<?php

declare(strict_types=1);

namespace App\Http\Controllers\Admin;

use App\Http\Controllers\Controller;
use App\Models\HomeModule;
use App\Models\HomeModuleItem;
use Illuminate\Contracts\View\View;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Cache;
use Illuminate\Validation\Rule;

class SiteSettingController extends Controller
{
    public function index(): View
    {
        $modules = HomeModule::query()
            ->with(['items' => fn ($query) => $query->orderBy('sort_order')->orderBy('id')])
            ->orderBy('sort_order')
            ->orderBy('id')
            ->get();

        if ($modules->isEmpty()) {
            $this->ensureDefaultModules();

            $modules = HomeModule::query()
                ->with(['items' => fn ($query) => $query->orderBy('sort_order')->orderBy('id')])
                ->orderBy('sort_order')
                ->orderBy('id')
                ->get();
        }

        return view('admin.settings.index', [
            'modules' => $modules,
            'routeOptions' => $this->routeOptions(),
        ]);
    }

    public function update(Request $request): RedirectResponse
    {
        $moduleData = $request->input('modules', []);
        if (!is_array($moduleData) || $moduleData === []) {
            return redirect()
                ->route('admin.settings.index')
                ->with('status', '未提交有效的模块配置。');
        }

        foreach ($moduleData as $moduleId => $moduleInput) {
            if (!is_numeric($moduleId) || !is_array($moduleInput)) {
                continue;
            }

            $module = HomeModule::query()->find((int) $moduleId);
            if (! $module instanceof HomeModule) {
                continue;
            }

            $validatedModule = validator($moduleInput, [
                'name' => ['required', 'string', 'max:120'],
                'title' => ['nullable', 'string', 'max:160'],
                'subtitle' => ['nullable', 'string', 'max:255'],
                'enabled' => ['nullable', 'boolean'],
                'sort_order' => ['nullable', 'integer', 'min:0', 'max:9999'],
                'limit' => ['nullable', 'integer', 'min:1', 'max:30'],
                'more_link_type' => ['nullable', Rule::in(['route', 'url'])],
                'more_link_target' => ['nullable', 'string', 'max:255'],
                'extra.side_title' => ['nullable', 'string', 'max:120'],
                'extra.side_subtitle' => ['nullable', 'string', 'max:255'],
            ])->validate();

            $module->fill([
                'name' => $validatedModule['name'],
                'title' => $validatedModule['title'] ?? null,
                'subtitle' => $validatedModule['subtitle'] ?? null,
                'enabled' => (bool) ($validatedModule['enabled'] ?? false),
                'sort_order' => (int) ($validatedModule['sort_order'] ?? $module->sort_order),
                'limit' => (int) ($validatedModule['limit'] ?? $module->limit),
                'more_link_type' => $validatedModule['more_link_type'] ?? null,
                'more_link_target' => $validatedModule['more_link_target'] ?? null,
                'extra' => [
                    'side_title' => data_get($validatedModule, 'extra.side_title'),
                    'side_subtitle' => data_get($validatedModule, 'extra.side_subtitle'),
                ],
            ]);

            $this->validateModuleLink($module->module_key, $module->more_link_type, $module->more_link_target);
            $module->save();

            $itemsInput = $moduleInput['items'] ?? [];
            if (!is_array($itemsInput)) {
                continue;
            }

            foreach ($itemsInput as $itemId => $itemInput) {
                if (!is_numeric($itemId) || !is_array($itemInput)) {
                    continue;
                }

                $item = HomeModuleItem::query()
                    ->where('home_module_id', $module->id)
                    ->find((int) $itemId);

                if (! $item instanceof HomeModuleItem) {
                    continue;
                }

                $validatedItem = validator($itemInput, [
                    'title' => ['nullable', 'string', 'max:160'],
                    'subtitle' => ['nullable', 'string', 'max:255'],
                    'image_path' => ['nullable', 'string', 'max:255'],
                    'link_type' => ['nullable', Rule::in(['route', 'url'])],
                    'link_target' => ['nullable', 'string', 'max:255'],
                    'sort_order' => ['nullable', 'integer', 'min:0', 'max:9999'],
                    'enabled' => ['nullable', 'boolean'],
                ])->validate();

                $linkType = $validatedItem['link_type'] ?? 'route';
                $linkTarget = $validatedItem['link_target'] ?? null;

                $this->validateItemRules($module->module_key, $validatedItem);
                $this->validateItemLink($linkType, $linkTarget);

                $item->fill([
                    'title' => $validatedItem['title'] ?? null,
                    'subtitle' => $validatedItem['subtitle'] ?? null,
                    'image_path' => $validatedItem['image_path'] ?? null,
                    'link_type' => $linkType,
                    'link_target' => $linkTarget,
                    'sort_order' => (int) ($validatedItem['sort_order'] ?? $item->sort_order),
                    'enabled' => (bool) ($validatedItem['enabled'] ?? false),
                ])->save();
            }
        }

