chromebrew/crew

#!/usr/bin/env ruby
require_relative 'lib/color'

# Disallow sudo
abort "Chromebrew should not be run as root.".lightred if Process.uid == 0

require 'find'
require 'net/http'
require 'uri'
require 'digest/sha2'
require 'json'
require 'fileutils'
require_relative 'lib/const'
require_relative 'lib/util'

# Add lib to LOAD_PATH
$LOAD_PATH.unshift "#{CREW_LIB_PATH}lib"

DOC = <<DOCOPT
Chromebrew - Package manager for Chrome OS http://skycocker.github.io/chromebrew/

Usage:
  crew build [-k|--keep] [-v|--verbose] <name> ...
  crew const [<name> ...]
  crew download [-v|--verbose] <name> ...
  crew files <name> ...
  crew help [<command>]
  crew install [-k|--keep] [-s|--build-from-source] [-S|--recursive-build] [-v|--verbose] <name> ...
  crew list (available|installed)
  crew remove [-v|--verbose] <name> ...
  crew search [-v|--verbose] [<name> ...]
  crew update
  crew upgrade [-k|--keep] [-s|--build-from-source] [-v|--verbose] [<name> ...]
  crew whatprovides <name> ...

  -k --keep               Keep the `CREW_BREW_DIR` (#{CREW_BREW_DIR}) directory.
  -s --build-from-source  Build from source even if pre-compiled binary exists.
  -S --recursive-build    Build from source, including all dependencies, even if pre-compiled binaries exist.
  -V --version            Display the crew version.
  -v --verbose            Show extra information.
  -h --help               Show this screen.

version #{CREW_VERSION}
DOCOPT

# Set XZ_OPT environment variable for build command.
# If CREW_XZ_OPT is defined, use it by default.  Use `-7e`, otherwise.
if ENV["CREW_XZ_OPT"].to_s == ''
  ENV["XZ_OPT"] = "-7e -T #{CREW_NPROC}"
else
  ENV["XZ_OPT"] = ENV["CREW_XZ_OPT"]
end

# Parse arguments using docopt
require_relative 'lib/docopt'
begin
  args = Docopt::docopt(DOC)
rescue Docopt::Exit => e
  if ARGV[0] then
    if ARGV[0] == '-V' or ARGV[0] == '--version' then
      puts "#{CREW_VERSION}"
      exit 0
    end
    if ARGV[0] != '-h' and ARGV[0] != '--help' then
      puts "Could not understand \"crew #{ARGV.join(' ')}\".".lightred
      cmds = ["build", "download", "files", "help", "install", "list", "remove", "search", "update", "upgrade", "whatprovides"]
      # Looking for similar commands
      if not cmds.include?(ARGV[0]) then
        similar = cmds.select {|word| edit_distance(ARGV[0], word) < 4}
        if not similar.empty? then
          puts "Did you mean?"
          similar.each {|sug| puts "  #{sug}"}
        end
      end
    end
  end
  puts e.message
  exit 1
end

@opt_keep = args["--keep"]
@opt_verbose = args["--verbose"]
@opt_src = args["--build-from-source"]
@opt_recursive = args["--recursive-build"]

@device = JSON.parse(File.read(CREW_CONFIG_PATH + 'device.json'), symbolize_names: true)
#symbolize also values
@device.each do |key, elem|
  @device[key] = @device[key].to_sym rescue @device[key]
end

def print_package(pkgName, extra = false)
  search pkgName, true
  print '(i) '.lightgreen if @device[:installed_packages].any? do |elem|
    elem[:name] == pkgName
  end
  print @pkg.name
  print ": #{@pkg.description}" if @pkg.description
  if extra
    puts ""
    puts @pkg.homepage if @pkg.homepage
    print "version #{@pkg.version}"
  end
  puts ""
end

def set_package (pkgName, silent = false)
  require CREW_LIB_PATH + 'packages/' + pkgName
  @pkg = Object.const_get(pkgName.capitalize)
  @pkg.build_from_source = true if @opt_recursive
  @pkg.name = pkgName
  print_package(pkgName, true) unless silent
end

