DataCalculateValue.php

<?php

namespace Drupal\rules\Plugin\RulesAction;

use Drupal\rules\Core\RulesActionBase;

/**
 * Provides a 'numeric calculation' action.
 *
 * @todo Add access callback information from Drupal 7.
 * @todo Add defined operation options from Drupal 7.
 * @todo If context args are integers, ensure that integers are returned.
 *
 * @RulesAction(
 *   id = "rules_data_calculate_value",
 *   label = @Translation("Calculate a numeric value"),
 *   category = @Translation("Data"),
 *   context_definitions = {
 *     "input_1" = @ContextDefinition("float",
 *       label = @Translation("Input value 1"),
 *       description = @Translation("The first input value for the calculation.")
 *     ),
 *     "operator" = @ContextDefinition("string",
 *       label = @Translation("Operator"),
 *       description = @Translation("The calculation operator."),
 *       options_provider = "\Drupal\rules\TypedData\Options\CalculationOperatorOptions",
 *       assignment_restriction = "input"
 *     ),
 *     "input_2" = @ContextDefinition("float",
 *       label = @Translation("Input value 2"),
 *       description = @Translation("The second input value for the calculation.")
 *     ),
 *   },
 *   provides = {
 *     "result" = @ContextDefinition("float",
 *       label = @Translation("Calculated result")
 *     ),
 *   }
 * )
 */
class DataCalculateValue extends RulesActionBase {
    
    /**
     * Executes the action with the given context.
     *
     * @param float $input_1
     *   The first input value.
     * @param string $operator
     *   The operator that should be applied.
     * @param float $input_2
     *   The second input value.
     */
    protected function doExecute($input_1, $operator, $input_2) {
        switch ($operator) {
            case '+':
                $result = $input_1 + $input_2;
                break;
            case '-':
                $result = $input_1 - $input_2;
                break;
            case '*':
                $result = $input_1 * $input_2;
                break;
            case '/':
                $result = $input_1 / $input_2;
                break;
            case 'min':
                $result = min($input_1, $input_2);
                break;
            case 'max':
                $result = max($input_1, $input_2);
                break;
        }
        if (isset($result)) {
            $this->setProvidedValue('result', $result);
        }
    }

}