<?php

declare(strict_types=1);

namespace App\Libraries;

use App\Models\CategoryModel;
use App\Models\ToolModel;

/**
 * Request-cached accessor for the tool registry. Every page, sitemap,
 * route and link block goes through here so the DB is hit at most once
 * per dataset per request.
 */
final class Finder
{
    private ?array $bySlug = null;

    /** @var array<int,array>|null */
    private ?array $categories = null;

    public function tool(string $slug): ?array
    {
        if ($this->bySlug === null) {
            $tools       = model(ToolModel::class)->allActive();
            $this->bySlug = [];
            foreach ($tools as $tool) {
                // decode JSON columns once per request
                foreach (['input_formats', 'output_formats', 'how_to', 'faqs', 'related_slugs', 'aliases', 'requires_binaries', 'accepts_mimes'] as $col) {
                    if (isset($tool[$col]) && is_string($tool[$col])) {
                        $decoded = json_decode($tool[$col], true);
                        $tool[$col] = is_array($decoded) ? $decoded : [];
                    } elseif (! isset($tool[$col])) {
                        $tool[$col] = [];
                    }
                }
                $this->bySlug[$tool['slug']] = $tool;
            }
        }

        return $this->bySlug[mb_strtolower($slug)] ?? null;
    }

    public function categories(): array
    {
        if ($this->categories === null) {
            $this->categories = model(CategoryModel::class)->activeOrdered();
        }

        return $this->categories;
    }

    public function category(string $slug): ?array
    {
        foreach ($this->categories() as $category) {
            if ($category['slug'] === $slug) {
                foreach (['faqs'] as $col) {
                    if (isset($category[$col]) && is_string($category[$col])) {
                        $decoded              = json_decode($category[$col], true);
                        $category[$col] = is_array($decoded) ? $decoded : [];
                    }
                }

                return $category;
            }
        }

        return null;
    }

    public function categoryById(int $id): ?array
    {
        foreach ($this->categories() as $category) {
            if ((int) $category['id'] === $id) {
                return $category;
            }
        }

        return null;
    }

    public function toolsInCategory(string $slug): array
    {
        $category = $this->category($slug);
        if ($category === null) {
            return [];
        }
        $tools = model(ToolModel::class)->activeInCategory((int) $category['id']);
        foreach ($tools as &$t) {
            $this->decodeTool($t);
        }

        return $tools;
    }

    public function popular(int $limit = 8): array
    {
        $tools = model(ToolModel::class)->popular($limit);
        array_walk($tools, [$this, 'decodeTool']);

        return $tools;
    }

    public function featured(int $limit = 8): array
    {
        $tools = model(ToolModel::class)->featured($limit);
        array_walk($tools, [$this, 'decodeTool']);

        return $tools;
    }

    public function recent(int $limit = 6): array
    {
        $tools = model(ToolModel::class)->recent($limit);
        array_walk($tools, [$this, 'decodeTool']);

        return $tools;
    }

    public function all(): array
    {
        return array_values($this->index());
    }

    public function countTools(): int
    {
        return count($this->index());
    }

    private function index(): array
    {
        if ($this->bySlug === null) {
            $this->tool('__warm__'); // forces load
        }

        return $this->bySlug ?? [];
    }

    public static function decodeTool(array &$tool): void
    {
        foreach (['input_formats', 'output_formats', 'how_to', 'faqs', 'related_slugs', 'aliases', 'requires_binaries', 'accepts_mimes'] as $col) {
            if (isset($tool[$col]) && is_string($tool[$col])) {
                $decoded     = json_decode($tool[$col], true);
                $tool[$col] = is_array($decoded) ? $decoded : [];
            } elseif (! isset($tool[$col])) {
                $tool[$col] = [];
            }
        }
    }
}