<?php

namespace App\Services\Posta;

use App\Models\CommunicationMessage;
use App\Models\Persona;
use App\Models\PersonaUnitaRelazione;
use App\Models\Stabile;
use App\Models\Ticket;
use App\Models\UnitaImmobiliare;
use App\Services\TenantArchivePathService;
use Carbon\Carbon;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\File;
use Illuminate\Support\Facades\Log;
use Illuminate\Support\Str;

class ImapMailboxService
{
    public function __construct(
        private readonly ImapClient $imapClient,
        private readonly EmlParser $emlParser,
        private readonly TenantArchivePathService $pathService
    ) {}

    public function testMailbox(array $config): array
    {
        $host = trim((string) ($config['host'] ?? ''));
        $port = (int) ($config['port'] ?? 993);
        $username = trim((string) ($config['username'] ?? ($config['email'] ?? '')));
        $password = (string) ($config['password'] ?? '');
        $encryption = trim((string) ($config['encryption'] ?? 'ssl')) ?: 'ssl';

        if ($host === '' || $username === '') {
            return ['success' => false, 'message' => 'Host e Username sono obbligatori per testare la connessione IMAP.'];
        }

        return $this->imapClient->testConnection($host, $port, $username, $password, $encryption);
    }

    /**
     * Scarica e memorizza le email/PEC via IMAP in formato .EML e popola CommunicationMessage e Ticket.
     *
     * @param Stabile $stabile
     * @param array $mailbox
     * @param int $maxMessages
     * @return array{imported: int, skipped: int, errors: int, messages: array}
     */
    public function fetchMailbox(Stabile $stabile, array $mailbox, int $maxMessages = 50): array
    {
        $host = trim((string) ($mailbox['host'] ?? ''));
        $port = (int) ($mailbox['port'] ?? 993);
        $username = trim((string) ($mailbox['username'] ?? ($mailbox['email'] ?? '')));
        $password = (string) ($mailbox['password'] ?? '');
        $encryption = trim((string) ($mailbox['encryption'] ?? 'ssl')) ?: 'ssl';
        $folder = trim((string) ($mailbox['folder'] ?? 'INBOX')) ?: 'INBOX';
        $isPec = strtolower(trim((string) ($mailbox['tipo'] ?? ''))) === 'pec';
        $createTicket = (bool) ($mailbox['crea_ticket_automatico'] ?? true);

        if ($host === '' || $username === '') {
            return [
                'imported' => 0,
                'skipped'  => 0,
                'errors'   => 1,
                'message'  => 'Parametri IMAP incompleti (Host / Username mancanti)',
                'messages' => [],
            ];
        }

        $stats = ['imported' => 0, 'skipped' => 0, 'errors' => 0, 'messages' => []];

        try {
            $this->imapClient->connect($host, $port, $username, $password, $encryption);
            $this->imapClient->selectFolder($folder);
            $msgIds = $this->imapClient->search('ALL');

            // Prendi i messaggi più recenti fino a $maxMessages
            $recentIds = array_slice(array_reverse($msgIds), 0, $maxMessages);

            foreach ($recentIds as $msgId) {
                try {
                    $rawEml = $this->imapClient->fetchRawEml($msgId);
                    if (trim($rawEml) === '') {
                        continue;
                    }

                    $res = $this->ingestEmlString($rawEml, $stabile, $mailbox, $isPec, $createTicket);
                    if ($res['status'] === 'imported') {
                        $stats['imported']++;
                        $stats['messages'][] = $res;
                    } elseif ($res['status'] === 'duplicate') {
                        $stats['skipped']++;
                    } else {
                        $stats['errors']++;
                    }
                } catch (\Throwable $e) {
                    $stats['errors']++;
                }
            }

            $this->imapClient->disconnect();
        } catch (\Throwable $e) {
            $stats['errors']++;
            $stats['error_message'] = $e->getMessage();
        }

        return $stats;
    }

    /**
     * Scarica e memorizza le email/PEC dello studio amministratore in formato .EML
     *
     * @param \App\Models\Amministratore $amministratore
     * @param array $mailbox
     * @param int $maxMessages
     * @return array{imported: int, skipped: int, errors: int, messages: array}
     */
    public function fetchStudioMailbox(\App\Models\Amministratore $amministratore, array $mailbox, int $maxMessages = 50): array
    {
        $host = trim((string) ($mailbox['host'] ?? ''));
        $port = (int) ($mailbox['port'] ?? 993);
        $username = trim((string) ($mailbox['username'] ?? ($mailbox['email'] ?? '')));
        $password = (string) ($mailbox['password'] ?? '');
        $encryption = trim((string) ($mailbox['encryption'] ?? 'ssl')) ?: 'ssl';
        $folder = trim((string) ($mailbox['folder'] ?? 'INBOX')) ?: 'INBOX';
        $isPec = strtolower(trim((string) ($mailbox['tipo'] ?? ''))) === 'pec';

        if ($host === '' || $username === '') {
            return [
                'imported' => 0,
                'skipped'  => 0,
                'errors'   => 1,
                'message'  => 'Parametri IMAP studio incompleti',
                'messages' => [],
            ];
        }

