A quick little command line tool to copy a left/right page count to your clipboard. Maybe helpful for book design.

pagecount-cheatsheet.py

"""
    Book page cheat sheet!
   
    Alternate left/right alongside number for a given page count.

    Example:

        1 Right
        2 Left
        3 Right
        4 Left
        5 Right
        6 Left
        7 Right
        # etc

    (Assumes you are on macOS. Might still work on Windows or Linux, etc, but this hasn’t been tested.)

    USAGE:

    1. Download this file
    2. Select the file in Finder and then hit Command-Option-C to copy its path
    2. Open the Terminal app
    3. Paste the file path after "python3" in the terminal, like this:

       python3 path_to_script/pagecount-cheatsheet.py

    4. It will ask for a page count. Enter that number.

    The cheat sheet will be copied to your clipboard! 
    Paste it into a note or whatever.

    Note: If you have never before installed Python, macOS will prompt you to do so. Do that, restart Terminal, and try again.

"""

import math
import subprocess


def askPageCount():
    try:
        # prompt user for page count
        total_pagecount = int(input("🤖 Enter a page count: "))
    except:
        # if user doesn't enter page count number, just use 32
        total_pagecount = 32

    return total_pagecount


def checkIfDivisibleBy16(total_pagecount):
    # check if the pagecount is divisible by 16, and let the user know if not
    if total_pagecount % 16 != 0:
        lowerPossibility = math.floor(total_pagecount / 16) * 16
        upperPossibility = math.ceil(total_pagecount / 16) * 16
        print(f"⚠️  Psst: {total_pagecount} isn’t divisible by 16.")
        print(f"⚠️  It won’t make even signatures.")
        print(f"⚠️  Did you mean {lowerPossibility} or {upperPossibility}?")


def writePageCount(total_pagecount):

    cheatSheet = []

    for count in range(total_pagecount):
        page = count + 1

        # if page is odd
        if page % 2 == 1:
            cheatSheet.append(f"{page} Right")
        # if page is even
        else:
            cheatSheet.append(f"{page} Left")

    outputText = "\n".join(cheatSheet)

    return outputText


def write_to_clipboard(output):
    process = subprocess.Popen(
        'pbcopy', env={'LANG': 'en_US.UTF-8'}, stdin=subprocess.PIPE)
    process.communicate(output.encode('utf-8'))


def main():

    print() # print blank line

    # ask user for a pagecount
    total_pagecount =  askPageCount()
    
    print() # print blank line

    # check if the pagecount is divisible by 16, and let the user know if not
    checkIfDivisibleBy16(total_pagecount)

    print() # print blank line

    # create alternating number rows for cheat sheet
    outputText = writePageCount(total_pagecount)

    # write result to clipboard for easy use!
    write_to_clipboard(outputText)

    print(f"🤖 Cheat sheet copied to clipboard!")
    print(f"🤖 Go paste it into a note or whatever.")

main()