Dynamically Create Schema.org code for head section of a Magento 1.9 website.

head.phtml

<?php
/**
 * Magento
 *
 * NOTICE OF LICENSE
 *
 * This source file is subject to the Academic Free License (AFL 3.0)
 * that is bundled with this package in the file LICENSE_AFL.txt.
 * It is also available through the world-wide-web at this URL:
 * http://opensource.org/licenses/afl-3.0.php
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@magento.com so we can send you a copy immediately.
 *
 * DISCLAIMER
 *
 * Do not edit or add to this file if you wish to upgrade Magento to newer
 * versions in the future. If you wish to customize Magento for your
 * needs please refer to http://www.magento.com for more information.
 *
 * @category    design
 * @package     base_default
 * @copyright   Copyright (c) 2006-2014 X.commerce, Inc. (http://www.magento.com)
 * @license     http://opensource.org/licenses/afl-3.0.php  Academic Free License (AFL 3.0)
 */
?>
<meta http-equiv="Content-Type" content="<?php echo $this->getContentType() ?>" />
<title><?php echo $this->getTitle() ?></title>
<!-- Schema.org Begin -->
<?php if(Mage::helper('core/url')->getCurrentUrl() === $this->getBaseUrl()): ?>
<!-- Schema.org Homepage Page Begin -->
    <script type="application/ld+json">
    {
        "@context": "http://schema.org",
        "@type": "Organization",
        "logo": "<?php echo $this->getBaseUrl() . 'media/images/logo_small.jpg'; ?>",
        "description": "<?php echo str_replace('&amp;', 'and',htmlspecialchars($this->getDescription())) ?>",
        "mainEntityOfPage": "<?php echo $this->helper('core/url')->getCurrentUrl();?>",
        "url": "<?php echo $this->getBaseUrl(); ?>",
        "sameAs": [
                "https://www.facebook.com/",
                "https://twitter.com/",
                "https://plus.google.com/",
                "https://www.youtube.com/user/",
                "https://www.pinterest.com/"
        ],
        "brand": {
            "@type": "http://schema.org/Brand",
            "name": "Brand Name"
        },
        "potentialAction": {
            "@type": "SearchAction",
            "target": "https://domain.com/query/path/?q={search_term_string}",
            "query-input": "required name=search_term_string"
        }
    }
    </script>
<!-- Schema.org Homepage Page End -->
<?php elseif(Mage::registry('current_category') && !Mage::registry('current_product')): ?>
<!-- Schema.org Category Page Begin -->
	<?php
		//Get current category from registry
		$currentCategory = Mage::registry('current_category');
		//Display the current Category Title
		$categoryCategoryName = $currentCategory->getName();
	?>
	<script type="application/ld+json">
    {
        "@context": "http://schema.org",
        "@type": "SomeProducts",
        "description": "<?php echo str_replace('"',"''",strip_tags(($currentCategory->getMetaDescription()))); ?>",
        "name": "<?php echo $categoryCategoryName; ?>",
        "logo": "<?php echo $this->getBaseUrl() . 'media/images/logo_small.jpg'; ?>",
        "url": "<?php echo $this->helper('core/url')->getCurrentUrl();?>",
        "sameAs": [
                "https://www.facebook.com/",
                "https://twitter.com/",
                "https://plus.google.com/",
                "https://www.youtube.com/user/",
                "https://www.pinterest.com/"
        ],
        "mainEntityOfPage": "<?php echo $this->getBaseUrl(); ?>",
        "brand": {
            "@type": "http://schema.org/Brand",
            "name": "Brand Name"
        },
        "category": {
            "@type": "http://schema.org/Thing",
            "name": "<?php echo $categoryCategoryName; ?>"
        }
    }
    </script>
<!-- Schema.org Category Page End -->
<?php elseif(Mage::registry('current_product')): ?>
<!-- Schema.org Product Page Begin -->
	<?php
		$product = Mage::registry('current_product');
		$categoryIds = $product->getCategoryIds();
		foreach($categoryIds as $categoryId) {
    		$category = Mage::getModel('catalog/category')->load($categoryId);
    		$productCategoryName = $category->getName();
    	}
    ?>
	<script type="application/ld+json">
	{
        "@context": "http://schema.org",
        "@type": "Product",
        "name": "<?php echo str_replace(array(',', '"'), array('-', 'inch'), $product->getName()); ?>",
        "description": "<?php echo str_replace('"',"''",strip_tags(($product->getDescription()))); ?>",
        "image": "<?php echo $this->helper('catalog/image')->init($product, 'small_image')->resize(200,200); ?>",
        "sku": "<?php echo $product->getSku(); ?>",
        "itemCondition": "NewCondition",
        "mainEntityOfPage": "<?php echo Mage::registry('product')->getProductUrl(); ?>",
        "manufacturer": {
                    "@type": "Organization",
