<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Form\Extension\Validator;

use Symfony\Component\Form\FormTypeGuesserInterface;
use Symfony\Component\Form\Guess\Guess;
use Symfony\Component\Form\Guess\TypeGuess;
use Symfony\Component\Form\Guess\ValueGuess;
use Symfony\Component\Validator\Mapping\ClassMetadataFactoryInterface;
use Symfony\Component\Validator\Constraint;

class ValidatorTypeGuesser implements FormTypeGuesserInterface
{
    private $metadataFactory;

    public function __construct(ClassMetadataFactoryInterface $metadataFactory)
    {
        $this->metadataFactory = $metadataFactory;
    }

    /**
     * {@inheritDoc}
     */
    public function guessType($class, $property)
    {
        $guesser = $this;

        return $this->guess($class, $property, function (Constraint $constraint) use ($guesser) {
            return $guesser->guessTypeForConstraint($constraint);
        });
    }

    /**
     * {@inheritDoc}
     */
    public function guessRequired($class, $property)
    {
        $guesser = $this;

        return $this->guess($class, $property, function (Constraint $constraint) use ($guesser) {
            return $guesser->guessRequiredForConstraint($constraint);
        // If we don't find any constraint telling otherwise, we can assume
        // that a field is not required (with LOW_CONFIDENCE)
        }, false);
    }

    /**
     * {@inheritDoc}
     */
    public function guessMaxLength($class, $property)
    {
        $guesser = $this;

        return $this->guess($class, $property, function (Constraint $constraint) use ($guesser) {
            return $guesser->guessMaxLengthForConstraint($constraint);
        });
    }

    /**
     * {@inheritDoc}
     */
    public function guessMinLength($class, $property)
    {
        $guesser = $this;

        return $this->guess($class, $property, function (Constraint $constraint) use ($guesser) {
            return $guesser->guessMinLengthForConstraint($constraint);
        });
    }

    /**
     * Guesses a field class name for a given constraint
     *
     * @param  Constraint $constraint  The constraint to guess for
     *
     * @return TypeGuess  The guessed field class and options
     */
    public function guessTypeForConstraint(Constraint $constraint)
    {
        switch (get_class($constraint)) {
            case 'Symfony\Component\Validator\Constraints\Type':
                switch ($constraint->type) {
                    case 'boolean':
                    case 'bool':
                        return new TypeGuess('checkbox', array(), Guess::MEDIUM_CONFIDENCE);

                    case 'double':
                    case 'float':
                    case 'numeric':
                    case 'real':
                        return new TypeGuess('number', array(), Guess::MEDIUM_CONFIDENCE);

                    case 'integer':
                    case 'int':
                    case 'long':
                        return new TypeGuess('integer', array(), Guess::MEDIUM_CONFIDENCE);

                    case '\DateTime':
                        return new TypeGuess('date', array(), Guess::MEDIUM_CONFIDENCE);

                    case 'string':
                        return new TypeGuess('text', array(), Guess::LOW_CONFIDENCE);
                }
                break;

            case 'Symfony\Component\Validator\Constraints\Country':
                return new TypeGuess('country', array(), Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Date':
                return new TypeGuess('date', array('type' => 'string'), Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\DateTime':
                return new TypeGuess('datetime', array('type' => 'string'), Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Email':
                return new TypeGuess('email', array(), Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\File':
            case 'Symfony\Component\Validator\Constraints\Image':
                return new TypeGuess('file', array(), Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Language':
                return new TypeGuess('language', array(), Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Locale':
                return new TypeGuess('locale', array(), Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Time':
                return new TypeGuess('time', array('type' => 'string'), Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Url':
                return new TypeGuess('url', array(), Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Ip':
                return new TypeGuess('text', array(), Guess::MEDIUM_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\MaxLength':
            case 'Symfony\Component\Validator\Constraints\MinLength':
            case 'Symfony\Component\Validator\Constraints\Regex':
            case 'Symfony\Component\Validator\Constraints\SizeLength':
                return new TypeGuess('text', array(), Guess::LOW_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Min':
            case 'Symfony\Component\Validator\Constraints\Size':
            case 'Symfony\Component\Validator\Constraints\Max':
                return new TypeGuess('number', array(), Guess::LOW_CONFIDENCE);
        }
    }