def list_packages
  Find.find (CREW_LIB_PATH + 'packages') do |filename|
    if File.extname(filename) == '.rb'
      print_package File.basename filename, '.rb'
    end
  end
end

def list_available
  Find.find (CREW_LIB_PATH + 'packages') do |filename|
    @notInstalled = true
    Find.find(CREW_CONFIG_PATH + 'meta/') do |packageList|
      packageName = File.basename filename, '.rb'
      @notInstalled = nil if packageList == CREW_CONFIG_PATH + 'meta/' + packageName + '.filelist'
    end
    puts File.basename filename, '.rb' if File.extname(filename) == '.rb' if @notInstalled
  end
end

def list_installed
  Find.find (CREW_LIB_PATH + 'packages') do |filename|
    Find.find(CREW_CONFIG_PATH + 'meta/') do |packageList|
      packageName = File.basename filename, '.rb'
      if packageList == CREW_CONFIG_PATH + 'meta/' + packageName + '.filelist'
        puts File.basename filename, '.rb' if File.extname(filename) == '.rb'
      end
    end
  end
end

def search (pkgName, silent = false)
  Find.find (CREW_LIB_PATH + 'packages') do |filename|
    return set_package(pkgName, silent) if filename == CREW_LIB_PATH + 'packages/' + pkgName + '.rb'
  end
  abort "Package #{pkgName} not found. :(".lightred unless silent
end

def regexp_search(pkgName)
  results = Dir["#{CREW_LIB_PATH}packages/*.rb"].sort \
    .select  { |f| File.basename(f, '.rb') =~ Regexp.new(pkgName, true) } \
    .collect { |f| File.basename(f, '.rb') } \
    .each    { |f| print_package(f, @opt_verbose) }
  if results.empty?
    Find.find ("#{CREW_LIB_PATH}packages/") do |packageName|
      if File.file? packageName
        package = File.basename packageName, '.rb'
        search package, true
        if ( @pkg.description =~ /#{pkgName}/i )
          print_package(package, @opt_verbose)
          results.push(package)
        end
      end
    end
  end
  abort "Package #{pkgName} not found. :(".lightred unless results.length > 0
end

