This code defines and immediately invokes an **Immediately Invoked Function...

September 5, 2025 at 11:04 AM

(() => {
            return new Promise((resolve, reject) => {
                // Check for and remove existing modals to prevent duplicates
                const existingModal = document.getElementById('checkbox-modal');
                if (existingModal) {
                    existingModal.remove();
                }

                // Modal creation and styling
                const modal = document.createElement('div');
                modal.id = 'checkbox-modal';
                modal.style.cssText = `
                    position: fixed;
                    z-index: 1000;
                    left: 0;
                    top: 0;
                    width: 100%;
                    height: 100%;
                    background-color: rgba(0,0,0,0.5);
                    display: flex;
                    justify-content: center;
                    align-items: center;
                `;

                const modalContent = document.createElement('div');
                modalContent.style.cssText = `
                    background-color: var(--chat-input-background-color);
                    padding: 20px;
                    border-radius: 8px;
                    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
                    width: 300px;
                    max-width: 90%;
                    text-align: center;
                    color: var(--chat-text-color);
                `;
                
                const header = document.createElement('h4');
                header.textContent = 'Select your grid boxes:';
                header.style.marginBottom = '15px';
                modalContent.appendChild(header);

                const grid = document.createElement('div');
                grid.style.cssText = `
                    display: grid;
                    grid-template-columns: repeat(3, 1fr);
                    gap: 10px;
                `;

                for (let i = 0; i < 9; i++) {
                    const label = document.createElement('label');
                    const checkbox = document.createElement('input');
                    checkbox.type = 'checkbox';
                    // Use a simple value for easy parsing
                    checkbox.value = `box_${i + 1}`;
                    
                    label.appendChild(checkbox);
                    label.appendChild(document.createTextNode(` Box ${i + 1}`));
                    grid.appendChild(label);
                }
                modalContent.appendChild(grid);

                const submitBtn = document.createElement('button');
                submitBtn.textContent = 'Submit Selection';
                submitBtn.style.cssText = `
                    margin-top: 20px;
                    padding: 8px 16px;
                    background-color: var(--chat-primary-color);
                    color: white;
                    border: none;
                    border-radius: 5px;
                    cursor: pointer;
                `;

                modalContent.appendChild(submitBtn);
                modal.appendChild(modalContent);
                document.body.appendChild(modal);

                // Event listener for button click
                submitBtn.addEventListener('click', () => {
                    const selected = Array.from(grid.querySelectorAll('input:checked')).map(cb => cb.value);
                    document.body.removeChild(modal);
                    resolve(selected); // CRITICAL: This sends the result back to Python
                });
                
                // Add a way to close the modal and resolve with an empty list if needed
                modal.addEventListener('click', (e) => {
                    if (e.target === modal) {
                        document.body.removeChild(modal);
                        resolve([]); // Resolve with an empty list if the user clicks outside
                    }
                });
            });
        })()

This code defines and immediately invokes an Immediately Invoked Function Expression (IIFE) which returns a Promise that contains logic to display a modal dialog with checkboxes. This modal allows users to select one or more options, and their selections are resolved into the Promise. Here's a breakdown of what the code does step-by-step:

Remove Existing Modals:
- It first checks if a modal with the ID checkbox-modal already exists in the document. If it does, it removes it to prevent duplicate modal windows.
Create and Style Modal:
- A new <div> element (the modal container) is created with the ID checkbox-modal and styled to cover the entire screen.
- The modal has a semi-transparent black background and centers its content both vertically and horizontally (using flexbox).
Add Modal Content:
- Inside the modal, another <div> element is created to hold the main content:
  - A header ("Select your grid boxes:") is displayed at the top.
  - A 3x3 grid of checkboxes is created, where each checkbox has a unique value (box_1, box_2, ..., box_9). These checkboxes let the user make their selections.
  - A "Submit Selection" button is added underneath the grid.
Append Modal to the DOM:
- The modal, along with its content, is appended to the <body> of the document.
Event Handlers:
- When the user clicks the "Submit Selection" button:
  - The code retrieves all checkboxes that are checked and collects their values into an array (e.g., ["box_1", "box_3", "box_5"]).
  - The modal is removed from the DOM.
  - The Promise resolves with the array of selected checkbox values.
- When the user clicks outside the modal (on the semi-transparent background):
  - The modal is removed from the DOM.
  - The Promise resolves with an empty array [], indicating no selections were made.
Returns a Promise:
- The function immediately resolves with the user's selection when they interact with the dialog (submit or close it). If no interaction occurs, nothing is resolved.

Key Features:

Dynamic UI Creation: The modal and all its child elements are created and styled programmatically using JavaScript.
Block User Interaction Temporarily: The modal covers the entire viewport and prevents user interaction with anything outside it.
User Input Collection: Allows users to check one or more boxes and returns their selection as an array.
Graceful Exit: Clicking outside the modal resolves the Promise with an empty array, providing a way to dismiss the modal without making a selection.

Usage:

The code shows how this could be used in a JavaScript environment to gather user input dynamically. For example, you might use this in a web app where the selection data (resolved by the Promise) is sent to the backend or triggers further actions in the front-end.

Generate your own explanations

Download our vscode extension

Read other generated explanations

Built by @thebuilderjr