<?php

declare(strict_types=1);

namespace Sarcio\WordPress\Extension;

use Sarcio\WordPress\Assistant\Ability;

/**
 * What extensions registered through `Api` during this request: their
 * abilities (already wrapped as the plugin's own), the earlier names those
 * answer to, and what shows each one's staged value on the preview.
 *
 * @internal
 */
final class Registry
{
    /** @var array<string,Ability> */
    private static array $abilities = [];
    /** @var array<string,string> alias => current name */
    private static array $aliases = [];
    /** @var array<string,\Closure> ability name => what shows its staged value on the preview */
    private static array $renders = [];

    /** @param array<int,string> $aliases */
    public static function addAbility(Ability $ability, array $aliases, ?\Closure $render = null): bool
    {
        if (isset(self::$abilities[$ability->name]) || isset(self::$aliases[$ability->name])) {
            return false;
        }
        foreach ($aliases as $alias) {
            if (isset(self::$abilities[$alias]) || isset(self::$aliases[$alias])) {
                return false;
            }
        }
        self::$abilities[$ability->name] = $ability;
        if ($render !== null) {
            self::$renders[$ability->name] = $render;
        }
        foreach ($aliases as $alias) {
            self::$aliases[$alias] = $ability->name;
        }
        return true;
    }

    /** @return array<int,Ability> */
    public static function abilities(): array
    {
        return array_values(self::$abilities);
    }

    /** The current name an earlier ability name now answers to, if any. */
    public static function aliasFor(string $name): ?string
    {
        return self::$aliases[$name] ?? null;
    }

    /**
     * Hands each extension ability what it staged on the preview being shown.
     * A render that fails leaves the page as WordPress holds it.
     *
     * @param array<string,mixed> $staged ability name => staged value
     */
    public static function render(array $staged): void
    {
        foreach ($staged as $name => $value) {
            $render = self::$renders[$name] ?? self::$renders[self::$aliases[$name] ?? ''] ?? null;
            if ($render === null) {
                continue;
            }
            try {
                $render($value);
            } catch (\Throwable) {
                continue;
            }
        }
    }

    public static function reset(): void
    {
        self::$abilities = [];
        self::$aliases = [];
        self::$renders = [];
    }
}