This script automatically captures and logs the positional changes of Adobe's San Jose Semaphore discs in real-time, stops after reaching a predefined limit, and exports the logged data for further analysis.

semaphore-scraper.js

/*
    Adobe Semaphore Data Capture
    Author: @jadeallencook
    Date: May 13, 2023

    This script captures the position sequences of the semaphore wheels from the Adobe Semaphore public art installation.
    
    The script queries the semaphore's website, maps the transform styles of the wheel elements to their positions,
    and stores the sequences of positions in an array. The script logs every captured sequence, and logs the progress
    every 10 sequences. Once the script has captured a predetermined maximum number of sequences, it logs the entire
    array of sequences and stops the capturing process.

    |: 1
    /: 2
    -: 3
    \: 4

    https://www.adobe.com/about-adobe/visit-us/sj-semaphore.html
 */

// Mapping of matrix transforms to wheel positions
const positions = {
    'matrix(-1, 0, 0, -1, 0, 0)': 1,
    'matrix(0.707107, 0.707107, -0.707107, 0.707107, 0, 0)': 2,
    'matrix(0, -1, 1, 0, 0, 0)': 3,
    'matrix(0.707107, -0.707107, 0.707107, 0.707107, 0, 0)': 4,
    'matrix(1, 0, 0, 1, 0, 0)': 1,
    'matrix(-0.707107, -0.707107, 0.707107, -0.707107, 0, 0)': 2,
    'matrix(0, 1, -1, 0, 0, 0)': 3,
    'matrix(-0.707107, 0.707107, -0.707107, -0.707107, 0, 0)': 4
}

// Query the container of the semaphore wheels
const container = document.querySelector('.css-1q7ngnn');

// Get all the wheel elements
const wheels = [...container.childNodes];

// Array to store the sequences of wheel positions
const stream = [];

// Counter for the number of captured sequences
let numberOfSequences = 0;

// Maximum number of sequences to capture
let maxNumberOfSequences = 3000;

// Function to get the position of a wheel
const getWheelPosition = (wheel) => {
    const string = window.getComputedStyle(wheel).transform;
    return positions[string] || 0;
}

// Function to update the stream with a new sequence of wheel positions
const updateStream = (data) => {

    // If the sequence is the same as the last sequence in the stream, do nothing
    if (JSON.stringify(data) === JSON.stringify(stream.at(-1) || [])) {
        return;
    }

    // Otherwise, push the sequence to the stream and increment the counter
    stream.push(data);
    numberOfSequences++;
    console.log(`CAPTURED: [${data.join(', ')}]`);

    // Every 10 sequences, log the progress
    if (!(numberOfSequences % 10)) {
        console.log(`PROGRESS: ${numberOfSequences}/${maxNumberOfSequences}`);
    }

    // If the counter reaches the maximum, log the entire stream and stop the process
    if (numberOfSequences === maxNumberOfSequences) {
        console.log(`EXPORT: ${JSON.stringify(stream)}`);
        clearInterval(process);
    }
}

// Start a process to capture wheel positions every 500 ms
const process = setInterval(() => {

    // Map the wheels to their positions
    const data = wheels.map(wheel => getWheelPosition(wheel));

    // If no wheel position is 0 (not recognized), update the stream with the new sequence
    if (!data.includes(0)) {
        updateStream(data);
    }

}, 500);