# Dev Log: Session 4 — Hyperlinks + Sort Arrows on Tracking Page

**Date:** 2026-05-25
**Author:** Jules (AI Agent), with post-deployment corrections by Tim + Claude
**Status:** Success (after iteration)

## Overview

Two related UX polish tasks across all three Tracking tabs (Potential Buys, Active Inventory, Sales & Profit):
1. ASIN, SKU, and Order ID values displayed as hyperlinks (opening in new tabs) to their respective Amazon and Seller Central pages.
2. Client-side sortable columns with arrows visually and behaviorally matching the Dashboard.
3. Sticky table headers with shadow effect adapted from the Dashboard for the Tracking page's tab-nav layout.

## Implementation Details

### 1. Hyperlinks

- Added `.tracking-link` CSS class to `static/global.css` matching the existing color `#a3aec0` with hover underline effect.
- Updated `renderPotential()`, `renderActive()`, and `renderSales()` in `templates/tracking.html` to wrap displayed identifiers in `<a>` tags with `target="_blank" rel="noopener noreferrer" class="tracking-link"`.

URL patterns used:
- **ASIN** → `https://www.amazon.com/dp/{ASIN}` (Amazon product detail page)
- **SKU** → `https://sellercentral.amazon.com/myinventory/inventory?fulfilledBy=all&page=1&pageSize=250&searchField=all&searchTerm={SKU}&sort=sales_desc&status=all` (Manage Inventory page pre-filtered to that SKU)
- **Order ID** (Sales & Profit tab only) → `https://sellercentral.amazon.com/orders-v3/order/{ORDER_ID}` (Order detail page)

SKU URL construction is centralized in a `skuSearchUrl()` helper function in the script block to avoid duplication and ensure consistency.

Empty/missing values render as em dashes (—) instead of linked text.

### 2. Sort Arrows and Toggles

- Reused the Dashboard's arrow image assets (`ascending-on.png`, `ascending-off.png`, `descending-on.png`, `descending-off.png`) and toggle pattern.
- Behavior matches Dashboard exactly: separate up/down arrows, no third-click clear state. The table is always sorted either ascending or descending on the selected column.
- Default sort state per tab: most-recent first (matches existing API ordering by `created_at` / `purchase_date` / `sale_date`).
- Injected `<tr class="sort-arrows-row">` below the main table header for all three tracking tabs.
- Implemented robust client-side sorting logic (`sortData`) supporting:
  - String comparison (Title, ASIN, SKU, etc.)
  - Numeric comparison with currency/percentage symbol stripping (`$`, `,`, `%`)
  - Date parsing for date columns
  - Em-dashes treated as null/missing and forced to the bottom regardless of sort direction
- Global state tracking via `sortState` object and cached `currentData` to apply sort on display without refetching from API.
- `event.stopPropagation()` on arrow clicks to prevent triggering parent cell interactions (e.g., editable Buy Cost click-to-edit).

### 3. Sticky Headers with Shadow Effect

- Added `#tracking-shadow-line` and `.tracking-sticky-mask` elements to emulate the Dashboard's scroll behavior where rows appear to scroll "under" the table headers.
- Dynamic scroll trigger uses `getBoundingClientRect()` to measure the active table's position relative to the viewport — shadow appears only when header actually reaches the sticky threshold (134px from top), not on arbitrary scroll distance.
- Z-index ordering in `global.css`: sticky header (`th`) at `180`, sort arrows row (`td`) at `179`, mask and shadow at `178` — ensures mask hides scrolling content behind the header without covering the header or arrows themselves.

## Edge Cases Handled

- **Missing data:** Em dashes render in place of empty/null values; no link tags generated for missing IDs.
- **Sort tie-breakers:** Empty/em-dash values sort to bottom regardless of direction.
- **Interactive cells:** Sort arrows above editable Buy Cost pill do not trigger edit mode (stop propagation).
- **Tab switching:** Each tab maintains independent sort state.

## Post-Deployment Corrections (2026-05-25)

After initial deployment, testing exposed three issues that required follow-up fixes:

### Issue 1: Multiple Jules commits required for sticky shadow behavior
The shadow + sticky header behavior took several iterations to translate correctly from Dashboard to Tracking page. The Dashboard has no tab nav above its table, but Tracking has a tab-nav row that pushes the table header down, breaking simple scroll-position checks. Final fix uses dynamic `getBoundingClientRect()` measurement to detect when the table header actually sticks, rather than relying on a fixed scrollY threshold.

### Issue 2: SKU links missing from initial Jules commit
The initial commit linked only ASINs (already partially linked) and missed SKUs entirely. A follow-up turn with Jules was requested to add SKU links and an Order ID link on the Sales & Profit tab. Order ID linking is a small bonus addition since Amazon order IDs are unique 1:1 with purchases (unlike SKUs, which may cover multiple units).

### Issue 3: SKU URL pattern returned unfiltered Manage Inventory page
The originally specified URL pattern (`/inventory?searchType=sku&searchValue={SKU}`) did not honor query parameters on Amazon's current Seller Central. Clicking a SKU link landed on the unfiltered Manage All Inventory page instead of filtering to the specific SKU.

**Investigation:** Tim performed a manual SKU search in Seller Central and captured the working URL. Amazon's current Manage Inventory page uses:
- Path: `/myinventory/inventory` (not just `/inventory`)
- Query params: `searchTerm` (not `searchValue`), plus `searchField=all`, `fulfilledBy=all`, `page=1`, `pageSize=250`, `sort=sales_desc`, `status=all`

**Fix:** Replaced the URL pattern across both `renderSales()` and `renderActive()`. Centralized into a `skuSearchUrl(sku)` helper function at the top of the script block so future SKU links use the same correct pattern. SKU values are URL-encoded with `encodeURIComponent()` for safety.

### Issue 4: Inconsistent ASIN link styling
The pre-existing ASIN link on Potential Buys used inline `style="color: #a3aec0;"` instead of the new `.tracking-link` class. While functionally equivalent, this created two patterns for the same visual outcome — bad for maintainability.

**Fix:** Updated the Potential Buys ASIN link to use the `.tracking-link` class consistent with all other ASIN/SKU links across the page.

## Results

All three Tracking tabs now feature:
- Functional hyperlinks on ASIN, SKU, and (Sales & Profit) Order ID
- Client-side sortable columns matching Dashboard behavior and visual style
- Sticky headers with shadow effect mirroring the Dashboard experience

All link patterns verified working against Amazon and Seller Central. Tests passed.

## Known Limitations (deferred to future cards)

- **Client-side sort scales with table size.** Current Keepa API tier 1 caps the dashboard around 350 deals; Tracking tables are smaller. When Keepa tier increases or user inventory/sales history grows, server-side sort/pagination will be needed. Captured as `[P3] Server-side sort and pagination for Tracking page tables`.
- **Broken diagnostic tool surfaced during planning.** The rejection-rate diagnostic fails with `ModuleNotFoundError: No module named 'keepa_deals'`. Not addressed in this session; captured as `[P2] Fix broken rejection rate diagnostic`.