<?php

declare(strict_types=1);

namespace PrettyLinks\GroundLevel\InProductNotifications\Models;

use InvalidArgumentException;
use Stringable;

class Button implements Stringable
{
    /**
     * Button type: Primary.
     */
    public const TYPE_PRIMARY = 'primary';

    /**
     * Button type: Secondary.
     */
    public const TYPE_SECONDARY = 'secondary';

    /**
     * Button type: Link.
     */
    public const TYPE_LINK = 'link';

    /**
     * List of valid button types.
     */
    public const TYPES = [
        self::TYPE_PRIMARY,
        self::TYPE_SECONDARY,
        self::TYPE_LINK,
    ];

    /**
     * Button preset: Dismiss.
     */
    public const PRESET_DISMISS = 'dismiss';

    /**
     * List of valid button presets.
     */
    public const PRESETS = [
        self::PRESET_DISMISS,
    ];

    /**
     * The button label.
     *
     * @var string
     */
    public string $label;

    /**
     * The button URL.
     *
     * @var string
     */
    public string $url;

    /**
     * The button type.
     *
     * @var string
     */
    public string $type;

    /**
     * The button target.
     *
     * @var string|null
     */
    public ?string $target;

    /**
     * Button constructor.
     *
     * @param array $rawData The button data.
     *
     * @throws \InvalidArgumentException When an invalid type or preset is provided or when required data is missing.
     */
    public function __construct(array $rawData)
    {
        if (isset($rawData['preset'])) {
            $rawData = array_merge($this->presetData($rawData['preset']), $rawData);
        }

        $this->type = $rawData['type'] ?? self::TYPE_PRIMARY;
        if (! in_array($this->type, self::TYPES, true)) {
            throw new InvalidArgumentException(
                "Invalid type: {$this->type}. Must be one of: " . implode('|', self::TYPES)
            );
        }

        $this->label = $rawData['label'] ?? '';
        if (empty($this->label)) {
            throw new InvalidArgumentException(
                'Invalid button data: label is required'
            );
        }

        $this->url = $rawData['url'] ?? '';
        if (empty($this->url)) {
            throw new InvalidArgumentException(
                'Invalid button data: url is required'
            );
        }

        $this->target = $rawData['target'] ?? null;
    }

    /**
     * Retrieves the data for a button preset.
     *
     * @param string $preset The preset name.
     *
     * @return array The button data.
     * @throws \InvalidArgumentException When an invalid preset is provided.
     */
    private function presetData(string $preset): array
    {
        switch ($preset) {
            case self::PRESET_DISMISS:
                return [
                    'type'  => self::TYPE_LINK,
                    'url'   => '#notification-dismiss',
                    'label' => __('Dismiss', 'pretty-link'),
                ];
            default:
                throw new InvalidArgumentException(
                    "Invalid preset: {$preset}. Must be one of: " . implode('|', self::PRESETS)
                );
        }
    }

    /**
     * Retrieves the HTML for the button.
     *
     * @return string The HTML for the button.
     */
    public function toHtml(): string
    {
        $attrs = [
            'class' => 'btn btn--' . $this->type,
            'href'  => $this->url,
        ];
        if ($this->target) {
            $attrs['target'] = $this->target;
        }
        $attrs = array_map(
            function (string $key, string $value): string {
                return $key . '="' . esc_attr($value) . '"';
            },
            array_keys($attrs),
            $attrs
        );
        return '<a ' . implode(' ', $attrs) . '>' . esc_html($this->label) . '</a>';
    }

    /**
     * Retrieves the string representation of the button.
     *
     * @return string The string representation of the button.
     */
    public function __toString(): string
    {
        return $this->toHtml();
    }
}
