runshow.py

"""
Show Runner script for the PiLit holiday lighting controller
Author: Tim Poulsen, @skypanther
License: MIT

This script runs on your Raspberry Pi, reads in a show.json
file, and turns on/off the relays to perform your show.

Setup:

1. Make sure you have gpiozero installed on your Pi with:

> sudo apt-get update
> sudo apt-get install python3-gpiozero python-gpiozero

2. Update the gpio_pins list below with the pin numbers you're
using on your Pi. If you're using less than 16 pins, simply
delete any extra numbers from the sample line below.

   NOTE: You must use the BCM (Broadcom) numbers for the pins
   and NOT their physical pin numbers!

3. Run it (manually or from cron) with a command in the form:

> python3 runshow.py show.json HH:MM

  where show.json is the name of your show file (in same
  directory as this file) and HH:MM is the hours and minutes
  of when to end the show.

For example:

> python3 runshow.py show.json 22:30

Runs the show.json show till 10:30 PM tonight.

"""

import sys
from datetime import datetime
from time import sleep
import json
import os.path
from gpiozero import LED

# CONFIGURE THESE VARIABLES TO SUIT YOUR ACTUAL SETUP
# USE BCM (BROADCOM) NOT PHYSICAL PIN NUMBERS
# don't use GPIO 14 / pin 8 on a Pi B+ as it's the "hard drive light" pin
gpio_pins = [2, 3, 4, 7, 15, 17, 18, 27, 22, 23, 24, 10, 9, 25, 11, 8]
# board_pins 3, 5, 7, 26, 10, 11, 12, 13, 15, 16, 18, 19, 21, 22, 23, 24


# DON'T CHANGE THESE VARIABLES
midnight = datetime.today().replace(hour=23, minute=59, second=59, microsecond=999999)
args = sys.argv[1:]
pins = []


def main():
    if len(args) == 0:
        # prompt for show name, duration
        show_name = input("Enter the show name: ")
        the_time = input("When should the show end? (time as HH:MM):")
        if "." not in show_name:
            show_name += ".json"
        if the_time == "":
            end_time = midnight
        else:
            end_time = format_end_time(the_time)
    elif len(args) == 1 and args[0] == "off":
        # turn all lights off then exit
        all_off()
        exit()
    elif len(args) == 1 and args[0] == "on":
        # turn all lights on then exit
        all_on()
        exit()
    elif len(args) == 1:
        show_name = args[0]
        end_time = midnight
        if "." not in show_name:
            show_name += ".json"
    else:
        show_name = args[0]
        end_time = format_end_time(args[1])
        if "." not in show_name:
            show_name += ".json"
    if not os.path.isfile(show_name):
        print("No show file by that name")
        exit()
    run_show(show_name, end_time)


def run_show(show_name, end_time):
    # Runs the actual show
    with open(show_name) as json_file:
        show_file = json.load(json_file)
    if "show" not in show_file:
        print("Bad show file")
        exit()
    show = show_file["show"]
    delay = show_file["interval"] if "interval" in show_file else 500
    delay = delay / 1000.0
    now = datetime.now()
    while now < end_time:
        for channel in show:
            control_channel(channel)
            sleep(delay)
        now = datetime.now()


def format_end_time(the_time):
    # Formats an HH:MM time string into an actual datetime
    input_time = the_time.split(":")
    end_time = datetime.today().replace(
        hour=int(input_time[0]), minute=int(input_time[1])
    )
    return end_time


def all_on():
    # Turns on all relays
    for pin in pins:
        pin.on()


def all_off():
    # Turns off all relays
    for pin in pins:
        pin.off()


def control_channel(channel):
    """
    Turns on or off the relays for a specific channel in the show file
    """
    if len(channel) != len(pins):
        msg = """
Error:
You must make sure the number of items in the gpio_pins
list in runshow.py is the same as each channel in the show
list defined in your show.json file
"""
        sys.exit(msg)
    for index, relay_state in enumerate(channel):
        if relay_state == 1:
            pins[index].off()
        else:
            pins[index].on()


def setup_pins():
    """
    Creates the LED instances for each of the pins to which
    you have relays connected and stores them in the pins list
    """
    for pin_number in gpio_pins:
        pins.append(LED(pin_number))


if __name__ == "__main__":
    setup_pins()
    main()