Bourne Shell Scripting Assistance

#! /bin/sh
# Option 2
# Get date from user
echo "Please enter day, month and year of event:"
read date

if [ $# -eq 3 ]
then
    if [ $3 -lt date '+%Y' ]
    then
        echo Invalid year entered.
    else
        if [ $2 -le `date '+%m'`]
        then
            echo Invalid date entered.
        else
            if [ $1 -le `date '+%d'` ]
            then
                echo Invalid month entered.
            else
                # Get hour, minute and length from user
                echo "Please enter hour, minute and length of event:"
                read time

                # Check that hour is valid.
                if [ $1 -lt 0 -a -gt 23 ]
                then
                    echo Invalid hour entered. Must be between 0 and 23 inclusive.
                else
                    if [ $2 -lt 0 -o -gt 59 ]
                    then
                        echo Invalid minute entered. Must be between 0 and 59 inclusive.
                    else
                        # Get title from user
                        echo "Please enter a title for your event:"
                        read title
                    fi
                fi
            fi
        fi
    fi
else
    echo Invalid number of arguments entered.
fi