EditPostLink_InstallIndicator.php

<?php
include_once('EditPostLink_OptionsManager.php');

class EditPostLink_InstallIndicator extends EditPostLink_OptionsManager {

	const optionInstalled = '_installed';
	const optionVersion = '_version';

	/**
	 * @return bool indicating if the plugin is installed already
	 */
	public function isInstalled() {
		return $this->getOption(self::optionInstalled) == true;
	}

	/**
	 * Note in DB that the plugin is installed
	 * @return null
	 */
	protected function markAsInstalled() {
		return $this->updateOption(self::optionInstalled, true);
	}

	/**
	 * Note in DB that the plugin is uninstalled
	 * @return bool returned form delete_option.
	 * true implies the plugin was installed at the time of this call,
	 * false implies it was not.
	 */
	protected function markAsUnInstalled() {
		return $this->deleteOption(self::optionInstalled);
	}

	/**
	 * Set a version string in the options. This is useful if you install upgrade and
	 * need to check if an older version was installed to see if you need to do certain
	 * upgrade housekeeping (e.g. changes to DB schema).
	 * @return null
	 */
	protected function getVersionSaved() {
		return $this->getOption(self::optionVersion);
	}

	/**
	 * Set a version string in the options.
	 * need to check if
	 * @param  $version string best practice: use a dot-delimited string like '1.2.3' so version strings can be easily
	 * compared using version_compare (http://php.net/manual/en/function.version-compare.php)
	 * @return null
	 */
	protected function setVersionSaved($version) {
		return $this->updateOption(self::optionVersion, $version);
	}

	/**
	 * @return string name of the main plugin file that has the header section with
	 * "Plugin Name", "Version", "Description", "Text Domain", etc.
	 */
	protected function getMainPluginFileName() {
		return basename(dirname(__FILE__)) . 'php';
	}

	/**
	 * Get a value for input key in the header section of main plugin file.
	 * E.g. "Plugin Name", "Version", "Description", "Text Domain", etc.
	 * @param $key string plugin header key
	 * @return string if found, otherwise null
	 */
	public function getPluginHeaderValue($key) {
		// Read the string from the comment header of the main plugin file
		$data = file_get_contents($this->getPluginDir() . DIRECTORY_SEPARATOR . $this->getMainPluginFileName());
		$match = array();
		preg_match('/' . $key . ':\s*(\S+)/', $data, $match);
		if (count($match) >= 1) {
			return $match[1];
		}
		return null;
	}

	/**
	 * If your subclass of this class lives in a different directory,
	 * override this method with the exact same code. Since __FILE__ will
	 * be different, you will then get the right dir returned.
	 * @return string
	 */
	protected function getPluginDir() {
		return dirname(__FILE__);
	}

	/**
	 * Version of this code.
	 * Best practice: define version strings to be easily compared using version_compare()
	 * (http://php.net/manual/en/function.version-compare.php)
	 * NOTE: You should manually make this match the SVN tag for your main plugin file 'Version' release and 'Stable tag' in readme.txt
	 * @return string
	 */
	public function getVersion() {
		return $this->getPluginHeaderValue('Version');
	}


	/**
	 * Useful when checking for upgrades, can tell if the currently installed version is earlier than the
	 * newly installed code. This case indicates that an upgrade has been installed and this is the first time it
	 * has been activated, so any upgrade actions should be taken.
	 * @return bool true if the version saved in the options is earlier than the version declared in getVersion().
	 * true indicates that new code is installed and this is the first time it is activated, so upgrade actions
	 * should be taken. Assumes that version string comparable by version_compare, examples: '1', '1.1', '1.1.1', '2.0', etc.
	 */
	public function isInstalledCodeAnUpgrade() {
		return $this->isSavedVersionLessThan($this->getVersion());
	}

	/**
	 * Used to see if the installed code is an earlier version than the input version
	 * @param  $aVersion string
	 * @return bool true if the saved version is earlier (by natural order) than the input version
	 */
	public function isSavedVersionLessThan($aVersion) {
		return $this->isVersionLessThan($this->getVersionSaved(), $aVersion);
	}

	/**
	 * Used to see if the installed code is the same or earlier than the input version.
	 * Useful when checking for an upgrade. If you haven't specified the number of the newer version yet,
	 * but the last version (installed) was 2.3 (for example) you could check if
	 * For example, $this->isSavedVersionLessThanEqual('2.3') == true indicates that the saved version is not upgraded
	 * past 2.3 yet and therefore you would perform some appropriate upgrade action.
	 * @param  $aVersion string
	 * @return bool true if the saved version is earlier (by natural order) than the input version
	 */
	public function isSavedVersionLessThanEqual($aVersion) {
		return $this->isVersionLessThanEqual($this->getVersionSaved(), $aVersion);
	}

	/**
	 * @param  $version1 string a version string such as '1', '1.1', '1.1.1', '2.0', etc.
	 * @param  $version2 string a version string such as '1', '1.1', '1.1.1', '2.0', etc.
	 * @return bool true if version_compare of $versions1 and $version2 shows $version1 as the same or earlier
	 */
	public function isVersionLessThanEqual($version1, $version2) {
		return (version_compare($version1, $version2) <= 0);
	}

	/**
	 * @param  $version1 string a version string such as '1', '1.1', '1.1.1', '2.0', etc.
	 * @param  $version2 string a version string such as '1', '1.1', '1.1.1', '2.0', etc.
	 * @return bool true if version_compare of $versions1 and $version2 shows $version1 as earlier
	 */
	public function isVersionLessThan($version1, $version2) {
		return (version_compare($version1, $version2) < 0);
	}

	/**
	 * Record the installed version to options.
	 * This helps track was version is installed so when an upgrade is installed, it should call this when finished
	 * upgrading to record the new current version
	 * @return void
	 */
	protected function saveInstalledVersion() {
		$this->setVersionSaved($this->getVersion());
	}


}