<?php
namespace ProVM\Common\Service;

use ProVM\Common\Exception\Database\BlankResult;
use Psr\Log\LoggerInterface;
use Ddeboer\Imap\Message\AttachmentInterface;
use Ddeboer\Imap\MessageInterface;
use Safe\Exceptions\FilesystemException;
use ProVM\Common\Exception\Message\NoAttachments;
use ProVM\Emails\Model\Message;
use ProVM\Emails\Repository\Attachment;
use function Safe\{file_get_contents,file_put_contents};

class Attachments extends Base
{
    public function __construct(Messages $messages, Attachment $repository, Remote\Attachments $remoteService,
                                Decrypt $decrypt, string $attachments_folder, LoggerInterface $logger)
    {
        $this->setMessages($messages)
            ->setRepository($repository)
            ->setRemoteService($remoteService)
            ->setDecrypt($decrypt)
            ->setFolder($attachments_folder)
            ->setLogger($logger);
    }

    protected Messages $messages;
    protected Attachment $repository;
    protected Remote\Attachments $remoteService;
    protected Decrypt $decrypt;
    protected string $folder;

    public function getMessages(): Messages
    {
        return $this->messages;
    }
    public function getRepository(): Attachment
    {
        return $this->repository;
    }
    public function getRemoteService(): Remote\Attachments
    {
        return $this->remoteService;
    }
    public function getDecrypt(): Decrypt
    {
        return $this->decrypt;
    }
    public function getFolder(): string
    {
        return $this->folder;
    }

    public function setMessages(Messages $messages): Attachments
    {
        $this->messages = $messages;
        return $this;
    }
    public function setRepository(Attachment $repository): Attachments
    {
        $this->repository = $repository;
        return $this;
    }
    public function setRemoteService(Remote\Attachments $service): Attachments
    {
        $this->remoteService = $service;
        return $this;
    }
    public function setDecrypt(Decrypt $decrypt): Attachments
    {
        $this->decrypt = $decrypt;
        return $this;
    }
    public function setFolder(string $folder): Attachments
    {
        $this->folder = $folder;
        return $this;
    }

    public function getLocalAttachment(Message $message, string $relative_filename): \ProVM\Emails\Model\Attachment
    {
        return $this->getRepository()->fetchByMessageAndFilename($message->getId(), $relative_filename);
    }
    public function getRemoteAttachment(Message $message, string $relative_filename): AttachmentInterface
    {
        $remote_message = $this->getMessages()->getRemoteMessage($message->getUID());
        return $this->getRemoteService()->get($remote_message, $relative_filename);
    }
    public function getFile(int $attachment_id): string
    {
        $attachment = $this->getRepository()->fetchById($attachment_id);
        $filename = implode(DIRECTORY_SEPARATOR, [
            $this->getFolder(),
            $attachment->getFullFilename()
        ]);
        if ($attachment->isDecrypted()) {
            $filename = implode(DIRECTORY_SEPARATOR, [
                $this->getFolder(),
                'decrypted',
                $attachment->getFullFilename()
            ]);
        }
        return file_get_contents($filename);
    }

    public function getAll(): array
    {
        return $this->getRepository()->fetchAll();
    }
    public function getDownloadedFiles(): array
    {
        $downloaded = [];
        $folder = $this->getFolder();
        $files = new \FilesystemIterator($folder);
        foreach ($files as $file) {
            if ($file->isDir()) {
                continue;
            }
            $name = $file->getBasename(".{$file->getExtension()}");
            list($date, $subject, $filename) = explode(' - ', $name);
            try {
                $message = $this->getMessages()->find($subject, $date)[0];
                $filename = "{$filename}.{$file->getExtension()}";
                $downloaded []= compact('message', 'filename');
            } catch (BlankResult $e) {
            }
        }
        return $downloaded;
    }
    public function create(int $message_id): array
    {
        $message = $this->getMessages()->getRepository()->fetchById($message_id);
        $remote_message = $this->getMessages()->getRemoteMessage($message->getUID());
        if (!$remote_message->hasAttachments()) {
            throw new NoAttachments($remote_message);
        }
        $attachments = [];
        foreach ($remote_message->getAttachments() as $attachment) {
            if (!$this->getMessages()->validateAttachment($attachment)) {
                continue;
            }
            if ($this->save($message, $attachment, false)) {
                $attachments []= $attachment->getFilename();
            }
        }
        return $attachments;
    }
    public function grab(int $message_id): array
    {
        $message = $this->getMessages()->getRepository()->fetchById($message_id);
        $remote_message = $this->getMessages()->getRemoteMessage($message->getUID());
        if (!$remote_message->hasAttachments()) {
            throw new NoAttachments($remote_message);
        }
        $attachments = [];
        foreach ($remote_message->getAttachments() as $attachment) {
            if (!$this->getMessages()->validateAttachment($attachment)) {
                continue;
            }
            if ($this->save($message, $attachment)) {
                $attachments []= $attachment->getFilename();
            }
        }
        return $attachments;
    }
    public function save(Message $message, AttachmentInterface $remote_attachment, bool $upload = true): bool
    {
        $data = [
            'message_id' => $message->getId(),
            'filename' => $remote_attachment->getFilename()
        ];
        try {
            $attachment = $this->getRepository()->create($data);
            $this->getRepository()->save($attachment);
            if ($upload and $this->upload($attachment, $remote_attachment)) {
                $attachment->itIsDownloaded();
                $message->doesHaveDownloadedAttachments();
                $this->getMessages()->getRepository()->save($message);

