Call Center Click2Dial & Statistics

We need to build a CRM system for click2dial call center. There should be about 20-30 users with 2-3 levels of management. Contacts should be able to import with CSV based on criteria of groups ex. language, departments etc. Agents(users) should be able to be assigned to specific groups where based on that the contacts will be displayed so they can call them. If a contact is opened( clicked to dial) than that contact should be locked so no one else can open for calling. Call center is using asterisk based Elastix for the moment so all inbound calls should be imported automatically or with interaction with an agents into this CRM so that we have a history of all outgoing and incoming calls history of the specific number(customer). -After this level one privilege than if an agents reach a customer the lead should be finished and if it has a specific status it should be moved to another level 2 of managers so that they know for further processing. An important issue is that each contact should have a field on how many times this number is called(opened) and than a history of them(based on time and agent name) CRM should have a reports page for reporting statistics of contacts called, contacts reached, outgoing and incoming calls etc. Waiting for a serious bidder which has experience and previous work on this field.