4 files changed, 93 insertions, 8 deletions

diff --git a/lib/plugin.js b/lib/plugin.js
index bcc861d..99e8402 100644
--- a/lib/plugin.js
+++ b/lib/plugin.js
@@ -101,6 +101,37 @@ Plugin.prototype.getResources = function(base) {
     });
 };
 
+// Normalize filters and return them
+Plugin.prototype.getFilters = function() {
+    var that = this;
+
+    return _.chain(this.infos.filters || {})
+        .map(function(func, key) {
+            if (!_.isString(key)) {
+                that.book.log.warn.ln("Invalid filter '"+key+"' in plugin '"+that.name+"'");
+                return null;
+            }
+
+            return [
+                key,
+                function() {
+                    var ctx = this;
+                    var args = Array.prototype.slice.apply(arguments);
+                    var callback = _.last(args);
+
+                    Q()
+                    .then(function() {
+                        return func.apply(ctx, args.slice(0, -1));
+                    })
+                    .nodeify(callback);
+                }
+            ];
+        })
+        .compact()
+        .object()
+        .value();
+};
+
 // Test if it's a valid plugin
 Plugin.prototype.isValid = function() {
     var that = this;
@@ -175,6 +206,12 @@ Plugin.normalize = function(plugins, generator, options) {
     // The raw resources extracted from each plugin
     var pluginResources;
 
+    // Map of resources
+    var resources = {};
+
+    // Map of all filters
+    var filters = {};
+
     // Get resources of plugins
     return Q.all(_.map(plugins, function(plugin) {
         return plugin.getResources(options.assetsBase);
@@ -182,17 +219,20 @@ Plugin.normalize = function(plugins, generator, options) {
 
     // Extract resources out
     // css, js, etc ...
-    .then(function(resources) {
-        pluginResources = resources;
+    .then(function(_resources) {
+        pluginResources = _resources;
+    })
+    .then(function() {
         // Group by resource types
-        return _.chain(Plugin.RESOURCES)
+        resources = _.chain(Plugin.RESOURCES)
         .map(function(resourceType) {
             // Get resources from all the plugins for this current type
             return [
                 // Key
                 resourceType,
+
                 // Value
-                _.chain(resources)
+                _.chain(pluginResources)
                 .pluck(resourceType)
                 .compact()
                 .flatten()
@@ -202,8 +242,9 @@ Plugin.normalize = function(plugins, generator, options) {
         .object()
         .value();
     })
+
     // Extract html snippets
-    .then(function(resources) {
+    .then(function() {
         // Map of html resources by name added by each plugin
         resources.html = pluginResources.reduce(function(accu, resource) {
             var html = (resource && resource.html) || {};
@@ -216,14 +257,27 @@ Plugin.normalize = function(plugins, generator, options) {
 
             return accu;
         }, {});
+    })
 
-        return resources;
+    // Extract filters
+    .then(function() {
+        _.each(plugins, function(plugin) {
+            _.each(plugin.getFilters(), function(filterFunc, filterName) {
+                if (filters[filterName]) {
+                    plugin.book.log.warn.ln("Conflict in filters, '"+filterName+"' is already set");
+                } else {
+                    filters[filterName] = filterFunc;
+                }
+            });
+        });
     })
-    // Return big multi-plugin object
-    .then(function(resources) {
+
+    // Return big multi-plugins object
+    .then(function() {
         return {
             'list': plugins,
             'resources': resources,
+            'filters': filters,
             'hook': function(name, data) {
                 return _.reduce(plugins, function(prev, plugin) {
                     return prev.then(function(ret) {
diff --git a/test/plugins.js b/test/plugins.js
index f75af34..cd46246 100644
--- a/test/plugins.js
+++ b/test/plugins.js
@@ -35,4 +35,19 @@ describe('Plugins', function () {
                 done);
         });
     });
+
+    describe('filters', function() {
+        var plugin = new Plugin(books[0], "filters");
+        plugin.load("./filters", PLUGINS_ROOT);
+
+        it('should valid a plugin', function() {
+            assert(plugin.isValid());
+        });
+
+        it('should return a map of filters', function() {
+            var filters = plugin.getFilters();
+            assert.equal(_.size(filters), 1);
+            assert(filters["hello"]);
+        });
+    });
 });
diff --git a/test/plugins/filters/index.js b/test/plugins/filters/index.js
new file mode 100644
index 0000000..0087ba1
--- /dev/null
+++ b/test/plugins/filters/index.js
@@ -0,0 +1,7 @@
+module.exports = {
+    filters: {
+        hello: function(text) {
+            return "Hello "+text;
+        }
+    }
+};
\ No newline at end of file
diff --git a/test/plugins/filters/package.json b/test/plugins/filters/package.json
new file mode 100644
index 0000000..f1d4e45
--- /dev/null
+++ b/test/plugins/filters/package.json
@@ -0,0 +1,9 @@
+{
+    "name": "gitbook-plugin-filters",
+    "description": "Test filters",
+    "main": "index.js",
+    "version": "0.0.1",
+    "engines": {
+        "gitbook": "*"
+    }
+}
\ No newline at end of file