def help (pkgName)
  case pkgName
  when "build"
    puts "Build package(s)."
    puts "Usage: crew build [-k|--keep] [-v|--verbose] <package1> [<package2> ...]"
    puts "Build package(s) from source and place the archive and checksum in the current working directory."
    puts "If `-k` or `--keep` is present, the `CREW_BREW_DIR` (#{CREW_BREW_DIR}) directory will remain."
    puts "If `-v` or `--verbose` is present, extra information will be displayed."
  when "const"
    puts "Display constant(s)."
    puts "Usage: crew const [<const1> <const2> ...]"
    puts "If no constants are provided, all constants will be displayed."
  when "download"
    puts "Download package(s)."
    puts "Usage: crew download [-v|--verbose] <package1> [<package2> ...]"
    puts "Download package(s) to `CREW_BREW_DIR` (#{CREW_BREW_DIR}), but don't install."
    puts "If `-v` or `--verbose` is present, extra information will be displayed."
  when "files"
    puts "Display installed files of package(s)."
    puts "Usage: crew files <package1> [<package2> ...]"
    puts "The package(s) must be currently installed."
  when "install"
    puts "Install package(s)."
    puts "Usage: crew install [-k|--keep] [-s|--build-from-source] [-S|--recursive-build] [-v|--verbose] <package1> [<package2> ...]"
    puts "The package(s) must have a valid name.  Use `crew search <pattern>` to search for packages to install."
    puts "If `-k` or `--keep` is present, the `CREW_BREW_DIR` (#{CREW_BREW_DIR}) directory will remain."
    puts "If `-s` or `--build-from-source` is present, the package(s) will be compiled instead of installed via binary."
    puts "If `-S` or `--recursive-build` is present, the package(s), including all dependencies, will be compiled instead of installed via binary."
    puts "If `-v` or `--verbose` is present, extra information will be displayed."
  when "list"
    puts "List available or installed packages"
    puts "Usage: crew list (available|installed)"
  when "remove"
    puts "Remove package(s)."
    puts "Usage: crew remove [-v|--verbose] <package1> [<package2> ...]"
    puts "The package(s) must be currently installed."
    puts "If `-v` or `--verbose` is present, extra information will be displayed."
  when "search"
    puts "Look for package(s)."
    puts "Usage: crew search [-v|--verbose] [<pattern> ...]"
    puts "If <pattern> is omitted, all packages will be returned."
    puts "(i)".lightgreen + " in front of the name means the package is installed."
    puts "The <pattern> string can also contain regular expressions."
    puts "If `-v` or `--verbose` is present, homepage and version will be displayed."
    puts "Examples:"
    puts "  crew search | grep '(i)'".lightblue + " will display all installed packages."
    puts "  crew search | grep -v '(i)'".lightblue + " will display all available packages not already installed."
    puts "  crew search ^lib".lightblue + " will display all packages that start with `lib`."
    puts "  crew search audio".lightblue + " will display all packages with `audio` in the description."
    puts "  crew search git -v".lightblue + " will display packages with `git` in the name along with homepage and version."
  when "update"
    puts "Update crew."
    puts "Usage: crew update"
    puts "This only updates crew itself.  Use `crew upgrade` to update packages."
  when "upgrade"
    puts "Update package(s)."
    puts "Usage: crew upgrade [-v|--verbose] [-s|--build-from-source] <package1> [<package2> ...]"
    puts "If package(s) are omitted, all packages will be updated.  Otherwise, specific package(s) will be updated."
    puts "Use `crew update` to update crew itself."
    puts "If `-s` or `--build-from-source` is present, the package(s) will be compiled instead of upgraded via binary."
    puts "If `-v` or `--verbose` is present, extra information will be displayed."
  when "whatprovides"
    puts "Determine which package(s) contains file(s)."
    puts "Usage: crew whatprovides <pattern> ..."
    puts "The <pattern> is a search string which can contain regular expressions."
  else
    puts "Available commands: build, const, download, files, install, list ,remove, search, update, upgrade, whatprovides"
  end
end

def const (var)
  if var
    value = eval(var)
    puts "#{var}=#{value}"
  else
    vars = [
      'ARCH',
      'ARCH_LIB',
      'CHROMEOS_RELEASE',
      'CREW_BREW_DIR',
      'CREW_CONFIG_PATH',
      'CREW_DEST_DIR',
      'CREW_DEST_HOME',
      'CREW_DEST_LIB_PREFIX',
      'CREW_DEST_PREFIX',
      'CREW_LIB_PATH',
      'CREW_LIB_PREFIX',
      'CREW_NOT_COMPRESS',
      'CREW_NOT_STRIP',
      'CREW_NPROC',
      'CREW_PREFIX',
      'CREW_VERSION',
      'USER'
    ]
    vars.each { |var|
      value = eval(var)
      puts "#{var}=#{value}"
    }
  end
end

def files (pkgName)
  filelist = "#{CREW_PREFIX}/etc/crew/meta/#{pkgName}.filelist"
  if File.exists? "#{filelist}"
    system "sort #{filelist}"
    lines = `wc -l "#{filelist}"`.strip.split(' ')[0].to_i
    size = `du -ch $(cat #{filelist}) | tail -1 | cut -f 1`
    puts "Total found: #{lines}".lightgreen
    puts "Disk usage: #{size}".lightgreen
  else
    puts "Package #{pkgName} is not installed. :(".lightred
  end
end

def whatprovides (pkgName)
  fileArray = []
  Find.find (CREW_CONFIG_PATH + 'meta/') do |packageList|
    if File.file? packageList
      if packageList[/\.filelist$/]
        packageName = File.basename packageList, '.filelist'
        File.readlines(packageList).each do |line|
          found = line[/#{Regexp.new(pkgName)}/]
          if found
            fileLine = packageName + ': ' + line
            if not fileArray.include? fileLine
              fileArray.push(fileLine)
            end
          end
        end
      end
    end
  end
  if not fileArray.empty?
    fileArray.sort.each do |item|
      puts item
    end
    puts "\nTotal found: #{fileArray.length}".lightgreen
  end
end

def update
  abort "`crew update` is used to update crew itself. Use `crew upgrade <package1> [<package2> ...]` to update specific packages.".orange if @pkgName

