Combo of Rosemary + Jojoba

<?php
// Get the current product
global $product;

// Check if we're on a product page and have a product
if (!is_product() || !$product) {
    return;
}

// Check if it's a variable product
if (!$product->is_type('variable')) {
    return;
}

// Get variation data to access prices
$variations = $product->get_available_variations();
$variation_prices = array();

// Find the 100ml and 200ml variations and their prices
foreach ($variations as $variation) {
    $attributes = $variation['attributes'];
    
    // Check for size attribute
    if (isset($attributes['attribute_pa_size'])) {
        $size_value = $attributes['attribute_pa_size'];
        
        if (strpos($size_value, '100') !== false || strpos($size_value, '100-ml') !== false) {
            $variation_prices['100'] = $variation['display_price'];
        } elseif (strpos($size_value, '200') !== false || strpos($size_value, '200-ml') !== false) {
            $variation_prices['200'] = $variation['display_price'];
        }
    }
}

// Format prices with currency symbol
$formatted_prices = array();
if (isset($variation_prices['100'])) {
    $formatted_prices['100'] = wc_price($variation_prices['100']);
}
if (isset($variation_prices['200'])) {
    $formatted_prices['200'] = wc_price($variation_prices['200']);
}

// Get current price (default to 100ML)
$current_price = isset($formatted_prices['100']) ? $formatted_prices['100'] : '';
?>

<!-- Add a div to show the current price -->
<div class="single-price-display">
    <?php echo $current_price; ?>
</div>

<!-- Original size terms hidden but functional -->
<div class="original-size-terms" style="position: absolute; opacity: 0; pointer-events: none; height: 0; overflow: hidden;">
    <?php echo do_shortcode(''); ?>
</div>

/* Hide the original price range in specific places */
.woocommerce-variation-price {
    display: none !important;
}

/* Price display styles */
.single-price-display {
    font-size: 24px;
    font-weight: 600;
    margin: 15px 0;
    display: block !important;
}

/* Make sure the 100 ML button appears selected by default */
.woocommerce div.product form.cart .button-variable-item[data-value="100-ml"],
button[data-value="100-ml"],
a[data-value="100-ml"],
.button-wrapper [data-value="100-ml"],
.size-option[data-value="100-ml"] {
    background-color: #333 !important;
    color: white !important;
    border-color: #333 !important;
}

/* Make sure both size buttons are clickable */
.button-variable-wrapper .button-variable-item,
.button-wrapper button,
.size-option {
    cursor: pointer !important;
    pointer-events: auto !important;
}

/* Remove any disabled styles */
.button-variable-item.disabled,
button.disabled,
.disabled {
    opacity: 1 !important;
    pointer-events: auto !important;
}

document.addEventListener('DOMContentLoaded', function() {
    // Wait for the page to fully load
    setTimeout(function() {
        // Hide the original price range display
        const priceRanges = document.querySelectorAll('.price-range, .woocommerce-variation-price');
        priceRanges.forEach(el => {
            el.style.display = 'none';
        });
        
        // Find price display element
        const priceDisplay = document.querySelector('.single-price-display');
        
        // Pricing data from PHP
        const pricingData = {
            <?php if (isset($formatted_prices['100'])): ?>
            '100': '<?php echo addslashes($formatted_prices['100']); ?>',
            <?php endif; ?>
            <?php if (isset($formatted_prices['200'])): ?>
            '200': '<?php echo addslashes($formatted_prices['200']); ?>'
            <?php endif; ?>
        };
        
        // Find size buttons/options - try multiple selectors
        const sizeOptions = document.querySelectorAll('.button-variable-item, [data-attribute="pa_size"] [data-value], .size-option, button[data-value]');
        
        // Map sizes to their elements
        const sizeMap = {};
        sizeOptions.forEach(option => {
            let sizeValue = option.getAttribute('data-value') || '';
            if (sizeValue.includes('100')) {
                sizeMap['100'] = option;
            } else if (sizeValue.includes('200')) {
                sizeMap['200'] = option;
            }
        });
        
        // Ensure the 100 ML option is selected by default
        if (sizeMap['100']) {
            // Force click the 100 ML button
            setTimeout(() => {
                try {
                    sizeMap['100'].click();
                } catch (e) {
                    console.log('Could not click 100 ML option');
                }
            }, 100);
        }
        
        // Add click handlers to update price display
        sizeOptions.forEach(option => {
            option.addEventListener('click', function() {
                const value = this.getAttribute('data-value') || '';
                
                // Update styling for all buttons
                sizeOptions.forEach(btn => {
                    btn.style.backgroundColor = '';
                    btn.style.color = '';
                });
                
                // Set styling for clicked button
                this.style.backgroundColor = '#333';
                this.style.color = 'white';
                
                // Update price based on selection
                if (value.includes('100') && pricingData['100']) {
                    priceDisplay.innerHTML = pricingData['100'];
                } else if (value.includes('200') && pricingData['200']) {
                    priceDisplay.innerHTML = pricingData['200'];
                }
            });
        });
        
        // Make sure variation form is initialized
        if (typeof jQuery !== 'undefined') {
            jQuery('form.variations_form').on('woocommerce_variation_has_changed', function() {
                // Get the current variation
                const variation = jQuery('input[name="variation_id"]').val();
                if (variation) {
                    // Check which size is selected
                    const sizeValue = jQuery('select[name="attribute_pa_size"]').val() || '';
                    
                    if (sizeValue.includes('100') && pricingData['100']) {
                        priceDisplay.innerHTML = pricingData['100'];
                    } else if (sizeValue.includes('200') && pricingData['200']) {
                        priceDisplay.innerHTML = pricingData['200'];
                    }
                }
            });
            
            // Initialize form
            jQuery('form.variations_form').trigger('check_variations');
        }
        
        // Create a hidden select for the size attribute if needed
        const variationForm = document.querySelector('.variations_form');
        if (variationForm && !document.querySelector('select[name="attribute_pa_size"]')) {
            const sizeSelect = document.createElement('select');
            sizeSelect.name = 'attribute_pa_size';
            sizeSelect.style.display = 'none';
            
            // Add options
            const option100 = document.createElement('option');
            option100.value = '100-ml';
            option100.text = '100 ML';
            
            const option200 = document.createElement('option');
            option200.value = '200-ml';
            option200.text = '200 ML';
            
            sizeSelect.appendChild(option100);
            sizeSelect.appendChild(option200);
            
            // Set default
            sizeSelect.value = '100-ml';
            
            // Add to form
            variationForm.appendChild(sizeSelect);
            
            // Trigger change
            if (typeof jQuery !== 'undefined') {
                jQuery(sizeSelect).trigger('change');
            }
        }
    }, 300);
});