<?php

namespace App\Http\Controllers\Admin;

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

class SiteSubscriptionController extends Controller
{
    use ResolvesPlatformAdminContext;

    public function export(Request $request): StreamedResponse
    {
        $this->ensurePlatformAdmin($request);

        $filters = [
            'status' => trim((string) $request->query('status', '')),
            'keyword' => trim((string) $request->query('keyword', '')),
            'merchant_id' => trim((string) $request->query('merchant_id', '')),
            'plan_id' => trim((string) $request->query('plan_id', '')),
            'expiry' => trim((string) $request->query('expiry', '')),
        ];

        $query = $this->applyFilters(
            SiteSubscription::query()->with(['merchant', 'plan'])->withCount('platformOrders'),
            $filters
        )->orderBy('id');

        $filename = 'site_subscriptions_' . now()->format('Ymd_His') . '.csv';

        return response()->streamDownload(function () use ($query) {
            $out = fopen('php://output', 'w');

            // UTF-8 BOM，避免 Excel 打开中文乱码
            fwrite($out, "\xEF\xBB\xBF");

            fputcsv($out, [
                'ID',
                '订阅号',
                '站点',
                '套餐',
                '关联订单数',
                '状态',
                '计费周期',
                '周期(月)',
                '金额',
                '开始时间',
                '到期时间',
                '到期状态',
                '试用到期',
                '生效时间',
                '取消时间',
            ]);

            $statusLabels = $this->statusLabels();

            $query->chunkById(500, function ($subs) use ($out, $statusLabels) {
                foreach ($subs as $sub) {
                    $endsAt = $sub->ends_at;
                    $expiryLabel = '无到期';
                    if ($endsAt) {
                        if ($endsAt->lt(now())) {
                            $expiryLabel = '已过期';
                        } elseif ($endsAt->lt(now()->addDays(7))) {
                            $expiryLabel = '7天内到期';
                        } else {
                            $expiryLabel = '未到期';
                        }
                    }

                    $status = (string) ($sub->status ?? '');
                    $statusText = ($statusLabels[$status] ?? $status);
                    $statusText = $statusText . ' (' . $status . ')';

                    fputcsv($out, [
                        $sub->id,
                        $sub->subscription_no,
                        $sub->merchant?->name ?? '',
                        $sub->plan_name ?: ($sub->plan?->name ?? ''),
                        (int) ($sub->platform_orders_count ?? 0),
                        $statusText,
                        $sub->billing_cycle ?: '',
                        (int) $sub->period_months,
                        (float) $sub->amount,
                        optional($sub->starts_at)->format('Y-m-d H:i:s') ?: '',
                        optional($sub->ends_at)->format('Y-m-d H:i:s') ?: '',
                        $expiryLabel,
                        optional($sub->trial_ends_at)->format('Y-m-d H:i:s') ?: '',
                        optional($sub->activated_at)->format('Y-m-d H:i:s') ?: '',
                        optional($sub->cancelled_at)->format('Y-m-d H:i:s') ?: '',
                    ]);
                }
            });

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

    public function index(Request $request): View
    { 
        $this->ensurePlatformAdmin($request);

        $filters = [
            'status' => trim((string) $request->query('status', '')),
            'keyword' => trim((string) $request->query('keyword', '')),
            'merchant_id' => trim((string) $request->query('merchant_id', '')),
            'plan_id' => trim((string) $request->query('plan_id', '')),
            // 到期辅助筛选（不改变 status 字段，仅按 ends_at 计算）
            // - expired：已过期（ends_at < now）
            // - expiring_7d：7 天内到期（now <= ends_at < now+7d）
            'expiry' => trim((string) $request->query('expiry', '')),
        ];

        $query = $this->applyFilters(
            SiteSubscription::query()->with(['merchant', 'plan'])->withCount('platformOrders'),
            $filters
        );

        $subscriptions = (clone $query)
            ->latest('id')
            ->paginate(10)
            ->withQueryString();

