<?php
/**
 * Handles adding and dispatching events
 *
 * @package Requests\EventDispatcher
 */

namespace WpOrg\Requests;

use WpOrg\Requests\Exception\InvalidArgument;
use WpOrg\Requests\HookManager;
use WpOrg\Requests\Utility\InputValidator;

/**
 * Handles adding and dispatching events
 *
 * @package Requests\EventDispatcher
 */
class Hooks implements HookManager {
    /**
     * Registered callbacks for each hook
     *
     * @var array
     */
    protected $hooks = [];

    /**
     * Register a callback for a hook
     *
     * @param string $hook Hook name
     * @param callable $callback Function/method to call on event
     * @param int $priority Priority number. <0 is executed earlier, >0 is executed later
     * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $hook argument is not a string.
     * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $callback argument is not callable.
     * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $priority argument is not an integer.
     */
    public function register($hook, $callback, $priority = 0) {
        if (is_string($hook) === false) {
            throw InvalidArgument::create(1, '$hook', 'string', gettype($hook));
        }

        if (is_callable($callback) === false) {
            throw InvalidArgument::create(2, '$callback', 'callable', gettype($callback));
        }

        if (InputValidator::is_numeric_array_key($priority) === false) {
            throw InvalidArgument::create(3, '$priority', 'integer', gettype($priority));
        }

        if (!isset($this->hooks[$hook])) {
            $this->hooks[$hook] = [
                $priority => [],
            ];
        } elseif (!isset($this->hooks[$hook][$priority])) {
            $this->hooks[$hook][$priority] = [];
        }

        $this->hooks[$hook][$priority][] = $callback;
    }

    /**
     * Dispatch a message
     *
     * @param string $hook Hook name
     * @param array $parameters Parameters to pass to callbacks
     * @return boolean Successfulness
     * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $hook argument is not a string.
     * @throws \WpOrg\Requests\Exception\InvalidArgument When the passed $parameters argument is not an array.
     */
    public function dispatch($hook, $parameters = []) {
        if (is_string($hook) === false) {
            throw InvalidArgument::create(1, '$hook', 'string', gettype($hook));
        }

        // Check strictly against array, as Array* objects don't work in combination with `call_user_func_array()`.
        if (is_array($parameters) === false) {
            throw InvalidArgument::create(2, '$parameters', 'array', gettype($parameters));
        }

        if (empty($this->hooks[$hook])) {
            return false;
        }

        if (!empty($parameters)) {
            // Strip potential keys from the array to prevent them being interpreted as parameter names in PHP 8.0.
            $parameters = array_values($parameters);
        }

        ksort($this->hooks[$hook]);

        foreach ($this->hooks[$hook] as $priority => $hooked) {
            foreach ($hooked as $callback) {
                $callback(...$parameters);
            }
        }

        return true;
    }
}