db_config_dialog.py: add_row():modify to accept nextline in description,...

db_config_dialog.py: add_row():modify to accept nextline in description, return text for next field checking, set placeholdertext as hint for ValueColors; check changes before clicking on 'CLOSE'

sohstationviewer/view/db_config/db_config_dialog.py

 from PySide2 import QtWidgets, QtGui, QtCore
+from typing import Set, Dict
 
 from sohstationviewer.database.process_db import execute_db
 
@@ -73,6 +74,10 @@ class UiDBInfoDialog(QtWidgets.QWidget):
         self.col_name = col_name
         self.table_name = table_name
         self.check_fk = check_fk
+        """
+        changes_by_rowid: dict of changes by row ids
+        """
+        self.changes_by_rowid: Dict[int, Set[int]] = {}
         super(UiDBInfoDialog, self).__init__()
         # =========================== pre-define ============================
         """
@@ -103,7 +108,8 @@ class UiDBInfoDialog(QtWidgets.QWidget):
             main_layout.addWidget(QtWidgets.QLabel(instruction))
 
     def add_widget(self, data_list, row_idx, col_idx, foreign_key=False,
-                   choices=None, range_values=None, field_name=''):
+                   choices=None, range_values=None, field_name='',
+                   place_holder_text='') -> str:
         """
         Add a cell widget at a given row and column in the data_table_widget.
 
@@ -122,6 +128,9 @@ class UiDBInfoDialog(QtWidgets.QWidget):
         :param field_name: name of the column in database. If field_name=
             'convertFactor', add validator to limit precision to 6 decimal
             points
+        :param place_holder_text: the text displayed in QTextEdit as a hint
+            for user
+        :return text: value of the current field in string
         """
         if data_list is None:
             text = str(row_idx)  # row number
@@ -131,7 +140,16 @@ class UiDBInfoDialog(QtWidgets.QWidget):
         if data_list is None:
             widget = QtWidgets.QPushButton(text)
         elif choices is None and range_values is None:
-            widget = QtWidgets.QLineEdit(text)
+            if field_name == 'description':
+                widget = QtWidgets.QTextEdit()
+                height = 12
+                for line in text.split('\n'):
+                    widget.append(line)
+                    height += 16
+                widget.setFixedHeight(height)
+            else:
+                widget = QtWidgets.QLineEdit(text)
+                widget.setPlaceholderText(place_holder_text)
             if field_name == 'convertFactor':
                 # precision=6
                 validator = QtGui.QDoubleValidator(0.0, 5.0, 6)
@@ -175,6 +193,9 @@ class UiDBInfoDialog(QtWidgets.QWidget):
                     lambda changed_text:
                     self.cell_input_change(changed_text, row_idx, col_idx))
         self.data_table_widget.setCellWidget(row_idx, col_idx, widget)
+        if field_name == 'description':
+            self.data_table_widget.resizeRowToContents(row_idx)
+        return text
 
     @QtCore.Slot()
     def row_number_clicked(self, widget):
@@ -217,10 +238,26 @@ class UiDBInfoDialog(QtWidgets.QWidget):
 
         self.close_btn = QtWidgets.QPushButton(self, text='CLOSE')
         self.close_btn.setFixedWidth(300)
-        self.close_btn.clicked.connect(self.close)
+        self.close_btn.clicked.connect(self.on_close)
         h_layout.addWidget(self.close_btn)
         return h_layout
 
+    def on_close(self):
+        if len(self.changes_by_rowid) != 0:
+            msg = ("Some changes may have been created on the table.\n"
+                   "Please click on Cancel to go back save those changes to "
+                   "database.\n"
+                   "OR click on Continue to close the dialog.")
+            msgbox = QtWidgets.QMessageBox()
+            msgbox.setWindowTitle('Do you want to continue?')
+            msgbox.setText(msg)
+            msgbox.addButton(QtWidgets.QMessageBox.Cancel)
+            msgbox.addButton('Continue', QtWidgets.QMessageBox.YesRole)
+            result = msgbox.exec_()
+            if result == QtWidgets.QMessageBox.Cancel:
+                return
+        self.close()
+
     def create_data_table_widget(self):
         """
         Create self.data_table_widget based on self.total_col, self.column
@@ -304,6 +341,17 @@ class UiDBInfoDialog(QtWidgets.QWidget):
                 changed = True
             cell_widget = self.data_table_widget.cellWidget(row_idx, col_idx)
             set_widget_color(cell_widget, changed=changed)
+        else:
+            changed = True
+        if changed:
+            if row_idx not in self.changes_by_rowid:
+                self.changes_by_rowid[row_idx] = set()
+            self.changes_by_rowid[row_idx].add(col_idx - 1)  # skip order col
+        else:
+            try:
+                self.changes_by_rowid[row_idx].remove(col_idx - 1)
+            except KeyError:
+                pass
 