                if ($this->isFileEncrypted($attachment->getMessage(), $attachment->getFilename())) {
                    $attachment->itIsEncrypted();

                    if ($this->isFileDecrypted($attachment->getMessage(), $attachment->getFilename())) {
                        $attachment->itIsDecrypted();
                    } else {
                        if ($this->decrypt($attachment->getMessage(), $attachment->getFilename())) {
                            $attachment->itIsDecrypted();
                        }
                    }
                }
            }
            $this->getRepository()->save($attachment);
            return true;
        } catch (PDOException $e) {
            $this->getLogger()->error($e);
            return false;
        }
    }
    public function upload(\ProVM\Emails\Model\Attachment $attachment, AttachmentInterface $remote_attachment): bool
    {
        $destination = implode(DIRECTORY_SEPARATOR, [
            $this->getFolder(),
            $attachment->getFullFilename()
        ]);
        try {
            file_put_contents($destination, $remote_attachment->getDecodedContent());
            return true;
        } catch (FilesystemException $e) {
            $this->getLogger()->error($e);
            return false;
        }
    }
    public function isFileEncrypted(Message $message, string $relative_filename): bool
    {
        $attachment = $this->getLocalAttachment($message, $relative_filename);
        $filename = implode(DIRECTORY_SEPARATOR, [
            $this->getFolder(),
            $attachment->getFullFilename()
        ]);
        try {
            return $this->getDecrypt()->isEncrypted($filename);
        } catch (\InvalidArgumentException $e) {
            return false;
        }
    }
    public function isFileDecrypted(Message $message, string $relative_filename): bool
    {
        $attachment = $this->getLocalAttachment($message, $relative_filename);
        $filename = implode(DIRECTORY_SEPARATOR, [
            $this->getFolder(),
            'decrypted',
            $attachment->getFullFilename()
        ]);
        try {
            return !$this->getDecrypt()->isEncrypted($filename);
        } catch (\InvalidArgumentException $e) {
            return false;
        }
    }
    public function decrypt(Message $message, string $relative_filename): bool
    {
        $attachment = $this->getLocalAttachment($message, $relative_filename);
        $source = implode(DIRECTORY_SEPARATOR, [
            $this->getFolder(),
            $attachment->getFullFilename()
        ]);
        $destination = implode(DIRECTORY_SEPARATOR, [
            $this->getFolder(),
            'decrypted',
            $attachment->getFullFilename()
        ]);
        return $this->getDecrypt()->runCommand($source, $destination);
    }
    public function isDownloaded(Message $message, MessageInterface $remote_message): bool
    {
        if (!$message->hasValidAttachments()) {
            return false;
        }
        if ($message->hasDownloadedAttachments()) {
            return true;
        }
        foreach ($remote_message->getAttachments() as $attachment) {
            if (!str_contains($attachment->getFilename(), '.pdf')) {
                continue;
            }
            $attachment = $this->getLocalAttachment($message, $attachment->getFilename());
            if (!$attachment->isDownloaded()) {
                return false;
            }
        }
        return true;
    }
    public function find(Message $message, string $filename): \ProVM\Emails\Model\Attachment
    {
        return $this->getRepository()->fetchByMessageAndFilename($message->getId(), $filename);
    }
    public function exists(Message $message, string $filename): bool
    {
        try {
            $this->find($message, $filename);
            return true;
        } catch (BlankResult $e) {
            return false;
        }
    }
    public function add(Message $message, string $filename): bool
    {
        $data = [
            'message_id' => $message->getId(),
            'filename' => $filename
        ];
        try {
            $attachment = $this->getRepository()->create($data);
            $attachment->itIsDownloaded();
            $this->getRepository()->save($attachment);
            $message->doesHaveDownloadedAttachments();
            $this->getMessages()->getRepository()->save($message);
            return true;
        } catch (PDOException $e) {
            $this->getLogger()->error($e);
            return false;
        }
    }
    public function checkDownloaded(): void
    {
        $data = $this->getDownloadedFiles();
        foreach ($data as $info) {
            if (!$this->exists($info['message'], $info['filename'])) {
                $this->logger->info("Updating attachment {$info['filename']} for message {$info['message']->getSubject()}");
                $this->add($info['message'], $info['filename']);
            }
        }
    }
    public function getDownloaded(): array
    {
        return $this->getRepository()->fetchDownloaded();
    }
    public function checkEncryption(): void
    {
        $attachments = $this->getDownloaded();
        foreach ($attachments as $attachment) {
            if ($attachment->isEncrypted() and !$attachment->isDecrypted()) {
                $this->logger->notice("Schedule decrypt for {$attachment->getFullFilename()}");
                $this->decrypt($attachment->getMessage(), $attachment->getFilename());
            }
        }
    }
}