        $stats = ['imported' => 0, 'skipped' => 0, 'errors' => 0, 'messages' => []];

        try {
            $this->imapClient->connect($host, $port, $username, $password, $encryption);
            $this->imapClient->selectFolder($folder);
            $msgIds = $this->imapClient->search('ALL');

            $recentIds = array_slice(array_reverse($msgIds), 0, $maxMessages);

            foreach ($recentIds as $msgId) {
                try {
                    $rawEml = $this->imapClient->fetchRawEml($msgId);
                    if (trim($rawEml) === '') {
                        continue;
                    }

                    $res = $this->ingestStudioEmlString($rawEml, $amministratore, $mailbox, $isPec);
                    if ($res['status'] === 'imported') {
                        $stats['imported']++;
                        $stats['messages'][] = $res;
                    } elseif ($res['status'] === 'duplicate') {
                        $stats['skipped']++;
                    } else {
                        $stats['errors']++;
                    }
                } catch (\Throwable $e) {
                    $stats['errors']++;
                }
            }

            $this->imapClient->disconnect();
        } catch (\Throwable $e) {
            $stats['errors']++;
            $stats['error_message'] = $e->getMessage();
        }

        return $stats;
    }

    /**
     * Ingesta un messaggio EML dello studio amministratore
     */
    public function ingestStudioEmlString(
        string $rawEml,
        \App\Models\Amministratore $amministratore,
        array $mailboxConfig = [],
        bool $forcePec = false
    ): array {
        $parsed = $this->emlParser->parse($rawEml);
        $messageId = $parsed['message_id'] ?: ('studio_' . md5($rawEml));

        $existing = CommunicationMessage::whereNull('stabile_id')
            ->where(function ($q) use ($messageId) {
                $q->where('external_message_id', $messageId)
                  ->orWhere('metadata->message_id', $messageId);
            })
            ->first();

        if ($existing) {
            return ['status' => 'duplicate', 'id' => $existing->id];
        }

        $channel = ($forcePec || $parsed['is_pec']) ? 'pec' : 'email';
        $year = $parsed['date'] ? $parsed['date']->format('Y') : date('Y');

        $postaSubdir = $channel === 'pec' ? 'posta_pec' : 'posta_ordinaria';
        $storageDir = $this->pathService->amministratoreAbsolutePath($amministratore, "studio/{$postaSubdir}/{$year}");
        if (! is_dir($storageDir)) {
            @mkdir($storageDir, 0755, true);
        }

        $safeMsgId = preg_replace('/[^a-zA-Z0-9_-]/', '_', $messageId);
        $emlFilename = "{$safeMsgId}.eml";
        $emlFullPath = "{$storageDir}/{$emlFilename}";
        @file_put_contents($emlFullPath, $rawEml);

        $savedAttachments = [];
        if (! empty($parsed['attachments'])) {
            $attachmentsDir = "{$storageDir}/allegati/{$safeMsgId}";
            if (! is_dir($attachmentsDir)) {
                @mkdir($attachmentsDir, 0755, true);
            }

            foreach ($parsed['attachments'] as $idx => $att) {
                $safeName = preg_replace('/[^a-zA-Z0-9._-]/', '_', (string) $att['filename']);
                if ($safeName === '') {
                    $safeName = "allegato_{$idx}.dat";
                }
                $attPath = "{$attachmentsDir}/{$safeName}";
                @file_put_contents($attPath, $att['content']);

                $savedAttachments[] = [
                    'filename'     => $att['filename'],
                    'path'         => $attPath,
                    'content_type' => $att['content_type'],
                    'size'         => $att['size'],
                    'is_inline'    => $att['is_inline'],
                ];
            }
        }

        $senderDisplay = $parsed['from']['name'] ? "{$parsed['from']['name']} <{$parsed['from']['email']}>" : $parsed['from']['email'];

