From a8a79712ef2af310bac56bb807c2bdb77c910b6b Mon Sep 17 00:00:00 2001
From: James Ketrenos <james_git@ketrenos.com>
Date: Wed, 5 Sep 2018 10:29:24 -0700
Subject: [PATCH] Binary sort

Signed-off-by: James Ketrenos <james_git@ketrenos.com>
---
 frontend/src/ketr-photos/ketr-photos.html | 28 +++++++++++++++--------
 1 file changed, 18 insertions(+), 10 deletions(-)

diff --git a/frontend/src/ketr-photos/ketr-photos.html b/frontend/src/ketr-photos/ketr-photos.html
index 199d6b5..847eab2 100755
--- a/frontend/src/ketr-photos/ketr-photos.html
+++ b/frontend/src/ketr-photos/ketr-photos.html
@@ -341,14 +341,12 @@
               return;
             }
 
-            var index, length = this.thumbnails.length - 1;
-
-This needs to become a binary sort between min/max set by either visibleThumbs, or the full
-array. 'index' adjustments then need to be done based on these values instead of on the full
-array or the search can end up bouncing over the 'visible' items
+            var index, start, stop, length = this.thumbnails.length - 1;
 
+            start = 0;
+            stop = this.thumbnails.length - 1;
             if (this.visibleThumbs.length) {
-              index = this.visibleThumbs[this.visibleThumbs.length >> 1];
+              index = this.visibleThumbs[stop >> 1];
             } else {
               index = length >> 1;
             }
@@ -357,10 +355,20 @@ array or the search can end up bouncing over the 'visible' items
             while (pos != 0 && last != index) {
               last = index; /* safety escape in case the DOM changed and nothing matches */
 
-              if (pos == +1) { /* Checked item was too low on the page, so look closer to start */
-                index = index >> 1;
-              } else { /* Checked item was too high on the page, so look farther */
-                index += (length - index) >> 1;
+              if (pos == +1) { /* Checked item was too far down page, so look closer to start */
+                stop = index - 1;
+                if (stop < 0) {
+                  console.log("No items in viewport -- all are below");
+                  return;
+                }
+                index = start + ((stop - start) >> 1);
+              } else { /* Checked item was too high up on the page, so look farther */
+                start = index + 1;
+                if (start == length) {
+                  console.log("No items in viewport -- all are above");
+                  return;
+                }
+                index += (stop - start) >> 1;
               }
 
               pos = this.checkPosition(index);