Prevent removing a tag being used

7 files changed, 61 insertions, 30 deletions

diff --git a/src/db/init.py b/src/db/init.py
index 6b4cbea..77920cf 100644
--- a/src/db/init.py
+++ b/src/db/init.py
@@ -8,9 +8,9 @@ def init(path):
 
     database = sqlite3.connect(path)
 
-    if is_db_new:
+    cursor = database.cursor()
 
-        cursor = database.cursor()
+    if is_db_new:
 
         cursor.execute(
             " CREATE TABLE IF NOT EXISTS tasks("
@@ -43,6 +43,8 @@ def init(path):
             "   PRIMARY KEY (task_id, tag_id)"
             " )")
 
-        database.commit()
+    cursor.execute("PRAGMA foreign_keys = ON")
+
+    database.commit()
 
     return database
diff --git a/src/db/task_tags.py b/src/db/task_tags.py
index 34366e0..93dc627 100644
--- a/src/db/task_tags.py
+++ b/src/db/task_tags.py
@@ -4,6 +4,15 @@ from typing import List
 
 from model.task_tag import TaskTag
 
+def one_is_used(cursor: Cursor, tag_ids: List[int]) -> bool:
+    if len(tag_ids) >= 1:
+        cursor.execute(
+            "SELECT task_id FROM task_tags WHERE tag_id IN (%s) LIMIT 1" % ",".join("?"*len(tag_ids)),
+            tag_ids)
+        return len(cursor.fetchall()) == 1
+    else:
+        return False
+
 def get(cursor: Cursor) -> List[TaskTag]:
     cursor.execute("SELECT task_id, tag_id FROM task_tags")
     return [TaskTag(r[0], r[1]) for r in cursor.fetchall()]
diff --git a/src/gui/tags/panel/table/menu.py b/src/gui/tags/panel/table/menu.py
index 2238444..6bf812e 100644
--- a/src/gui/tags/panel/table/menu.py
+++ b/src/gui/tags/panel/table/menu.py
@@ -1,25 +1,36 @@
 from PyQt5 import QtWidgets, QtCore
 
+from model.tag import Tag, ValidTagForm
+import database
 import db.tags
+import db.task_tags
 import gui.tags.panel.dialog
-from model.tag import Tag, ValidTagForm
 
 def open(table, update_tag_signal, position):
     rows = set([index.row() for index in table.selectedIndexes()])
 
     menu = QtWidgets.QMenu(table)
 
+    actions = 0
+
     if len(rows) == 1:
         modify_action = menu.addAction(gui.icon.dialog_open(menu.style()), 'modify')
+        actions += 1
     else:
         modify_action = QtWidgets.QAction(menu)
 
-    delete_action = menu.addAction(gui.icon.trash(menu.style()), 'delete')
+    tags = table.model().row_ids(rows)
+    if not db.task_tags.one_is_used(database.cursor(), tags):
+        delete_action = menu.addAction(gui.icon.trash(menu.style()), 'delete')
+        actions += 1
+    else:
+        delete_action = QtWidgets.QAction(menu)
 
-    action = menu.exec_(table.mapToGlobal(position + QtCore.QPoint(15, 20)))
-    if action == modify_action and len(rows) == 1:
-        row = list(rows)[0]
-        tag = table.model().get_at(row)
-        gui.tags.panel.dialog.update(table, update_tag_signal, row, tag).exec_()
-    elif action == delete_action:
-        gui.tags.panel.dialog.show_delete(table, rows)
+    if actions > 0:
+        action = menu.exec_(table.mapToGlobal(position + QtCore.QPoint(15, 20)))
+        if action == modify_action and len(rows) == 1:
+            row = list(rows)[0]
+            tag = table.model().get_at(row)
+            gui.tags.panel.dialog.update(table, update_tag_signal, row, tag).exec_()
+        elif action == delete_action:
+            gui.tags.panel.dialog.show_delete(table, rows)
diff --git a/src/gui/tags/panel/table/model.py b/src/gui/tags/panel/table/model.py
index 7c66b5d..353f747 100644
--- a/src/gui/tags/panel/table/model.py
+++ b/src/gui/tags/panel/table/model.py
@@ -1,5 +1,6 @@
 from PyQt5 import QtCore, QtWidgets, QtGui
 from PyQt5.QtCore import Qt
+from typing import List
 
 from model.tag import Tag
 import time
diff --git a/src/gui/tags/panel/table/widget.py b/src/gui/tags/panel/table/widget.py
index f0bf82c..0ef67c2 100644
--- a/src/gui/tags/panel/table/widget.py
+++ b/src/gui/tags/panel/table/widget.py
@@ -1,13 +1,14 @@
 from PyQt5 import QtWidgets
 from PyQt5.QtCore import Qt
 