                    "name": "Manufacturer Name"
                },
        "logo": "<?php echo $this->getBaseUrl() . 'media/images/logo_small.jpg'; ?>",
        "url": "<?php echo $this->getBaseUrl(); ?>",
        "sameAs": [
                "https://www.facebook.com/",
                "https://twitter.com/",
                "https://plus.google.com/",
                "https://www.youtube.com/user/",
                "https://www.pinterest.com/"
        ],
        "@context": "http://schema.org",
        "@type": "Product",
        "brand": {
            "@type": "http://schema.org/Brand",
            "name": "Brand Name"
        },
        "category": {
            "@type": "http://schema.org/Thing",
            "name": "<?php echo $productCategoryName; ?>"
        }
    }
	</script>
<!-- Schema.org Product Page End -->
<?php else: ?>
<!-- Schema.org Normal Page Begin -->
	<script type="application/ld+json">
	{
        "@context": "http://schema.org",
        "@type": "Organization",
        "description": "<?php echo str_replace('&amp;', 'and', htmlspecialchars($this->getDescription())) ?>",
        "logo": "<?php echo $this->getBaseUrl() . 'media/images/logo_small.jpg'; ?>",
        "mainEntityOfPage": "<?php echo Mage::helper('core/url')->getCurrentUrl(); ?>",
        "name": "Organization Name",
        "alternateName": "Organization Name",
        "url": "<?php echo $this->getBaseUrl(); ?>",
        "sameAs": [
                "https://www.facebook.com/",
                "https://twitter.com/",
                "https://plus.google.com/",
                "https://www.youtube.com/user/",
                "https://www.pinterest.com/"
        ],
        "brand": {
            "@type": "http://schema.org/Brand",
            "name": "Brand Name",
            "url": "<?php echo $this->getBaseUrl(); ?>"
        }
    }
	</script>
<!-- Schema.org Normal Page End -->
<?php endif; ?>
<!-- Schema.org End -->
<!-- Facebook Opengraph Begin -->
<!-- Facebook Opengraph Product Page Begin -->
<?php if(Mage::registry('current_product')): ?>
	<?php $product = Mage::registry('current_product'); ?>
	<meta property="og:title" content="<?php echo str_replace('"',"'",$product->getName()); ?>" />
	<meta property="og:type"  content="product" />
	<meta property="og:image" content="<?php echo $this->helper('catalog/image')->init($product, 'small_image')->resize(200,200);?>" />
	<meta property="og:url"   content="<?php echo Mage::registry('product')->getProductUrl(); ?>" />
	<meta property="og:description" name="description" content="<?php echo str_replace('"',"''",strip_tags(($product->getMetaDescription()))); ?>" />
<!-- Facebook Opengraph Product Page End -->
<!-- Facebook Opengraph Product Category Begin -->
<?php elseif(Mage::registry('current_category')): ?>
	 <meta property="og:title" content="<?php echo str_replace('"',"'",$this->getTitle()) ?>" />
	 <meta property="og:type" content="product.group" />
	 <meta property="og:url" content="<?php echo $this->helper('core/url')->getCurrentUrl();?>" />
	 <meta property="og:description" name="description" content="<?php echo str_replace('"',"''",strip_tags($this->getDescription())) ?>" />
<!-- Facebook Opengraph Product Category End -->
<!-- Facebook Opengraph Normal Pages Begin -->
<?php else: ?>
	<meta property="og:url" content="<?php echo Mage::helper('core/url')->getCurrentUrl(); ?>" />
	<meta property="og:image" content="<?php echo $this->getSkinUrl(Mage::getStoreConfig('design/header/logo_src')); ?>" />
	<meta name="description" content="<?php echo htmlspecialchars($this->getDescription()) ?>" />
<?php endif; ?>
<!-- Facebook Opengraph Normal Pages End -->
<meta property="og:site_name" content="<?php echo Mage::getStoreConfig('general/store_information/name'); ?>" />
<!-- Facebook Opengraph End -->
<?php if(htmlspecialchars($this->getKeywords()) != ""): ?>
<meta name="keywords" content="<?php echo htmlspecialchars($this->getKeywords()) ?>" />
<?php endif; ?>

<meta name="robots" content="<?php echo htmlspecialchars($this->getRobots()) ?>" />
<?php //<meta name="viewport" content="width=device-width, initial-scale=1">php ?>
<link rel="icon" href="<?php echo $this->getFaviconFile(); ?>" type="image/x-icon" />
<link rel="shortcut icon" href="<?php echo $this->getFaviconFile(); ?>" type="image/x-icon" />
<link rel='publisher'  href='https://plus.google.com/' />
<!--[if lt IE 7]>
<script type="text/javascript">
//<![CDATA[
    var BLANK_URL = '<?php echo $this->helper('core/js')->getJsUrl('blank.html') ?>';
    var BLANK_IMG = '<?php echo $this->helper('core/js')->getJsUrl('spacer.gif') ?>';
//]]>
</script>
<![endif]-->
<?php echo $this->getCssJsHtml() ?>
<?php echo $this->getChildHtml() ?>
<?php echo $this->helper('core/js')->getTranslatorScript() ?>
<?php echo $this->getIncludes() ?>