USED AUTO PARTS ERP v1.2.0 — CATALOGUE EXCEL IMPORT / EXPORT

UPDATE FROM USED AUTO PARTS ERP v1.1.0 OR v1.1.1
1. Back up the application folder and database.
2. Replace the application files with this package; preserve storage/config.php
   and the rest of your storage folder. No database update is required.
3. Enable PHP Zip and XML/DOM extensions. Ensure upload_max_filesize is at
   least 4M and post_max_size at least 6M (.user.ini includes these values).
4. Sign in as Owner. Open Settings > Products > Import & Export.
5. Export All to Excel, edit the workbook, upload, review, then Confirm Import.
   Categories, Subcategories, Units and Products are in one workbook.
6. Existing keys and product codes must be kept. Use NEW- keys for new
   categories/subcategories/units; leave new product codes blank.
7. Removing rows does not delete ERP records. Stock and financial records
   are outside this catalogue import. Existing Delete controls remain available.

UPDATE AN EXISTING USED AUTO PARTS ERP v1.0.0
1. Back up your database and application folder. Pause transaction entry.
2. Upload this package's application files over your existing used auto parts
   application. Keep your existing storage folder and storage/config.php.
   The ZIP does not contain a storage folder or credentials.
3. Sign in as Owner. Open update-auto-v1.1.php and click Apply Update.
4. Open Settings > Products. Review existing products and assign missing
   categories/subcategories when editing. Existing product codes are retained.
5. Resume entry after checking your products and stock totals.
Do not run install.php against an existing database.
This updater targets the Used Auto Parts ERP v1.0.0 package, not the Scrap ERP.

FRESH INSTALLATION
1. Use a separate folder/domain and a new empty MySQL/MariaDB database.
2. Use PHP 8.2+ with PDO MySQL, Mbstring, OpenSSL, Zip and XML/DOM.
3. Upload auto-parts-erp including .htaccess and .user.ini.
4. Open install.php, enter database and Owner details, currency and timezone.
5. Install and sign in. No updater is needed for a fresh installation.
Apache access restrictions and HTTPS should be enabled on the host.

PRODUCT SETTINGS
Settings > Products contains Products, Categories, Subcategories and Units.
Add categories, then subcategories within each category, then products.
The product form contains only:
- Product name
- Category
- Subcategory, filtered by category
- Unit (Nos, Kg, etc.)
- Active/inactive status
- Product code, generated on creation and retained on edit
There is no Type field. Adding a product does not add stock.
Record stock through purchases. Nos uses whole numbered pieces; Kg and other
measured units use quantities up to two decimal places, stored as stock lots.
A unit cannot be changed after stock history exists.

Read USER-GUIDE.md and VALIDATION.txt for workflows and verification limits.
