#
# Rakefile to install kindlegen
# (c) Copryright Toshihiko Ichida 2016
#
require 'rbconfig'
require 'fileutils'

AMAZON = 'http://kindlegen.s3.amazonaws.com'
BINDIR = '../bin'

def create_default_task(target)
  task :default => :install

  task :install => target do |t|
    mkdir BINDIR unless File.exist?(BINDIR)
    cp t.source, BINDIR
  end
end

def create_task_for_unix(config)
  tarball = config[:tarball]
  unzip   = config[:unzip]
  target  = config[:target]
  url = "#{AMAZON}/#{tarball}"

  create_default_task(target)

  file target => tarball do
    sh "#{unzip} #{tarball}"
    sh "chmod +x #{target}"
  end

  file tarball do
    sh "curl #{url} -L -o #{tarball}"
  end
end

# curl for windows
def curl(url, tarball)
  puts "open(#{url})"
  puts "save to #{tarball}"
  data = open(url, 'rb').read
  open(tarball, 'wb').write(data)
end

# unzip for windows
def unzip(tarball)
  puts "win-unzip #{tarball}"
  Zip::File.open(tarball).each do |entry|
    dir = File.dirname(entry.name)
    FileUtils.mkpath(dir) if dir != '.' && !File.exist?(dir)
    entry.extract unless File.exist?(entry.name)
  end
end

def create_task_for_windows(config)
  require 'open-uri'
  require 'zip'

  tarball = config[:tarball]
  target  = config[:target]
  url = "#{AMAZON}/#{tarball}"

  create_default_task(target)

  file target => tarball do
    unzip(tarball)
  end

  file tarball do
    curl(url, tarball)
  end
end

case RbConfig::CONFIG['host_os']
when /mac|darwin/i
  create_task_for_unix(
    { tarball: 'KindleGen_Mac_i386_v2_9.zip',
      unzip:   'unzip',
      target:  'kindlegen' })
when /linux|cygwin/i
  create_task_for_unix(
    { tarball: 'kindlegen_linux_2.6_i386_v2_9.tar.gz',
      unzip:   'tar -zx --no-same-owner -f',
      target:  'kindlegen' })
when /mingw32|mswin32/i
  create_task_for_windows(
    { tarball: 'kindlegen_win32_v2_9.zip',
      target: 'kindlegen.exe' })
else
  STDERR.puts "Host OS unsupported!"
  exit(1)
end