From 503159c5d5a27cc50931ea73762ff58a4853287c Mon Sep 17 00:00:00 2001
From: Rodney <rodney.baker@gmail.com>
Date: Jan 21 2022 04:12:33 +0000
Subject: Merge pull request #4227 from shun-iwasawa/fix_implicit_cell_dragging


Fix implicit hold cell dragging
---

diff --git a/toonz/sources/toonz/xshcellmover.cpp b/toonz/sources/toonz/xshcellmover.cpp
index ce8c290..787174f 100644
--- a/toonz/sources/toonz/xshcellmover.cpp
+++ b/toonz/sources/toonz/xshcellmover.cpp
@@ -74,6 +74,9 @@ void CellsMover::start(int r0, int c0, int r1, int c1, int qualifiers,
   m_oldCells.resize(m_rowCount * m_colCount, TXshCell());
   getCells(m_cells, r0, c0);
   getColumnsData(c0, c1);
+
+  if (m_qualifiers & eInsertCells && !(m_qualifiers & eOverwriteCells))
+    getImplicitCellInfo();
 }
 
 //
@@ -84,6 +87,46 @@ TXsheet *CellsMover::getXsheet() const {
 }
 
 //
+// keeping the implicit cell arrangement when start shift + dragging
+//
+
+void CellsMover::getImplicitCellInfo() {
+  int startCol =
+      (m_orientation->isVerticalTimeline()) ? m_startPos.x : m_startPos.y;
+  int startRow =
+      (m_orientation->isVerticalTimeline()) ? m_startPos.y : m_startPos.x;
+
+  TXsheet *xsh = getXsheet();
+  for (int i = 0; i < m_colCount; i++) {
+    TXshColumn *column = xsh->getColumn(startCol + i);
+    if (!column || column->getCellColumn() == 0 || column->isLocked()) continue;
+    TXshCellColumn *cellCol = column->getCellColumn();
+    QMap<int, TXshCell> cellInfo;
+    if (!column->isEmpty()) {
+      int r0, r1;
+      column->getRange(r0, r1);
+      TXshCell currentCell;
+      for (int r = r0; r <= r1 + 1; r++) {
+        TXshCell tmpCell = cellCol->getCell(r);
+        if (tmpCell != currentCell) {
+          if (m_qualifiers & eCopyCells)
+            cellInfo.insert(r, tmpCell);
+          else {
+            if (r < startRow)
+              cellInfo.insert(r, tmpCell);
+            else if (r >= startRow + m_rowCount)
+              cellInfo.insert(r - m_rowCount, tmpCell);
+          }
+          currentCell = tmpCell;
+        }
+      }
+    }
+
+    m_implicitCellInfo.append(cellInfo);
+  }
+}
+
+//
 // cells <- xsheet
 //
 
@@ -152,21 +195,25 @@ void CellsMover::moveCells(const TPoint &pos) const {
     int startCol =
         (m_orientation->isVerticalTimeline()) ? m_startPos.x : m_startPos.y;
     if (startCol == c) {
+      int infoId = 0;
       for (int i = 0; i < m_colCount; i++) {
         TXshColumn *column = xsh->getColumn(c + i);
         if (!column || column->getCellColumn() == 0 || column->isLocked())
           continue;
-        // a cell above inserted cells
-        TXshCell upperCell = xsh->getCell(r - 1, c + i);
-        if (upperCell.isEmpty()) continue;
+
+        QMap<int, TXshCell>::const_iterator itr =
+            m_implicitCellInfo[infoId].lowerBound(r);
+        if (itr == m_implicitCellInfo[infoId].end() || itr.key() == r) {
+          infoId++;
+          continue;
+        }
         // a cell at the bottom of the inserted cells
         TXshCell bottomCell = xsh->getCell(r + m_rowCount - 1, c + i);
-        if (bottomCell.isEmpty()) continue;
-        int tmp_r = r + m_rowCount;
-        while (xsh->getCell(tmp_r, c + i) == upperCell) {
+        for (int tmp_r = r + m_rowCount; tmp_r <= itr.key() - 1 + m_rowCount;
+             tmp_r++)
           xsh->setCell(tmp_r, c + i, bottomCell);
-          tmp_r++;
-        }
+
+        infoId++;
       }
     }
   }
@@ -180,6 +227,7 @@ void CellsMover::undoMoveCells(const TPoint &pos) const {
     r = pos.x;
     c = pos.y;
   }
+
   if (m_qualifiers & eInsertCells) {
     // Act like implicit hold when dragging cells with pressing Shift key
     // ( and WITHOUT Alt key ) and dragging within the same column.
@@ -187,19 +235,27 @@ void CellsMover::undoMoveCells(const TPoint &pos) const {
       int startCol =
           (m_orientation->isVerticalTimeline()) ? m_startPos.x : m_startPos.y;
       if (startCol == c) {
+        int infoId = 0;
         for (int i = 0; i < m_colCount; i++) {
-          // a cell above selected cells
-          TXshCell upperCell = xsh->getCell(r - 1, c + i);
-          if (upperCell.isEmpty()) continue;
-          // a cell at the bottom of the selected cells
-          TXshCell bottomCell = xsh->getCell(r + m_rowCount - 1, c + i);
-          if (bottomCell.isEmpty()) continue;
-          int tmp_r = r + m_rowCount;
-          while (xsh->getCell(tmp_r, c + i) == bottomCell) {
-            xsh->setCell(tmp_r, c + i, upperCell);
-            tmp_r++;
+          TXshColumn *column = xsh->getColumn(c + i);
+          if (!column || column->getCellColumn() == 0 || column->isLocked())
+            continue;
+
+          // clear the cells and restore original arrangement
+          TXshCellColumn *cellCol = column->getCellColumn();
+          int r0, r1;
+          cellCol->getRange(r0, r1);
+          cellCol->clearCells(r0, r1 - r0 + 1);
+          QList<int> implicitKeys = m_implicitCellInfo[infoId].keys();
+          for (int k = 0; k < implicitKeys.size() - 1; k++) {
+            int from = implicitKeys[k];
+            int to   = implicitKeys[k + 1] - 1;
+            for (int f = from; f <= to; f++)
+              cellCol->setCell(f, m_implicitCellInfo[infoId].value(from));
           }
+          infoId++;
         }
+        return;
       }
     }
 
@@ -589,7 +645,9 @@ void LevelMoverTool::onCellChange(int row, int col) {
 
   m_validPos = canMoveColumns(pos);
   if (!m_validPos) return;
-  if (m_moved) cellsMover->undoMoveCells();
+  if (m_moved) {
+    cellsMover->undoMoveCells();
+  }
   m_validPos = canMove(pos);
 
   if (m_validPos) {
diff --git a/toonz/sources/toonz/xshcellmover.h b/toonz/sources/toonz/xshcellmover.h
index 28d36bd..2f98714 100644
--- a/toonz/sources/toonz/xshcellmover.h
+++ b/toonz/sources/toonz/xshcellmover.h
@@ -33,6 +33,9 @@ class CellsMover {
 
   const Orientation *m_orientation;
 
+  // keeping the implicit cell arrangement when start shift + dragging
+  QList<QMap<int, TXshCell>> m_implicitCellInfo;
+
   // helper method
   TXsheet *getXsheet() const;
 
@@ -45,6 +48,8 @@ class CellsMover {
   // m_columnsData <- xsheet columns data
   void getColumnsData(int c0, int c1);
 
+  void getImplicitCellInfo();
+
 public:
   enum Qualifier {
     eCopyCells   = 0x1,  // leaves a copy of cells block at the starting point