procedure

#!/usr/bin/env ruby

require 'date'
require 'erb'
require 'optparse'
require 'optparse/date'
require 'ostruct'
require 'pathname'

class Context < OpenStruct
  def rel_eng_script(name)
    "[#{name}](https://github.com/theforeman/theforeman-rel-eng/blob/master/#{name})"
  end
end

def header(filename)
  git_commit = `git rev-parse HEAD`.strip
  git_filename = Pathname.new(filename).relative_path_from(`git rev-parse --show-toplevel`.strip)
  <<~HEADER
    This procedure was generated from [#{git_filename} at #{git_commit}](https://github.com/theforeman/theforeman-rel-eng/blob/#{git_commit}/#{git_filename})

    [ ] Make this post a wiki ([help](https://meta.discourse.org/t/create-a-wiki-post/30802))

  HEADER
end

def render_file(filename, context)
  erb = ERB.new(File.read(filename), trim_mode: '-')
  erb.filename = File.expand_path(filename)
  header(filename) + erb.result(Context.new(context).instance_eval { binding })
end

def render(project, procedure, context)
  filename = procedure_filename(project, procedure)
  puts render_file(filename, context)
end

def procedure_filename(project, procedure)
  File.join(__dir__, 'procedures', project, "#{procedure}.md.erb")
end

def bump_last(version)
  parts = version.split('.')
  (parts[0..-2] + [(parts.last.to_i + 1).to_s]).join('.')
end

def previous_release(version)
  parts = version.split('.')
  (parts[0..-2] + [(parts.last.to_i - 1).to_s]).join('.')
end

def discourse_username(name)
  name.start_with?('@') ? name : "@#{name}"
end

context = {}

global = OptionParser.new do |opts|
  opts.banner = "Usage: #{opts.program_name} [branch|release]"
end
procedures = {
	'branch' => OptionParser.new do |opts|
    opts.banner = "Usage: #{opts.program_name} branch --project [foreman|katello|candlepin] --release [X.Y] --target-date [YYYY-MM-DD] --owner [OWNER] [--engineer [ENGINEER]]"

    opts.on('--project [PROJECT]', ['foreman', 'katello', 'candlepin'],
            'Project to generate branch procedure for') do |t|
      context[:project] = t
    end
    opts.on('--release [RELEASE]', /^\d+\.\d+$/,
            'Version currently in nightly in the major.minor format, like 3.7') do |release|
      context[:release] = release
      context[:develop] = bump_last(release)
    end
    opts.on('--target-date [YYYY-MM-DD]', Date,
            'Target date that the procedure should be completed on') do |date|
      context[:target_date] = date
      context[:four_weeks_before] = date - 28
      context[:three_weeks_before] = date - 21
      context[:two_weeks_before] = date - 14
      context[:one_week_before] = date - 7
    end
    opts.on('--owner [OWNER]', "The release owner's username on Discourse") do |t|
      owner = discourse_username(t)
      context[:owner] = owner
      context[:engineer] ||= owner
    end
    opts.on('--engineer [ENGINEER]', "The release engineer's username on Discourse") do |t|
      context[:engineer] = discourse_username(t)
    end
	end,
	'release' => OptionParser.new do |opts|
    opts.on('--project [PROJECT]', ['foreman', 'katello'],
            'Project to generate release procedure for') do |project|
      context[:project] = project
    end
    opts.on('--version [FULL_VERSION]',
            /^(?<version>(?<major>\d+)\.(?<minor>\d+)\.(?<patch>\d+))([-.](?<extra>rc\d+))?$/,
            'Version that the branch will have - like 1.20.0-rc1') do |full_version, version, major, minor, patch, extra|
      debian_full_version = version + (extra ? "~#{extra.downcase}" : '') + '-1'
      is_rc = !extra.nil?
      context.merge!(
        is_rc: is_rc,
        is_first_rc: extra == 'rc1',
        is_first_ga: patch == '0' && !is_rc,
        extra: extra,
        short_version: "#{major}.#{minor}", # 1.20
        debian_full_version: debian_full_version, # 1.20.0~rc1-1
        full_version: full_version, # 1.20.0-rc1
        version: version, # 1.20.0
        short_version_minus_two: "#{major}.#{minor.to_i - 2}",
        short_version_minus_five: "#{major}.#{minor.to_i - 5}"
      )
    end
    opts.on('--foreman-version [X.Y]', /^\d+\.\d+$/, 'Foreman version, for Katello') do |foreman_version|
      context[:foreman_version] = foreman_version
    end
    opts.on('--target-date [YYYY-MM-DD]', Date,
            'Target date that the procedure should be completed on') do |date|
      context[:target_date] = date
      context[:two_weeks_before] = date - 14
      context[:one_week_before] = date - 7
    end
    opts.on('--owner [OWNER]', "The release owner's username on Discourse") do |t|
      owner = discourse_username(t)
      context[:owner] = owner
      context[:engineer] ||= owner
    end
    opts.on('--engineer [ENGINEER]', "The release engineer's username on Discourse") do |t|
      context[:engineer] = discourse_username(t)
    end
	end
}

def missing_required_option?(procedure, context)
  case context[:project]
  when 'candlepin'
    context[:release].nil?
  when 'katello'
    context[:target_date].nil? || context[:owner].nil? || (procedure == 'release' && context[:foreman_version].nil?)
  when 'foreman'
    context[:target_date].nil? || context[:owner].nil?
  else
    true
  end
end

global.order!
procedure = ARGV.shift
if procedures.key?(procedure)
  command = procedures[procedure]
  command.order!

  if missing_required_option?(procedure, context)
    STDERR.puts command.help
    exit 1
  end

  render(context[:project], procedure, context)
else
  STDERR.puts global.help
  exit 1
end