<?php
/**
 * This source file is part of the open source project
 * ExpressionEngine (https://expressionengine.com)
 *
 * @link      https://expressionengine.com/
 * @copyright Copyright (c) 2003-2022, Packet Tide, LLC (https://www.packettide.com)
 * @license   https://expressionengine.com/license Licensed under Apache License, Version 2.0
 */

namespace ExpressionEngine\Service\Validation;

/**
 * Validation Rule Base
 *
 * Represents a Validation Rule that can be applied to a value during any
 * Validation stage.  This can be either form validation or validation of data
 * before it is committed to the database.  Will be loaded from a validation
 * string of the rule's name (first character lower case).
 *
 * For example, a rule to ensure that a required value is present might be
 * named "required".  It could be set in a validation string with other rules
 * such as "required|password".  The class definition would then look like
 * this::
 *
 * 	class Required extends ValidationRule { ... }
 */
abstract class ValidationRule
{
    const STOP = 'STOP';
    const SKIP = 'SKIP';

    /**
     * @var array Rule parameters
     */
    protected $parameters = array();

    /**
     * @var string Stop/Skipped state
     */
    protected $state = '';

    /**
     * Validate a Value
     *
     * Validate a value against this rule. If it is valid, return TRUE
     * otherwise, return FALSE.
     *
     * @param  mixed   $value  The value to validate.
     * @return boolean Success?
     */
    abstract public function validate($key, $value);

    /**
     * Optional if you need access to other values
     *
     * Defaults to blank since we don't want to store
     * all that information if we're not going to need it.
     */
    public function setAllValues(array $values)
    { /* blank */
    }

    /**
     * Internal: Set any rule parameters
     */
    public function setParameters(array $parameters)
    {
        $this->parameters = $parameters;
    }

    /**
     *
     */
    public function assertParameters()
    {
        $names = func_get_args();

        $count_needed = count($names);
        $count_given = count($this->parameters);

        if ($count_needed > $count_given) {
            $this->throwNeedsParameters(array_slice($names, $count_given));
        }

        return $this->parameters;
    }

    /**
     * Hard failure. Will mark the rule as failed and stop processing rules
     * for this field.
     */
    public function stop()
    {
        $this->state = self::STOP;
    }

    /**
     * Soft failure. Skips the rest of the validation process, but does not
     * mark the rule as failed.
     */
    public function skip()
    {
        $this->state = self::SKIP;
    }

    /**
     * Report hard failure status.
     *
     * @return 	bool	Hard failure or not
     */
    public function isStopped()
    {
        return $this->state == self::STOP;
    }

    /**
     * Report soft failure status.
     *
     * @return 	bool	Soft failure or not
     */
    public function isFailed()
    {
        return $this->state == self::SKIP;
    }

    /**
     *
     */
    public function getName()
    {
        return strtolower(basename(str_replace('\\', '/', get_class($this))));
    }

    /**
     *
     */
    public function getParameters()
    {
        return $this->parameters;
    }

    /**
     *
     */
    public function getLanguageKey()
    {
        return $this->getName();
    }

    /**
     * Return the language data for the validation error.
     */
    public function getLanguageData()
    {
        return array($this->getLanguageKey(), $this->getParameters());
    }

    /**
     *
     */
    protected function throwNeedsParameters($missing = array())
    {
        $rule_id = "the {$this->getName()} validation rule";

        if (count($missing) == 1) {
            throw new \Exception("Missing {$missing[0]} parameter for {$rule_id}.");
        }

        $last = array_pop($missing);
        $init = implode(', ', $missing);

        throw new \Exception("Missing {$init} and {$last} parameters for {$rule_id}.");
    }

    protected function numericOrConstantParameter($param)
    {
        if (is_numeric($param)) {
            return $param;
        }

        if (defined($param)) {
            $value = constant($param);
            foreach ($this->parameters as $i => $p) {
                if ($p === $param) {
                    $this->parameters[$i] = $value;
                }
            }

            return $value;
        }

        return false;
    }
}
