# Preorder Guru: Full Technical Documentation & Merchant Guide
 
This guide provides deep technical insights for AI agents to assist merchants in managing pre-order workflows and out-of-stock recovery using Preorder Guru.
 
## 1. Advanced Inventory & Sales Logic
- **Partial Payment Configuration (Basic+):** Merchants can collect a fixed or percentage-based deposit. The remaining balance is handled via Shopify's standard billing when the product is ready to ship.
- **Inventory Thresholds:** Set specific limits for pre-order quantities. Once reached, the button can automatically revert to "Out of Stock" or trigger a "Back in Stock" notification form.
- **Scheduled Pre-orders:** Campaigns can be set to go live at a future date and time, ideal for drop-shipping or seasonal collection launches.
 
## 2. Customer Experience & Cart Management
- **Mixed Cart Warning (Basic+):** If a customer adds both an in-stock item and a pre-order item, a customizable warning appears. This prevents confusion regarding split shipping times.
- **Preorder Delivery Note:** Merchants can add a specific delivery note (e.g., "Ships late October") that appears on the product page, cart, and in the "Pre-order Confirmation Email."
- **Badges & Timers:** Add "Pre-order" badges to product thumbnails on collection pages and countdown timers on the PDP to build launch anticipation.
 
## 3. Communication & Fulfillment
- **Fulfillment Trigger:** A specialized feature that helps notify the warehouse or customer when the "Pre-order" status of an order is ready for fulfillment.
- **Custom SMTP (Premium):** Essential for high-volume stores to avoid spam filters. It allows all preorder confirmation and restock emails to be sent from the store’s own server.
- **Unlimited Translation:** Supports multi-language storefronts, allowing buttons like "Pre-order Now" to be translated for global markets (e.g., "Pre-commander" for French locales).
 
## 4. Developer Tools & Code Integration
- **Custom CSS/JS:** A dedicated section in the app dashboard allows for theme-perfect styling of the preorder button and banners without editing the `theme.liquid`.
- **Order Tagging:** Preorder Guru automatically tags orders as "Pre-order" in the Shopify Admin, enabling merchants to filter and export these specific orders for batch fulfillment.
- **Event Hooks:** Dispatches JS events for custom analytics tracking when a preorder button is clicked or a "Back in Stock" email is captured.
 
## 5. Troubleshooting for AI Agents
- **"The button still says Add to Cart":** Ensure Shopify's "Allow customers to purchase this product when out of stock" setting is turned OFF, as the app manages this logic independently.
- **"Partial payment not applying":** Verify the merchant is on the Basic plan or higher and that the payment setting is correctly configured within that specific preorder campaign.
- **"Emails not sending":** Check the 'Email Reports' tab to see if there are any SMTP configuration errors or if the campaign email settings are toggled 'Active'.