<?php

/**
 * Enables text extraction of file content via the Tika Rest Server
 *
 * {@link http://tika.apache.org/1.7/gettingstarted.html}
 */
class TikaServerTextExtractor extends FileTextExtractor {

	/**
	 * Tika server is pretty efficient so use it immediately if available
	 *
	 * @var integer
	 * @config
	 */
	private static $priority = 80;

	/**
	 * Server endpoint
	 *
	 * @var string
	 * @config
	 */
	private static $server_endpoint;

	/**
	 * @var TikaRestClient
	 */
	protected $client = null;

	/**
	 * @return TikaRestClient
	 */
	public function getClient() {
		return $this->client ?:
			($this->client =
				Injector::inst()->createWithArgs(
					'TikaRestClient',
					array($this->getServerEndpoint())
				)
			);
	}

	public function getServerEndpoint() {
		if(defined('SS_TIKA_ENDPOINT')) {
			return SS_TIKA_ENDPOINT;
		}

		if(getenv('SS_TIKA_ENDPOINT')) return getenv('SS_TIKA_ENDPOINT');

		// Default to configured endpoint
		return $this->config()->server_endpoint;
	}

	/**
	 * Get the version of tika installed, or 0 if not installed
	 *
	 * @return float version of tika
	 */
	public function getVersion() {
		return $this
			->getClient()
			->getVersion();
	}

	public function isAvailable() {
		return $this->getServerEndpoint() &&
			$this->getClient()->isAvailable() &&
			$this->getVersion() >= 1.7;
	}

	public function supportsExtension($extension) {
		// Determine support via mime type only
		return false;
	}


	/**
	 * Cache of supported mime types
	 *
	 * @var array
	 */
	protected $supportedMimes = array();

	public function supportsMime($mime) {
		$supported = $this->supportedMimes ?:
			($this->supportedMimes = $this->getClient()->getSupportedMimes());

		// Check if supported (most common / quickest lookup)
		if(isset($supported[$mime])) return true;

		// Check aliases
		foreach($supported as $info) {
			if(isset($info['alias']) && in_array($mime, $info['alias'])) return true;
		}

		return false;
	}

	public function getContent($path) {
		return $this->getClient()->tika($path);
	}

}