<?php

namespace App\Http\Controllers\SiteAdmin;

use App\Http\Controllers\Concerns\ResolvesSiteContext;
use App\Http\Controllers\Controller;
use App\Models\Merchant;
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Http\Request;
use Illuminate\View\View;
use Symfony\Component\HttpFoundation\StreamedResponse;

class MerchantController extends Controller
{
    use ResolvesSiteContext;

    public function index(Request $request): View
    {
        $site = $this->site($request);
        $filters = $this->filters($request);

        $query = $this->applySorting(
            $this->applyFilters(
                Merchant::query()
                    ->withCount(['admins', 'users', 'products', 'orders', 'categories'])
                    ->whereKey($site->id),
                $filters
            ),
            $filters
        );

        $merchants = $query->get();
        $summaryStats = $this->buildSummaryStats($site);

        return view('site_admin.merchants.index', [
            'site' => $site,
            'merchants' => $merchants,
            'filters' => $filters,
            'activeFilterSummary' => $this->buildActiveFilterSummary($filters),
            'summaryStats' => $summaryStats,
            'statusLabels' => $this->statusLabels(),
            'planLabels' => $this->planLabels(),
            'filterOptions' => [
                'statuses' => array_keys($this->statusLabels()),
                'plans' => array_keys($this->planLabels()),
                'sortOptions' => [
                    'latest' => '最近激活优先',
                    'name_asc' => '名称 A-Z',
                    'name_desc' => '名称 Z-A',
                ],
            ],
        ]);
    }

    public function export(Request $request): StreamedResponse
    {
        $site = $this->site($request);
        $filters = $this->filters($request);

        $merchants = $this->applySorting(
            $this->applyFilters(
                Merchant::query()
                    ->withCount(['admins', 'users', 'products', 'orders', 'categories'])
                    ->whereKey($site->id),
                $filters
            ),
            $filters
        )->get();

        $summaryStats = $this->buildSummaryStats($site);
        $fileName = 'site_' . $site->id . '_merchants_' . now()->format('Ymd_His') . '.csv';

        return response()->streamDownload(function () use ($site, $filters, $merchants, $summaryStats) {
            $handle = fopen('php://output', 'w');
            fwrite($handle, "\xEF\xBB\xBF");

            fputcsv($handle, ['导出信息', '站点商家导出']);
            fputcsv($handle, ['站点ID', $site->id]);
            fputcsv($handle, ['站点名称', $site->name]);
            fputcsv($handle, ['关键词', ($filters['keyword'] ?? '') !== '' ? $filters['keyword'] : '全部']);
            fputcsv($handle, ['状态', $this->statusLabel($filters['status'] ?? '')]);
            fputcsv($handle, ['套餐', $this->planLabel($filters['plan'] ?? '')]);
            fputcsv($handle, ['排序', $this->sortLabel($filters['sort'] ?? 'latest')]);
            fputcsv($handle, ['承接站点数', $summaryStats['site_count'] ?? 0]);
            fputcsv($handle, ['启用中站点', $summaryStats['active_site_count'] ?? 0]);
            fputcsv($handle, ['站点管理员数', $summaryStats['admin_count'] ?? 0]);
            fputcsv($handle, ['站点用户数', $summaryStats['user_count'] ?? 0]);
            fputcsv($handle, ['站点商品数', $summaryStats['product_count'] ?? 0]);
            fputcsv($handle, ['站点订单数', $summaryStats['order_count'] ?? 0]);
            fputcsv($handle, ['商品分类数', $summaryStats['category_count'] ?? 0]);
            fputcsv($handle, []);

            fputcsv($handle, ['当前站点资料', '']);
            fputcsv($handle, ['站点标识', $site->slug]);
            fputcsv($handle, ['当前状态', $this->statusLabel((string) $site->status)]);
            fputcsv($handle, ['当前套餐', $this->planLabel((string) $site->plan)]);
            fputcsv($handle, ['联系人', $site->contact_name ?: '未设置']);
            fputcsv($handle, ['联系电话', $site->contact_phone ?: '未设置']);
            fputcsv($handle, ['联系邮箱', $site->contact_email ?: '未设置']);
            fputcsv($handle, ['激活时间', $site->activated_at?->format('Y-m-d H:i:s') ?? '未激活']);
            fputcsv($handle, []);

