5 files changed, 60 insertions, 16 deletions

diff --git a/packages/gitbook-core/src/actions/TYPES.js b/packages/gitbook-core/src/actions/TYPES.js
index e758a44..43eaac0 100644
--- a/packages/gitbook-core/src/actions/TYPES.js
+++ b/packages/gitbook-core/src/actions/TYPES.js
@@ -4,6 +4,7 @@ module.exports = {
     REGISTER_COMPONENT:   'components/register',
     UNREGISTER_COMPONENT: 'components/unregister',
     // Navigation
+    NAVIGATION_LISTEN:    'navigation/listen',
     PAGE_FETCH_START:     'navigation/fetch:start',
     PAGE_FETCH_END:       'navigation/fetch:end',
     PAGE_FETCH_ERROR:     'navigation/fetch:error',
diff --git a/packages/gitbook-core/src/actions/navigation.js b/packages/gitbook-core/src/actions/navigation.js
index 4afd4fb..fa82bcb 100644
--- a/packages/gitbook-core/src/actions/navigation.js
+++ b/packages/gitbook-core/src/actions/navigation.js
@@ -17,6 +17,32 @@ const SUPPORTED = (
 const history = isServerSide ? createMemoryHistory() : createBrowserHistory();
 
 /**
+ * Initialize the navigation
+ */
+function activate() {
+    return (dispatch, getState) => {
+        const { listeners } = getState().navigation;
+
+        history.listen(location => {
+            location = Location.fromNative(location);
+
+            listeners.forEach(listener => {
+                listener(location, dispatch, getState);
+            });
+        });
+    };
+}
+
+/**
+ * Cleanup the navigation
+ */
+function deactivate() {
+    return (dispatch, getState) => {
+
+    };
+}
+
+/**
  * Push a new url into the navigation
  * @param {String|Location} location
  * @return {Action} action
@@ -63,16 +89,11 @@ function redirect(uri) {
 
 /**
  * Listen to url change
- * @param {Function} fn
+ * @param {Function} listener
  * @return {Action} action
  */
-function listen(fn) {
-    return (dispatch, getState) => {
-        history.listen(location => {
-            location = Location.fromNative(location);
-            fn(location, dispatch, getState);
-        });
-    };
+function listen(listener) {
+    return { type: ACTION_TYPES.NAVIGATION_LISTEN, listener };
 }
 
 /**
@@ -152,6 +173,8 @@ function updateQuery(query) {
 }
 
 module.exports = {
+    activate,
+    deactivate,
     listen,
     pushURI,
     fetchPage,
diff --git a/packages/gitbook-core/src/lib/createContext.js b/packages/gitbook-core/src/lib/createContext.js
index ec240be..2a826d1 100644
--- a/packages/gitbook-core/src/lib/createContext.js
+++ b/packages/gitbook-core/src/lib/createContext.js
@@ -13,7 +13,18 @@ const Navigation = require('../actions/navigation');
 
 const isBrowser = (typeof window !== 'undefined');
 
+/**
+ * The core plugin defines the defualt behaviour of GitBook and provides
+ * actions to other plugins.
+ * @type {Plugin}
+ */
 const corePlugin = new Plugin({
+    activate: (dispatch) => {
+        dispatch(Navigation.activate());
+    },
+    deactivate: (dispatch) => {
+        dispatch(Navigation.deactivate());
+    },
     reduce: coreReducers,
     actions: {
         Components, I18n, Navigation
diff --git a/packages/gitbook-core/src/models/Plugin.js b/packages/gitbook-core/src/models/Plugin.js
index 7ca5a86..07b1976 100644
--- a/packages/gitbook-core/src/models/Plugin.js
+++ b/packages/gitbook-core/src/models/Plugin.js
@@ -1,17 +1,19 @@
 const { Record } = require('immutable');
 
 const DEFAULTS = {
-    init:   ((dispatch, getState) => {}),
-    reduce: ((state, action) => state),
-    actions: {}
+    activate:   ((dispatch, getState) => {}),
+    deactivate: ((dispatch, getState) => {}),
+    reduce:     ((state, action) => state),
+    actions:    {}
 };
 
 class Plugin extends Record(DEFAULTS) {
     constructor(plugin) {
         super({
-            init: plugin.init || DEFAULTS.init,
-            reduce: plugin.reduce || DEFAULTS.reduce,
-            actions: plugin.actions || DEFAULTS.actions
+            activate:   plugin.activate || DEFAULTS.activate,
+            deactivate: plugin.deactivate || DEFAULTS.deactivate,
+            reduce:     plugin.reduce || DEFAULTS.reduce,
+            actions:    plugin.actions || DEFAULTS.actions
         });
     }
 }
diff --git a/packages/gitbook-core/src/reducers/navigation.js b/packages/gitbook-core/src/reducers/navigation.js
index 9831cd5..439ba21 100644
--- a/packages/gitbook-core/src/reducers/navigation.js
+++ b/packages/gitbook-core/src/reducers/navigation.js
@@ -1,11 +1,13 @@
-const { Record } = require('immutable');
+const { Record, List } = require('immutable');
 const ACTION_TYPES = require('../actions/TYPES');
 
 const NavigationState = Record({
     // Are we loading a new page
     loading: Boolean(false),
     // Did we fail loading a page?
-    error:   null
+    error:   null,
+    // Listener for history changes
+    listeners: List()
 });
 
 function reduceNavigation(state, action) {
@@ -28,6 +30,11 @@ function reduceNavigation(state, action) {
             error:   action.error
         });
 
+    case ACTION_TYPES.NAVIGATION_LISTEN:
+        return state.merge({
+            listeners: state.listeners.push(action.listener)
+        });
+
     default:
         return state;