From d292534e9c8474c3c0d5434f77ed9b3d97638695 Mon Sep 17 00:00:00 2001
From: Timur Demin <me@tdem.in>
Date: Sat, 8 Jun 2019 19:21:35 +0500
Subject: [PATCH] Add task manipulation helpers

---
 project_amber/const.py        |  2 ++
 project_amber/helpers/task.py | 39 +++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)
 create mode 100644 project_amber/helpers/task.py

diff --git a/project_amber/const.py b/project_amber/const.py
index bf5bb53..33bd46f 100644
--- a/project_amber/const.py
+++ b/project_amber/const.py
@@ -1,3 +1,5 @@
 from json import dumps
 
 EMPTY_RESP = dumps({}) # Empty response, to be used in requests.
+
+TASK_MSG_NOT_FOUND = "This task does not exist."
diff --git a/project_amber/helpers/task.py b/project_amber/helpers/task.py
new file mode 100644
index 0000000..0bf28cc
--- /dev/null
+++ b/project_amber/helpers/task.py
@@ -0,0 +1,39 @@
+from time import time
+
+from project_amber.const import TASK_MSG_NOT_FOUND
+from project_amber.db import db
+from project_amber.errors import NotFound
+from project_amber.models.task import Task
+
+def addTask(text: str, uid: int) -> int:
+    """
+    Creates a new task. Returns its ID.
+    """
+    task = Task(owner=uid, text=text, creation_time=time(), \
+        last_mod_time=time())
+    db.session.add(task)
+    db.session.commit()
+    return task.id
+
+def updateTask(new_text: str, task_id: int, uid: int) -> int:
+    """
+    Updates the task text. Returns its ID.
+    """
+    task = db.session.query(Task).filter_by(id=task_id, owner=uid).first()
+    if task is None:
+        raise NotFound(TASK_MSG_NOT_FOUND)
+    task.text = new_text
+    db.session.commit()
+    return task_id
+
+
+def removeTask(task_id: int, uid: int) -> int:
+    """
+    Removes a task. Returns its ID on success.
+    """
+    task = db.session.query(Task).filter_by(id=task_id, owner=uid).first()
+    if task is None:
+        raise NotFound(TASK_MSG_NOT_FOUND)
+    db.session.delete(task)
+    db.session.commit()
+    return task_id