Call centre solution

We are looking customised multi-tenant open source call centre VOIP solution, with an android and IoS app for calling agents. We should be able to appoint resellers, white label it for resellers, we should be able to sell b2b call centre solutions to clients in various industries. It should have the following features. All modes of dialing (Preview, manual and predictive mode) Call monitoring Call recording Dashboard DID management Graphical reports Multi-level IVRS Productivity Sale Graph Real-time call status Standard Call features Standard reports and other range of reports Voicemail All basic features Inbound number Black Listing Email & SMS Module Internal Chat Module Skill based Routing with Agent Ranking Sticky Agent You may use any or many open source softwares to get these features, like Asterisk Fusion Pbx, ASTPP, FreePbx, free switch telephony, webrtc, a2billing, vicidial, magnus billing etc. The system has to be robust scalable and capable to handle growth