Develop Help Desk System in PHP Framework

Need to develop a fully responsive website with a Help Desk system in a good PHP Framework like Laravel It can take help from 3rd party applications, but should not incur any additional recurring expenditure. The important features needed include: 1. Support Ticketing system: -- Three levels of supervisory access (Staff, Supervisor, Admin) to view the replies and whether replied (red flags if not replied on time) and access permissions can be specified -- Users can send a mail and the tickets will be created -- Users can get replies by mail as well -- Unlimited departments -- Unlimited users -- Unlimited tickets -- Assign priority to tickets -- Support team members can discuss with each other -- Support team members can convert a reply to an FAQ -- HTML Mail if required -- Staff can add documents / media/ canned responses to the reply 2. Downloads -- Logged in Users can download files from Downloads section -- Admin / Supervisor should be able to add the files from the back end -- Prioritise / search the files with keywords 3. FAQ -- Add FAQs as per category --> Question and Answer -- Admin / Supervisor / Staff can convert a support ticket Q and A into an FAQ 4. Knowledgebase -- Articles categorised in 3 tier directory . Category --> Subcategory --> Article 4. Online Chat with user (This can be integrated or kept separately in the proposal ) The code should be available on the site and if the staff are online, should show online status, otherwise offline status or away status if the staff is idle for more than 15 minutes Offline message should generate mail to create support ticket from the mail already collected Staff should be able to login to answer queries Any more interesting features are welcome