# == Schema Information
#
# Table name: gpx_files
#
#  id          :bigint(8)        not null, primary key
#  user_id     :bigint(8)        not null
#  visible     :boolean          default(TRUE), not null
#  name        :string           default(""), not null
#  size        :bigint(8)
#  latitude    :float
#  longitude   :float
#  timestamp   :datetime         not null
#  description :string           default(""), not null
#  inserted    :boolean          not null
#  visibility  :enum             default("public"), not null
#
# Indexes
#
#  gpx_files_timestamp_idx           (timestamp)
#  gpx_files_user_id_idx             (user_id)
#  gpx_files_visible_visibility_idx  (visible,visibility)
#
# Foreign Keys
#
#  gpx_files_user_id_fkey  (user_id => users.id)
#

class Trace < ApplicationRecord
  require "open3"

  self.table_name = "gpx_files"

  belongs_to :user, :counter_cache => true
  has_many :tags, :class_name => "Tracetag", :foreign_key => "gpx_id", :dependent => :delete_all, :inverse_of => :trace
  has_many :points, :class_name => "Tracepoint", :foreign_key => "gpx_id", :dependent => :delete_all, :inverse_of => :trace

  scope :visible, -> { where(:visible => true) }
  scope :visible_to, ->(u) { visible.where("visibility IN ('public', 'identifiable') OR user_id = ?", u) }
  scope :visible_to_all, -> { where(:visibility => %w[public identifiable]) }
  scope :tagged, ->(t) { joins(:tags).where(:gpx_file_tags => { :tag => t }) }

  has_one_attached :file, :service => Settings.trace_file_storage
  has_one_attached :image, :service => Settings.trace_image_storage
  has_one_attached :icon, :service => Settings.trace_icon_storage

  validates :user, :associated => true
  validates :name, :presence => true, :length => 1..255, :characters => true
  validates :description, :presence => { :on => :create }, :length => 1..255, :characters => true
  validates :timestamp, :presence => true
  validates :visibility, :inclusion => %w[private public trackable identifiable]

  after_save :set_filename

  def tagstring
    tags.collect(&:tag).join(", ")
  end

  def tagstring=(s)
    self.tags = if s.include? ","
                  s.split(",").map(&:strip).reject(&:empty?).collect do |tag|
                    tt = Tracetag.new
                    tt.tag = tag
                    tt
                  end
                else
                  # do as before for backwards compatibility:
                  s.split.collect do |tag|
                    tt = Tracetag.new
                    tt.tag = tag
                    tt
                  end
                end
  end

  def file=(attachable)
    case attachable
    when ActionDispatch::Http::UploadedFile, Rack::Test::UploadedFile
      super(:io => attachable,
            :filename => attachable.original_filename,
            :content_type => content_type(attachable.path),
            :identify => false)
    else
      super(attachable)
    end
  end

  def public?
    visibility == "public" || visibility == "identifiable"
  end

  def trackable?
    visibility == "trackable" || visibility == "identifiable"
  end

  def identifiable?
    visibility == "identifiable"
  end

  def large_picture
    image.blob.download
  end

  def icon_picture
    icon.blob.download
  end

  def mime_type
    file.content_type
  end

  def extension_name
    case mime_type
    when "application/x-tar+gzip" then ".tar.gz"
    when "application/x-tar+x-bzip2" then ".tar.bz2"
    when "application/x-tar" then ".tar"
    when "application/zip" then ".zip"
    when "application/gzip" then ".gpx.gz"
    when "application/x-bzip2" then ".gpx.bz2"
    else ".gpx"
    end
  end

  def update_from_xml(xml, create: false)
    p = XML::Parser.string(xml, :options => XML::Parser::Options::NOERROR)
    doc = p.parse
    pt = doc.find_first("//osm/gpx_file")

    if pt
      update_from_xml_node(pt, :create => create)
    else
      raise OSM::APIBadXMLError.new("trace", xml, "XML doesn't contain an osm/gpx_file element.")
    end
  rescue LibXML::XML::Error, ArgumentError => e
    raise OSM::APIBadXMLError.new("trace", xml, e.message)
  end

  def update_from_xml_node(pt, create: false)
    raise OSM::APIBadXMLError.new("trace", pt, "visibility missing") if pt["visibility"].nil?

    self.visibility = pt["visibility"]

    unless create
      raise OSM::APIBadXMLError.new("trace", pt, "ID is required when updating.") if pt["id"].nil?

      id = pt["id"].to_i
      # .to_i will return 0 if there is no number that can be parsed.
      # We want to make sure that there is no id with zero anyway
      raise OSM::APIBadUserInput, "ID of trace cannot be zero when updating." if id.zero?
      raise OSM::APIBadUserInput, "The id in the url (#{self.id}) is not the same as provided in the xml (#{id})" unless self.id == id
    end

