<?php

namespace App\Http\Controllers\Api\Service;

use App\Http\Controllers\Controller;
use App\Http\Controllers\Api\Service\Concerns\ResolvesVm;
use App\Http\Services\vCenter;
use App\Jobs\VirtualMachine\Snapshot\CreateSnapshot;
use App\Jobs\VirtualMachine\Snapshot\RevertSnapshot;
use App\Jobs\VirtualMachine\Snapshot\RemoveSnapshot;
use App\Models\ModuleSnapshot;
use App\Models\ModuleVmware;
use App\Services\ActivityLogger;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;

class SnapshotController extends Controller
{
    use ResolvesVm;

    public function __construct(protected ActivityLogger $activityLogger) {}

    public function store(Request $request): JsonResponse
    {
        $customer = $request->user();
        $payload = $request->validate([
            'product' => ['required'],
            'description' => ['nullable', 'string', 'max:1000'],
            'name' => ['nullable', 'string', 'max:80', 'regex:/^[A-Za-z0-9._-]+$/'],
        ], [
            'name.regex' => 'Tên snapshot chỉ gồm chữ không dấu, số và các ký tự . _ -',
            'name.max' => 'Tên snapshot tối đa 80 ký tự.',
        ]);

        $vm = $this->resolveVmById($payload['product'], $request);
        if ($vm instanceof JsonResponse) {
            return $vm;
        }

        $snapshotName = $payload['name'] ?? $this->suggestName($vm);
        if (ModuleSnapshot::where('module_vmware_id', $vm->id)->where('name', $snapshotName)->exists()) {
            return response()->json(['error' => true, 'message' => 'Tên snapshot đã tồn tại, vui lòng chọn tên khác.'], 422);
        }

        $snapshot = ModuleSnapshot::create([
            'name'             => $snapshotName,
            'description'      => $payload['description'] ?? null,
            'customer_id'      => $customer->id,
            'module_vmware_id' => $vm->id,
            'status'           => 'pending',
            'snapshot_ref'     => null,
        ]);

        CreateSnapshot::dispatch($snapshot->id);

        $this->activityLogger->log(
            event: 'created',
            logName: 'Snapshot',
            description: "Customer {$customer->email} tạo snapshot: {$snapshot->name} cho VM #{$vm->id}",
            subject: $snapshot,
            newValues: ['name' => $snapshot->name, 'vm_id' => $vm->id],
        );

        return response()->json([
            'error' => false,
            'message' => 'Đã gửi yêu cầu tạo snapshot vào hàng đợi',
            'data' => [
                'id'          => $snapshot->id,
                'name'        => $snapshot->name,
                'description' => $snapshot->description,
                'status'      => 'pending',
            ],
        ]);
    }

    private function suggestName(ModuleVmware $vm): string
    {
        $prefix = sprintf('%s-%s-', $vm->name, now()->format('d-m-Y'));
        $sequence = ModuleSnapshot::where('module_vmware_id', $vm->id)->whereDate('created_at', today())->count() + 1;

        while (ModuleSnapshot::where('module_vmware_id', $vm->id)->where('name', $prefix . $sequence)->exists()) {
            $sequence++;
        }

        return $prefix . $sequence;
    }

    public function index(Request $request, vCenter $serviceVCenter): JsonResponse
    {
        $productParam = $request->query('product');
        if (!$productParam) {
            return response()->json(['error' => true, 'message' => 'Thiếu product id'], 422);
        }

        $vm = $this->resolveVmById($productParam, $request, requireActiveService: false);
        if ($vm instanceof JsonResponse) {
            return $vm;
        }

        $remote = $serviceVCenter->getSnapShot($vm);
        if (is_string($remote) || ($remote['error'] ?? true)) {
            return response()->json([
                'error' => true,
                'message' => is_string($remote) ? $remote : ($remote['message'] ?? 'Không thể lấy danh sách snapshot'),
            ], 400);
        }

        $remoteItems = $remote['data'] ?? [];
        foreach ($remoteItems as $item) {
            $ref = (string) ($item['id'] ?? $item['name'] ?? '');
            $name = (string) ($item['name'] ?? $ref);
            if ($name === '') {
                continue;
            }

