From c139215603c2a76fd05e3220ed8d0343d547e3b0 Mon Sep 17 00:00:00 2001
From: Keith Edmunds <kae@tiger-computing.co.uk>
Date: Sat, 22 Jun 2024 21:52:08 +0100
Subject: [PATCH] Improve drag and drop targetting

---
 app/playlists.py    |  16 ++++++-
 archive/dragdrop.py | 101 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 115 insertions(+), 2 deletions(-)
 create mode 100755 archive/dragdrop.py

diff --git a/app/playlists.py b/app/playlists.py
index 8f49172..d77a1ac 100644
--- a/app/playlists.py
+++ b/app/playlists.py
@@ -271,8 +271,20 @@ class PlaylistTab(QTableView):
 
         from_rows = self.selected_model_row_numbers()
         to_index = self.indexAt(event.position().toPoint())
-        to_model_row = self.proxy_model.mapToSource(to_index).row()
-        log.info(f"PlaylistTab.dropEvent(): {from_rows=}, {to_index=}, {to_model_row=}")
+        if (
+            self.dropIndicatorPosition()
+            == QAbstractItemView.DropIndicatorPosition.BelowItem
+        ):
+            internal_id = to_index.internalId()
+            proxy_index = self.proxy_model.createIndex(
+                to_index.row() + 1, to_index.column(), internal_id
+            )
+        else:
+            proxy_index = to_index
+        to_model_row = self.proxy_model.mapToSource(proxy_index).row()
+        log.info(
+            f"PlaylistTab.dropEvent(): {from_rows=}, {proxy_index=}, {to_model_row=}"
+        )
 
         if (
             0 <= min(from_rows) <= self.source_model.rowCount()
diff --git a/archive/dragdrop.py b/archive/dragdrop.py
new file mode 100755
index 0000000..ce00b48
--- /dev/null
+++ b/archive/dragdrop.py
@@ -0,0 +1,101 @@
+#!/usr/bin/env python3
+
+# https://stackoverflow.com/questions/26227885/drag-and-drop-rows-within-qtablewidget
+
+import sys
+
+from PyQt6.QtWidgets import (
+    QTableWidget,
+    QAbstractItemView,
+    QTableWidgetItem,
+    QWidget,
+    QHBoxLayout,
+    QApplication,
+)
+from PyQt6.QtCore import Qt
+
+
+class TableWidgetDragRows(QTableWidget):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        self.setDragEnabled(True)
+        self.setAcceptDrops(True)
+        self.viewport().setAcceptDrops(True)
+        self.setDragDropOverwriteMode(False)
+        self.setDropIndicatorShown(True)
+
+        self.setSelectionMode(QAbstractItemView.SelectionMode.ExtendedSelection)
+        self.setSelectionBehavior(QAbstractItemView.SelectionBehavior.SelectRows)
+        self.setDragDropMode(QAbstractItemView.DragDropMode.InternalMove)
+        self.DropIndicatorPosition(QAbstractItemView.DropIndicatorPosition.BelowItem)
+
+    def dropEvent(self, event):
+        if event.source() == self:
+            rows = set([mi.row() for mi in self.selectedIndexes()])
+            targetRow = self.indexAt(event.position().toPoint()).row()
+            if self.dropIndicatorPosition() == QAbstractItemView.DropIndicatorPosition.BelowItem:
+                targetRow += 1
+            rows.discard(targetRow)
+            rows = sorted(rows)
+            if not rows:
+                return
+            if targetRow == -1:
+                targetRow = self.rowCount()
+            for _ in range(len(rows)):
+                self.insertRow(targetRow)
+            rowMapping = dict()  # Src row to target row.
+            for idx, row in enumerate(rows):
+                if row < targetRow:
+                    rowMapping[row] = targetRow + idx
+                else:
+                    rowMapping[row + len(rows)] = targetRow + idx
+            colCount = self.columnCount()
+            for srcRow, tgtRow in sorted(rowMapping.items()):
+                for col in range(0, colCount):
+                    self.setItem(tgtRow, col, self.takeItem(srcRow, col))
+            for row in reversed(sorted(rowMapping.keys())):
+                self.removeRow(row)
+            event.accept()
+            return
+
+
+class Window(QWidget):
+    def __init__(self):
+        super(Window, self).__init__()
+
+        layout = QHBoxLayout()
+        self.setLayout(layout)
+
+        self.table_widget = TableWidgetDragRows()
+        layout.addWidget(self.table_widget)
+
+        # setup table widget
+        self.table_widget.setColumnCount(2)
+        self.table_widget.setHorizontalHeaderLabels(["Type", "Name"])
+
+        items = [
+            ("Red", "Toyota"),
+            ("Blue", "RV"),
+            ("Green", "Beetle"),
+            ("Silver", "Chevy"),
+            ("Black", "BMW"),
+        ]
+        self.table_widget.setRowCount(len(items))
+        for i, (color, model) in enumerate(items):
+            item_flags = Qt.ItemFlag.ItemIsSelectable | Qt.ItemFlag.ItemIsDragEnabled
+            colour_item = QTableWidgetItem(color)
+            colour_item.setFlags(item_flags)
+            model_item = QTableWidgetItem(model)
+            model_item.setFlags(item_flags)
+            self.table_widget.setItem(i, 0, QTableWidgetItem(color))
+            self.table_widget.setItem(i, 1, QTableWidgetItem(model))
+
+        self.resize(400, 400)
+        self.show()
+
+
+if __name__ == "__main__":
+    app = QApplication(sys.argv)
+    window = Window()
+    sys.exit(app.exec())