<?php
/**
* This file is part of the m1\env library
*
* (c) m1 <hello@milescroxford.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*
* @package m1/env
* @version 2.0.0
* @author Miles Croxford <hello@milescroxford.com>
* @copyright Copyright (c) Miles Croxford <hello@milescroxford.com>
* @license http://github.com/m1/env/blob/master/LICENSE.md
* @link http://github.com/m1/env/blob/master/README.md Documentation
*/
namespace M1\Env\Parser;
use M1\Env\Exception\ParseException;
/**
* The value parser for Env
*
* @since 1.1.0
*/
class VariableParser extends AbstractParser
{
/**
* The regex to get variables '$(VARIABLE)' in .env
* Unescaped: ${(.*?)}
*
* @var string REGEX_ENV_VARIABLE
*/
const REGEX_ENV_VARIABLE = '\\${(.*?)}';
/**
* The symbol for the assign default value parameter expansion
*
* @var string SYMBOL_ASSIGN_DEFAULT_VALUE
*/
const SYMBOL_ASSIGN_DEFAULT_VALUE = '=';
/**
* The symbol for the default value parameter expansion
*
* @var string SYMBOL_DEFAULT_VALUE
*/
const SYMBOL_DEFAULT_VALUE = '-';
/**
* Variables context
*
* @var array
*/
private $context;
/**
* {@inheritdoc}
*
* @param \M1\Env\Parser $parser The parent parser
* @param array $context Variables context
*/
public function __construct($parser, array $context = array())
{
parent::__construct($parser);
$this->context = $context;
}
/**
* Parses a .env variable
*
* @param string $value The value to parse
* @param bool $quoted_string Is the value in a quoted string
*
* @return string The parsed value
*/
public function parse($value, $quoted_string = false)
{
$matches = $this->fetchVariableMatches($value);
if (is_array($matches)) {
if ($this->parser->string_helper->isVariableClone($value, $matches, $quoted_string)) {
return $this->fetchVariable($value, $matches[1][0], $matches, $quoted_string);
}
$value = $this->doReplacements($value, $matches, $quoted_string);
}
return $value;
}
/**
* Get variable matches inside a string
*
* @param string $value The value to parse
*
* @return array The variable matches
*/
private function fetchVariableMatches($value)
{
preg_match_all('/' . self::REGEX_ENV_VARIABLE . '/', $value, $matches);
if (!is_array($matches) || !isset($matches[0]) || empty($matches[0])) {
return false;
}
return $matches;
}
/**
* Parses a .env variable
*
* @param string $value The value to parse
* @param string $variable_name The variable name to get
* @param array $matches The matches of the variables
* @param bool $quoted_string Is the value in a quoted string
*
* @return string The parsed value
* @throws \M1\Env\Exception\ParseException If the variable can not be found
*/
private function fetchVariable($value, $variable_name, $matches, $quoted_string)
{
if ($this->hasParameterExpansion($variable_name)) {
$replacement = $this->fetchParameterExpansion($variable_name);
} elseif ($this->hasVariable($variable_name)) {
$replacement = $this->getVariable($variable_name);
} else {
throw new ParseException(
sprintf('Variable has not been defined: %s', $variable_name),
$value,
$this->parser->line_num
);
}
if ($this->parser->string_helper->isBoolInString($replacement, $quoted_string, count($matches[0]))) {
$replacement = ($replacement) ? 'true' : 'false';
}
return $replacement;
}
/**
* Checks to see if the variable has a parameter expansion
*
* @param string $variable The variable to check
*
* @return bool Does the variable have a parameter expansion
*/
private function hasParameterExpansion($variable)
{
if ((strpos($variable, self::SYMBOL_DEFAULT_VALUE) !== false) ||
(strpos($variable, self::SYMBOL_ASSIGN_DEFAULT_VALUE) !== false)
) {
return true;
}
return false;
}
/**
* Fetches and sets the parameter expansion
*
* @param string $variable_name The parameter expansion inside this to fetch
*
* @return string The parsed value
*/
private function fetchParameterExpansion($variable_name)
{
$parameter_type = $this->fetchParameterExpansionType($variable_name);
list($parameter_symbol, $empty_flag) = $this->fetchParameterExpansionSymbol($variable_name, $parameter_type);
list($variable, $default) = $this->splitVariableDefault($variable_name, $parameter_symbol);
$value = $this->getVariable($variable);
return $this->parseVariableParameter(
$variable,
$default,
$this->hasVariable($variable),