        $baseQuery = $this->applyFilters(SiteSubscription::query(), $filters);

        return view('admin.site_subscriptions.index', [
            'subscriptions' => $subscriptions,
            'filters' => $filters,
            'statusLabels' => $this->statusLabels(),
            'filterOptions' => [
                'statuses' => $this->statusLabels(),
            ],
            'merchants' => SiteSubscription::query()->with('merchant')->select('merchant_id')->distinct()->get()->pluck('merchant')->filter()->unique('id')->values(),
            'plans' => SiteSubscription::query()->with('plan')->select('plan_id')->whereNotNull('plan_id')->distinct()->get()->pluck('plan')->filter()->unique('id')->values(),
            'summaryStats' => [
                'total_subscriptions' => (clone $baseQuery)->count(),
                'activated_subscriptions' => (clone $baseQuery)->where('status', 'activated')->count(),
                'pending_subscriptions' => (clone $baseQuery)->where('status', 'pending')->count(),
                'cancelled_subscriptions' => (clone $baseQuery)->where('status', 'cancelled')->count(),
                // 可治理辅助指标：按 ends_at 计算
                'expired_subscriptions' => (clone $baseQuery)
                    ->whereNotNull('ends_at')
                    ->where('ends_at', '<', now())
                    ->count(),
                'expiring_7d_subscriptions' => (clone $baseQuery)
                    ->whereNotNull('ends_at')
                    ->where('ends_at', '>=', now())
                    ->where('ends_at', '<', now()->addDays(7))
                    ->count(),
            ],
        ]);
    }

    protected function statusLabels(): array
    {
        return [
            'pending' => '待生效',
            'activated' => '已生效',
            'cancelled' => '已取消',
            'expired' => '已过期',
        ];
    }

    protected function applyFilters(Builder $query, array $filters): Builder
    {
        return $query
            ->when($filters['status'] !== '', fn (Builder $builder) => $builder->where('status', $filters['status']))
            ->when(($filters['merchant_id'] ?? '') !== '', fn (Builder $builder) => $builder->where('merchant_id', (int) $filters['merchant_id']))
            ->when(($filters['plan_id'] ?? '') !== '', fn (Builder $builder) => $builder->where('plan_id', (int) $filters['plan_id']))
            ->when(($filters['expiry'] ?? '') !== '', function (Builder $builder) use ($filters) {
                $expiry = (string) ($filters['expiry'] ?? '');
                if ($expiry === 'expired') {
                    $builder->whereNotNull('ends_at')->where('ends_at', '<', now());
                } elseif ($expiry === 'expiring_7d') {
                    $builder->whereNotNull('ends_at')
                        ->where('ends_at', '>=', now())
                        ->where('ends_at', '<', now()->addDays(7));
                }
            })
            ->when($filters['keyword'] !== '', function (Builder $builder) use ($filters) {
                // 关键词搜索：订阅号 / 站点 / 套餐 / 计费周期
                $keyword = trim((string) ($filters['keyword'] ?? ''));
                if ($keyword === '') {
                    return;
                }

                $builder->where(function (Builder $q) use ($keyword) {
                    $q->where('subscription_no', 'like', '%' . $keyword . '%')
                        ->orWhere('plan_name', 'like', '%' . $keyword . '%')
                        ->orWhere('billing_cycle', 'like', '%' . $keyword . '%')
                        ->orWhereHas('merchant', function (Builder $mq) use ($keyword) {
                            $mq->where('name', 'like', '%' . $keyword . '%')
                                ->orWhere('slug', 'like', '%' . $keyword . '%');
                        })
                        ->orWhereHas('plan', function (Builder $pq) use ($keyword) {
                            $pq->where('name', 'like', '%' . $keyword . '%')
                                ->orWhere('code', 'like', '%' . $keyword . '%');
                        });

                    if (ctype_digit($keyword)) {
                        $q->orWhere('id', (int) $keyword);
                    }
                });
            });
    }
}