Parse navigation and progress in parsed page

2 files changed, 111 insertions, 0 deletions

diff --git a/lib/utils/navigation.js b/lib/utils/navigation.js
new file mode 100644
index 0000000..ae4eb9d
--- /dev/null
+++ b/lib/utils/navigation.js
@@ -0,0 +1,64 @@
+var _ = require('lodash');
+
+// Cleans up an article/chapter object
+// remove 'articles' attributes
+function clean(obj) {
+    return obj && _.omit(obj, ['articles']);
+}
+
+function flattenChapters(chapters) {
+    return _.reduce(chapters, function(accu, chapter) {
+        return accu.concat([clean(chapter)].concat(flattenChapters(chapter.articles)));
+    }, []);
+}
+
+// Returns from a summary a map of
+/*
+    {
+        "file/path.md": {
+            prev: ...,
+            next: ...,
+        },
+        ...
+    }
+*/
+function navigation(summary, files) {
+    // Support single files as well as list
+    files = _.isArray(files) ? files : (_.isString(files) ? [files] : null);
+
+    // List of all navNodes
+    // Flatten chapters, then add in default README node if ndeeded etc ...
+    var navNodes = flattenChapters(summary.chapters);
+    var prevNodes = [null].concat(navNodes.slice(0, -1));
+    var nextNodes = navNodes.slice(1).concat([null]);
+
+    // Mapping of prev/next for a give path
+    var mapping = _.chain(_.zip(navNodes, prevNodes, nextNodes))
+    .map(function(nodes) {
+        var current = nodes[0], prev = nodes[1], next = nodes[2];
+
+        // Skip if no path
+        if(!current.path) return null;
+
+        return [current.path, {
+            title: current.title,
+            prev: prev,
+            next: next,
+            level: current.level,
+        }];
+    })
+    .filter()
+    .object()
+    .value();
+
+    // Filter for only files we want
+    if(files) {
+        return _.pick(mapping, files);
+    }
+
+    return mapping;
+}
+
+
+// Exports
+module.exports = navigation;
diff --git a/lib/utils/progress.js b/lib/utils/progress.js
new file mode 100644
index 0000000..b66aea9
--- /dev/null
+++ b/lib/utils/progress.js
@@ -0,0 +1,47 @@
+var _ = require("lodash");
+
+// Returns from a navigation and a current file, a snapshot of current detailed state
+var calculProgress = function(navigation, current) {
+    var n = _.size(navigation);
+    var percent = 0, prevPercent = 0, currentChapter = null;
+    var done = true;
+
+    var chapters = _.chain(navigation)
+    .map(function(nav, path) {
+        nav.path = path;
+        return nav;
+    })
+    .map(function(nav, i) {
+        // Calcul percent
+        nav.percent = (i * 100) / Math.max((n - 1), 1);
+
+        // Is it done
+        nav.done = done;
+        if (nav.path == current) {
+            currentChapter = nav;
+            percent = nav.percent;
+            done = false;
+        } else if (done) {
+            prevPercent = nav.percent;
+        }
+
+        return nav;
+    })
+    .value();
+
+    return {
+        // Previous percent
+        prevPercent: prevPercent,
+
+        // Current percent
+        percent: percent,
+
+        // List of chapter with progress
+        chapters: chapters,
+
+        // Current chapter
+        current: currentChapter
+    };
+}
+
+module.exports = calculProgress;