function() {
/**
Ember States

@module ember
@submodule ember-states
@requires ember-runtime
*/

})();