  #update package lists
  Dir.chdir CREW_LIB_PATH do
    system "git fetch origin master"
    system "git reset --hard origin/master"
  end
  puts "Package lists, crew, and library updated."

  #check for outdated installed packages
  puts "Checking for package updates..."
  puts ""

  canBeUpdated = 0
  @device[:installed_packages].each do |package|
    search package[:name], true
    if package[:version] != @pkg.version
      canBeUpdated += 1
      puts @pkg.name + " could be updated from " + package[:version] + " to " + @pkg.version
    end
  end

  if canBeUpdated > 0
    puts ""
    puts "Run `crew upgrade` to update all packages or `crew upgrade <package1> [<package2> ...]` to update specific packages."
  else
    puts "Your software is up to date.".lightgreen
  end
end

def upgrade
  if @pkgName
    currentVersion = nil
    @device[:installed_packages].each do |package|
      if package[:name] == @pkg.name
        currentVersion = package[:version]
      end
    end

    if currentVersion != @pkg.version
      puts "Updating #{@pkg.name}..."
      @pkg.in_upgrade = true
      resolve_dependencies_and_install
      @pkg.in_upgrade = false
    else
      puts "#{@pkg.name} is already up to date.".lightgreen
    end
  else
    # Make a installed packages list belong to the dependency order
    dependencies = []
    @device[:installed_packages].each do |package|
      # skip package if it is dependent other packages previously checked
      next if dependencies.include? package[:name]
      # add package itself
      dependencies = [ package[:name] ].concat(dependencies)
      # expand depencencies and add it to the dependencies list
      search package[:name], true
      exp_dep = expand_dependencies
      dependencies = exp_dep.concat(dependencies)
    end
    dependencies.uniq!

    # Check version number of installed package and make a target list
    toBeUpdated = []
    dependencies.each do |dep|
      package = @device[:installed_packages].find {|pkg| pkg[:name] == dep}
      next unless package
      search package[:name], true
      if package[:version] != @pkg.version
        toBeUpdated.push(package[:name])
      end
    end

    if toBeUpdated.length > 0
      puts "Updating packages..."
      toBeUpdated.each do |package|
        search package
        puts "Updating " + @pkg.name + "..." if @opt_verbose
        @pkg.in_upgrade = true
        resolve_dependencies_and_install
        @pkg.in_upgrade = false
      end
      puts "Packages have been updated.".lightgreen
    else
      puts "Your software is already up to date.".lightgreen
    end
  end
end

def download
  url = @pkg.get_url(@device[:architecture])
  source = @pkg.is_source?(@device[:architecture])

  if !url
    abort "No precompiled binary or source is available for #{@device[:architecture]}.".lightred
  elsif !source
    puts "Precompiled binary available, downloading..."
  elsif @pkg.build_from_source
    puts "Downloading source..."
  else
    puts "No precompiled binary available for your platform, downloading source..."
  end

  uri = URI.parse url
  filename = File.basename(uri.path)
  if source
    sha256sum = @pkg.source_sha256
  else
    sha256sum = @pkg.binary_sha256[@device[:architecture]]
  end
  Dir.chdir CREW_BREW_DIR do
    if @opt_verbose then
      system('curl', '-v', '-C', '-', '--insecure', '-L', '-#', url, '-o', filename)
    else
      system('curl', '-s', '-C', '-', '--insecure', '-L', '-#', url, '-o', filename)
    end
    abort 'Checksum mismatch. :/ Try again.'.lightred unless
      Digest::SHA256.hexdigest( File.read("./#{filename}") ) == sha256sum
  end
  puts "Archive downloaded".lightgreen
  return {source: source, filename: filename}
end

