// ==UserScript==
// @name         Background Script - SteamGifts Giveaways
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Background script for retrieving and counting table column headings from SteamGifts Giveaways page
// @author       Your Name
// @match        https://www.steamgifts.com/giveaways/entered*
// ==/UserScript==

console.log('Background script loaded.');

// Create the button
let button = document.createElement('button');
button.textContent = 'Retrieve Column Headings';
button.style.position = 'fixed';
button.style.left = '10px';
button.style.bottom = '10px';
button.style.zIndex = '9999';
button.style.backgroundColor = '#4CAF50'; // Green background color
button.style.color = 'white'; // White text color
button.style.border = 'none'; // No border
button.style.padding = '10px 20px'; // Padding around the text
button.style.fontWeight = 'bold'; // Bold text
button.style.cursor = 'pointer'; // Pointer cursor on hover
document.body.appendChild(button);

let resultDisplay = document.createElement('div');
resultDisplay.style.position = 'fixed';
resultDisplay.style.left = '10px';
resultDisplay.style.bottom = '50px';
resultDisplay.style.zIndex = '9999';
resultDisplay.style.backgroundColor = 'white';
resultDisplay.style.padding = '10px';
resultDisplay.style.border = '1px solid #ccc';
resultDisplay.style.overflow = 'auto';
resultDisplay.style.maxWidth = '400px';
resultDisplay.style.maxHeight = '550px';
document.body.appendChild(resultDisplay);

// Object to store the count of each table column heading across all pages
let headingsCount = {};

// Function to retrieve column headings from a page
async function retrieveColumnHeadings(page, endPage) {
    console.log(`Retrieving column headings for page ${page}.`);
    if (page > endPage) {
        console.log('All pages processed. Sending result to content script.');
        // If all pages are processed, send the final result to the content script
        const sortedHeadings = Object.entries(headingsCount)
            .sort(([, countA], [, countB]) => countB - countA) // Sort entries by count in descending order
            .map(([heading, count]) => `${heading.replaceAll('<','&lt;').replaceAll('>','&gt;')} (Repeated ${count} times)<br>`) // Add line break after each entry
            .join(''); // Join entries with line breaks
        resultDisplay.innerHTML = sortedHeadings;
        button.disabled = false;
        return;
    }

    let resp = await fetch(`https://www.steamgifts.com/giveaways/entered/search?page=${page}&sort=all`, {method: 'GET'})
    console.log(`Received response for page ${page}.`);
    resultDisplay.textContent = `Processing page ${page} of ${endPage}`
    const parser = new DOMParser();
    const doc = parser.parseFromString(await resp.text(), 'text/html');
    const columnHeadings = doc.querySelectorAll('.table__column__heading');
    columnHeadings.forEach(heading => {
      let text = '';
      const children = heading.childNodes;
      children.forEach(child => {
        if (child.nodeType === Node.TEXT_NODE) {
          text += child.textContent.trim();
        }
      });
      headingsCount[text] = (headingsCount[text] || 0) + 1;
    });
    // Continue retrieving column headings from the next page after a delay
    setTimeout(() => {
      retrieveColumnHeadings(page + 1, endPage, resultDisplay);
    }, 1000); // 1 second delay
}

// Click event handler for the button
button.addEventListener('click', async () => {
    headingsCount = {};
    console.log('Button clicked. Initiating data retrieval.');
    const endPage = parseInt(prompt('Enter the end page number:'), 10);
    if (isNaN(endPage) || endPage < 1) {
        alert('Invalid end page number. Please enter a valid number.');
        return;
    }
    resultDisplay.textContent = "Processing..."
    button.disabled = true; // Disable the button to prevent multiple clicks
    retrieveColumnHeadings(1, endPage);
});