            $snapshot = ModuleSnapshot::query()
                ->where('module_vmware_id', $vm->id)
                ->where(function ($q) use ($ref, $name) {
                    $q->where('snapshot_ref', $ref)->orWhere('name', $name);
                })
                ->first();

            $payload = [
                'name' => $name,
                'description' => $item['description'] ?? null,
                'customer_id' => $request->user()->id,
                'module_vmware_id' => $vm->id,
                'status' => 'success',
                'snapshot_ref' => $ref ?: $name,
                'size_gb' => isset($item['size_gb']) ? (float) $item['size_gb'] : null,
                'size_last_synced_at' => now(),
            ];

            if ($snapshot) {
                if ($snapshot->status === 'deleting') {
                    unset($payload['status']);
                }
                $snapshot->update($payload);
            } else {
                ModuleSnapshot::create($payload);
            }
        }

        $dbSnapshots = ModuleSnapshot::query()
            ->where('module_vmware_id', $vm->id)
            ->where('customer_id', $request->user()->id)
            ->orderByDesc('created_at')
            ->get()
            ->map(function ($snap) {
                return [
                    'id' => $snap->id,
                    'name' => $snap->name,
                    'description' => $snap->description,
                    'snapshot_ref' => $snap->snapshot_ref,
                    'status' => $snap->status,
                    'size_gb' => $snap->size_gb,
                    'created_at' => $snap->created_at?->toISOString(),
                ];
            });

        return response()->json([
            'error' => false,
            'data' => $dbSnapshots,
            'suggested_name' => $this->suggestName($vm),
        ]);
    }

    public function revert(Request $request): JsonResponse
    {
        $customer = $request->user();
        $payload = $request->validate([
            'product' => ['required'],
            'snapshot_id' => ['required', 'numeric'],
        ]);

        $vm = $this->resolveVmById($payload['product'], $request);
        if ($vm instanceof JsonResponse) {
            return $vm;
        }

        $snapshot = ModuleSnapshot::where('id', $payload['snapshot_id'])
            ->where('module_vmware_id', $vm->id)
            ->where('customer_id', $customer->id)
            ->first();

        if (!$snapshot) {
            return response()->json(['error' => true, 'message' => 'Không tìm thấy snapshot'], 404);
        }

        RevertSnapshot::dispatch($vm->id, $snapshot->id);

        $this->activityLogger->log(
            event: 'revert',
            logName: 'Snapshot',
            description: "Customer {$customer->email} revert snapshot: {$snapshot->name} (ID: {$snapshot->id}) cho VM #{$vm->id}",
            subject: $snapshot,
        );

        return response()->json([
            'error' => false,
            'message' => 'Đã gửi yêu cầu revert snapshot vào hàng đợi',
        ]);
    }

    public function destroy(Request $request): JsonResponse
    {
        $customer = $request->user();
        $payload = $request->validate([
            'product' => ['required'],
            'snapshot_id' => ['required', 'numeric'],
        ]);

        $vm = $this->resolveVmById($payload['product'], $request);
        if ($vm instanceof JsonResponse) {
            return $vm;
        }

        $snapshot = ModuleSnapshot::where('id', $payload['snapshot_id'])
            ->where('module_vmware_id', $vm->id)
            ->where('customer_id', $customer->id)
            ->first();

        if (!$snapshot) {
            return response()->json(['error' => true, 'message' => 'Không tìm thấy snapshot'], 404);
        }

        if ($snapshot->status === 'deleting') {
            return response()->json(['error' => true, 'message' => 'Snapshot đang được xóa.'], 422);
        }

        $deletedNow = $snapshot->status === 'failed';
        if ($deletedNow) {
            $snapshot->delete();
        } else {
            $snapshot->update(['status' => 'deleting']);
            RemoveSnapshot::dispatch($vm->id, $snapshot->id);
        }

        $this->activityLogger->log(
            event: 'deleted',
            logName: 'Snapshot',
            description: "Customer {$customer->email} xóa snapshot: {$snapshot->name} (ID: {$snapshot->id}) của VM #{$vm->id}",
            subject: $snapshot,
        );

        return response()->json([
            'error' => false,
            'message' => $deletedNow ? 'Đã xóa snapshot' : 'Đã gửi yêu cầu xóa snapshot vào hàng đợi',
        ]);
    }
}