some systems (depends on ur mb and bios) may allow you to schedule an autostart. if it's not available, check to see if wol is supported on ur mb. either one could be used to wake your pc up and execute the scheduled task. wol may need another pc though.
if autostart is not possible, instead of shutting ur pc down. put it in hibernate state. schedule a task to wake ur pc up and execute the task. find more details in help or on google.
the upload part can be programmed by any methods, a batch file, shell , or even a binary executable.