# frozen_string_literal: true

require 'spec_helper'

RSpec.describe Ml::Candidate, factory_default: :keep, feature_category: :mlops do
  let_it_be(:candidate) { create(:ml_candidates, :with_metrics_and_params, name: 'candidate0') }
  let_it_be(:candidate2) do
    create(:ml_candidates, experiment: candidate.experiment, user: create(:user), name: 'candidate2')
  end

  let_it_be(:candidate_artifact) do
    FactoryBot.create(:generic_package,
                      name: candidate.package_name,
                      version: candidate.package_version,
                      project: candidate.project)
  end

  let(:project) { candidate.experiment.project }

  describe 'associations' do
    it { is_expected.to belong_to(:experiment) }
    it { is_expected.to belong_to(:user) }
    it { is_expected.to have_many(:params) }
    it { is_expected.to have_many(:metrics) }
    it { is_expected.to have_many(:metadata) }
  end

  describe 'default values' do
    it { expect(described_class.new.iid).to be_present }
  end

  describe '.artifact_root' do
    subject { candidate.artifact_root }

    it { is_expected.to eq("/ml_candidate_#{candidate.id}/-/") }
  end

  describe '.package_name' do
    subject { candidate.package_name }

    it { is_expected.to eq("ml_candidate_#{candidate.id}") }
  end

  describe '.package_version' do
    subject { candidate.package_version }

    it { is_expected.to eq('-') }
  end

  describe '.artifact' do
    let(:tested_candidate) { candidate }

    subject { tested_candidate.artifact }

    before do
      candidate_artifact
    end

    context 'when has logged artifacts' do
      it 'returns the package' do
        expect(subject.name).to eq(tested_candidate.package_name)
      end
    end

    context 'when does not have logged artifacts' do
      let(:tested_candidate) { candidate2 }

      it { is_expected.to be_nil }
    end
  end

  describe '.artifact_lazy' do
    context 'when candidates have same the same iid' do
      before do
        BatchLoader::Executor.clear_current
      end

      it 'loads the correct artifacts', :aggregate_failures do
        candidate.artifact_lazy
        candidate2.artifact_lazy

        expect(Packages::Package).to receive(:joins).once.and_call_original # Only one database call

        expect(candidate.artifact.name).to eq(candidate.package_name)
        expect(candidate2.artifact).to be_nil
      end
    end
  end

  describe '#by_project_id_and_iid' do
    let(:project_id) { candidate.experiment.project_id }
    let(:iid) { candidate.iid }

    subject { described_class.with_project_id_and_iid(project_id, iid) }

    context 'when iid exists', 'and belongs to project' do
      it { is_expected.to eq(candidate) }
    end

    context 'when iid exists', 'and does not belong to project' do
      let(:project_id) { non_existing_record_id }

      it { is_expected.to be_nil }
    end

    context 'when iid does not exist' do
      let(:iid) { 'a' }

      it { is_expected.to be_nil }
    end
  end

  describe "#latest_metrics" do
    let_it_be(:candidate3) { create(:ml_candidates, experiment: candidate.experiment) }
    let_it_be(:metric1) { create(:ml_candidate_metrics, candidate: candidate3) }
    let_it_be(:metric2) { create(:ml_candidate_metrics, candidate: candidate3 ) }
    let_it_be(:metric3) { create(:ml_candidate_metrics, name: metric1.name, candidate: candidate3) }

    subject { candidate3.latest_metrics }

    it 'fetches only the last metric for the name' do
      expect(subject).to match_array([metric2, metric3] )
    end
  end

  describe "#including_relationships" do
    subject { described_class.including_relationships.find_by(id: candidate.id) }

    it 'loads latest metrics and params', :aggregate_failures do
      expect(subject.association_cached?(:latest_metrics)).to be(true)
      expect(subject.association_cached?(:params)).to be(true)
      expect(subject.association_cached?(:user)).to be(true)
    end
  end

  describe '#by_name' do
    let(:name) { candidate.name }

    subject { described_class.by_name(name) }

    context 'when name matches' do
      it 'gets the correct candidates' do
        expect(subject).to match_array([candidate])
      end
    end

    context 'when name matches partially' do
      let(:name) { 'andidate' }

      it 'gets the correct candidates' do
        expect(subject).to match_array([candidate, candidate2])
      end
    end

    context 'when name does not match' do
      let(:name) { non_existing_record_id.to_s }

      it 'does not fetch any candidate' do
        expect(subject).to match_array([])
      end
    end
  end

  describe '#order_by_metric' do
    let_it_be(:auc_metrics) do
      create(:ml_candidate_metrics, name: 'auc', value: 0.4, candidate: candidate)
      create(:ml_candidate_metrics, name: 'auc', value: 0.8, candidate: candidate2)
    end

    let(:direction) { 'desc' }

    subject { described_class.order_by_metric('auc', direction) }

    it 'orders correctly' do
      expect(subject).to eq([candidate2, candidate])
    end

    context 'when direction is asc' do
      let(:direction) { 'asc' }

      it 'orders correctly' do
        expect(subject).to eq([candidate, candidate2])
      end
    end
  end
end