module KPM::SystemProxy::MemoryInformation

def fetch
  memory_info = nil
  if OS.windows?
    memory_info = fetch_windows
  elsif OS.linux?
    memory_info = fetch_linux
  elsif OS.mac?
    memory_info = fetch_mac
  end
  memory_info
end

def fetch_linux
  mem_data = `cat /proc/meminfo 2>&1`.gsub("\t",'')
  mem = get_hash(mem_data)
  mem
end

def fetch_mac
  mem_data = `vm_stat 2>&1`.gsub(".",'')
  mem = get_hash(mem_data)
  mem.each_key do |key|
    mem[key][:value] = ((mem[key][:value].to_i * 4096) / 1024 / 1024).to_s + 'MB'
    mem[key][:memory_detail] = mem[key][:memory_detail].gsub('Pages','Memory')
  end
  mem_total_data = `system_profiler SPHardwareDataType | grep "  Memory:" 2>&1`
  mem_total = get_hash(mem_total_data)
  mem = mem_total.merge(mem)
  mem
end

def fetch_windows
  mem_data = `systeminfo | findstr /C:"Total Physical Memory" /C:"Available Physical Memory"`
  mem = get_hash(mem_data)
  mem
end

def get_hash(data)
  mem = Hash.new
  unless data.nil?
    data.split("\n").each do |info|
      infos = info.split(':')
      mem[infos[0].to_s.strip] = {:memory_detail => infos[0].to_s.strip, :value => infos[1].to_s.strip}
    end
  end
  mem
end

def get_labels
  labels = [{:label => :memory_detail},
            {:label => :value}]
  labels
end