Develop streaming website - Audio

1) Develop a website that can store and play audio files (thousands of them) 2) The audio files should be sorted under various categories and sub-categories e.g. History, Geography, etc 3) The user have to sign up to listen to the audio files. Should have 2 types of users: Administrator and Normal User 4) The users should be able to listen to the audio category of their choice e.g. if user select History, the History audio files will be played continuously at random until user click stop (might be few hours or whole day). Therefore good streaming is required. Ideas are welcome on how to provide uninterruptible streaming 5) User can also select a mix of categories e.g. History, Science and Geography and the files from selected categories will be played at random as the above Item (4) 6) User (Administrator) can upload their own audio files and set them as Compulsory files to be played e.g.: Audio1 > Audio2 > CompulsoryFile1 > Audio3 > Audio4 > Compulsory File1 > Audio5 ... and so on. 7) The audio category selected by user can be defined by date e.g. History to be played 1 June - 30 June; Geography 1 July - 31 July, etc 8) Administrator can monitor which Users are online 9) Website should be user-friendly for both users and web owner