From c10f7b61341c36e093930755275ff735f17b1dea Mon Sep 17 00:00:00 2001
From: Martin Filser <github-wekan@linux-email.de>
Date: Tue, 17 May 2022 00:14:10 +0200
Subject: [PATCH 1/3] Utils#calculateIndex re-uses the logic of
 Utils#calculateIndexData

- nearly the same implementation, so use common code base
---
 client/lib/utils.js | 34 ++++++++--------------------------
 1 file changed, 8 insertions(+), 26 deletions(-)

diff --git a/client/lib/utils.js b/client/lib/utils.js
index 6444fdef6..7c3a18aaa 100644
--- a/client/lib/utils.js
+++ b/client/lib/utils.js
@@ -356,34 +356,16 @@ Utils = {
 
   // Determine the new sort index
   calculateIndex(prevCardDomElement, nextCardDomElement, nCards = 1) {
-    let base, increment;
-    // If we drop the card to an empty column
-    if (!prevCardDomElement && !nextCardDomElement) {
-      base = 0;
-      increment = 1;
-      // If we drop the card in the first position
-    } else if (!prevCardDomElement) {
-      base = Blaze.getData(nextCardDomElement).sort - 1;
-      increment = -1;
-      // If we drop the card in the last position
-    } else if (!nextCardDomElement) {
-      base = Blaze.getData(prevCardDomElement).sort + 1;
-      increment = 1;
+    let prevData = null;
+    let nextData = null;
+    if (prevCardDomElement) {
+      prevData = Blaze.getData(prevCardDomElement)
     }
-    // In the general case take the average of the previous and next element
-    // sort indexes.
-    else {
-      const prevSortIndex = Blaze.getData(prevCardDomElement).sort;
-      const nextSortIndex = Blaze.getData(nextCardDomElement).sort;
-      increment = (nextSortIndex - prevSortIndex) / (nCards + 1);
-      base = prevSortIndex + increment;
+    if (nextCardDomElement) {
+      nextData = Blaze.getData(nextCardDomElement);
     }
-    // XXX Return a generator that yield values instead of a base with a
-    // increment number.
-    return {
-      base,
-      increment,
-    };
+    const ret = Utils.calculateIndexData(prevData, nextData, nCards);
+    return ret;
   },
 
   manageCustomUI() {

From 7e8073d6213ea3970f0e4a46e68179c614c5b126 Mon Sep 17 00:00:00 2001
From: Martin Filser <github-wekan@linux-email.de>
Date: Tue, 17 May 2022 00:15:00 +0200
Subject: [PATCH 2/3] after moving, e.g. the minicard, round the index to the
 next integer

- before: at index -1           and -9 the new index was -5
- now   : at index -1 (or -1.1) and -9 the new index is  -2
---
 client/lib/utils.js | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/client/lib/utils.js b/client/lib/utils.js
index 7c3a18aaa..321ee3090 100644
--- a/client/lib/utils.js
+++ b/client/lib/utils.js
@@ -343,8 +343,25 @@ Utils = {
     else {
       const prevSortIndex = prevData.sort;
       const nextSortIndex = nextData.sort;
-      increment = (nextSortIndex - prevSortIndex) / (nItems + 1);
-      base = prevSortIndex + increment;
+      if (nItems == 1 ) {
+        if (prevSortIndex < 0 ) {
+          const ceil = Math.ceil(nextSortIndex - 1);
+          if (ceil < nextSortIndex && ceil > prevSortIndex) {
+            increment = ceil - prevSortIndex;
+          }
+        } else {
+          const floor = Math.floor(nextSortIndex - 1);
+          if (floor < nextSortIndex && floor > prevSortIndex) {
+            increment = floor - prevSortIndex;
+          }
+        }
+      }
+      if (!increment) {
+        increment = (nextSortIndex - prevSortIndex) / (nItems + 1);
+      }
+      if (!base) {
+        base = prevSortIndex + increment;
+      }
     }
     // XXX Return a generator that yield values instead of a base with a
     // increment number.

From b869e3efb6a7e90d1e9c441875cb56bb492ea3e7 Mon Sep 17 00:00:00 2001
From: Martin Filser <github-wekan@linux-email.de>
Date: Wed, 27 Jul 2022 21:24:00 +0200
Subject: [PATCH 3/3] after moving, e.g. minicards, to the list start / end the
 index is rounded to the next index

---
 client/lib/utils.js | 22 ++++++++++++++++++----
 1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/client/lib/utils.js b/client/lib/utils.js
index 321ee3090..8cfd30426 100644
--- a/client/lib/utils.js
+++ b/client/lib/utils.js
@@ -331,12 +331,26 @@ Utils = {
       increment = 1;
       // If we drop the card in the first position
     } else if (!prevData) {
-      base = nextData.sort - 1;
-      increment = -1;
+      const nextSortIndex = nextData.sort;
+      const ceil = Math.ceil(nextSortIndex - 1);
+      if (ceil < nextSortIndex) {
+        increment = nextSortIndex - ceil;
+        base = nextSortIndex - increment;
+      } else {
+        base = nextData.sort - 1;
+        increment = -1;
+      }
       // If we drop the card in the last position
     } else if (!nextData) {
-      base = prevData.sort + 1;
-      increment = 1;
+      const prevSortIndex = prevData.sort;
+      const floor = Math.floor(prevSortIndex + 1);
+      if (floor > prevSortIndex) {
+        increment = prevSortIndex - floor;
+        base = prevSortIndex - increment;
+      } else {
+        base = prevData.sort + 1;
+        increment = 1;
+      }
     }
     // In the general case take the average of the previous and next element
     // sort indexes.