        $comm = CommunicationMessage::create([
            'channel'             => $channel,
            'direction'           => 'inbound',
            'external_message_id' => $messageId,
            'stabile_id'          => null,
            'sender_name'         => $senderDisplay,
            'phone_number'        => null,
            'message_text'        => $parsed['body_text'] ?: strip_tags((string) $parsed['body_html']),
            'attachments'         => $savedAttachments,
            'ticket_id'           => null,
            'status'              => 'received',
            'received_at'         => $parsed['date'] ?: now(),
            'metadata'            => [
                'subject'              => $parsed['subject'],
                'sender_email'         => $parsed['from']['email'],
                'sender_name'          => $parsed['from']['name'],
                'to'                   => $parsed['to'],
                'cc'                   => $parsed['cc'],
                'body_html'            => $parsed['body_html'],
                'eml_path'             => $emlFullPath,
                'is_pec'               => $channel === 'pec',
                'is_studio'            => true,
                'mailbox_label'        => $mailboxConfig['label'] ?? 'Studio',
                'mailbox_email'        => $mailboxConfig['email'] ?? '',
            ],
        ]);

        return [
            'status'          => 'imported',
            'id'              => $comm->id,
            'channel'         => $channel,
            'subject'         => $parsed['subject'],
            'from'            => $senderDisplay,
            'date'            => $parsed['date']?->format('d/m/Y H:i'),
            'has_attachments' => count($savedAttachments) > 0,
        ];
    }

    /**
     * Ingesta un messaggio da stringa EML grezza
     */
    public function ingestEmlString(
        string $rawEml,
        Stabile $stabile,
        array $mailboxConfig = [],
        bool $forcePec = false,
        bool $createTicket = true
    ): array {
        $parsed = $this->emlParser->parse($rawEml);
        $messageId = $parsed['message_id'] ?: ('local_' . md5($rawEml));

        // Verifica duplicati su CommunicationMessage
        $existing = CommunicationMessage::where('stabile_id', $stabile->id)
            ->where(function ($q) use ($messageId) {
                $q->where('external_message_id', $messageId)
                  ->orWhere('metadata->message_id', $messageId);
            })
            ->first();

        if ($existing) {
            return ['status' => 'duplicate', 'id' => $existing->id];
        }

        $channel = ($forcePec || $parsed['is_pec']) ? 'pec' : 'email';
        $year = $parsed['date'] ? $parsed['date']->format('Y') : date('Y');

        // Cartelle dedicate di archiviazione .EML
        $postaSubdir = $channel === 'pec' ? 'posta_pec' : 'posta_ordinaria';
        $storageDir = $this->pathService->stabileAbsolutePath($stabile, "{$postaSubdir}/{$year}");
        if (! is_dir($storageDir)) {
            @mkdir($storageDir, 0755, true);
        }

        $safeMsgId = preg_replace('/[^a-zA-Z0-9_-]/', '_', $messageId);
        $emlFilename = "{$safeMsgId}.eml";
        $emlFullPath = "{$storageDir}/{$emlFilename}";
        @file_put_contents($emlFullPath, $rawEml);

        // Salva gli allegati estratti
        $savedAttachments = [];
        if (! empty($parsed['attachments'])) {
            $attachmentsDir = "{$storageDir}/allegati/{$safeMsgId}";
            if (! is_dir($attachmentsDir)) {
                @mkdir($attachmentsDir, 0755, true);
            }

            foreach ($parsed['attachments'] as $idx => $att) {
                $safeName = preg_replace('/[^a-zA-Z0-9._-]/', '_', (string) $att['filename']);
                if ($safeName === '') {
                    $safeName = "allegato_{$idx}.dat";
                }
                $attPath = "{$attachmentsDir}/{$safeName}";
                @file_put_contents($attPath, $att['content']);

                $savedAttachments[] = [
                    'filename'     => $att['filename'],
                    'path'         => $attPath,
                    'content_type' => $att['content_type'],
                    'size'         => $att['size'],
                    'is_inline'    => $att['is_inline'],
                ];
            }
        }

        // Risoluzione Unità Immobiliare associata al mittente
        $matchedUnita = $this->matchUnitaBySender($stabile, $parsed['from']['email']);

        // Creazione Ticket opzionale
        $ticketId = null;
        if ($createTicket) {
            try {
                $userId = \Illuminate\Support\Facades\Auth::id();
                if (! $userId && $stabile->amministratore_id) {
                    $userId = DB::table('amministratori')->where('id', $stabile->amministratore_id)->value('user_id');
                }
                if (! $userId) {
                    $userId = \App\Models\User::query()->value('id') ?: 1;
                }

