# frozen_string_literal: true

class AddInsertOrUpdateVulnerabilityReadsTrigger < Gitlab::Database::Migration[1.0]
  include Gitlab::Database::SchemaHelpers

  FUNCTION_NAME = 'insert_or_update_vulnerability_reads'
  TRIGGER_NAME = 'trigger_insert_or_update_vulnerability_reads_from_occurrences'

  def up
    execute(<<~SQL)
      CREATE OR REPLACE FUNCTION #{FUNCTION_NAME}()
      RETURNS TRIGGER
      LANGUAGE plpgsql
      AS $$
      DECLARE
        severity smallint;
        state smallint;
        report_type smallint;
        resolved_on_default_branch boolean;
      BEGIN
        IF (NEW.vulnerability_id IS NULL AND (TG_OP = 'INSERT' OR TG_OP = 'UPDATE')) THEN
          RETURN NULL;
        END IF;

        IF (TG_OP = 'UPDATE' AND OLD.vulnerability_id IS NOT NULL AND NEW.vulnerability_id IS NOT NULL) THEN
          RETURN NULL;
        END IF;

        SELECT
          vulnerabilities.severity, vulnerabilities.state, vulnerabilities.report_type, vulnerabilities.resolved_on_default_branch
        INTO
          severity, state, report_type, resolved_on_default_branch
        FROM
           vulnerabilities
        WHERE
          vulnerabilities.id = NEW.vulnerability_id;

        INSERT INTO vulnerability_reads (vulnerability_id, project_id, scanner_id, report_type, severity, state, resolved_on_default_branch, uuid, location_image, cluster_agent_id)
          VALUES (NEW.vulnerability_id, NEW.project_id, NEW.scanner_id, report_type, severity, state, resolved_on_default_branch, NEW.uuid::uuid, NEW.location->>'image', NEW.location->'kubernetes_resource'->>'agent_id')
          ON CONFLICT(vulnerability_id) DO NOTHING;
        RETURN NULL;
      END
      $$;
    SQL

    execute(<<~SQL)
      CREATE TRIGGER #{TRIGGER_NAME}
      AFTER INSERT OR UPDATE ON vulnerability_occurrences
      FOR EACH ROW
      EXECUTE PROCEDURE #{FUNCTION_NAME}();
    SQL
  end

  def down
    drop_trigger(:vulnerability_occurrences, TRIGGER_NAME)
    drop_function(FUNCTION_NAME)
  end
end