src/BuildWpQueryArgsCapableTrait.php
<?php
namespace RebelCode\WordPress\Query\Builder;
use Dhii\Expression\LogicalExpressionInterface;
use Dhii\Expression\Type\BooleanTypeInterface;
use Dhii\Util\String\StringableInterface as Stringable;
use Exception as RootException;
use InvalidArgumentException;
use OutOfRangeException;
/**
* Common functionality for objects that can build expressions into
* {@link https://codex.wordpress.org/Class_Reference/WP_Query `WP_Query`} array arguments.
*
* @since [*next-version*]
*/
trait BuildWpQueryArgsCapableTrait
{
/**
* Builds a given expression into array arguments that can be passed to `WP_Query`.
*
* @since [*next-version*]
*
* @param LogicalExpressionInterface $expression The expression to build into the `WP_Query` array argument.
*
* @throws OutOfRangeException If the given expression or any of its terms are not supported.
*
* @return array The resulting `WP_Query` array argument.
*/
protected function _buildWpQueryArgs(LogicalExpressionInterface $expression)
{
if (!$this->_isWpQueryExpressionSupported($expression)) {
throw $this->_createOutOfRangeException(
$this->__('Expression is not supported'),
null,
null,
$expression
);
}
$query = [];
foreach ($expression->getTerms() as $_term) {
if (!($_term instanceof LogicalExpressionInterface)) {
throw $this->_createOutOfRangeException(
$this->__('Expression term is not a logical expression'),
null,
null,
$_term
);
}
$query = array_merge($query, $this->_attemptBuildWpQueryArgsTerm($_term));
}
return $query;
}
/**
* Attempts to build an expression as top-level `WP_Query` args term.
*
* This algorithm exploits the fact that the delegate build methods are meant to throw exceptions on failure.
* Catching an exception therefore means that the expression cannot be built using that method, and so the
* algorithm attempts to use another.
*
* @since [*next-version*]
*
* @param LogicalExpressionInterface $expression The expression to attempt to build.
*
* @throws OutOfRangeException If no building mechanism could be determined for the given expression.
*
* @return array The resulting array, as a portion of the final result.
*/
protected function _attemptBuildWpQueryArgsTerm(LogicalExpressionInterface $expression)
{
// Attempt to build as a meta query
try {
return ['meta_query' => $this->_buildWpQueryMetaRelation($expression)];
} catch (OutOfRangeException $exception) {
}
// Attempt to build as a taxonomy query
try {
return ['tax_query' => $this->_buildWpQueryTaxRelation($expression)];
} catch (OutOfRangeException $exception) {
}
// Attempt to build as a top-level compare key-value entry
try {
return $this->_buildWpQueryCompare($expression);
} catch (OutOfRangeException $exception) {
}
throw $this->_createOutOfRangeException(
$this->__('Expression could not be built - no supported build method found'),
null,
null,
$expression
);
}
/**
* Checks whether a given expression is supported for building WP_Query array arguments.
*
* @since [*next-version*]
*
* @param LogicalExpressionInterface $expression The expression instance to check.
*
* @return bool True if the expression is supported, false if not.
*/
protected function _isWpQueryExpressionSupported(LogicalExpressionInterface $expression)
{
return $this->_normalizeString($expression->getType()) === BooleanTypeInterface::T_AND;
}
/**
* Builds a given logical expression into a WP_Query compare array args portion.
*
* @since [*next-version*]
*
* @param LogicalExpressionInterface $expression The expression to build.
*
* @throws OutOfRangeException If the given expression could not be built into a WP_Query compare.
*
* @return array The built expression, as the sub-array portion that represents it in WP_Query args.
*/
abstract protected function _buildWpQueryCompare(LogicalExpressionInterface $expression);
/**
* Builds a given logical expression into a WP_Query meta relation array args portion.
*
* @since [*next-version*]
*
* @param LogicalExpressionInterface $expression The expression to build.
*
* @throws OutOfRangeException If the given expression could not be built into a WP_Query meta relation.
*
* @return array The built meta relation sub-array portion that represents it in WP_Query args.
*/
abstract protected function _buildWpQueryMetaRelation(LogicalExpressionInterface $expression);
/**
* Builds a given logical expression into a WP_Query taxonomy relation array args portion.
*
* @since [*next-version*]
*
* @param LogicalExpressionInterface $expression The expression to build.
*
* @throws OutOfRangeException If the given expression could not be built into a WP_Query taxonomy relation.
*
* @return array The built taxonomy relation sub-array portion that represents it in WP_Query args.
*/
abstract protected function _buildWpQueryTaxRelation(LogicalExpressionInterface $expression);
/**
* Normalizes a value to its string representation.
*
* The values that can be normalized are any scalar values, as well as
* {@see StringableInterface).
*
* @since [*next-version*]
*
* @param string|int|float|bool|Stringable $subject The value to normalize to string.
*
* @throws InvalidArgumentException If the value cannot be normalized.
*
* @return string The string that resulted from normalization.
*/
abstract protected function _normalizeString($subject);
/**
* Creates a new Out Of Range exception.
*
* @since [*next-version*]
*
* @param string|Stringable|null $message The error message, if any.
* @param int|null $code The error code, if any.
* @param RootException|null $previous The inner exception for chaining, if any.
* @param mixed|null $argument The invalid argument, if any.
*
* @return OutOfRangeException The new exception.
*/
abstract protected function _createOutOfRangeException(
$message = null,
$code = null,
RootException $previous = null,
$argument = null
);
/**
* Translates a string, and replaces placeholders.
*
* @since [*next-version*]
* @see sprintf()
*
* @param string $string The format string to translate.
* @param array $args Placeholder values to replace in the string.
* @param mixed $context The context for translation.
*
* @return string The translated string.
*/
abstract protected function __($string, $args = [], $context = null);
}