<?php

namespace App\Http\Controllers\Repuve;

use App\Http\Controllers\Controller;
use App\Http\Requests\Repuve\CancelConstanciaRequest;
use App\Models\CatalogCancellationReason;
use Illuminate\Validation\ValidationException;
use App\Models\Record;
use App\Models\Tag;
use App\Models\TagCancellationLog;
use App\Models\VehicleTagLog;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Log;
use Notsoweb\ApiResponse\Enums\ApiResponse;
use Barryvdh\DomPDF\Facade\Pdf;
use Illuminate\Routing\Controllers\HasMiddleware;

class CancellationController extends Controller implements HasMiddleware
{
    /**
     * Middleware
     */
    public static function middleware(): array
    {
        return [
            self::can('cancellations.cancel_constancia', ['cancelarConstancia']),
            self::can('cancellations.cancel_tag_no_asignado', ['cancelarTagNoAsignado']),
        ];
    }

    /**
     * Cancelar la constancia/tag
     */
    public function cancelarConstancia(CancelConstanciaRequest $request, $recordId)
    {
        try {
            DB::beginTransaction();

            // Buscar el expediente con sus relaciones
            $record = Record::with('vehicle.tag.status')->find($recordId);

            if (!$record) {
                return ApiResponse::NOT_FOUND->response([
                    'message' => 'El expediente no existe.',
                    'record_id' => $recordId,
                ]);
            }

            $vehicle = $record->vehicle;
            $tag = $vehicle->tag;

            // Validar que el vehículo tiene un tag asignado
            if (!$tag) {
                return ApiResponse::BAD_REQUEST->response([
                    'message' => 'El vehículo no tiene un tag/constancia asignada.'
                ]);
            }

            // Validar que el tag está en estado activo O cancelado (para permitir sustitución posterior)
            if (!$tag->isAssigned() && !$tag->isCancelled()) {
                return ApiResponse::BAD_REQUEST->response([
                    'message' => 'El tag debe estar asignado o cancelado. Status actual: ' . $tag->status->name
                ]);
            }

            // Validar que se proporcionen los datos de sustitución
            if (!$request->filled('new_folio') || !$request->filled('new_tag_number')) {
                return ApiResponse::BAD_REQUEST->response([
                    'message' => 'Para cancelar la constancia, debe proporcionar: nuevo folio y numero de constancia.',
                    'provided' => [
                        'new_folio' => $request->filled('new_folio'),
                        'new_tag_number' => $request->filled('new_tag_number'),
                    ],
                ]);
            }

            // Validar que el tag_number tenga exactamente 17 caracteres
            if (strlen($request->new_tag_number) !== 32) {
                return ApiResponse::BAD_REQUEST->response([
                    'message' => 'El tag_number debe tener exactamente 32 caracteres',
                    'provided_tag_number' => $request->new_tag_number,
                    'length' => strlen($request->new_tag_number),
                ]);
            }

            $isSubstitution = true;

            // Guardar información del tag anterior ANTES de cancelarlo
            $oldTagNumber = $tag->tag_number;
            $oldFolio = $tag->folio;

            // Crear registro en el log de vehículos
            if ($tag->isAssigned()) {
                $cancellationLog = VehicleTagLog::create([
                    'vehicle_id' => $vehicle->id,
                    'tag_id' => $tag->id,
                    'action_type' => 'cancelacion',
                    'cancellation_reason_id' => $request->cancellation_reason_id,
                    'cancellation_observations' => $request->cancellation_observations,
                    'cancellation_at' => now(),
                    'cancelled_by' => Auth::id(),
                    'performed_by' => Auth::id(),
                ]);

                // Actualizar estado del tag a 'cancelled'
                $tag->markAsCancelled();
            } else {
                // Si ya estaba cancelado, buscar el último log de cancelación
                $cancellationLog = VehicleTagLog::where('vehicle_id', $vehicle->id)
                    ->where('tag_id', $tag->id)
                    ->where('action_type', 'cancelacion')
                    ->latest()
                    ->first();
            }

            $newTag = null;
            $substitutionLog = null;

            if ($isSubstitution) {
                // Buscar el nuevo tag por folio
                $newTag = Tag::where('folio', $request->new_folio)->first();

                if (!$newTag) {
                    DB::rollBack();
                    return ApiResponse::NOT_FOUND->response([
                        'message' => 'El tag con el folio proporcionado no existe.',
                        'new_folio' => $request->new_folio,
                    ]);
                }

                if (!$newTag->isAvailable()) {
                    DB::rollBack();
                    return ApiResponse::BAD_REQUEST->response([
                        'message' => 'El nuevo tag no está disponible para asignación',
                        'new_folio' => $request->new_folio,
                        'current_status' => $newTag->status->name,
                    ]);
                }

