# frozen_string_literal: true

# Redmine plugin for Document Management System "Features"
#
# Karel Pičman <karel.picman@kontron.com>
#
# This file is part of Redmine DMSF plugin.
#
# Redmine DMSF plugin is free software: you can redistribute it and/or modify it under the terms of the GNU General
# Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any
# later version.
#
# Redmine DMSF plugin is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
# the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
# more details.
#
# You should have received a copy of the GNU General Public License along with Redmine DMSF plugin. If not, see
# <https://www.gnu.org/licenses/>.

# Migrate documents in the file system
class MigrateDocuments < ActiveRecord::Migration[4.2]
  def up
    # Migrate all documents from dmsf/p_{project identifier} to dmsf/{year}/{month}
    DmsfFileRevision.find_each do |dmsf_file_revision|
      if dmsf_file_revision.dmsf_file
        if dmsf_file_revision.dmsf_file.project
          origin = disk_file(dmsf_file_revision)
          if origin
            if File.exist?(origin)
              target = dmsf_file_revision.disk_file(search_if_not_exists: false)
              if target
                if File.exist?(target)
                  msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: Target '#{target}' exists"
                  say msg
                  Rails.logger.error msg
                else
                  begin
                    FileUtils.mv origin, target, verbose: true
                    folder = storage_base_path(dmsf_file_revision)
                    Dir.rmdir(folder) if folder && Dir.empty?(folder)
                  rescue StandardError => e
                    msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: #{e.message}"
                    say msg
                    Rails.logger.error msg
                  end
                end
              else
                msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: target = nil"
                say msg
                Rails.logger.error msg
              end
            else
              msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: Origin '#{origin}' doesn't exist"
              say msg
              Rails.logger.error msg
            end
          else
            msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: disk_file = nil"
            say msg
            Rails.logger.error msg
          end
        else
          msg = "DmsfFile ID #{dmsf_file_revision.dmsf_file.id}: project = nil"
          say msg
          Rails.logger.error msg
        end
      else
        msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: dmsf_file = nil"
        say msg
        Rails.logger.error msg
      end
    end
  end

  def down
    # Migrate all documents from dmsf/{year}/{month} to dmsf/p_{project identifier}
    DmsfFileRevision.find_each do |dmsf_file_revision|
      if dmsf_file_revision.dmsf_file
        if dmsf_file_revision.dmsf_file.project
          origin = dmsf_file_revision.disk_file(search_if_not_exists: false)
          if origin
            if File.exist?(origin)
              target = disk_file(dmsf_file_revision)
              if target
                if File.exist?(target)
                  msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: Target '#{target}' exists"
                  say msg
                  Rails.logger.error msg
                else
                  begin
                    FileUtils.mv origin, target, verbose: true
                    folder = dmsf_file_revision.storage_base_path
                    Dir.rmdir(folder) if folder && Dir.empty?(folder)
                  rescue StandardError => e
                    msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: #{e.message}"
                    say msg
                    Rails.logger.error msg
                  end
                end
              else
                msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: target = nil"
                say msg
                Rails.logger.error msg
              end
            else
              msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: Origin '#{origin}' doesn't exist"
              say msg
              Rails.logger.error msg
            end
          else
            msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: disk_file = nil"
            say msg
            Rails.logger.error msg
          end
        else
          msg = "DmsfFile ID #{dmsf_file_revision.dmsf_file.id}: project = nil"
          say msg
          Rails.logger.error msg
        end
      else
        msg = "DmsfFileRevisions ID #{dmsf_file_revision.id}: dmsf_file = nil"
        say msg
        Rails.logger.error msg
      end
    end
  end

  def storage_base_path(dmsf_file_revision)
    return nil unless dmsf_file_revision&.dmsf_file&.project

    project_base = dmsf_file_revision.dmsf_file.project.identifier.gsub(/[^\w.\-]/, '_')
    "#{DmsfFile.storage_path}/p_#{project_base}"
  end

  def disk_file(dmsf_file_revision)
    path = storage_base_path(dmsf_file_revision)
    if path
      FileUtils.mkdir_p(path)
      return "#{path}/#{dmsf_file_revision.disk_filename}"
    end
    nil
  end
end