# frozen_string_literal: true

# Redmine plugin for Document Management System "Features"
#
# Vít Jonáš <vit.jonas@gmail.com>, 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/>.

desc <<~END_DESC
  Convert projects' Documents to DMSF folder/file structure.

  Converted project must have Document module enabled

  Available options:
    * project - id or identifier of a project (default to all projects)
    * dry_run - perform just a check without any conversion
    * issues - Convert also files attached to issues

  Example:
    rake redmine:dmsf_convert_documents project=test RAILS_ENV="production"
    rake redmine:dmsf_convert_documents project=test dry_run=1 RAILS_ENV="production"
    rake redmine:dmsf_convert_documents project=test issues=1 RAILS_ENV="production"
END_DESC

# Convert documents
class DmsfConvertDocuments
  def initialize
    @dry_run = ENV.fetch('dry_run', nil)
    @projects = []
    if ENV['project']
      p = Project.find(ENV['project'])
      @projects << p if p&.active?
    else
      @projects.concat(Project.active.to_a)
    end
    @issues = ENV.fetch('issues', nil)
  end

  def convert_projects
    if @projects.any?
      @projects.each do |project|
        $stdout.puts "Processing project: #{project.name}"
        convert_documents(project) if project.module_enabled?('documents')
        convert_issues(project) if @issues && project.module_enabled?('issue_tracking')
      end
    else
      warn 'No active projects found.'
    end
  end

  def convert_issues(project)
    $stdout.puts 'Issues'
    unless Setting.plugin_redmine_dmsf['dmsf_act_as_attachable']
      warn "'Act as attachable' must be checked in the plugin's settings"
      return
    end
    project.issues.each do |issue|
      next unless issue.attachments.any?

      $stdout.puts "Processing: #{issue}"
      # <issue.id> - <issue.subject> folder
      if @dry_run
        $stdout.puts "Dry run #{issue.id} - #{DmsfFolder.get_valid_title(issue.subject)} folder"
      else
        project.enable_module!('dmsf')
        $stdout.puts "Creating #{issue.id} - #{DmsfFolder.get_valid_title(issue.subject)} folder"
        folder = issue.system_folder(create: true, prj_id: project.id)
      end
      files = []
      attachments = []
      issue.attachments.each do |attachment|
        @fail = false
        create_document_from_attachment(project, folder, attachment, files, issue)
        attachments << attachment unless @fail
      end
      next if @dry_run

      attachments.each do |attachment|
        issue.init_journal User.anonymous
        issue.attachments.delete attachment
      end
    end
  end

  def convert_documents(project)
    @fail = false
    folders = []
    if project.documents.any?
      $stdout.puts 'Documents'
      project.enable_module!('dmsf') unless @dry_run
      project.documents.each do |document|
        $stdout.puts "Processing document: #{document.title}"
        folder = DmsfFolder.new
        folder.project = project
        attachment = document.attachments.reorder(created_on: :asc).first
        folder.user = attachment ? attachment.author : User.active.where(admin: true).first
        folder.title = DmsfFolder.get_valid_title(document.title)
        i = 1
        suffix = ''
        while folders.index { |f| f.title == (folder.title + suffix) }
          i += 1
          suffix = "_#{i}"
        end
        folder.title = folder.title + suffix
        folder.description = document.description
        if @dry_run
          $stdout.puts "Dry run folder: #{folder.title}"
          warn(folder.errors.full_messages.to_sentence) if folder.invalid?
        else
          begin
            folder.save!
            $stdout.puts "Created folder: #{folder.title}"
          rescue StandardError => e
            warn "Creating folder: #{folder.title} failed"
            warn e.message
            @fail = true
            next
          end
        end
        folders << folder
        files = []
        @fail = false
        document.attachments.each do |a|
          create_document_from_attachment(project, folder, a, files, document)
        end
        document.destroy unless @dry_run || @fail
      end
    end
    project.disable_module!('documents') unless @dry_run || @fail
  end

  private

  def create_document_from_attachment(project, folder, attachment, files, container)
    file = DmsfFile.new
    file.project_id = project.id
    file.dmsf_folder = folder
    file.name = attachment.filename
    i = 1
    suffix = ''
    filename = DmsfFileRevision.remove_extension(file.name)
    extname = File.extname(file.name)
    while files.index { |f| f.name == "#{filename}#{suffix}#{extname}" }
      i += 1
      suffix = "_#{i}"
    end
    # Need to save file first to generate id for it in case of creation.
    # File id is needed to properly generate revision disk filename
    file.name = DmsfFileRevision.remove_extension(file.name) + suffix + File.extname(file.name)
    unless File.exist?(attachment.diskfile)
      warn "Creating file: #{attachment.filename} failed, attachment file #{attachment.diskfile} doesn't exist"
      @fail = true
      return
    end
    if @dry_run
      file.id = attachment.id # Just to have an ID there
      $stdout.puts "Dry run file: #{file.name}"
      warn(file.errors.full_messages.to_sentence) if file.invalid?
    else
      file.save!
    end
    revision = DmsfFileRevision.new
    revision.dmsf_file = file
    revision.name = file.name
    revision.title = DmsfFileRevision.filename_to_title(attachment.filename)
    revision.description = attachment.description
    revision.user = attachment.author
    revision.created_at = attachment.created_on
    revision.updated_at = attachment.created_on
    revision.major_version = 0
    revision.minor_version = 1
    revision.comment = "Converted from #{container.class.name}"
    revision.mime_type = attachment.content_type
    revision.disk_filename = revision.new_storage_filename
    if @dry_run
      $stdout.puts "Dry run revision: #{revision.title}"
      warn(revision.errors.full_messages.to_sentence) if revision.invalid?
    else
      FileUtils.cp attachment.diskfile, revision.disk_file(search_if_not_exists: false)
      revision.size = File.size(revision.disk_file(search_if_not_exists: false))
      revision.save!
    end
    files << file
    unless @dry_run
      attachment.destroy
      $stdout.puts "Created file: #{file.name}"
    end
  rescue StandardError => e
    warn "Creating file: #{attachment.filename} failed"
    warn e.message
    @fail = true
  end
end

namespace :redmine do
  task dmsf_convert_documents: :environment do
    convert = DmsfConvertDocuments.new
    convert.convert_projects
  end
end