                // Asignar tag_number al nuevo tag si no lo tiene
                if (!$newTag->tag_number) {
                    // Validar que el tag_number no esté usado por otro tag
                    $existingTag = Tag::where('tag_number', $request->new_tag_number)
                        ->where('id', '!=', $newTag->id)
                        ->first();

                    if ($existingTag) {
                        DB::rollBack();
                        return ApiResponse::BAD_REQUEST->response([
                            'message' => 'El tag_number ya está asignado a otro tag.',
                            'new_tag_number' => $request->new_tag_number,
                            'folio_existente' => $existingTag->folio,
                        ]);
                    }

                    $newTag->tag_number = $request->new_tag_number;
                    $newTag->save();
                } elseif ($newTag->tag_number !== $request->new_tag_number) {
                    DB::rollBack();
                    return ApiResponse::BAD_REQUEST->response([
                        'message' => 'El tag ya tiene un tag_number diferente asignado.',
                        'assigned_tag_number' => $newTag->tag_number,
                        'provided_tag_number' => $request->new_tag_number,
                    ]);
                }

                // Desasignar el tag viejo para evitar conflicto de unique constraint
                $tag->update(['vehicle_id' => null]);

                // Asignar el nuevo tag al vehículo (usa el folio del tag encontrado)
                $newTag->markAsAssigned($vehicle->id, $newTag->folio);

                // Crear log de sustitución
                $substitutionLog = VehicleTagLog::create([
                    'vehicle_id' => $vehicle->id,
                    'tag_id' => $newTag->id,
                    'action_type' => 'sustitucion',
                    'cancellation_reason_id' => $request->cancellation_reason_id,
                    'cancellation_observations' => 'Tag sustituido. Tag anterior: ' . $oldTagNumber . ' (Folio: ' . $oldFolio . '). Motivo: ' . ($request->cancellation_observations ?? ''),
                    'performed_by' => Auth::id(),
                ]);

                // Actualizar el folio del expediente con el folio del nuevo tag
                $record->update(['folio' => $newTag->folio]);
            }

            DB::commit();

            $message = $isSubstitution
                ? 'Tag cancelado y sustituido exitosamente'
                : 'Constancia cancelada exitosamente';

            // Agregar alerta si NO hay sustitución
            $alert = null;
            if (!$isSubstitution) {
                $alert = [
                    'type' => 'warning',
                    'message' => 'El tag ha sido cancelado y necesita sustitución',
                    'requires_action' => true,
                    'cancellation_date' => $cancellationLog->cancellation_at->format('d/m/Y H:i:s'),
                    'cancellation_reason' => $cancellationLog->cancellationReason->name,
                ];
            }

            return ApiResponse::OK->response([
                'message' => $message,
                'is_substitution' => $isSubstitution,
                'alert' => $alert,
                'cancellation' => [
                    'id' => $cancellationLog->id,
                    'vehicle' => [
                        'id' => $vehicle->id,
                        'placa' => $vehicle->placa,
                        'niv' => $vehicle->niv,
                    ],
                    'old_tag' => [
                        'id' => $tag->id,
                        'folio' => $oldFolio,
                        'tag_number' => $oldTagNumber,
                        'new_status' => 'Cancelado',
                    ],
                    'new_tag' => $newTag ? [
                        'id' => $newTag->id,
                        'folio' => $newTag->folio,
                        'tag_number' => $newTag->tag_number,
                        'status' => $newTag->status->name,
                    ] : null,
                    'cancellation_reason' => $cancellationLog->cancellationReason->name,
                    'cancellation_observations' => $request->cancellation_observations,
                    'cancelled_at' => $cancellationLog->cancellation_at->toDateTimeString(),
                    'cancelled_by' => Auth::user()->name,
                ]
            ]);
        } catch (\Exception $e) {
            DB::rollBack();

            Log::error('Error en cancelarConstancia: ' . $e->getMessage(), [
                'record_id' => $recordId ?? null,
                'cancellation_reason' => $request->cancellation_reason ?? null,
                'trace' => $e->getTraceAsString()
            ]);

            return ApiResponse::BAD_REQUEST->response([
                'message' => 'Error al cancelar la constancia',
                'error' => $e->getMessage()
            ]);
        }
    }

    public function cancelarTagNoAsignado(Request $request)
    {
        try {
            $request->validate([
                'folio' => 'required|string|exists:tags,folio',
                'cancellation_reason_id' => 'required|exists:catalog_cancellation_reasons,id',
                'cancellation_observations' => 'nullable|string',
                'module_id' => 'nullable|exists:modules,id',
            ]);

            DB::beginTransaction();

            $tag = Tag::where('folio', $request->folio)->first();

            if (!$tag) {
                DB::rollBack();
                return ApiResponse::NOT_FOUND->response([
                    'message' => 'No se encontró el tag con el folio proporcionado.',
                    'folio' => $request->folio,
                ]);
            }

