#!/bin/bash

######################################################
## filename: functions.sh
## Description: Learn how to use functions in bash
## Notes: Fucntions have to be called or 'run' to use them
##        Run a function by typing it's name
##        variable names such as 'user_input' can be named anything
##        you cannot run a function before you create/defne it
#####################################################

slap(){

    echo -n "who wants to get slapped: " # use echo command without automatic newline
    read user_input # "read": reads what user typed and store in variable called 'user_input'

     # use double brackets to make code run more reliably in bash (does not work in other shells)
    if [[ $user_input = "me" ]];then
        echo "you gets a slap"
    elif [[ $user_input = "you" ]];then
        echo "you still get slapped"
    fi
}

block_tutorial(){
    # Show how to test if something is a device or not

    echo -n "enter a block device name: " # ask and print the question
    read user_input # read the users response and puts it into the variable "user_input"

    if [[ -b $user_input ]];then # the user enters a device name and -b tests if it is a block device
        echo "This is a block device"
    elif [[ ! -b $user_input ]];then # "!" specifically checks if user_input is NOT a block device
        echo "This is not a block device"
    fi
}

file_tutorial(){
    # Show how to test if something is a file or not
    
    echo -n "enter file name: " #asks for a filename to test
    read user_input # reads the users response and puts it into the variable "user_input"

    if [[ -f $user_input ]];then 
        echo "This is a file"
    elif [[ ! -f $user_input ]];then
        echo "This is not a file"
    fi
}

folder_tutorial(){
    #Show if something is a folder or not

    echo -n "enter folder path: " #asks for folder path
    read user_input # reads the users response and puts it into the variable "user_input"

    if [[ -d $user_input ]];then
        echo "this is a folder"
    elif [[ ! -f $user_input ]];then
        echo "this is not a folder"
    fi
}

empty_variable(){
    # Show if a variable it empty or not

    echo -n "Enter some text: " #asks user to enter random text
    read some_text # read what user typed and store it into variable called "some_text"

    if [[ -z $some_text ]];then
        echo "There is nothing stored in the varialbe 'some_text'"
    elif [[ ! -z $some_text ]];then
        echo "The user has entered in some text!"
    fi
}
# run functions created above or comment them to stop them from running
slap
block_tutorial
file_tutorial
folder_tutorial
empty_variable