def unpack (meta)
  extract_dir = "#{meta[:filename]}.dir"
  target_dir = nil
  Dir.chdir CREW_BREW_DIR do
    puts "Unpacking archive, this may take awhile..."
    Dir.mkdir("#{extract_dir}") unless Dir.exist?("#{extract_dir}")
    case File.extname meta[:filename]
    when '.zip'
      if @opt_verbose then
        system "unzip", "-v", "-d", "#{extract_dir}", meta[:filename]
      else
        system "unzip", "-qq", "-d", "#{extract_dir}", meta[:filename]
      end
    else
      if @opt_verbose then
        system "tar", "xvf", meta[:filename], "-C", "#{extract_dir}"
      else
        system "tar", "xf", meta[:filename], "-C", "#{extract_dir}"
      end
    end
    if meta[:source] == true
      # Check the number of directories in the archive
      entries = Dir["#{extract_dir}/*"]
      entries = Dir["#{extract_dir}/."] if entries.empty?
      if entries.length == 0
        abort "Empty archive: #{meta[:filename]}".lightred
      elsif entries.length == 1 && File.directory?(entries.first)
        # Use `extract_dir/dir_in_archive` if there is only one directory.
        target_dir = entries.first
      else
        # Use `extract_dir` otherwise
        target_dir = extract_dir
      end
    else
      # Use `extract_dir` for binary distribution
      target_dir = extract_dir
    end
  end
  return CREW_BREW_DIR + target_dir
end

def build_and_preconfigure (target_dir)
  Dir.chdir target_dir do
    puts "Building from source, this may take a while..."    

    # Rename *.la files temporily to *.la_tmp to avoid
    # libtool: link: '*.la' is not a valid libtool archive.
    # See https://gnunet.org/faq-la-files and
    # https://stackoverflow.com/questions/42963653/libquadmath-la-is-not-a-valid-libtool-archive-when-configuring-openmpi-with-g
    puts "Rename all *.la files to *.la_tmp".lightblue
    if @opt_verbose then
      system "find #{CREW_LIB_PREFIX} -type f -name *.la -print0 | xargs --null -I{} mv {} {}_tmp"
    else
      system "find #{CREW_LIB_PREFIX} -type f -name *.la -print0 | xargs --null -I{} mv {} {}_tmp"
    end

    @pkg.in_build = true
    @pkg.preinstall
    @pkg.patch
    @pkg.build
    @pkg.in_build = false
    # wipe crew destdir
    if @opt_verbose then
      system "rm -rvf #{CREW_DEST_DIR}/*"
    else
      system "rm -rf #{CREW_DEST_DIR}/*"
    end
    puts "Preconfiguring package..."
    @pkg.install

    # Rename all *.la_tmp back to *.la to avoid
    # cannot access '*.la': No such file or directory
    puts "Rename all *.la_tmp files back to *.la".lightblue
    if @opt_verbose then
      system "find #{CREW_LIB_PREFIX} -type f -name '*.la_tmp' -exec sh -c 'mv \"$1\" \"${1%.la_tmp}.la\"' _  {} \\;"
    else
      system "find #{CREW_LIB_PREFIX} -type f -name '*.la_tmp' -exec sh -c 'mv \"$1\" \"${1%.la_tmp}.la\"' _  {} \\;"
    end
  end
end

def post_install (dest_dir)
  Dir.chdir dest_dir do
    puts "Performing post-install..."
    @pkg.postinstall
  end
end

def compress_doc (dir)
  # check whether crew should compress
  return if CREW_NOT_COMPRESS || ENV['CREW_NOT_COMPRESS'] || !File.exist?("#{CREW_PREFIX}/bin/compressdoc")

  if Dir.exist? dir
    system "find #{dir} -type f ! -perm -200 | xargs -r chmod u+w"
    if @opt_verbose then
      system "compressdoc -v --gzip -9 #{dir}"
    else
      system "compressdoc --gzip -9 #{dir}"
    end
  end
end

def prepare_package (destdir)
  Dir.chdir destdir do
    # compress manual files
    compress_doc "#{destdir}#{CREW_PREFIX}/man"
    compress_doc "#{destdir}#{CREW_PREFIX}/info"
    compress_doc "#{destdir}#{CREW_PREFIX}/share/man"
    compress_doc "#{destdir}#{CREW_PREFIX}/share/info"