+from model.tag import Tag, ValidTagForm
+import database
 import db.tags
+import db.task_tags
+import gui.tags.panel.dialog
 import gui.tags.panel.signal
 import gui.tags.panel.table.menu
 import gui.tags.panel.table.model
-import gui.tags.panel.dialog
-from model.tag import Tag, ValidTagForm
-import database
 
 class Widget(QtWidgets.QTableView):
 
@@ -60,7 +61,9 @@ class Widget(QtWidgets.QTableView):
                 gui.tags.panel.dialog.update(self, self._update_tag_signal, row, tag).exec_()
         elif event.key() == Qt.Key_Delete:
             rows = self.get_selected_rows()
-            gui.tags.panel.dialog.show_delete(self, rows)
+            tags = self.model().row_ids(rows)
+            if not db.task_tags.one_is_used(database.cursor(), tags):
+                gui.tags.panel.dialog.show_delete(self, rows)
 
     def get_selected_rows(self):
         return list(set([index.row() for index in self.selectedIndexes()]))
diff --git a/src/gui/tasks/table/widget.py b/src/gui/tasks/table/widget.py
index 0a8d216..82c0456 100644
--- a/src/gui/tasks/table/widget.py
+++ b/src/gui/tasks/table/widget.py
@@ -99,16 +99,21 @@ class Widget(QtWidgets.QTableWidget):
                 reverse = is_rev)
 
     def update_task(self, row, task: Task, tags: List[int]):
-        # TODO: just update if sort order is not impacted
-        # self._tasks[row] = task
-        # task_ids = [t.id for t in self._tasks]
-        # filtred_task_tags = [tt for tt in self._task_tags if tt.task_id in task_ids]
-        # new_task_tags = [TaskTag(task_id=task.id, tag_id=tag_id) for tag_id in tags]
-        # self._task_tags = filtred_task_tags + new_task_tags
-        # self.update_row(row)
-        self.delete_rows([row])
-        row = self.insert(task, tags)
-        self.selectRow(row)
+        self._tasks[row] = task
+        filtred_task_tags = [tt for tt in self._task_tags if tt.task_id in [t.id for t in self._tasks if t.id != task.id]]
+        new_task_tags = [TaskTag(task_id=task.id, tag_id=tag_id) for tag_id in tags]
+        self._task_tags = filtred_task_tags + new_task_tags
+
+        # Update task in table
+        self.sort()
+        row_after_sort = [i for i in range(len(self._tasks)) if self._tasks[i].id == task.id][0]
+        if row_after_sort == row:
+            self.update_row(row)
+        else:
+            self.removeRow(row)
+            self.insertRow(row_after_sort)
+            self.update_row(row_after_sort)
+            self.selectRow(row_after_sort)
 
     def update_view(self):
         for row in range(len(self._tasks)):
diff --git a/src/service/tasks.py b/src/service/tasks.py
index 6c3444b..870002a 100644
--- a/src/service/tasks.py
+++ b/src/service/tasks.py
@@ -10,18 +10,18 @@ def get(cursor) -> List[Task]:
 
 def create(cursor, task_form: ValidTaskForm) -> Task:
     task = db.tasks.insert(cursor, task_form)
-    new_task_tags = db.task_tags.insert_many(cursor, task.id, task_form.tags)
+    db.task_tags.insert_many(cursor, task.id, task_form.tags)
     database.commit()
     return task
 
 def update(cursor, task: Task, task_form: ValidTaskForm) -> Task:
-    updated_task = db.tasks.update(cursor, task, task_form)
     db.task_tags.delete(cursor, [task.id])
-    new_task_tags = db.task_tags.insert_many(cursor, task.id, task_form.tags)
+    updated_task = db.tasks.update(cursor, task, task_form)
+    db.task_tags.insert_many(cursor, task.id, task_form.tags)
     database.commit()
     return updated_task
 
 def delete(cursor, task_ids: List[int]):
-    db.tasks.delete(cursor, task_ids)
     db.task_tags.delete(cursor, task_ids)
+    db.tasks.delete(cursor, task_ids)
     database.commit()