# Dev Log: Fix Seller Name Display and Cursor Issues

**Date:** 2026-02-03
**Task:** Fix Seller Name overwriting issue and remove confusing question mark cursor.
**Status:** Successful

## Overview
This task addressed two user-reported issues:
1.  **Seller Name Regression:** The "Seller Name" in the deal details overlay was frequently displaying as a raw Seller ID (e.g., `A3B8AMFZ4FQ0C8`) instead of the human-readable text (e.g., `textgood`). This was identified as a regression likely caused by optimization efforts to reduce API token usage.
2.  **Confusing UI:** Hovering over truncated text (like titles or names) displayed a "question mark" cursor (`cursor: help`), which users found confusing as clicking didn't open a help menu.

## Challenges & Context
The core challenge lay in the system's "Lightweight Update" strategy. To conserve Keepa API tokens, the `Backfiller` and `Simple Task` (Upserter) perform "light" fetches for existing deals, retrieving only the latest stats without full seller details (which cost extra tokens).

*   **The Problem:** The `_process_lightweight_update` function in `keepa_deals/processing.py` was receiving the raw `sellerId` from the lightweight API response. Since it didn't have the seller's *name* (which requires a separate, expensive fetch), it was defaulting to using the ID. It then unconditionally overwrote the `Seller` field in the database with this ID, effectively erasing the human-readable name that had been captured during the initial "Heavy" fetch.

*   **The Constraint:** We could not simply "fetch the name" every time, as that would significantly increase token consumption and re-introduce the "Token Starvation" issues we recently solved.

## Solution

### 1. Backend Logic (Smart Preservation)
We implemented a "Smart Preservation" strategy in `keepa_deals/processing.py`.

*   **Persist the ID:** We modified `_process_single_deal` (the initial heavy fetch) to explicitly save the `sellerId` into a dedicated `Seller ID` column, separate from the `Seller` (display name) column.
*   **Conditional Overwrite:** In `_process_lightweight_update`, we added logic to check the existing row's `Seller ID` against the incoming update's `sellerId`.
    *   **Match:** If the IDs match, we assume the seller hasn't changed. We **preserve** the existing `Seller` field (keeping the human-readable name).
    *   **Mismatch:** If the IDs differ (indicating the Buy Box/Used winner changed), we must update the record. Since we don't have the new name in a lightweight fetch, we fall back to the ID (which is better than showing the *wrong* name). The next "Heavy" update or manual refresh will eventually catch the new name.

### 2. Frontend UI
*   We located the `.truncated` class in `static/global.css`.
*   We removed the `cursor: help;` property. The element now inherits the default cursor (or pointer if clickable), removing the confusing visual cue.

## Verification
*   **Unit Testing:** Created `tests/test_seller_name_logic.py` which mocks the database row and API response to verify that:
    *   Matching IDs -> Name is preserved.
    *   Mismatched IDs -> Name is overwritten with new ID.
    *   Missing Old ID -> Name is overwritten with new ID.
*   **Frontend Verification:** Used a Playwright script (`verification/verify_cursor.py`) to render the dashboard and verify via `window.getComputedStyle` that the cursor on truncated elements is no longer `help`.

## Files Changed
*   `keepa_deals/processing.py`: Logic for `Seller ID` handling.
*   `static/global.css`: Removed `cursor: help`.
*   `tests/test_seller_name_logic.py`: New regression test.