module Api
  class TracesController < ApiController
    layout "site", :except => :georss

    before_action :authorize_web
    before_action :set_locale
    before_action :authorize
    before_action :api_deny_access_handler

    authorize_resource

    before_action :check_database_readable, :except => [:api_read, :api_data]
    before_action :check_database_writable, :only => [:api_create, :api_update, :api_delete]
    before_action :check_api_readable, :only => [:api_read, :api_data]
    before_action :check_api_writable, :only => [:api_create, :api_update, :api_delete]
    before_action :offline_redirect, :only => [:api_create, :api_delete, :api_data]
    around_action :api_call_handle_error

    def api_read
      trace = Trace.visible.find(params[:id])

      if trace.public? || trace.user == current_user
        render :xml => trace.to_xml.to_s
      else
        head :forbidden
      end
    end

    def api_update
      trace = Trace.visible.find(params[:id])

      if trace.user == current_user
        trace.update_from_xml(request.raw_post)
        trace.save!

        head :ok
      else
        head :forbidden
      end
    end

    def api_delete
      trace = Trace.visible.find(params[:id])

      if trace.user == current_user
        trace.visible = false
        trace.save!

        head :ok
      else
        head :forbidden
      end
    end

    def api_data
      trace = Trace.visible.find(params[:id])

      if trace.public? || trace.user == current_user
        if request.format == Mime[:xml]
          send_data(trace.xml_file.read, :filename => "#{trace.id}.xml", :type => request.format.to_s, :disposition => "attachment")
        elsif request.format == Mime[:gpx]
          send_data(trace.xml_file.read, :filename => "#{trace.id}.gpx", :type => request.format.to_s, :disposition => "attachment")
        else
          send_file(trace.trace_name, :filename => "#{trace.id}#{trace.extension_name}", :type => trace.mime_type, :disposition => "attachment")
        end
      else
        head :forbidden
      end
    end

    def api_create
      tags = params[:tags] || ""
      description = params[:description] || ""
      visibility = params[:visibility]

      if visibility.nil?
        visibility = if params[:public]&.to_i&.nonzero?
                       "public"
                     else
                       "private"
                     end
      end

      if params[:file].respond_to?(:read)
        trace = do_create(params[:file], tags, description, visibility)

        if trace.id
          render :plain => trace.id.to_s
        elsif trace.valid?
          head :internal_server_error
        else
          head :bad_request
        end
      else
        head :bad_request
      end
    end

    private

    def do_create(file, tags, description, visibility)
      # Sanitise the user's filename
      name = file.original_filename.gsub(/[^a-zA-Z0-9.]/, "_")

      # Get a temporary filename...
      filename = "/tmp/#{rand}"

      # ...and save the uploaded file to that location
      File.open(filename, "wb") { |f| f.write(file.read) }

      # Create the trace object, falsely marked as already
      # inserted to stop the import daemon trying to load it
      trace = Trace.new(
        :name => name,
        :tagstring => tags,
        :description => description,
        :visibility => visibility,
        :inserted => true,
        :user => current_user,
        :timestamp => Time.now.getutc
      )

      if trace.valid?
        Trace.transaction do
          begin
            # Save the trace object
            trace.save!

            # Rename the temporary file to the final name
            FileUtils.mv(filename, trace.trace_name)
          rescue StandardError
            # Remove the file as we have failed to update the database
            FileUtils.rm_f(filename)

            # Pass the exception on
            raise
          end

          begin
            # Clear the inserted flag to make the import daemon load the trace
            trace.inserted = false
            trace.save!
          rescue StandardError
            # Remove the file as we have failed to update the database
            FileUtils.rm_f(trace.trace_name)

            # Pass the exception on
            raise
          end
        end
      end

      # Finally save the user's preferred privacy level
      if pref = current_user.preferences.where(:k => "gps.trace.visibility").first
        pref.v = visibility
        pref.save
      else
        current_user.preferences.create(:k => "gps.trace.visibility", :v => visibility)
      end

      trace
    end

    def offline_redirect
      redirect_to :action => :offline if Settings.status == "gpx_offline"
    end
  end
end