    # We don't care about the time, as it is explicitly set on create/update/delete
    # We don't care about the visibility as it is implicit based on the action
    # and set manually before the actual delete
    self.visible = true

    description = pt.find("description").first
    raise OSM::APIBadXMLError.new("trace", pt, "description missing") if description.nil?

    self.description = description.content

    self.tags = pt.find("tag").collect do |tag|
      Tracetag.new(:tag => tag.content)
    end
  end

  def xml_file
    file.open do |tracefile|
      filetype = Open3.capture2("/usr/bin/file", "-Lbz", tracefile.path).first.chomp
      gzipped = filetype.include?("gzip compressed")
      bzipped = filetype.include?("bzip2 compressed")
      zipped = filetype.include?("Zip archive")
      tarred = filetype.include?("tar archive")

      if gzipped || bzipped || zipped || tarred
        file = Tempfile.new("trace.#{id}")

        if tarred && gzipped
          system("tar", "-zxOf", tracefile.path, :out => file.path)
        elsif tarred && bzipped
          system("tar", "-jxOf", tracefile.path, :out => file.path)
        elsif tarred
          system("tar", "-xOf", tracefile.path, :out => file.path)
        elsif gzipped
          system("gunzip", "-c", tracefile.path, :out => file.path)
        elsif bzipped
          system("bunzip2", "-c", tracefile.path, :out => file.path)
        elsif zipped
          system("unzip", "-p", tracefile.path, "-x", "__MACOSX/*", :out => file.path, :err => "/dev/null")
        end

        file.unlink
      else
        file = File.open(tracefile.path)
      end

      file
    end
  end

  def import
    logger.info("GPX Import importing #{name} (#{id}) from #{user.email}")

    file.open do |file|
      gpx = GPX::File.new(file.path)

      f_lat = 0
      f_lon = 0
      first = true

      # If there are any existing points for this trace then delete them
      Tracepoint.where(:gpx_id => id).delete_all

      gpx.points.each_slice(1_000) do |points|
        # Gather the trace points together for a bulk import
        tracepoints = []

        points.each do |point|
          if first
            f_lat = point.latitude
            f_lon = point.longitude
            first = false
          end

          tp = Tracepoint.new
          tp.lat = point.latitude
          tp.lon = point.longitude
          tp.altitude = point.altitude
          tp.timestamp = point.timestamp
          tp.gpx_id = id
          tp.trackid = point.segment
          tracepoints << tp
        end

        # Run the before_save and before_create callbacks, and then import them in bulk with activerecord-import
        tracepoints.each do |tp|
          tp.run_callbacks(:save) { false }
          tp.run_callbacks(:create) { false }
        end

        Tracepoint.import!(tracepoints)
      end

      if gpx.actual_points.positive?
        max_lat = Tracepoint.where(:gpx_id => id).maximum(:latitude)
        min_lat = Tracepoint.where(:gpx_id => id).minimum(:latitude)
        max_lon = Tracepoint.where(:gpx_id => id).maximum(:longitude)
        min_lon = Tracepoint.where(:gpx_id => id).minimum(:longitude)

        max_lat = max_lat.to_f / 10000000
        min_lat = min_lat.to_f / 10000000
        max_lon = max_lon.to_f / 10000000
        min_lon = min_lon.to_f / 10000000

        self.latitude = f_lat
        self.longitude = f_lon
        image.attach(:io => gpx.picture(min_lat, min_lon, max_lat, max_lon, gpx.actual_points), :filename => "#{id}.gif", :content_type => "image/gif")
        icon.attach(:io => gpx.icon(min_lat, min_lon, max_lat, max_lon), :filename => "#{id}_icon.gif", :content_type => "image/gif")
        self.size = gpx.actual_points
        self.inserted = true
        save!
      end

      logger.info "done trace #{id}"

      gpx
    end
  end

  private

  def content_type(file)
    case Open3.capture2("/usr/bin/file", "-Lbz", file).first.chomp
    when /.*\btar archive\b.*\bgzip\b/ then "application/x-tar+gzip"
    when /.*\btar archive\b.*\bbzip2\b/ then "application/x-tar+x-bzip2"
    when /.*\btar archive\b/ then "application/x-tar"
    when /.*\bZip archive\b/ then "application/zip"
    when /.*\bXML\b.*\bgzip\b/ then "application/gzip"
    when /.*\bXML\b.*\bbzip2\b/ then "application/x-bzip2"
    else "application/gpx+xml"
    end
  end

  def set_filename
    file.blob.update(:filename => "#{id}#{extension_name}") if file.attached?
  end
end