#!/usr/bin/env ruby
# frozen_string_literal: true

require "gitlab"

#
# Configure credentials to be used with gitlab gem
#
Gitlab.configure do |config|
  config.endpoint = "https://gitlab.com/api/v4"
end

module Trigger
  def self.ee?
    ENV["CI_PROJECT_NAME"] == "gitlab-ee" || File.exist?("CHANGELOG-EE.md")
  end

  class Base
    def invoke!(post_comment: false)
      pipeline = Gitlab.run_trigger(
        downstream_project_path,
        trigger_token,
        ref,
        variables
      )

      puts "Triggered downstream pipeline: #{pipeline.web_url}\n"
      puts "Waiting for downstream pipeline status"

      Trigger::CommitComment.post!(pipeline, access_token) if post_comment
      Trigger::Pipeline.new(downstream_project_path, pipeline.id, access_token)
    end

    private

    # Must be overridden
    def downstream_project_path
      raise NotImplementedError
    end

    # Must be overridden
    def ref
      raise NotImplementedError
    end

    # Must be overridden
    def trigger_token
      raise NotImplementedError
    end

    # Must be overridden
    def access_token
      raise NotImplementedError
    end

    # Can be overridden
    def extra_variables
      {}
    end

    # Can be overridden
    def version_param_value(version_file)
      File.read(version_file).strip
    end

    def variables
      base_variables.merge(extra_variables).merge(version_file_variables)
    end

    def base_variables
      {
        "GITLAB_REF_SLUG" => ENV["CI_COMMIT_TAG"] ? ENV["CI_COMMIT_REF_NAME"] : ENV["CI_COMMIT_REF_SLUG"],
        "TRIGGERED_USER" => ENV["TRIGGERED_USER"] || ENV["GITLAB_USER_NAME"],
        "TRIGGER_SOURCE" => ENV["CI_JOB_URL"],
        "TOP_UPSTREAM_SOURCE_PROJECT" => ENV["CI_PROJECT_PATH"],
        "TOP_UPSTREAM_SOURCE_JOB" => ENV["CI_JOB_URL"],
        "TOP_UPSTREAM_SOURCE_SHA" => ENV["CI_COMMIT_SHA"],
      }
    end

    # Read version files from all components
    def version_file_variables
      Dir.glob("*_VERSION").each_with_object({}) do |version_file, params|
        params[version_file] = version_param_value(version_file)
      end
    end
  end

  class Omnibus < Base
    private

    def downstream_project_path
      "gitlab-org/omnibus-gitlab"
    end

    def ref
      ENV["OMNIBUS_BRANCH"] || "master"
    end

    def trigger_token
      ENV["BUILD_TRIGGER_TOKEN"]
    end

    def access_token
      ENV["GITLAB_BOT_MULTI_PROJECT_PIPELINE_POLLING_TOKEN"]
    end

    def extra_variables
      {
        "GITLAB_VERSION" => ENV["CI_COMMIT_SHA"],
        "ALTERNATIVE_SOURCES" => "true",
        "ee" => Trigger.ee? ? "true" : "false",
        "QA_BRANCH" => ENV["QA_BRANCH"] || "master",
      }
    end
  end

  class CNG < Base
    private

    def downstream_project_path
      ENV["CNG_PROJECT_PATH"] || "gitlab-org/build/CNG-mirror"
    end

    def ref
      ENV["CNG_BRANCH"] || "master"
    end

    def trigger_token
      ENV["BUILD_TRIGGER_TOKEN"]
    end

    def access_token
      ENV["GITLAB_BOT_MULTI_PROJECT_PIPELINE_POLLING_TOKEN"]
    end

    def extra_variables
      edition = Trigger.ee? ? "EE" : "CE"

      {
        # Back-compatibility until https://gitlab.com/gitlab-org/build/CNG/merge_requests/189 is merged
        "GITLAB_#{edition}_VERSION" => ENV["CI_COMMIT_REF_NAME"],
        "GITLAB_VERSION" => ENV["CI_COMMIT_REF_NAME"],
        "GITLAB_TAG" => ENV["CI_COMMIT_TAG"],
        "GITLAB_ASSETS_TAG" => ENV["CI_COMMIT_REF_SLUG"],
        "#{edition}_PIPELINE" => "true",
      }
    end

    def version_param_value(_version_file)
      raw_version = super

      # if the version matches semver format, treat it as a tag and prepend `v`
      if raw_version&.match?(Regexp.compile(/^\d+\.\d+\.\d+(-rc\d+)?(-ee)?$/))
        "v#{raw_version}"
      else
        raw_version
      end
    end
  end

  class CommitComment
    def self.post!(downstream_pipeline, access_token)
      Gitlab.private_token = access_token

      Gitlab.create_commit_comment(
        ENV["CI_PROJECT_PATH"],
        ENV["CI_COMMIT_SHA"],
        "The [`#{ENV["CI_JOB_NAME"]}`](#{ENV["CI_JOB_URL"]}) job from pipeline #{ENV["CI_PIPELINE_URL"]} triggered #{downstream_pipeline.web_url} downstream."
      )
    rescue Gitlab::Error::Error => error
      puts "Ignoring the following error: #{error}"
    end
  end

  class Pipeline
    INTERVAL = 60 # seconds
    MAX_DURATION = 3600 * 3 # 3 hours

    attr_reader :project, :id, :api_token

    def initialize(project, id, api_token)
      @project = project
      @id = id
      @api_token = api_token
      @start = Time.now.to_i

      # gitlab-bot's token "GitLab multi-project pipeline polling"
      Gitlab.private_token = api_token
    end

    def wait!
      loop do
        raise "Pipeline timed out after waiting for #{duration} minutes!" if timeout?

        case status
        when :created, :pending, :running
          print "."
          sleep INTERVAL
        when :success
          puts "Pipeline succeeded in #{duration} minutes!"
          break
        else
          raise "Pipeline did not succeed!"
        end

        STDOUT.flush
      end
    end

    def timeout?
      Time.now.to_i > (@start + MAX_DURATION)
    end

    def duration
      (Time.now.to_i - @start) / 60
    end

    def status
      Gitlab.pipeline(project, id).status.to_sym
    rescue Gitlab::Error::Error => error
      puts "Ignoring the following error: #{error}"
      # Ignore GitLab API hiccups. If GitLab is really down, we'll hit the job
      # timeout anyway.
      :running
    end
  end
end

case ARGV[0]
when "omnibus"
  Trigger::Omnibus.new.invoke!(post_comment: true).wait!
when "cng"
  Trigger::CNG.new.invoke!.wait!
else
  puts "Please provide a valid option:
  omnibus - Triggers a pipeline that builds the omnibus-gitlab package
  cng - Triggers a pipeline that builds images used by the GitLab helm chart"
end