Facebook Group Auto Comment Crawler

I need a small application (script or lightweight desktop tool) that can quietly monitor a set of Facebook groups, spot question-based posts that match keywords I define, and drop a friendly, casual reply that directs people to my website... (Budget: £250 - £750 GBP, Jobs: API Development, Automation, Desktop Application, JavaScript, Node.js, PHP, Python, Selenium, Software Architecture, Web Scraping)