# frozen_string_literal: true

class TeamcityService < CiService
  include ReactiveService

  prop_accessor :teamcity_url, :build_type, :username, :password

  validates :teamcity_url, presence: true, public_url: true, if: :activated?
  validates :build_type, presence: true, if: :activated?
  validates :username,
    presence: true,
    if: ->(service) { service.activated? && service.password }
  validates :password,
    presence: true,
    if: ->(service) { service.activated? && service.username }

  attr_accessor :response

  after_save :compose_service_hook, if: :activated?
  before_update :reset_password

  class << self
    def to_param
      'teamcity'
    end

    def supported_events
      %w(push merge_request)
    end

    def event_description(event)
      case event
      when 'push', 'push_events'
        'TeamCity CI will be triggered after every push to the repository except branch delete'
      when 'merge_request', 'merge_request_events'
        'TeamCity CI will be triggered after a merge request has been created or updated'
      end
    end
  end

  def compose_service_hook
    hook = service_hook || build_service_hook
    hook.save
  end

  def reset_password
    if teamcity_url_changed? && !password_touched?
      self.password = nil
    end
  end

  def title
    'JetBrains TeamCity CI'
  end

  def description
    'A continuous integration and build server'
  end

  def help
    'You will want to configure monitoring of all branches so merge '\
    'requests build, that setting is in the vsc root advanced settings.'
  end

  def fields
    [
      { type: 'text', name: 'teamcity_url',
        placeholder: 'TeamCity root URL like https://teamcity.example.com', required: true },
      { type: 'text', name: 'build_type',
        placeholder: 'Build configuration ID', required: true },
      { type: 'text', name: 'username',
        placeholder: 'A user with permissions to trigger a manual build' },
      { type: 'password', name: 'password' }
    ]
  end

  def build_page(sha, ref)
    with_reactive_cache(sha, ref) {|cached| cached[:build_page] }
  end

  def commit_status(sha, ref)
    with_reactive_cache(sha, ref) {|cached| cached[:commit_status] }
  end

  def calculate_reactive_cache(sha, ref)
    response = get_path("httpAuth/app/rest/builds/branch:unspecified:any,revision:#{sha}")

    { build_page: read_build_page(response), commit_status: read_commit_status(response) }
  end

  def execute(data)
    return unless supported_events.include?(data[:object_kind])

    case data[:object_kind]
    when 'push'
      branch = Gitlab::Git.ref_name(data[:ref])
      post_to_build_queue(data, branch) if push_valid?(data)
    when 'merge_request'
      branch = data[:object_attributes][:source_branch]
      post_to_build_queue(data, branch) if merge_request_valid?(data)
    end
  end

  private

  def read_build_page(response)
    if response.code != 200
      # If actual build link can't be determined,
      # send user to build summary page.
      build_url("viewLog.html?buildTypeId=#{build_type}")
    else
      # If actual build link is available, go to build result page.
      built_id = response['build']['id']
      build_url("viewLog.html?buildId=#{built_id}&buildTypeId=#{build_type}")
    end
  end

  def read_commit_status(response)
    return :error unless response.code == 200 || response.code == 404

    status = if response.code == 404
               'Pending'
             else
               response['build']['status']
             end

    return :error unless status.present?

    if status.include?('SUCCESS')
      'success'
    elsif status.include?('FAILURE')
      'failed'
    elsif status.include?('Pending')
      'pending'
    else
      :error
    end
  end

  def build_url(path)
    Gitlab::Utils.append_path(teamcity_url, path)
  end

  def get_path(path)
    Gitlab::HTTP.get(build_url(path), verify: false, basic_auth: basic_auth)
  end

  def post_to_build_queue(data, branch)
    Gitlab::HTTP.post(
      build_url('httpAuth/app/rest/buildQueue'),
      body: "<build branchName=#{branch.encode(xml: :attr)}>"\
            "<buildType id=#{build_type.encode(xml: :attr)}/>"\
            '</build>',
      headers: { 'Content-type' => 'application/xml' },
      basic_auth: basic_auth
    )
  end

  def basic_auth
    { username: username, password: password }
  end

  def push_valid?(data)
    data[:total_commits_count] > 0 &&
      !branch_removed?(data) &&
      no_open_merge_requests?(data)
  end

  def merge_request_valid?(data)
    data.dig(:object_attributes, :state) == 'opened' &&
      MergeRequest.state_machines[:merge_status].check_state?(data.dig(:object_attributes, :merge_status))
  end

  def branch_removed?(data)
    Gitlab::Git.blank_ref?(data[:after])
  end

  def no_open_merge_requests?(data)
    !project.merge_requests
      .opened
      .from_project(project)
      .from_source_branches(Gitlab::Git.ref_name(data[:ref]))
      .exists?
  end
end