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LWS এসাইনমেন্ট ৩ঃ প্রোজেক্ট ম্যানেজার
State Logic Wrong and Fixed by Chatgpt

Great job on structuring your taskReducer logic. You're very close, but there are two small issues in your "EDITED_TASK" section that could lead to bugs:

❌ Mistake 1: Using action.taskId in edited logic

You're doing this:

tasks[oldCategory].filter((task) => task.id !== action.taskId);

But action.taskId is not passed in the EDITED_TASK payload — you already have the full action.task, so you should access action.task.id.

❌ Mistake 2: Not handling unknown action types

Your reducer doesn't have a fallback return tasks; if the action type doesn't match. This could cause issues if an unexpected action is dispatched.

✅ Corrected Version

export default function taskReducer(tasks, action) {
  if (action.type === "ADDED_TASK") {
    const category = action.category;
    return {
      ...tasks,
      [category]: [...tasks[category], action.task],
    };
  } else if (action.type === "REMOVED_TASK") {
    const category = action.category;
    return {
      ...tasks,
      [category]: tasks[category].filter((task) => task.id !== action.taskId),
    };
  } else if (action.type === "EDITED_TASK") {
    const category = action.category; // new category
    const oldCategory = action.editedCategory; // previous category
 
    // ✅ If category changed
    if (category !== oldCategory) {
      return {
        ...tasks,
        [oldCategory]: tasks[oldCategory].filter(
          (task) => task.id !== action.task.id
        ), // ❗ fixed
        [category]: [...tasks[category], action.task],
      };
    }
 
    // ✅ If category not changed
    return {
      ...tasks,
      [category]: tasks[category].map((taskItem) =>
        taskItem.id === action.task.id ? action.task : taskItem
      ),
    };
  }
 
  // ✅ Fallback for unknown action type
  return tasks;
}

✅ Summary of Fixes

ProblemFix
Used action.taskId in EDITED_TASKReplaced with action.task.id
No fallback returnAdded return tasks; at the end

Would you like me to show example dispatch actions for each case (add, remove, edit)?

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