Adds a button on Amazon product pages to compare prices on farmazon.app
// ==UserScript==
// @name Farmazon Amazon Button
// @namespace https://farmazon.app/
// @version 1.0.2
// @description Adds a button on Amazon product pages to compare prices on farmazon.app
// @author farmazon.app
// @match https://amazon.com/*
// @match https://amazon.co.uk/*
// @match https://amazon.de/*
// @match https://amazon.fr/*
// @match https://amazon.it/*
// @match https://amazon.es/*
// @match https://amazon.ca/*
// @match https://amazon.com.mx/*
// @match https://amazon.com.br/*
// @match https://amazon.in/*
// @match https://amazon.cn/*
// @match https://amazon.co.jp/*
// @match https://amazon.com.au/*
// @match https://amazon.nl/*
// @match https://amazon.se/*
// @match https://amazon.pl/*
// @match https://amazon.sg/*
// @match https://amazon.com.tr/*
// @match https://amazon.sa/*
// @match https://amazon.ae/*
// @match https://www.amazon.com/*
// @match https://www.amazon.co.uk/*
// @match https://www.amazon.de/*
// @match https://www.amazon.fr/*
// @match https://www.amazon.it/*
// @match https://www.amazon.es/*
// @match https://www.amazon.ca/*
// @match https://www.amazon.com.mx/*
// @match https://www.amazon.com.br/*
// @match https://www.amazon.in/*
// @match https://www.amazon.cn/*
// @match https://www.amazon.co.jp/*
// @match https://www.amazon.com.au/*
// @match https://www.amazon.nl/*
// @match https://www.amazon.se/*
// @match https://www.amazon.pl/*
// @match https://www.amazon.sg/*
// @match https://www.amazon.com.tr/*
// @match https://www.amazon.sa/*
// @match https://www.amazon.ae/*
// @grant none
// @run-at document-end
// @homepageURL https://farmazon.app/userscript
// ==/UserScript==
(function() {
'use strict';
/**
* Extract ASIN from the current Amazon product page URL
* @returns {string|null} ASIN if found, null otherwise
*/
function extractAsin() {
const url = window.location.href;
// Pattern to match ASIN in various Amazon URL formats
// ASIN is typically 10 characters: uppercase letters and digits
const patterns = [
/\/dp\/([A-Z0-9]{10})/,
/\/gp\/product\/([A-Z0-9]{10})/,
/\/product\/([A-Z0-9]{10})/,
/\/([A-Z0-9]{10})(?:\/|\?|$)/,
];
for (const pattern of patterns) {
const match = url.match(pattern);
if (match) {
return match[1];
}
}
return null;
}
/**
* Create and inject the Farmazon button
*/
function createFarmazonButton() {
const asin = extractAsin();
if (!asin) {
console.log('Farmazon: No ASIN found on this page');
return;
}
// Check if button already exists
if (document.getElementById('farmazon-button')) {
return;
}
console.log('Farmazon: Found ASIN:', asin);
// Create button container
const buttonContainer = document.createElement('div');
buttonContainer.id = 'farmazon-button';
buttonContainer.style.cssText = `
position: fixed;
bottom: 20px;
right: 20px;
z-index: 10000;
animation: fadeIn 0.3s ease-in;
`;
// Create the button
const button = document.createElement('a');
button.href = `https://farmazon.app/dp/${asin}?autoRefresh=true`;
button.target = '_blank';
button.rel = 'noopener noreferrer';
button.innerHTML = `
<svg width="20" height="20" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg" style="margin-right: 8px; vertical-align: middle;">
<path d="M12 2L2 7L12 12L22 7L12 2Z" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
<path d="M2 17L12 22L22 17" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
<path d="M2 12L12 17L22 12" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
</svg>
Porównaj cenę na Farmazon.app
`;
button.style.cssText = `
display: inline-flex;
align-items: center;
background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
color: white;
padding: 12px 24px;
border-radius: 8px;
text-decoration: none;
font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
font-size: 14px;
font-weight: 600;
box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
transition: all 0.3s ease;
cursor: pointer;
border: none;
`;
// Hover effect
button.addEventListener('mouseenter', () => {
button.style.transform = 'translateY(-2px)';
button.style.boxShadow = '0 6px 16px rgba(102, 126, 234, 0.6)';
});
button.addEventListener('mouseleave', () => {
button.style.transform = 'translateY(0)';
button.style.boxShadow = '0 4px 12px rgba(102, 126, 234, 0.4)';
});
// Add animation keyframes
const style = document.createElement('style');
style.textContent = `
@keyframes fadeIn {
from {
opacity: 0;
transform: translateY(-10px);
}
to {
opacity: 1;
transform: translateY(0);
}
}
`;
document.head.appendChild(style);
buttonContainer.appendChild(button);
document.body.appendChild(buttonContainer);
console.log('Farmazon: Button added successfully');
}
// Wait for page to be fully loaded
if (document.readyState === 'loading') {
document.addEventListener('DOMContentLoaded', createFarmazonButton);
} else {
createFarmazonButton();
}
// Also watch for URL changes (for SPAs)
let lastUrl = location.href;
new MutationObserver(() => {
const url = location.href;
if (url !== lastUrl) {
lastUrl = url;
// Remove old button if exists
const oldButton = document.getElementById('farmazon-button');
if (oldButton) {
oldButton.remove();
}
// Add new button after a short delay to allow page to load
setTimeout(createFarmazonButton, 500);
}
}).observe(document, { subtree: true, childList: true });
})();