    # create directory list
    system "find . -type f > ../filelist"
    system "find . -type l >> ../filelist"
    system "cut -c2- ../filelist > filelist"

    # create file list
    system "find . -type d > ../dlist"
    system "cut -c2- ../dlist > dlistcut"
    system "tail -n +2 dlistcut > dlist"

    # remove temporary files
    if @opt_verbose then
      system "rm -vf dlistcut ../dlist ../filelist"
    else
      system "rm -f dlistcut ../dlist ../filelist"
    end
  end
end

def strip_find_files (find_cmd, strip_option = "")
  # check whether crew should strip
  return if CREW_NOT_STRIP || ENV['CREW_NOT_STRIP'] || !File.exist?("#{CREW_PREFIX}/bin/strip")

  # run find_cmd and strip only ar or ELF files
  system "#{find_cmd} | xargs -r chmod u+w"
  system "#{find_cmd} | xargs -r sh -c 'for i in \"$0\" \"$@\"; do case \"$(head -c 4 $i)\" in ?ELF|\!?ar) echo \"$i\";; esac ; done' | xargs -r strip #{strip_option}"
end

def install_package (pkgdir)
  Dir.chdir pkgdir do
    FileUtils.mv 'dlist', CREW_CONFIG_PATH + "meta/#{@pkg.name}.directorylist"
    FileUtils.mv 'filelist', CREW_CONFIG_PATH + "meta/#{@pkg.name}.filelist"

    # Strip libraries with -S
    strip_find_files "find . -type f -name 'lib*.a' -print", "-S"
    strip_find_files "find . -type f -name 'lib*.so*' -print", "-S"

    # Strip binaries but not compressed archives
    strip_find_files "find . -type f ! -iname '*\.bz2' ! -iname '*\.gz' ! -iname '*\.lha' ! -iname '*\.lz' ! -iname '*\.rar' ! -iname '*\.tar' ! -iname '*\.tgz' ! -iname '*\.xz' ! -iname '*\.zip' -perm /111 -print | sed -e '/lib.*\.a$/d' -e '/lib.*\.so/d'"

    if @opt_verbose then
      system "tar cvf - ./usr/* | (cd /; tar xp --keep-directory-symlink -f -)"
    else
      system "tar cf - ./usr/* | (cd /; tar xp --keep-directory-symlink -f -)"
    end
  end
end

def resolve_dependencies_and_install
  begin
    origin = @pkg.name

    resolve_dependencies

    search origin, true
    install
  rescue InstallError => e
    abort "#{@pkg.name} failed to install: #{e.to_s}".lightred
  ensure
    # cleanup
    unless @opt_keep
      Dir.chdir CREW_BREW_DIR do
        if @opt_verbose then
          system "rm -rvf *"
        else
          system "rm -rf *"
        end
        system "mkdir dest" # this is a little ugly, feel free to find a better way
      end
    end
  end
  puts "#{@pkg.name.capitalize} installed!".lightgreen
end

def expand_dependencies
  @dependencies = []

  def push_dependencies
    if @pkg.is_binary?(@device[:architecture]) ||
       (!@pkg.in_upgrade && !@pkg.build_from_source && @device[:installed_packages].any? { |pkg| pkg[:name] == @pkg.name })
      # retrieve name of dependencies that doesn't contain :build tag
      check_deps = @pkg.dependencies.select {|k, v| !v.include?(:build)}.map {|k, v| k}
    elsif @pkg.is_fake?
      # retrieve name of all dependencies
      check_deps = @pkg.dependencies.map {|k, v| k}
    else
      # retrieve name of all dependencies
      check_deps = @pkg.dependencies.map {|k, v| k}
    end

