<?php
namespace Domain\Tasks;

class TaskAttachmentRepository
{
  private $mdb;
  private $upload_dir;
  private $upload_url;
  private $table_ready = false;

  public function __construct( $mdb = null, $upload_dir = null, $upload_url = '/upload/task_attachments' )
  {
    if ( $mdb )
      $this -> mdb = $mdb;
    else
    {
      global $mdb;
      $this -> mdb = $mdb;
    }

    $this -> upload_dir = $upload_dir ? rtrim( $upload_dir, '/\\' ) : getcwd() . DIRECTORY_SEPARATOR . 'upload' . DIRECTORY_SEPARATOR . 'task_attachments';
    $this -> upload_url = rtrim( $upload_url, '/' );
  }

  public function listByTaskId( $task_id )
  {
    $this -> ensureStorage();
    $rows = $this -> mdb -> select( 'tasks_attachments', '*', [
      'AND' => [ 'task_id' => (int)$task_id, 'deleted' => 0 ],
      'ORDER' => [ 'id' => 'DESC' ]
    ] );

    if ( !is_array( $rows ) )
      return [];

    foreach ( $rows as &$row )
    {
      $row['title_effective'] = self::effectiveTitle( $row['title'], $row['original_name'] );
      $row['url'] = $this -> buildPublicUrl( $row['relative_path'], $row['stored_name'] );
      $row['size_human'] = $this -> formatSize( (int)$row['file_size'] );
    }

    return $rows;
  }

  public function upload( $task_id, $user_id, array $file )
  {
    $this -> ensureStorage();

    if ( !isset( $file['error'] ) or $file['error'] !== UPLOAD_ERR_OK )
      return [ 'status' => 'error', 'msg' => 'Nie udało się wgrać pliku.' ];

    if ( !isset( $file['tmp_name'] ) or !is_uploaded_file( $file['tmp_name'] ) )
      return [ 'status' => 'error', 'msg' => 'Nieprawidłowy plik.' ];

    $original_name = trim( (string)$file['name'] );
    if ( $original_name === '' )
      return [ 'status' => 'error', 'msg' => 'Brak nazwy pliku.' ];

    $safe_original_name = self::sanitizeFileName( $original_name );
    $ext = strtolower( pathinfo( $safe_original_name, PATHINFO_EXTENSION ) );
    $stored_name = uniqid( 'att_', true ) . ( $ext ? '.' . $ext : '' );

    $relative_path = date( 'Y' ) . '/' . date( 'm' );
    $target_dir = $this -> upload_dir . DIRECTORY_SEPARATOR . str_replace( '/', DIRECTORY_SEPARATOR, $relative_path );
    if ( !is_dir( $target_dir ) )
      @mkdir( $target_dir, 0777, true );

    $target_file = $target_dir . DIRECTORY_SEPARATOR . $stored_name;
    if ( !move_uploaded_file( $file['tmp_name'], $target_file ) )
      return [ 'status' => 'error', 'msg' => 'Nie udało się zapisać pliku.' ];

    $insert = $this -> mdb -> insert( 'tasks_attachments', [
      'task_id' => (int)$task_id,
      'user_id' => (int)$user_id,
      'title' => null,
      'original_name' => $safe_original_name,
      'stored_name' => $stored_name,
      'relative_path' => $relative_path,
      'file_ext' => $ext,
      'file_size' => isset( $file['size'] ) ? (int)$file['size'] : 0,
      'date_add' => date( 'Y-m-d H:i:s' ),
      'deleted' => 0
    ] );

    if ( !$insert )
      return [ 'status' => 'error', 'msg' => 'Nie udało się zapisać załącznika w bazie.' ];

    return [ 'status' => 'success' ];
  }

  public function rename( $attachment_id, $title )
  {
    $this -> ensureStorage();
    $title = trim( (string)$title );

    return $this -> mdb -> update( 'tasks_attachments', [
      'title' => $title !== '' ? $title : null
    ], [
      'AND' => [ 'id' => (int)$attachment_id, 'deleted' => 0 ]
    ] );
  }

  public function delete( $attachment_id, $deleted_by_user_id = null )
  {
    $this -> ensureStorage();

    $attachment = $this -> mdb -> get( 'tasks_attachments', '*', [
      'AND' => [ 'id' => (int)$attachment_id, 'deleted' => 0 ]
    ] );

    if ( !$attachment )
      return false;

    $file_path = $this -> upload_dir . DIRECTORY_SEPARATOR .
                 str_replace( '/', DIRECTORY_SEPARATOR, $attachment['relative_path'] ) .
                 DIRECTORY_SEPARATOR . $attachment['stored_name'];

    if ( file_exists( $file_path ) )
      @unlink( $file_path );

    return $this -> mdb -> update( 'tasks_attachments', [
      'deleted' => 1,
      'deleted_by' => $deleted_by_user_id ? (int)$deleted_by_user_id : null,
      'date_delete' => date( 'Y-m-d H:i:s' )
    ], [ 'id' => (int)$attachment_id ] );
  }

  public static function effectiveTitle( $title, $fallback )
  {
    $title = trim( (string)$title );
    return $title !== '' ? $title : (string)$fallback;
  }

  public static function sanitizeFileName( $name )
  {
    $name = preg_replace( '/[^\p{L}\p{N}\s\.\-_]+/u', '_', (string)$name );
    $name = preg_replace( '/\s+/', '_', $name );
    $name = trim( $name, '._-' );
    return $name !== '' ? $name : 'zalacznik';
  }

  private function ensureStorage()
  {
    if ( !is_dir( $this -> upload_dir ) )
      @mkdir( $this -> upload_dir, 0777, true );

    if ( !$this -> table_ready )
    {
      $this -> ensureTable();
      $this -> table_ready = true;
    }
  }

  private function ensureTable()
  {
    $this -> mdb -> query(
      'CREATE TABLE IF NOT EXISTS `tasks_attachments` (
        `id` INT NOT NULL AUTO_INCREMENT,
        `task_id` INT NOT NULL,
        `user_id` INT NOT NULL,
        `title` VARCHAR(255) NULL,
        `original_name` VARCHAR(255) NOT NULL,
        `stored_name` VARCHAR(255) NOT NULL,
        `relative_path` VARCHAR(255) NOT NULL,
        `file_ext` VARCHAR(20) NULL,
        `file_size` INT UNSIGNED NOT NULL DEFAULT 0,
        `date_add` DATETIME NOT NULL,
        `deleted` TINYINT(1) NOT NULL DEFAULT 0,
        `deleted_by` INT NULL,
        `date_delete` DATETIME NULL,
        PRIMARY KEY (`id`),
        INDEX `idx_tasks_attachments_task` (`task_id`),
        INDEX `idx_tasks_attachments_deleted` (`deleted`)
      ) ENGINE=InnoDB DEFAULT CHARSET=utf8'
    );
  }

  private function buildPublicUrl( $relative_path, $stored_name )
  {
    return $this -> upload_url . '/' . trim( $relative_path, '/' ) . '/' . rawurlencode( $stored_name );
  }

  private function formatSize( $bytes )
  {
    if ( $bytes < 1024 )
      return $bytes . ' B';

    $kb = $bytes / 1024;
    if ( $kb < 1024 )
      return number_format( $kb, 1, '.', '' ) . ' KB';

    return number_format( $kb / 1024, 1, '.', '' ) . ' MB';
  }
}