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<?php

/**
 * Turn mimetype into font awesome file icon name (e.g. file-text-o)
 * @param  string $mimetype File mimetype
 * @return string           Font Awesome file icon name 
 */
function mimetype2FontAwesome($mimetype = null) {

	switch( $mimetype ) {

		// PDF
		case 'application/pdf':
			return 'file-pdf-o';
		break;

		// Plain text
		case 'text/plain':
			return 'file-text-o';
		break;

		// Audio
		case 'audio/basic':
		case 'audio/L24':
		case 'audio/mp4':
		case 'audio/mpeg':
		case 'audio/ogg':
		case 'audio/flac':
		case 'audio/opus':
		case 'audio/vorbis':
		case 'audio/vnd.rn-realaudio':
		case 'audio/vnd.wave':
		case 'audio/webm':
		case 'audio/x-aac':
		case 'audio/x-caf':
			return 'file-audio-o';
		break;

		// Video
		case 'video/avi':
		case 'video/mpeg':
		case 'video/mp4':
		case 'video/ogg':
		case 'video/quicktime':
		case 'video/webm':
		case 'video/x-matroska':
		case 'video/x-ms-wmv':
		case 'video/x-fkv':
			return 'file-video-o';
		break;

				// Powerpoint
		case 'application/vnd.ms-powerpoint':
		case 'application/vnd.openxmlformats-officedocument.presentationml.presentation':
		case 'application/vnd.openxmlformats-officedocument.presentationml.template':
		case 'application/vnd.openxmlformats-officedocument.presentationml.slideshow':
		case 'application/vnd.ms-powerpoint.addin.macroEnabled.12':
		case 'application/vnd.ms-powerpoint.presentation.macroEnabled.12':
		case 'application/vnd.ms-powerpoint.template.macroEnabled.12':
		case 'application/vnd.ms-powerpoint.slideshow.macroEnabled.12':
			return 'file-powerpoint-o';
		break;

				// Word
		case 'application/msword':
		case 'application/vnd.openxmlformats-officedocument.wordprocessingml.template':
		case 'application/vnd.openxmlformats-officedocument.wordprocessingml.document':
		case 'application/vnd.ms-word.document.macroEnabled.12':
		case 'application/vnd.ms-word.template.macroEnabled.12':
			return 'file-word-o';
		break;

		// Excel
		case 'application/vnd.ms-excel':
		case 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet':
		case 'application/vnd.openxmlformats-officedocument.spreadsheetml.template':
		case 'application/vnd.ms-excel.sheet.macroEnabled.12':
		case 'application/vnd.ms-excel.template.macroEnabled.12':
		case 'application/vnd.ms-excel.addin.macroEnabled.12':
		case 'application/vnd.ms-excel.sheet.binary.macroEnabled.12':
		case 'text/csv':
			return 'file-excel-o';
		break;

		case 'application/json':
		case 'application/javascript':
		case 'application/xhtml+xml':
		case 'application/xml':
		case 'text/xml':
		case 'text/javascript':
		case 'text/html':
		case 'text/cmd':
		case 'text/css':
		case 'text/vcard':
		case 'text/x-markdown':
		case 'text/x-jquery-tmpl':
			return 'file-code-o';
		break;

		// Archive
		case 'application/x-rar-compressed':
		case 'application/x-7z-compressed':
		case 'application/zip':
		case 'application/gzip':
			return 'file-archive-o';
		break;

		// Image
		case 'image/gif':
		case 'image/jpeg':
		case 'image/png':
		case 'image/bmp':
		case 'image/svg+xml':
		case 'image/tiff':
		case 'image/vnd.djvu':
		case 'image/x-xcf':
			return 'file-image-o';
		break;

		// All the others
		default:
			return 'file';
		break;
	}
}

?>
<!-- Sample usage -->
<i class="fa fa-<?php echo mimetype2FontAwesome('application/zip'); ?>"></i>