    # remove a dependent package which is equal to the target
    check_deps.select! {|name| @pkgName != name}

    # add new dependencies at the beginning of array
    @dependencies = check_deps.clone.concat(@dependencies)

    # check all dependencies recursively
    check_deps.each do |dep|
      search dep, true
      push_dependencies
    end
  end

  push_dependencies

  @dependencies.uniq
end

def resolve_dependencies
  dependencies = expand_dependencies

  # leave only not installed packages in dependencies
  dependencies.select! {|name| @device[:installed_packages].none? {|pkg| pkg[:name] == name}}

  return if dependencies.empty?

  puts "The following packages also need to be installed: "

  dependencies.each do |dep|
    print dep + " "
  end

  puts ""
  print "Do you agree? [Y/n] "
  response = STDIN.getc
  case response
  when "n"
    abort "No changes made."
  when "\n", "y", "Y"
    puts "Proceeding..."
    proceed = true
  else
    puts "I don't understand `#{response}`. :(".lightred
    abort "No changes made."
  end

  if proceed
    dependencies.each do |dep|
      search dep
      install
    end
  end
end

def install
  if !@pkg.in_upgrade && @device[:installed_packages].any? { |pkg| pkg[:name] == @pkg.name }
    puts "Package #{@pkg.name} already installed, skipping...".lightgreen
    return
  end

  unless @pkg.is_fake?
    meta = download
    target_dir = unpack meta
    if meta[:source] == true
      abort "You don't have a working C compiler. Run `crew install buildessential` to get one and try again.".lightred unless system("gcc", "--version")

      # build from source and place binaries at CREW_DEST_DIR
      # CREW_DEST_DIR contains usr/local/... hierarchy
      build_and_preconfigure target_dir

      # prepare filelist and dlist at CREW_DEST_DIR
      prepare_package CREW_DEST_DIR

      # use CREW_DEST_DIR
      dest_dir = CREW_DEST_DIR
    else
      # use extracted binary directory
      dest_dir = target_dir
    end

    # remove it just before the file copy
    if @pkg.in_upgrade
      puts "Removing since upgrade..."
      remove @pkg.name
    end

    # install filelist, dlist and binary files
    puts "Installing..."
    install_package dest_dir

    # perform post-install process
    post_install dest_dir
  end

  #add to installed packages
  @device[:installed_packages].push(name: @pkg.name, version: @pkg.version)
  File.open(CREW_CONFIG_PATH + 'device.json', 'w') do |file|
    output = JSON.parse @device.to_json
    file.write JSON.pretty_generate(output)
  end
end

def resolve_dependencies_and_build
  begin
    origin = @pkg.name

    # mark current package as which is required to compile from source
    @pkg.build_from_source = true
    resolve_dependencies

    search origin, true
    build_package Dir.pwd
  rescue InstallError => e
    abort "#{@pkg.name} failed to build: #{e.to_s}".lightred
  ensure
    #cleanup
    unless @opt_keep
      Dir.chdir CREW_BREW_DIR do
        if @opt_verbose then
          system "rm -rvf *"
        else
          system "rm -rf *"
        end
        system "mkdir dest" #this is a little ugly, feel free to find a better way
      end
    end
  end
  puts "#{@pkg.name} is built!".lightgreen
end

def build_package (pwd)
  abort "It is not possible to build a fake package".lightred if @pkg.is_fake?
  abort "It is not possible to build without source".lightred if !@pkg.is_source?(@device[:architecture])

  # download source codes and unpack it
  meta = download
  target_dir = unpack meta

  # build from source and place binaries at CREW_DEST_DIR
  build_and_preconfigure target_dir

  # call check method here.  this check method is called by this function only,
  # therefore it is possible place time consuming tests in the check method.
  if Dir.exist? target_dir
    Dir.chdir target_dir do
      puts "Checking..."
      @pkg.check
    end
  end