    /**
     * Guesses whether a field is required based on the given constraint
     *
     * @param  Constraint $constraint  The constraint to guess for
     *
     * @return Guess       The guess whether the field is required
     */
    public function guessRequiredForConstraint(Constraint $constraint)
    {
        switch (get_class($constraint)) {
            case 'Symfony\Component\Validator\Constraints\NotNull':
            case 'Symfony\Component\Validator\Constraints\NotBlank':
                return new ValueGuess(true, Guess::HIGH_CONFIDENCE);
        }
    }

    /**
     * Guesses a field's maximum length based on the given constraint
     *
     * @param  Constraint $constraint  The constraint to guess for
     *
     * @return Guess       The guess for the maximum length
     */
    public function guessMaxLengthForConstraint(Constraint $constraint)
    {
        switch (get_class($constraint)) {
            case 'Symfony\Component\Validator\Constraints\MaxLength':
                return new ValueGuess($constraint->limit, Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\SizeLength':
                return new ValueGuess($constraint->max, Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Type':
                if (in_array($constraint->type, array('double', 'float', 'numeric', 'real'))) {
                        return new ValueGuess(null, Guess::MEDIUM_CONFIDENCE);
                }
                break;

            case 'Symfony\Component\Validator\Constraints\Max':
                return new ValueGuess(strlen((string) $constraint->limit), Guess::LOW_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Size':
                return new ValueGuess(strlen((string) $constraint->max), Guess::LOW_CONFIDENCE);
        }
    }

    /**
     * Guesses a field's minimum length based on the given constraint
     *
     * @param  Constraint $constraint  The constraint to guess for
     *
     * @return Guess       The guess for the minimum length
     */
    public function guessMinLengthForConstraint(Constraint $constraint)
    {
        switch (get_class($constraint)) {
            case 'Symfony\Component\Validator\Constraints\MinLength':
                return new ValueGuess($constraint->limit, Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\SizeLength':
                return new ValueGuess($constraint->min, Guess::HIGH_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Type':
                if (in_array($constraint->type, array('double', 'float', 'numeric', 'real'))) {
                    return new ValueGuess(null, Guess::MEDIUM_CONFIDENCE);
                }
                break;

            case 'Symfony\Component\Validator\Constraints\Min':
                return new ValueGuess(strlen((string) $constraint->limit), Guess::LOW_CONFIDENCE);

            case 'Symfony\Component\Validator\Constraints\Size':
                return new ValueGuess(strlen((string) $constraint->min), Guess::LOW_CONFIDENCE);
        }
    }

    /**
     * Iterates over the constraints of a property, executes a constraints on
     * them and returns the best guess
     *
     * @param  string   $class     The class to read the constraints from
     * @param  string   $property  The property for which to find constraints
     * @param  \Closure $closure   The closure that returns a guess
     *                             for a given constraint
     * @param  mixed    $default   The default value assumed if no other value
     *                             can be guessed.
     *
     * @return Guess  The guessed value with the highest confidence
     */
    protected function guess($class, $property, \Closure $closure, $defaultValue = null)
    {
        $guesses = array();
        $classMetadata = $this->metadataFactory->getClassMetadata($class);

        if ($classMetadata->hasMemberMetadatas($property)) {
            $memberMetadatas = $classMetadata->getMemberMetadatas($property);

            foreach ($memberMetadatas as $memberMetadata) {
                $constraints = $memberMetadata->getConstraints();

                foreach ($constraints as $constraint) {
                    if ($guess = $closure($constraint)) {
                        $guesses[] = $guess;
                    }
                }
            }

            if (null !== $defaultValue) {
                $guesses[] = new ValueGuess($defaultValue, Guess::LOW_CONFIDENCE);
            }
        }

        return Guess::getBestGuess($guesses);
    }
}