        $this->clearHomeCaches();

        return redirect()
            ->route('admin.settings.index')
            ->with('status', '首页模块配置已更新。');
    }

    public function storeItem(Request $request, HomeModule $module): RedirectResponse
    {
        $validated = $request->validate([
            'title' => ['nullable', 'string', 'max:160'],
            'subtitle' => ['nullable', 'string', 'max:255'],
            'image_path' => ['nullable', 'string', 'max:255'],
            'link_type' => ['required', Rule::in(['route', 'url'])],
            'link_target' => ['nullable', 'string', 'max:255'],
            'sort_order' => ['nullable', 'integer', 'min:0', 'max:9999'],
            'enabled' => ['nullable', 'boolean'],
        ]);

        $this->validateItemRules($module->module_key, $validated);
        $this->validateItemLink($validated['link_type'], $validated['link_target'] ?? null);

        $module->items()->create([
            'title' => $validated['title'] ?? null,
            'subtitle' => $validated['subtitle'] ?? null,
            'image_path' => $validated['image_path'] ?? null,
            'link_type' => $validated['link_type'],
            'link_target' => $validated['link_target'] ?? null,
            'sort_order' => (int) ($validated['sort_order'] ?? (($module->items()->max('sort_order') ?? 0) + 10)),
            'enabled' => (bool) ($validated['enabled'] ?? true),
        ]);

        $this->clearHomeCaches();

        return redirect()
            ->route('admin.settings.index')
            ->with('status', '模块条目已新增。');
    }

    public function destroyItem(HomeModule $module, HomeModuleItem $item): RedirectResponse
    {
        if ($item->home_module_id !== $module->id) {
            abort(404);
        }

        $item->delete();
        $this->clearHomeCaches();

        return redirect()
            ->route('admin.settings.index')
            ->with('status', '模块条目已删除。');
    }

    /**
     * @return array<int, array{name:string,value:string}>
     */
    private function routeOptions(): array
    {
        return [
            ['name' => '工具集首页', 'value' => 'tools.index'],
            ['name' => '工具列表页', 'value' => 'tools.list'],
            ['name' => '模型推荐', 'value' => 'models.index'],
            ['name' => '文章资讯', 'value' => 'news.index'],
            ['name' => '教程学习', 'value' => 'guides.index'],
        ];
    }

    private function ensureDefaultModules(): void
    {
        $defaults = [
            ['key' => 'channel_cards', 'name' => '频道卡片', 'title' => '频道入口', 'sort' => 20, 'limit' => 5],
            ['key' => 'promo_banners', 'name' => '横幅推荐', 'title' => '横幅推荐', 'sort' => 30, 'limit' => 2],
            ['key' => 'hot_tools', 'name' => '热门工具', 'title' => '热门工具', 'sort' => 40, 'limit' => 18],
            ['key' => 'latest_tools', 'name' => '最新收录', 'title' => '最新收录', 'sort' => 50, 'limit' => 18],
            ['key' => 'category_sections', 'name' => '分类分块', 'title' => '分类分块', 'sort' => 60, 'limit' => 18],
        ];

        foreach ($defaults as $default) {
            HomeModule::query()->firstOrCreate([
                'module_key' => $default['key'],
            ], [
                'name' => $default['name'],
                'title' => $default['title'],
                'enabled' => true,
                'sort_order' => $default['sort'],
                'limit' => $default['limit'],
            ]);
        }
    }

    private function validateModuleLink(string $moduleKey, ?string $type, ?string $target): void
    {
        if (!in_array($moduleKey, ['hot_tools', 'latest_tools', 'category_sections'], true)) {
            return;
        }

        if ($type === null && $target === null) {
            return;
        }

        if ($type === 'route') {
            if (! in_array($target, array_column($this->routeOptions(), 'value'), true)) {
                abort(422, '模块“更多链接”路由不在允许范围内。');
            }

            return;
        }

        if ($type === 'url' && $target !== null && ! $this->isValidUrlOrPath($target)) {
            abort(422, '模块“更多链接”URL格式不正确。');
        }
    }

    private function validateItemRules(string $moduleKey, array $item): void
    {
        if (! in_array($moduleKey, ['channel_cards', 'promo_banners'], true)) {
            return;
        }

        $title = trim((string) ($item['title'] ?? ''));
        $imagePath = trim((string) ($item['image_path'] ?? ''));
        $linkTarget = trim((string) ($item['link_target'] ?? ''));

        if ($title === '' || $imagePath === '' || $linkTarget === '') {
            abort(422, '频道卡片/横幅推荐条目必须填写标题、图片、链接。');
        }
    }

    private function validateItemLink(string $type, ?string $target): void
    {
        if ($type === 'route') {
            if (! in_array((string) $target, array_column($this->routeOptions(), 'value'), true)) {
                abort(422, '条目路由不在允许范围内。');
            }

            return;
        }

        if ($target === null || ! $this->isValidUrlOrPath($target)) {
            abort(422, '条目URL格式不正确。');
        }
    }

    private function isValidUrlOrPath(string $value): bool
    {
        if (str_starts_with($value, '/')) {
            return true;
        }

        return (bool) filter_var($value, FILTER_VALIDATE_URL);
    }

    private function clearHomeCaches(): void
    {
        Cache::flush();
    }
}