# frozen_string_literal: true

module Ci
  class Stage < Ci::ApplicationRecord
    include Ci::Partitionable
    include Ci::HasStatus
    include Importable
    include Gitlab::OptimisticLocking
    include Presentable

    self.table_name = :p_ci_stages
    self.primary_key = :id
    self.sequence_name = :ci_job_stages_id_seq

    query_constraints :id, :partition_id
    partitionable scope: :pipeline, partitioned: true

    enum status: Ci::HasStatus::STATUSES_ENUM

    belongs_to :project
    belongs_to :pipeline, ->(stage) { in_partition(stage) },
      foreign_key: :pipeline_id, partition_foreign_key: :partition_id, inverse_of: :stages

    has_many :statuses,
      ->(stage) { in_partition(stage) },
      class_name: 'CommitStatus',
      foreign_key: :stage_id,
      partition_foreign_key: :partition_id,
      inverse_of: :ci_stage
    has_many :latest_statuses,
      ->(stage) { in_partition(stage).ordered.latest },
      class_name: 'CommitStatus',
      foreign_key: :stage_id,
      partition_foreign_key: :partition_id,
      inverse_of: :ci_stage
    has_many :retried_statuses,
      ->(stage) { in_partition(stage).ordered.retried },
      class_name: 'CommitStatus',
      foreign_key: :stage_id,
      partition_foreign_key: :partition_id,
      inverse_of: :ci_stage
    has_many :processables,
      ->(stage) { in_partition(stage) },
      class_name: 'Ci::Processable',
      foreign_key: :stage_id,
      partition_foreign_key: :partition_id,
      inverse_of: :ci_stage
    has_many :builds,
      ->(stage) { in_partition(stage) },
      foreign_key: :stage_id,
      partition_foreign_key: :partition_id,
      inverse_of: :ci_stage
    has_many :bridges,
      ->(stage) { in_partition(stage) },
      foreign_key: :stage_id,
      partition_foreign_key: :partition_id,
      inverse_of: :ci_stage
    has_many :generic_commit_statuses,
      ->(stage) { in_partition(stage) },
      foreign_key: :stage_id,
      partition_foreign_key: :partition_id,
      inverse_of: :ci_stage

    scope :ordered, -> { order(position: :asc) }
    scope :in_pipelines, ->(pipelines) { where(pipeline: pipelines) }
    scope :by_name, ->(names) { where(name: names) }
    scope :by_position, ->(positions) { where(position: positions) }

    with_options unless: :importing? do
      validates :project, presence: true
      validates :pipeline, presence: true
      validates :name, presence: true
      validates :position, presence: true
    end

    after_initialize do
      self.status = DEFAULT_STATUS if self.status.nil?
    end

    before_validation unless: :importing? do
      next if position.present?

      self.position = statuses.select(:stage_idx)
        .where.not(stage_idx: nil)
        .group(:stage_idx)
        .order('COUNT(id) DESC')
        .first&.stage_idx.to_i
    end

    state_machine :status, initial: :created do
      event :enqueue do
        transition any - [:pending] => :pending
      end

      event :request_resource do
        transition any - [:waiting_for_resource] => :waiting_for_resource
      end

      event :prepare do
        transition any - [:preparing] => :preparing
      end

      event :run do
        transition any - [:running] => :running
      end

      event :wait_for_callback do
        transition any - [:waiting_for_callback] => :waiting_for_callback
      end

      event :skip do
        transition any - [:skipped] => :skipped
      end

      event :drop do
        transition any - [:failed] => :failed
      end

      event :succeed do
        transition any - [:success] => :success
      end

      event :start_cancel do
        transition any - [:canceling, :canceled] => :canceling
      end

      event :cancel do
        transition any - [:canceled] => :canceled
      end

      event :block do
        transition any - [:manual] => :manual
      end

      event :delay do
        transition any - [:scheduled] => :scheduled
      end
    end

    # rubocop: disable Metrics/CyclomaticComplexity -- breaking apart hurts readability, consider refactoring issue #439268
    def set_status(new_status)
      retry_optimistic_lock(self, name: 'ci_stage_set_status') do
        case new_status
        when 'created' then nil
        when 'waiting_for_resource' then request_resource
        when 'preparing' then prepare
        when 'waiting_for_callback' then wait_for_callback
        when 'pending' then enqueue
        when 'running' then run
        when 'success' then succeed
        when 'failed' then drop
        when 'canceling' then start_cancel
        when 'canceled' then cancel
        when 'manual' then block
        when 'scheduled' then delay
        when 'skipped', nil then skip
        else
          raise Ci::HasStatus::UnknownStatusError, "Unknown status `#{new_status}`"
        end
      end
    end
    # rubocop: enable Metrics/CyclomaticComplexity

    # This will be removed with ci_remove_ensure_stage_service
    def update_legacy_status
      set_status(latest_stage_status.to_s)
    end

    def groups
      @groups ||= Ci::Group.fabricate(project, self)
    end

    def has_warnings?
      number_of_warnings > 0
    end

    def number_of_warnings
      BatchLoader.for(id).batch(default_value: 0) do |stage_ids, loader|
        ::CommitStatus.where(stage_id: stage_ids)
          .latest
          .failed_but_allowed
          .group(:stage_id)
          .count
          .each { |id, amount| loader.call(id, amount) }
      end
    end

    def detailed_status(current_user)
      Gitlab::Ci::Status::Stage::Factory
        .new(self, current_user)
        .fabricate!
    end

    def manual_playable?
      blocked? || skipped?
    end

    # We only check jobs that are played by `Ci::PlayManualStageService`.
    def confirm_manual_job?
      processables.manual.any? do |job|
        job.playable? && job.manual_confirmation_message
      end
    end

    # This will be removed with ci_remove_ensure_stage_service
    def latest_stage_status
      statuses.latest.composite_status || 'skipped'
    end

    def ordered_latest_statuses
      preload_metadata(statuses.in_order_of(:status, Ci::HasStatus::ORDERED_STATUSES).latest_ordered)
    end

    def ordered_retried_statuses
      preload_metadata(statuses.in_order_of(:status, Ci::HasStatus::ORDERED_STATUSES).retried_ordered)
    end

    private

    def preload_metadata(statuses)
      relations = [:metadata, :pipeline, { downstream_pipeline: [:user, { project: [:route, { namespace: :route }] }] }]

      Preloaders::CommitStatusPreloader.new(statuses).execute(relations)

      statuses
    end
  end
end