Round Cube enhancement with OwnCloud - repost

We have a Round Cube Webmail based on postfix, Dovecot, Amavis and Roundcube. The Project has three aspects: [login to view URL] features integration to Roundcube: We would like to add Owncloud functionality to the roundcube console. The Owncloud link on Roundcube should have single signon with Roundcube user and domain. The Owncloud link on Roundcube should have support for Files and Folder, Music Files with web player, Video Files with web player, Photo Files/Albums, Notes, PDF viewers, ODF viewers, Documents Viewers and creation/edition of .doc/.xls/.ppt/docx/xlsx/pptx/odt/pdf natively in the browser screen. The Owncloud link should have support and integration with Roundcube to unload or download the email attachments directly from web brower itself from the owncloud storage on the cloud. 2. We would want a billing system for our roundcube and owncloud from the cloud: We were using ISPconfig3 but find the below two flaws there a. LDAP Directory support missing with single LDAP instance covering all the domains. b. Advanced reporting to Resellers, Customers and Admin with Reports emailing on time or event trigger features missing. 3. The Roundcube interface has a chat option. I seek help in enhancing the same to use the xmpp based chat integrated with the LDAP above for text chat, text chat rooms+ integrate with asterisk server on the cloud setup to give complete SIP Based audio telephony, Audio Conferencing, Voice mail, Voice mail to Email, Video Chat, Video Conferencing, Integration with third party MCU (Polycom/Cisco) for Video Conferencing/chat, Web meetings with desktop sharing, presentations, whiteboarding, (Similar to webex) to be integrated as a tab in roundcube. It is critical to have domain based logical partitioning on the server to hold inter domain calls and dial plans. All the above work must be done with preplanned documentation on architecture and later submitted with the code segregated and documentation for further enhancements and administration.