bowler/src/app/Models/Theme.php

<?php

namespace App\Models;

use App\Enums\NavGradientDirection;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Support\Facades\Cache;

class Theme extends Model
{
    protected $table = 'site_themes';

    protected $guarded = ['id'];

    protected $casts = [
        'nav_gradient_direction' => NavGradientDirection::class,
    ];

    /** Stock values — must match the migration defaults and the @theme tokens in app.css. */
    public const DEFAULTS = [
        'primary_color' => '#2563eb',
        'secondary_color' => '#3b82f6',
        'tertiary_color' => '#1d4ed8',
        'nav_gradient_from' => '#ffffff',
        'nav_gradient_mid' => null,
        'nav_gradient_to' => null,
        'nav_gradient_direction' => 'none',
    ];

    protected static function booted(): void
    {
        static::saved(fn () => Cache::forget('site-theme'));
        static::deleted(fn () => Cache::forget('site-theme'));
    }

    /** The single site-wide theme row, cached until the next save. */
    public static function current(): self
    {
        // refresh() hydrates the DB column defaults into the fresh model.
        return Cache::rememberForever(
            'site-theme',
            fn () => static::query()->first() ?? static::query()->create([])->refresh()
        );
    }

    /** True when the theme matches the stock look exactly (no override needed). */
    public function isDefault(): bool
    {
        if ($this->logo_path !== null) {
            return false;
        }

        foreach (self::DEFAULTS as $key => $default) {
            $value = $this->{$key};
            if ($value instanceof \BackedEnum) {
                $value = $value->value;
            }

            if ($value === null || $default === null) {
                if ($value !== $default) {
                    return false;
                }
                continue;
            }

            if (strtolower((string) $value) !== strtolower((string) $default)) {
                return false;
            }
        }

        return true;
    }

    public function primaryHover(): string
    {
        return self::darken($this->primary_color, 0.15);
    }

    /** CSS background value for the top bar: solid color or gradient. */
    public function navBackgroundCss(): string
    {
        $stops = $this->activeGradientStops();

        if ($this->nav_gradient_direction === NavGradientDirection::None || count($stops) < 2) {
            return $this->nav_gradient_from;
        }

        $list = implode(', ', $stops);

        return $this->nav_gradient_direction === NavGradientDirection::Radial
            ? "radial-gradient(ellipse at top, {$list})"
            : "linear-gradient({$this->nav_gradient_direction->cssKeyword()}, {$list})";
    }

    /** Whether the nav background is dark enough to need white text (WCAG contrast). */
    public function navIsDark(): bool
    {
        $stops = $this->nav_gradient_direction === NavGradientDirection::None
            ? [$this->nav_gradient_from]
            : $this->activeGradientStops();

        $l = array_sum(array_map(self::luminance(...), $stops)) / count($stops);

        // White text wins when its contrast beats gray-900's (luminance ~0.0106).
        return (1.05 / ($l + 0.05)) >= (($l + 0.05) / 0.0606);
    }

    public function navLinkColor(): string
    {
        return $this->navIsDark() ? '#ffffff' : $this->primary_color;
    }

    public function navTextColor(): string
    {
        return $this->navIsDark() ? '#ffffff' : '#111827';
    }

    public function navMutedColor(): string
    {
        return $this->navIsDark() ? 'rgba(255, 255, 255, 0.75)' : '#6b7280';
    }

    /** @return list<string> */
    private function activeGradientStops(): array
    {
        return array_values(array_filter([
            $this->nav_gradient_from,
            $this->nav_gradient_mid,
            $this->nav_gradient_to,
        ]));
    }

    /** WCAG relative luminance of a #rrggbb color. */
    private static function luminance(string $hex): float
    {
        [$r, $g, $b] = sscanf($hex, '#%02x%02x%02x');

        $lin = function (int $c): float {
            $c = $c / 255;

            return $c <= 0.03928 ? $c / 12.92 : (($c + 0.055) / 1.055) ** 2.4;
        };

        return 0.2126 * $lin($r) + 0.7152 * $lin($g) + 0.0722 * $lin($b);
    }

    private static function darken(string $hex, float $amount): string
    {
        [$r, $g, $b] = sscanf($hex, '#%02x%02x%02x');

        return sprintf(
            '#%02x%02x%02x',
            (int) round($r * (1 - $amount)),
            (int) round($g * (1 - $amount)),
            (int) round($b * (1 - $amount))
        );
    }
}