<?php

namespace App\Services;

use App\Models\Agent;
use App\Models\IntegrationRequest;
use App\Models\IntegrationTemplate;
use App\Models\ServiceTask;
use App\Models\TaskItem;
use App\Enums\IntegrationStatus;
use App\Enums\ServiceTaskStatus;
use Illuminate\Support\Facades\DB;

class IntegrationService
{
    public function createProcess(array $data): IntegrationRequest
    {
        return DB::transaction(function () use ($data) {
            $templateId = $data['template_id'] ?? null;
            
            $request = IntegrationRequest::create([
                'agent_id' => $data['agent_id'],
                'template_id' => $templateId,
                'status' => IntegrationStatus::PendingRHValidation,
                'type' => $data['type'],
                'global_deadline' => isset($data['departure_date']) ? $data['departure_date'] : now()->addDays(15),
            ]);

            // Tasks are NOT generated here anymore. They will be generated upon RH validation.

            return $request;
        });
    }

    public function createOnboarding(array $agentData, ?int $templateId = null): IntegrationRequest
    {
        return DB::transaction(function () use ($agentData, $templateId) {
            $agent = Agent::create([
                ...$agentData,
                'integration_status' => IntegrationStatus::PendingRHValidation,
                'created_by' => auth()->id() ?? 1,
            ]);

            $request = $this->createProcess([
                'agent_id' => $agent->id,
                'template_id' => $templateId,
                'type' => 'onboarding',
            ]);

            // Notify RH users about the new request
            $rhUsers = \App\Models\User::role('RH')->get();
            \Illuminate\Support\Facades\Notification::send($rhUsers, new \App\Notifications\NewIntegrationRequestNotification($request));

            return $request;
        });
    }

    public function generateTasksFromTemplate(IntegrationRequest $request, int $templateId): void
    {
        $template = IntegrationTemplate::with('serviceItems')->findOrFail($templateId);

        foreach ($template->serviceItems->groupBy('service_id') as $serviceId => $items) {
            $serviceTask = ServiceTask::create([
                'integration_request_id' => $request->id,
                'service_id' => $serviceId,
                'status' => ServiceTaskStatus::Pending,
                'sla_deadline' => now()->addDays(3), // Default SLA
            ]);

            foreach ($items as $item) {
                TaskItem::create([
                    'service_task_id' => $serviceTask->id,
                    'label' => $item->label,
                    'is_mandatory' => $item->is_mandatory,
                    'fields_definition' => $item->fields,
                    'data' => [],
                ]);
            }

            // Notify service users
            $serviceRole = $serviceTask->service->name; // Assumption: role name matches service name
            $users = \App\Models\User::role($serviceRole)->get();
            \Illuminate\Support\Facades\Notification::send($users, new \App\Notifications\TaskAssignedNotification($serviceTask));
        }
    }

    public function validateRH(IntegrationRequest $request): void
    {
        // Transition to InProgress
        $request->update(['status' => IntegrationStatus::InProgress]);
        $request->agent->update(['validated_by_rh_at' => now(), 'integration_status' => IntegrationStatus::InProgress]);
        
        // Generate tasks if template exists
        if ($request->template_id) {
            $this->generateTasksFromTemplate($request, $request->template_id);
        }
    }

    public function checkCompletion(IntegrationRequest $request): bool
    {
        $allCompleted = $request->serviceTasks()
            ->where('status', '!=', ServiceTaskStatus::Completed)
            ->count() === 0;

        if ($allCompleted) {
            $request->update([
                'status' => IntegrationStatus::Completed,
                'completed_at' => now()
            ]);
            $request->agent->update(['integration_status' => IntegrationStatus::Completed]);
            
            // Notify RH (Standard notification)
            $rhUsers = \App\Models\User::role('RH')->get();
            \Illuminate\Support\Facades\Notification::send($rhUsers, new \App\Notifications\ProcessCompletedNotification($request));

            // Generate PDF for Prescriber and DSI
            $request->load([
                'agent', 
                'template', 
                'serviceTasks.service', 
                'serviceTasks.taskItems.completedBy'
            ]);
            
            $pdfContent = null;
            try {
                $pdf = \Barryvdh\DomPDF\Facade\Pdf::loadView('pdf.integration', [
                    'integration' => $request,
                    'agent' => $request->agent,
                    'date' => now()->format('d/m/Y'),
                ]);
                $pdf->setPaper('a4', 'portrait');
                $pdfContent = $pdf->output();
            } catch (\Exception $e) {
                \Illuminate\Support\Facades\Log::error("Failed to generate PDF for integration {$request->id}: " . $e->getMessage());
            }

            if ($pdfContent) {
                $base64Pdf = base64_encode($pdfContent);
                
                // Notify Prescriber with PDF
                if ($prescriber = $request->agent->creator) {
                    $prescriber->notify(new \App\Notifications\IntegrationCompletedWithAttachment($request, $base64Pdf));
                }

                // Notify DSI with PDF
                $dsiUsers = \App\Models\User::role('DSI')->get();
                if ($dsiUsers->count() > 0) {
                     \Illuminate\Support\Facades\Notification::send($dsiUsers, new \App\Notifications\IntegrationCompletedWithAttachment($request, $base64Pdf));
                }
            }
        }

        return $allCompleted;
    }
}