bash - sftp sync and backup -- 2

I need script in bash: 1) connect to sftp to remote server 2) found all newer files on remote files without prefix (file) than local with prefix (file-somting) - compare by date 3) check that file not in uploading state on remote (files will be less than 1mb) 4) download newer files wihout prefix (file) 5) if remote file was download(from 3) ), local files with prefix (file-something) backup with prefix and date (file-something-date) 6) call separately some script for every new file (example: "cat file1" "cat file2") 7) after script executing rename newest file to prefix name than local with prefix (file-somting)