<?php

namespace Dotenv;

use Dotenv\Exception\InvalidCallbackException;
use Dotenv\Exception\ValidationException;

/**
* This is the validator class.
*
* It's responsible for applying validations against a number of variables.
*/
class Validator
{
/**
* The variables to validate.
*
* @var array
*/
protected $variables;

/**
* The loader instance.
*
* @var \Dotenv\Loader
*/
protected $loader;

/**
* Create a new validator instance.
*
* @param array $variables
* @param \Dotenv\Loader $loader
*
* @return void
*/
public function __construct(array $variables, Loader $loader)
{
$this->variables = $variables;
$this->loader = $loader;

$this->assertCallback(
function ($value) {
return $value !== null;
},
'is missing'
);
}

/**
* Assert that each variable is not empty.
*
* @return \Dotenv\Validator
*/
public function notEmpty()
{
return $this->assertCallback(
function ($value) {
return strlen(trim($value)) > 0;
},
'is empty'
);
}

/**
* Assert that each specified variable is an integer.
*
* @return \Dotenv\Validator
*/
public function isInteger()
{
return $this->assertCallback(
function ($value) {
return ctype_digit($value);
},
'is not an integer'
);
}

/**
* Assert that each specified variable is a boolean.
*
* @return \Dotenv\Validator
*/
public function isBoolean()
{
return $this->assertCallback(
function ($value) {
if ($value === '') {
return false;
}

return filter_var($value, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE) !== null;
},
'is not a boolean'
);
}

/**
* Assert that each variable is amongst the given choices.
*
* @param string[] $choices
*
* @return \Dotenv\Validator
*/
public function allowedValues(array $choices)
{
return $this->assertCallback(
function ($value) use ($choices) {
return in_array($value, $choices);
},
'is not an allowed value'
);
}

/**
* Assert that the callback returns true for each variable.
*
* @param callable $callback
* @param string $message
*
* @throws \Dotenv\Exception\InvalidCallbackException|\Dotenv\Exception\ValidationException
*
* @return \Dotenv\Validator
*/
protected function assertCallback($callback, $message = 'failed callback assertion')
{
if (!is_callable($callback)) {
throw new InvalidCallbackException('The provided callback must be callable.');
}

$variablesFailingAssertion = array();
foreach ($this->variables as $variableName) {
$variableValue = $this->loader->getEnvironmentVariable($variableName);
if (call_user_func($callback, $variableValue) === false) {
$variablesFailingAssertion[] = $variableName." $message";
}
}

if (count($variablesFailingAssertion) > 0) {
throw new ValidationException(sprintf(
'One or more environment variables failed assertions: %s.',
implode(', ', $variablesFailingAssertion)
));
}

return $this;
}
}