  # prepare filelist and dlist at CREW_DEST_DIR
  prepare_package CREW_DEST_DIR

  # build package from filelist, dlist and binary files in CREW_DEST_DIR
  puts "Archiving..."
  archive_package pwd
end

def archive_package (pwd)
  pkg_name = "#{@pkg.name}-#{@pkg.version}-chromeos-#{@device[:architecture]}.tar.xz"
  Dir.chdir CREW_DEST_DIR do
    if @opt_verbose then
      system "tar cJvf #{pwd}/#{pkg_name} *"
    else
      system "tar cJf #{pwd}/#{pkg_name} *"
    end
  end
  Dir.chdir pwd do
    system "sha256sum #{pkg_name} > #{pkg_name}.sha256"
  end
end

def remove (pkgName)

  #make sure the package is actually installed
  unless @device[:installed_packages].any? { |pkg| pkg[:name] == pkgName }
    puts "Package #{pkgName} isn't installed.".lightred
    return
  end

  #if the filelist exists, remove the files and directories installed by the package
  if File.file?("#{CREW_CONFIG_PATH}meta/#{pkgName}.filelist")
    Dir.chdir CREW_CONFIG_PATH do

      #remove all files installed by the package
      File.open("meta/#{pkgName}.filelist").each_line do |line|
        begin
          puts "Removing file " + line.chomp + "".lightred if @opt_verbose
          File.unlink line.chomp
        rescue => exception #swallow exception
        end
      end

      #remove all directories installed by the package
      File.readlines("meta/#{pkgName}.directorylist").reverse.each do |line|
        begin
          puts "Removing directory " + line.chomp + "".lightred if @opt_verbose
          Dir.rmdir line.chomp
        rescue => exception #swallow exception
        end
      end

      #remove the file and directory list
      File.unlink "meta/#{pkgName}.filelist"
      File.unlink "meta/#{pkgName}.directorylist"

    end
  end

  #remove from installed packages
  puts "Removing package " + pkgName + "".lightred if @opt_verbose
  @device[:installed_packages].each do |elem|
    @device[:installed_packages].delete elem if elem[:name] == pkgName
  end

  #update the device manifest
  File.open(CREW_CONFIG_PATH + 'device.json', 'w') do |file|
    out = JSON.parse @device.to_json
    file.write JSON.pretty_generate(out)
  end

  puts "#{pkgName.capitalize} removed!".lightgreen

end

def build_command (args)
  args["<name>"].each do |name|
    @pkgName = name
    search @pkgName
    resolve_dependencies_and_build
  end
end

def download_command (args)
  args["<name>"].each do |name|
    @pkgName = name
    search @pkgName
    download
  end
end

def const_command (args)
  unless args["<name>"].empty?
    args["<name>"].each do |name|
      const name
    end
  else
    const nil
  end
end

def files_command (args)
  args["<name>"].each do |name|
    @pkgName = name
    search @pkgName
    files name
  end
end

def help_command (args)
  if args["<command>"]
    help args["<command>"]
  else
    puts "Usage: crew help <command>"
    help nil
  end
end

def install_command (args)
  args["<name>"].each do |name|
    @pkgName = name
    search @pkgName
    @pkg.build_from_source = true if @opt_src or @opt_recursive
    resolve_dependencies_and_install
  end
end

def list_command (args)
  if args['available']
    list_available
  elsif args['installed']
    list_installed
  end
end

def remove_command (args)
  args["<name>"].each do |name|
    remove name
  end
end

def search_command (args)
  args["<name>"].each do |name|
    regexp_search name
  end.empty? and begin
    list_packages
  end
end

def update_command (args)
  update
end

def upgrade_command (args)
  args["<name>"].each do |name|
    @pkgName = name
    search @pkgName
    @pkg.build_from_source = true if @opt_src
    upgrade
  end.empty? and begin
    upgrade
  end
end

def whatprovides_command (args)
  args["<name>"].each do |name|
    whatprovides name
  end
end

def is_command (name)
  return false if name =~ /^[-<]/
  return true
end

command_name = args.find { |k, v| v && is_command(k) } [0]
function = command_name + "_command"
send(function, args)