$empty_flag && empty($value),
$parameter_type
);
}
/**
* Fetches the parameter expansion type
*
* @param string $variable_name The parameter expansion type to get from this
*
* @return string The parameter expansion type
*/
private function fetchParameterExpansionType($variable_name)
{
if (strpos($variable_name, self::SYMBOL_ASSIGN_DEFAULT_VALUE) !== false) {
return 'assign_default_value';
}
return 'default_value'; // self::DEFAULT_VALUE_SYMBOL
}
/**
* Fetches the parameter type symbol
*
* @param string $variable_name The variable
* @param string $type The type of parameter expansion
*
* @return array The symbol and if there is a empty check
*/
private function fetchParameterExpansionSymbol($variable_name, $type)
{
$class = new \ReflectionClass($this);
$symbol = $class->getConstant('SYMBOL_'.strtoupper($type));
$pos = strpos($variable_name, $symbol);
$check_empty = substr($variable_name, ($pos - 1), 1) === ":";
if ($check_empty) {
$symbol = sprintf(":%s", $symbol);
}
return array($symbol, $check_empty);
}
/**
* Splits the parameter expansion into variable and default
*
* @param string $variable_name The variable name to split
* @param string $parameter_symbol The parameter expansion symbol
*
* @throws \M1\Env\Exception\ParseException If the parameter expansion if not valid syntax
*
* @return array The split variable and default value
*/
private function splitVariableDefault($variable_name, $parameter_symbol)
{
$variable_default = explode($parameter_symbol, $variable_name, 2);
if (count($variable_default) !== 2 || empty($variable_default[1])) {
throw new ParseException(
'You must have valid parameter expansion syntax, eg. ${parameter:=word}',
$variable_name,
$this->parser->line_num
);
}
return array(trim($variable_default[0]), trim($variable_default[1]));
}
/**
* Parses and sets the variable and default if needed
*
* @param string $variable The variable to parse
* @param string $default The default value
* @param bool $exists Does the variable exist
* @param bool $empty Is there the variable empty if exists and the empty flag is set
* @param string $type The type of parameter expansion
*
* @return string The parsed value
*/
private function parseVariableParameter($variable, $default, $exists, $empty, $type)
{
if ($exists && !$empty) {
return $this->getVariable($variable);
}
return $this->assignVariableParameterDefault($variable, $default, $empty, $type);
}
/**
* Parses and sets the variable parameter to default
*
* @param string $variable The variable to parse
* @param string $default The default value
* @param bool $empty Is there the variable empty if exists and the empty flag is set
* @param string $type The type of parameter expansion
*
* @return string The parsed default value
*/
private function assignVariableParameterDefault($variable, $default, $empty, $type)
{
$default = $this->parser->value_parser->parse($default);
if ($type === "assign_default_value" && $empty) {
$this->parser->lines[$variable] = $default;
}
return $default;
}
/**
* Checks to see if a variable exists
*
* @param string $variable The variable name to get
*
* @return bool
*/
private function hasVariable($variable)
{
if (array_key_exists($variable, $this->parser->lines)) {
return true;
}
if (array_key_exists($variable, $this->context)) {
return true;
}
return false;
}
/**
* Get variable value
*
* @param string $variable
*
* @return mixed
*/
private function getVariable($variable)
{
if (array_key_exists($variable, $this->parser->lines)) {
return $this->parser->lines[$variable];
}
if (array_key_exists($variable, $this->context)) {
return $this->context[$variable];
}
return null;
}
/**
* Do the variable replacements
*
* @param string $value The value to throw an error with if doesn't exist
* @param array $matches The matches of the variables
* @param bool $quoted_string Is the value in a quoted string
*
* @return string The parsed value
*/
public function doReplacements($value, $matches, $quoted_string)
{
$replacements = array();
for ($i = 0; $i <= (count($matches[0]) - 1); $i++) {
$replacement = $this->fetchVariable($value, $matches[1][$i], $matches, $quoted_string);
$replacements[$matches[0][$i]] = $replacement;
}
if (!empty($replacements)) {
$value = strtr($value, $replacements);
}
return $value;
}
}