3 files changed, 81 insertions, 61 deletions
diff --git a/lib/parse/index.js b/lib/parse/index.js
index ec98347..0e333e4 100644
--- a/lib/parse/index.js
+++ b/lib/parse/index.js
@@ -2,6 +2,7 @@ module.exports = {
     summary: require('./summary'),
     langs: require('./langs'),
     page: require('./page'),
+    lex: require('./lex'),
     progress: require('./progress'),
     navigation: require('./navigation'),
 };
diff --git a/lib/parse/lex.js b/lib/parse/lex.js
new file mode 100644
index 0000000..6b3236e
--- /dev/null
+++ b/lib/parse/lex.js
@@ -0,0 +1,74 @@
+var _ = require('lodash');
+var marked = require('marked');
+
+// Split a page up into sections (lesson, exercises, ...)
+function splitSections(nodes) {
+    var section = [];
+
+    return _.reduce(nodes, function(sections, el) {
+        if(el.type === 'hr') {
+            sections.push(section);
+            section = [];
+        } else {
+            section.push(el);
+        }
+
+        return sections;
+    }, []).concat([section]); // Add remaining nodes
+}
+
+// What is the type of this section
+function sectionType(nodes, idx) {
+    var codeNodes = _.filter(nodes, {
+        type: 'code'
+    }).length;
+
+    if(codeNodes === 3 && (idx % 2) == 1) {
+        return 'exercise';
+    }
+
+    return 'normal';
+}
+
+// Generate a uniqueId to identify this section in our code
+function sectionId(section, idx) {
+    return _.uniqueId('gitbook_');
+}
+
+function lexPage(src) {
+    // Lex file
+    var nodes = marked.lexer(src);
+
+    return _.chain(splitSections(nodes))
+    .map(function(section, idx) {
+        // Detect section type
+        section.type = sectionType(section, idx);
+        return section;
+    })
+    .map(function(section, idx) {
+        // Give each section an ID
+        section.id = sectionId(section, idx);
+        return section;
+
+    })
+    .filter(function(section) {
+        return !_.isEmpty(section);
+    })
+    .reduce(function(sections, section) {
+        var last = _.last(sections);
+
+        // Merge normal sections together
+        if(last && last.type === section.type && last.type === 'normal') {
+            last.push.apply(last, [{'type': 'hr'}].concat(section));
+        } else {
+            // Add to list of sections
+            sections.push(section);
+        }
+
+        return sections;
+    }, [])
+    .value();
+}
+
+// Exports
+module.exports = lexPage;
diff --git a/lib/parse/page.js b/lib/parse/page.js
index b17f593..56a9e60 100644
--- a/lib/parse/page.js
+++ b/lib/parse/page.js
@@ -2,6 +2,7 @@ var _ = require('lodash');
 var marked = require('marked');
 var hljs = require('highlight.js');
 
+var lex = require('./lex');
 var renderer = require('./renderer');
 
 var lnormalize = require('../utils/lang').normalize;
@@ -19,35 +20,6 @@ marked.setOptions({
 });
 
 
-// Split a page up into sections (lesson, exercises, ...)
-function splitSections(nodes) {
-    var section = [];
-
-    return _.reduce(nodes, function(sections, el) {
-        if(el.type === 'hr') {
-            sections.push(section);
-            section = [];
-        } else {
-            section.push(el);
-        }
-
-        return sections;
-    }, []).concat([section]); // Add remaining nodes
-}
-
-// What is the type of this section
-function sectionType(nodes, idx) {
-    var codeNodes = _.filter(nodes, {
-        type: 'code'
-    }).length;
-
-    if(codeNodes === 3 && (idx % 2) == 1) {
-        return 'exercise';
-    }
-
-    return 'normal';
-}
-
 // Render a section using our custom renderer
 function render(section, _options) {
     // Copy section
@@ -67,35 +39,9 @@ function render(section, _options) {
 function parsePage(src, options) {
     options = options || {};
 
-    // Lex file
-    var nodes = marked.lexer(src);
-
-    return _.chain(splitSections(nodes))
-    .map(function(section, idx) {
-        // Detect section type
-        section.type = sectionType(section, idx);
-        return section;
-    })
-    .filter(function(section) {
-        return !_.isEmpty(section);
-    })
-    .reduce(function(sections, section) {
-        var last = _.last(sections);
-
-        // Merge normal sections together
-        if(last && last.type === section.type && last.type === 'normal') {
-            last.push.apply(last, [{'type': 'hr'}].concat(section));
-        } else {
-            // Add to list of sections
-            sections.push(section);
-        }
-
-        return sections;
-    }, [])
+    // Lex if not already lexed
+    return (_.isArray(src) ? src : lex(src))
     .map(function(section) {
-        // Generate a uniqueId to identify this section in our code
-        var id = _.uniqueId('gitbook_');
-
         // Transform given type
         if(section.type === 'exercise') {
             var nonCodeNodes = _.reject(section, {
@@ -118,7 +64,7 @@ function parsePage(src, options) {
             var lang = validLangs ? langs[0] : null;
 
             return {
-                id: id,
+                id: section.id,
                 type: section.type,
                 content: render(nonCodeNodes),
                 lang: lang,
@@ -132,12 +78,11 @@ function parsePage(src, options) {
 
         // Render normal pages
         return {
-            id: id,
+            id: section.id,
             type: section.type,
             content: render(section, options)
         };
-    })
-    .value();
+    });
 }
 
 // Exports