            fputcsv($handle, ['ID', '名称', 'Slug', '状态', '套餐', '联系人', '联系电话', '联系邮箱', '管理员数', '用户数', '商品数', '订单数', '商品分类数', '激活时间']);

            foreach ($merchants as $merchant) {
                fputcsv($handle, [
                    $merchant->id,
                    $merchant->name,
                    $merchant->slug,
                    $this->statusLabel((string) $merchant->status),
                    $this->planLabel((string) $merchant->plan),
                    $merchant->contact_name ?: '未设置',
                    $merchant->contact_phone ?: '未设置',
                    $merchant->contact_email ?: '未设置',
                    $merchant->admins_count ?? 0,
                    $merchant->users_count ?? 0,
                    $merchant->products_count ?? 0,
                    $merchant->orders_count ?? 0,
                    $merchant->categories_count ?? 0,
                    $merchant->activated_at?->format('Y-m-d H:i:s') ?? '未激活',
                ]);
            }

            fclose($handle);
        }, $fileName, [
            'Content-Type' => 'text/csv; charset=UTF-8',
        ]);
    }

    protected function filters(Request $request): array
    {
        return [
            'keyword' => trim((string) $request->string('keyword')),
            'status' => trim((string) $request->string('status')),
            'plan' => trim((string) $request->string('plan')),
            'sort' => trim((string) $request->string('sort', 'latest')),
        ];
    }

    protected function applyFilters(Builder $query, array $filters): Builder
    {
        return $query
            ->when(($filters['status'] ?? '') !== '', fn ($builder) => $builder->where('status', $filters['status']))
            ->when(($filters['plan'] ?? '') !== '', fn ($builder) => $builder->where('plan', $filters['plan']))
            ->when(($filters['keyword'] ?? '') !== '', function ($builder) use ($filters) {
                $keyword = $filters['keyword'];

                $builder->where(function ($subQuery) use ($keyword) {
                    $subQuery->where('name', 'like', '%' . $keyword . '%')
                        ->orWhere('slug', 'like', '%' . $keyword . '%')
                        ->orWhere('contact_name', 'like', '%' . $keyword . '%')
                        ->orWhere('contact_phone', 'like', '%' . $keyword . '%')
                        ->orWhere('contact_email', 'like', '%' . $keyword . '%');
                });
            });
    }

    protected function applySorting(Builder $query, array $filters): Builder
    {
        return match ($filters['sort'] ?? 'latest') {
            'name_asc' => $query->orderBy('name')->orderBy('id'),
            'name_desc' => $query->orderByDesc('name')->orderByDesc('id'),
            default => $query->orderByDesc('activated_at')->orderByDesc('id'),
        };
    }

    protected function buildSummaryStats(Merchant $site): array
    {
        $site->loadCount(['admins', 'users', 'products', 'orders', 'categories']);

        return [
            'site_count' => 1,
            'active_site_count' => $site->status === 'active' ? 1 : 0,
            'admin_count' => (int) ($site->admins_count ?? 0),
            'user_count' => (int) ($site->users_count ?? 0),
            'product_count' => (int) ($site->products_count ?? 0),
            'order_count' => (int) ($site->orders_count ?? 0),
            'category_count' => (int) ($site->categories_count ?? 0),
        ];
    }

    protected function buildActiveFilterSummary(array $filters): array
    {
        return [
            '关键词' => ($filters['keyword'] ?? '') !== '' ? $filters['keyword'] : '全部',
            '状态' => $this->statusLabel($filters['status'] ?? ''),
            '套餐' => $this->planLabel($filters['plan'] ?? ''),
            '排序' => $this->sortLabel($filters['sort'] ?? 'latest'),
        ];
    }

    protected function statusLabels(): array
    {
        return [
            'active' => '启用中',
            'inactive' => '未启用',
            'suspended' => '已停用',
        ];
    }

    protected function statusLabel(string $status): string
    {
        return $this->statusLabels()[$status] ?? '全部';
    }

    protected function planLabels(): array
    {
        return [
            'basic' => '基础版',
            'pro' => '专业版',
            'enterprise' => '企业版',
        ];
    }

    protected function planLabel(string $plan): string
    {
        return $this->planLabels()[$plan] ?? (($plan === '') ? '全部' : $plan);
    }

    protected function sortLabel(string $sort): string
    {
        return match ($sort) {
            'name_asc' => '名称 A-Z',
            'name_desc' => '名称 Z-A',
            default => '最近激活优先',
        };
    }
}