class Xcodeproj::XcodebuildHelper

def self.instance
  @instance ||= new
end

def initialize
  @needs_to_parse_sdks = true
end

def last_ios_sdk
  parse_sdks_if_needed
  versions_by_sdk[:ios].sort.last
end

def last_osx_sdk
  parse_sdks_if_needed
  versions_by_sdk[:osx].sort.last
end

def last_tvos_sdk
  parse_sdks_if_needed
  versions_by_sdk[:tvos].sort.last
end

def last_watchos_sdk
  parse_sdks_if_needed
  versions_by_sdk[:watchos].sort.last
end

def parse_sdks_if_needed
  if @needs_to_parse_sdks
    @versions_by_sdk = {}
    @versions_by_sdk[:osx] = []
    @versions_by_sdk[:ios] = []
    @versions_by_sdk[:tvos] = []
    @versions_by_sdk[:watchos] = []
    if xcodebuild_available?
      sdks = parse_sdks_information(xcodebuild_sdks)
      sdks.each do |(name, version)|
        case
        when name == 'macosx' then @versions_by_sdk[:osx] << version
        when name == 'iphoneos' then @versions_by_sdk[:ios] << version
        when name == 'appletvos' then @versions_by_sdk[:tvos] << version
        when name == 'watchos' then @versions_by_sdk[:watchos] << version
        end
      end
    end
  end
end

def parse_sdks_information(output)
  output.scan(/-sdk (macosx|iphoneos|watchos|appletvos)(.+\w)/)
end

def xcodebuild_available?
  if @xcodebuild_available.nil?
    `which xcodebuild 2>/dev/null`
    @xcodebuild_available = $?.exitstatus.zero?
  end
  @xcodebuild_available
end

def xcodebuild_sdks
  `xcodebuild -showsdks 2>/dev/null`
end