                $ticket = Ticket::create([
                    'stabile_id'           => $stabile->id,
                    'unita_immobiliare_id' => $matchedUnita?->id,
                    'aperto_da_user_id'    => (int) $userId,
                    'titolo'               => Str::limit($parsed['subject'], 180, '...'),
                    'descrizione'          => Str::limit($parsed['body_text'] ?: strip_tags((string) $parsed['body_html']), 1000),
                    'priorita'             => $channel === 'pec' ? 'Alta' : 'Media',
                    'stato'                => 'Aperto',
                    'data_apertura'        => now(),
                ]);
                $ticketId = $ticket->id;
            } catch (\Throwable $e) {
                Log::warning('ImapMailboxService: Ticket creation failed: ' . $e->getMessage());
            }
        }

        // Creazione CommunicationMessage
        $senderDisplay = $parsed['from']['name'] ? "{$parsed['from']['name']} <{$parsed['from']['email']}>" : $parsed['from']['email'];

        $comm = CommunicationMessage::create([
            'channel'             => $channel,
            'direction'           => 'inbound',
            'external_message_id' => $messageId,
            'stabile_id'          => $stabile->id,
            'sender_name'         => $senderDisplay,
            'phone_number'        => null,
            'message_text'        => $parsed['body_text'] ?: strip_tags((string) $parsed['body_html']),
            'attachments'         => $savedAttachments,
            'ticket_id'           => $ticketId,
            'status'              => 'received',
            'received_at'         => $parsed['date'] ?: now(),
            'metadata'            => [
                'subject'              => $parsed['subject'],
                'sender_email'         => $parsed['from']['email'],
                'sender_name'          => $parsed['from']['name'],
                'to'                   => $parsed['to'],
                'cc'                   => $parsed['cc'],
                'body_html'            => $parsed['body_html'],
                'eml_path'             => $emlFullPath,
                'is_pec'               => $channel === 'pec',
                'unita_immobiliare_id' => $matchedUnita?->id,
                'codice_unita'         => $matchedUnita?->codice_unita,
                'mailbox_label'        => $mailboxConfig['label'] ?? '',
                'mailbox_email'        => $mailboxConfig['email'] ?? '',
            ],
        ]);

        return [
            'status'     => 'imported',
            'id'         => $comm->id,
            'channel'    => $channel,
            'subject'    => $parsed['subject'],
            'from'       => $senderDisplay,
            'date'       => $parsed['date']?->format('d/m/Y H:i'),
            'ticket_id'  => $ticketId,
            'unita_id'   => $matchedUnita?->id,
            'has_attachments' => count($savedAttachments) > 0,
        ];
    }

    private function matchUnitaBySender(Stabile $stabile, string $senderEmail): ?UnitaImmobiliare
    {
        $senderEmail = strtolower(trim($senderEmail));
        if ($senderEmail === '') {
            return null;
        }

        // Cerca persone associate all'email o contatti
        $personaIds = Persona::where('email_principale', $senderEmail)
            ->orWhere('email_secondaria', $senderEmail)
            ->orWhere('pec', $senderEmail)
            ->pluck('id')
            ->toArray();

        if (empty($personaIds)) {
            // Cerca in rubrica o recapiti
            if (DB::getSchemaBuilder()->hasTable('rubrica_universale')) {
                $rubricaIds = DB::table('rubrica_universale')
                    ->where(function ($q) use ($senderEmail) {
                        $q->where('email', $senderEmail)
                          ->orWhere('email_secondaria', $senderEmail)
                          ->orWhere('pec', $senderEmail);
                    })
                    ->pluck('id')
                    ->toArray();

                if (! empty($rubricaIds) && DB::getSchemaBuilder()->hasTable('rubrica_ruoli')) {
                    $unitaId = DB::table('rubrica_ruoli')
                        ->where('stabile_id', $stabile->id)
                        ->whereIn('rubrica_id', $rubricaIds)
                        ->whereNotNull('unita_immobiliare_id')
                        ->value('unita_immobiliare_id');

                    if ($unitaId) {
                        return UnitaImmobiliare::find($unitaId);
                    }
                }
            }
            return null;
        }

        $unitaId = PersonaUnitaRelazione::whereIn('persona_id', $personaIds)
            ->whereHas('unita', fn($q) => $q->where('stabile_id', $stabile->id))
            ->value('unita_id');

        return $unitaId ? UnitaImmobiliare::find($unitaId) : null;
    }
}