     def check_data_foreign_key(self, val):
         """
@@ -394,6 +442,11 @@ class UiDBInfoDialog(QtWidgets.QWidget):
         row_count = self.data_table_widget.rowCount()
         for i in range(row_count):
             widget_idx = i - (row_count - self.data_table_widget.rowCount())
+            if widget_idx != i and i in self.changes_by_rowid:
+                # row id may not be consistent with widget_idx due to
+                # row row removed or inserted.
+                self.changes_by_rowid.remove(i)
+                self.changes_by_rowid.add(widget_idx)
             list_idx = (i - self.remove_count
                         + self.insert_count - self.skip_count)
             try:
@@ -405,6 +458,11 @@ class UiDBInfoDialog(QtWidgets.QWidget):
             reset = self.update_data(row_inputs, widget_idx, list_idx)
             if reset > -1:
                 self.reset_row_inputs(reset, widget_idx, list_idx)
+            try:
+                if len(self.changes_by_rowid[widget_idx]) == 0:
+                    del self.changes_by_rowid[widget_idx]
+            except KeyError:
+                pass
 
     def update_data(self, row, widget_idx, list_idx, insert_sql, update_sql,
                     del_sql_add=None):
@@ -444,6 +502,7 @@ class UiDBInfoDialog(QtWidgets.QWidget):
                     )
                     cell_widget.setText(org_row[0])
                     row[0] = org_row[0]
+                    self.changes_by_rowid[widget_idx].remove(0)
                     self.update_data(row, widget_idx, list_idx)
                 else:
                     sql = (f"DELETE FROM {self.table_name} "
@@ -451,6 +510,7 @@ class UiDBInfoDialog(QtWidgets.QWidget):
                     if del_sql_add is not None:
                         sql += sql
                     execute_db(sql)
+                    del self.changes_by_rowid[widget_idx]
                     self.data_list.remove(org_row)
                     self.remove_row(widget_idx)
                     self.remove_count += 1
@@ -470,6 +530,7 @@ class UiDBInfoDialog(QtWidgets.QWidget):
                                                                     1)
                     cell_widget.setText(org_row[0])
                     row[0] = org_row[0]
+                    self.changes_by_rowid[widget_idx].remove(0)
                     self.update_data(row, widget_idx, list_idx)
                 else:
                     msg = (f"Row {widget_idx}: {org_row}  has "
@@ -483,6 +544,7 @@ class UiDBInfoDialog(QtWidgets.QWidget):
                     else:
                         execute_db(update_sql % org_row[0])
                         self.data_list[list_idx] = row
+                        del self.changes_by_rowid[widget_idx]
                         return 0
 
         if row[0] == "":
@@ -490,6 +552,7 @@ class UiDBInfoDialog(QtWidgets.QWidget):
                    f"It will be removed.")
             QtWidgets.QMessageBox.information(self, "Error", msg)
             self.remove_row(widget_idx)
+            del self.changes_by_rowid[widget_idx]
             return -1
         blank_required_columns = [self.required_columns[i]
                                   for i in self.required_columns.keys()
@@ -507,8 +570,10 @@ class UiDBInfoDialog(QtWidgets.QWidget):
                    f"Row {widget_idx} will be removed.")
             QtWidgets.QMessageBox.information(self, "Error", msg)
             self.remove_row(widget_idx)
+            del self.changes_by_rowid[widget_idx]
             return -1
         execute_db(insert_sql)
         self.data_list.append(row)
         self.insert_count += 1
+        del self.changes_by_rowid[widget_idx]
         return 0