# frozen_string_literal: true
require_relative "../spec_helper"

require_relative "../../lib/ultravisor"

describe Ultravisor do
  let(:args) { {} }
  let(:ultravisor) { Ultravisor.new(**args) }
  let(:mock_thread) { instance_double(Thread) }

  describe "#shutdown" do
    it "takes the @op_m lock" do
      expect(ultravisor.instance_variable_get(:@op_m)).to receive(:synchronize).and_call_original

      ultravisor.shutdown
    end

    context "when the ultravisor isn't running" do
      it "returns itself" do
        expect(ultravisor.shutdown).to eq(ultravisor)
      end
    end

    context "when the ultravisor is running" do
      before(:each) do
        ultravisor.instance_variable_set(:@running_thread, mock_thread)
        allow(ultravisor.instance_variable_get(:@op_cv))
          .to receive(:wait) do
          ultravisor.instance_variable_set(:@running_thread, nil)
        end
      end

      it "signals the ultravisor to shutdown" do
        expect(ultravisor.instance_variable_get(:@queue)).to receive(:<<).with(:shutdown)

        ultravisor.shutdown
      end

      it "waits until the CV is signalled" do
        expect(ultravisor.instance_variable_get(:@op_cv)).to receive(:wait) do |m|
          expect(m).to eq(ultravisor.instance_variable_get(:@op_m))
            ultravisor.instance_variable_set(:@running_thread, nil)
            nil
        end

        ultravisor.shutdown
      end

      context "when asked to not wait" do
        it "doesn't wait on the CV" do
          expect(ultravisor.instance_variable_get(:@op_cv)).to_not receive(:wait)

          ultravisor.shutdown(wait: false)
        end
      end

      it "returns itself" do
        expect(ultravisor.shutdown).to eq(ultravisor)
      end

      context "when forced" do
        before(:each) do
          allow(mock_thread).to receive(:kill)
        end

        it "kills the thread" do
          expect(mock_thread).to receive(:kill)

          ultravisor.shutdown(force: true)
        end

        it "tells everyone waiting for the shutdown that the deed is done" do
          expect(ultravisor.instance_variable_get(:@op_cv)).to receive(:broadcast)

          ultravisor.shutdown(force: true)
        end

        it "unsets the running thread" do
          ultravisor.shutdown(force: true)

          expect(ultravisor.instance_variable_get(:@running_thread)).to be(nil)
        end

        it "doesn't wait on the CV" do
          expect(ultravisor.instance_variable_get(:@op_cv)).to_not receive(:wait)

          ultravisor.shutdown(force: true)
        end

        context "with children" do
          let(:child) { Ultravisor::Child.new(id: :one, klass: Object, method: :to_s) }

          before(:each) do
            ultravisor.instance_variable_set(:@children, [[:child, child]])
          end

          it "forcibly shuts down the children" do
            expect(child).to receive(:shutdown).with(force: true)

            ultravisor.shutdown(force: true)
          end
        end
      end
    end
  end
end