Multi-API Flight Booking Integration

I already run a PHP-based flight engine that can search, book and take payments. I now want to fold in another XML flight source (possibly two or three in the future) so a single search form queries every connected supplier and shows combined results side-by-side.

Your job is to:
• Connect the new XML API to the existing codebase, map its parameters and responses, and merge the returned itineraries with the ones we already display.
• Extend the current booking-and-payment flow so customers can complete reservations on the new supplier without noticing any difference.
• Build a dedicated back-office area for this integration. It must recognise three roles—Admin, Agent and Customer support—with proper permissions. From there I need to view PNR details, capture or refund payments, and issue e-tickets generated by the new API.

The existing platform is clean PHP (no framework lock-in), MySQL and jQuery, so experience with raw PHP, XML parsing, and flight GDS/OTA standards is essential. Keep the UX consistent with what we already have; I’ll provide you with current UI files and endpoint docs as soon as we start.

Acceptance is simple: live searches must pull fares from both our original source and the new XML feed, bookings must settle correctly, and tickets must appear in the admin panel under the right user role. If you’ve merged multi-supplier flight data before, I’d like to see it.