1 files changed, 61 insertions, 0 deletions
diff --git a/lib/plugins2/compatibility.js b/lib/plugins2/compatibility.js
new file mode 100644
index 0000000..77f4be2
--- /dev/null
+++ b/lib/plugins2/compatibility.js
@@ -0,0 +1,61 @@
+var _ = require('lodash');
+var error = require('../utils/error');
+
+/*
+    Return the context for a plugin.
+    It tries to keep compatibilities with GitBook v2
+*/
+function pluginCtx(plugin) {
+    var book = plugin.book;
+    var ctx = book;
+
+    return ctx;
+}
+
+/*
+    Call a function "fn" with a context of page similar to the one in GitBook v2
+
+    @params {Page}
+    @returns {String|undefined} new content of the page
+*/
+function pageHook(page, fn) {
+    // Get page context
+    var ctx = page.getContext().page;
+
+    // Add other informations
+    ctx.type    = page.type;
+    ctx.rawPath = page.rawPath;
+    ctx.path    = page.path;
+
+    // Deprecate sections
+    error.deprecateField(ctx, 'sections', [
+        { content: ctx.content, type: 'normal' }
+    ], '"sections" property is deprecated, use page.content instead');
+
+    // Keep reference of original content for compatibility
+    var originalContent = ctx.content;
+
+    return fn(ctx)
+    .then(function(result) {
+        // No returned value
+        // Existing content will be used
+        if (!result) return undefined;
+
+        // GitBook 3
+        // Use returned page.content if different from original content
+        if (result.content != originalContent) {
+            return result.content;
+        }
+
+        // GitBook 2 compatibility
+        // Finally, use page.sections
+        if (result.sections) {
+            return _.pluck(result.sections, 'content').join('\n');
+        }
+    });
+}
+
+module.exports = {
+    pluginCtx: pluginCtx,
+    pageHook: pageHook
+};