            // Validar que el tag NO esté asignado
            if ($tag->isAssigned()) {
                DB::rollBack();
                return ApiResponse::BAD_REQUEST->response([
                    'message' => 'Este tag está asignado a un vehículo. Usa el endpoint de cancelación de constancia.',
                    'tag_status' => $tag->status->name,
                ]);
            }

            // Validar que no esté ya cancelado
            if ($tag->isCancelled()) {
                DB::rollBack();
                return ApiResponse::BAD_REQUEST->response([
                    'message' => 'El tag ya está cancelado.',
                ]);
            }

            $observations = $request->cancellation_observations;

            // Verificar que existe el motivo de cancelación ANTES de crear el log
            $cancellationReason = CatalogCancellationReason::find($request->cancellation_reason_id);
            if (!$cancellationReason) {
                DB::rollBack();
                return ApiResponse::BAD_REQUEST->response([
                    'message' => 'El motivo de cancelación no existe.',
                    'cancellation_reason_id' => $request->cancellation_reason_id,
                ]);
            }

            $cancellationLog = TagCancellationLog::create([
                'tag_id' => $tag->id,
                'cancellation_reason_id' => $request->cancellation_reason_id,
                'cancellation_observations' => $observations,
                'cancellation_at' => now(),
                'cancelled_by' => Auth::id(),
            ]);

            // Cargar las relaciones necesarias ANTES de usarlas
            $cancellationLog->load(['cancellationReason', 'cancelledBy']);

            // Actualizar el módulo del tag: usar el enviado o el del usuario autenticado
            $moduleId = $request->filled('module_id') ? $request->module_id : Auth::user()->module_id;
            if ($moduleId) {
                $tag->module_id = $moduleId;
                $tag->save();
            }

            // Cancelar el tag
            $tag->markAsDamaged();

            DB::commit();

            // Recargar el tag con sus relaciones actualizadas
            $tag->load(['status', 'cancellationLogs.cancellationReason', 'cancellationLogs.cancelledBy', 'module']);

            // Obtener datos de cancelación del último log
            $lastCancellation = $tag->cancellationLogs()
                ->with(['cancellationReason', 'cancelledBy'])
                ->latest()
                ->first();

            // Validar que existe el log de cancelación
            if (!$lastCancellation) {
                DB::rollBack();
                return ApiResponse::INTERNAL_ERROR->response([
                    'message' => 'Error: No se encontró el log de cancelación después de crearlo.',
                    'tag_id' => $tag->id,
                ]);
            }

            // Preparar datos para el PDF con validaciones defensivas
            $cancellationData = [
                'fecha' => $lastCancellation->cancellation_at ? $lastCancellation->cancellation_at->format('d/m/Y') : now()->format('d/m/Y'),
                'folio' => $tag->folio ?? '',
                'tag_number' => $tag->tag_number ?? 'N/A',
                'motivo' => ($lastCancellation->cancellationReason && isset($lastCancellation->cancellationReason->name))
                    ? $lastCancellation->cancellationReason->name
                    : 'No especificado',
                'operador' => ($lastCancellation->cancelledBy && isset($lastCancellation->cancelledBy->full_name))
                    ? $lastCancellation->cancelledBy->full_name
                    : 'Sistema',
                'modulo' => ($tag->module && isset($tag->module->name)) ? $tag->module->name : 'No especificado',
                'ubicacion' => ($tag->module && isset($tag->module->address)) ? $tag->module->address : 'No especificado',
            ];

            try {
                $pdf = Pdf::loadView('pdfs.tag', [
                    'cancellation' => $cancellationData,
                ])
                    ->setPaper('a4', 'portrait')
                    ->setOptions([
                        'defaultFont' => 'sans-serif',
                        'isHtml5ParserEnabled' => true,
                        'isRemoteEnabled' => true,
                    ]);

                return $pdf->stream('constancia_cancelada_' . ($tag->tag_number ?? $tag->folio) . '.pdf');
            } catch (\Exception $e) {
                // Retornar error como JSON
                return ApiResponse::INTERNAL_ERROR->response([
                    'message' => 'Tag cancelado pero error al generar PDF',
                    'error' => $e->getMessage(),
                ]);
            }

        } catch (ValidationException $e) {
            // Errores de validación
            return ApiResponse::BAD_REQUEST->response([
                'message' => 'Error de validación',
                'errors' => $e->errors(),
            ]);

        } catch (\Exception $e) {
            DB::rollBack();
            return ApiResponse::INTERNAL_ERROR->response([
                'message' => 'Error al cancelar el tag',
                'error' => $e->getMessage(),
            ]);
        }
    }
}