Add "output" variables for templating

docs/templating/variables.md

@@ -12,6 +12,7 @@ The following is a reference of the available data during book's parsing and the
 | `file` | File associated with the current page specific information |
 | `summary` | Information about the table of contents |
 | `languages` | List of languages for multi-lingual books |
+| `output` | Information about the output generator |
 | `config` | Dump of the `book.json` |
 
 ### Book Variables
@@ -62,3 +63,11 @@ The whole table of contents (`SUMMARY.md`) can be accessed:
 | `languages.list` | List of languages for this book |
 
 Languages are defined by `{ id: 'en', title: 'English' }`.
+
+### Output Variables
+
+| Variable | Description |
+| -------- | ----------- |
+| `output.name` | Name of the output generator, possible values are `website`, `json`, `ebook` |
+| `output.format` | When `output.name == "ebook"`, `format` defines the ebook format that will be generated, possible values are `pdf`, `epub` or `mobi` |
+

lib/output/base.js

@@ -221,10 +221,19 @@ Output.prototype.onLanguageBook = function(book) {
 
 // ---- Utilities ----
 
+// Return conetxt for the output itself
+Output.prototype.getSelfContext = function() {
+    return {
+        name: this.name
+    };
+};
+
 // Return a default context for templates
 Output.prototype.getContext = function() {
     return _.extend(
-        {},
+        {
+            output: this.getSelfContext()
+        },
         this.book.getContext(),
         this.book.langs.getContext(),
         this.book.summary.getContext(),

lib/output/ebook.js

@@ -21,6 +21,15 @@ var EbookOutput = assetsInliner(_EbookOutput);
 
 EbookOutput.prototype.name = 'ebook';
 
+// Return context for templating
+// Incldue type of ebbook generated
+EbookOutput.prototype.getSelfContext = function() {
+    var ctx = EbookOutput.super_.prototype.getSelfContext.apply(this);
+    ctx.format = this.opts.format;
+
+    return ctx;
+};
+
 // Finish generation, create ebook using ebook-convert
 EbookOutput.prototype.finish = function() {
     var that = this;