#!/usr/bin/env ruby
require 'find'
require 'net/http'
require 'uri'
require 'digest/sha1'
require 'json'
require 'fileutils'

@command = ARGV[0]
@pkgName = ARGV[1]

ARCH = `uname -m`.strip
ARCH_LIB = if ARCH == 'x86_64' then 'lib64' else 'lib' end

CREW_PREFIX = '/usr/local'
CREW_LIB_PREFIX = CREW_PREFIX + '/' + ARCH_LIB

CREW_LIB_PATH = CREW_PREFIX + '/lib/crew/'
CREW_CONFIG_PATH = CREW_PREFIX + '/etc/crew/'
CREW_BREW_DIR = CREW_PREFIX + '/tmp/crew/'
CREW_DEST_DIR = CREW_BREW_DIR + 'dest'

# Set CREW_NPROC from environment variable or `nproc`
if ENV["CREW_NPROC"].to_s == ''
  CREW_NPROC = `nproc`.strip
else
  CREW_NPROC = ENV["CREW_NPROC"]
end

# Set CREW_NOT_STRIP from environment variable
CREW_NOT_STRIP = ENV["CREW_NOT_STRIP"]

# 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"
else
  ENV["XZ_OPT"] = ENV["CREW_XZ_OPT"]
end

$LOAD_PATH.unshift "#{CREW_LIB_PATH}lib"

USER = `whoami`.chomp

# colorization
class String
  def colorize(color_code, shade)
    "\e[#{shade};#{color_code}m#{self}\e[0m"
  end

  def black
    colorize(30, 0)
  end

  def red
    colorize(31, 0)
  end

  def green
    colorize(32, 0)
  end

  def orange
    colorize(33, 0)
  end

  def blue
    colorize(34, 0)
  end

  def purple
    colorize(35, 0)
  end

  def cyan
    colorize(36, 0)
  end

  def lightgray
    colorize(37, 0)
  end

  def gray
    colorize(30, 1)
  end

  def lightred
    colorize(31, 1)
  end

  def lightgreen
    colorize(32, 1)
  end

  def yellow
    colorize(33, 1)
  end

  def lightblue
    colorize(34, 1)
  end

  def lightpurple
    colorize(35, 1)
  end

  def lightcyan
    colorize(36, 1)
  end

  def white
    colorize(37, 1)
  end
end

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

@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
  Find.find(CREW_CONFIG_PATH + 'meta/') do |packageList|
    print '(i) '.lightgreen if packageList == CREW_CONFIG_PATH + 'meta/' + pkgName + '.filelist'
  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.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 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
end

def regexp_search(pkgName)
  results = Dir["#{CREW_LIB_PATH}packages/*.rb"] \
	  .select  { |f| File.basename(f, '.rb') =~ Regexp.new(pkgName, true) } \
	  .collect { |f| File.basename(f, '.rb') } \
	  .each    { |f| print_package(f, ARGV[2] == "extra") }
  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, ARGV[2] == "extra")
          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 a package."
    puts "Usage: crew build [package]"
    puts "Build [package] from source and place the archive and checksum in the current working directory."
  when "download"
    puts "Download a package."
    puts "Usage: crew download [package]"
    puts "Download [package] to `CREW_BREW_DIR` (`/usr/local/tmp/crew` by default), but don't install it."
  when "install"
    puts "Install a package."
    puts "Usage: crew install [package]"
    puts "The [package] must be a valid name.  Use `crew search [package]` to search for a package to install."
  when "remove"
    puts "Remove a package."
    puts "Usage: crew remove [package]"
    puts "The [package] must be currently installed."
  when "search"
    puts "Look for a package."
    puts "Usage: crew search [package] [extra]"
    puts "If [package] is omitted, all packages will be returned."
    puts "(i)".lightgreen + " in front of the name means the package is installed."
    puts "The [package] string can also contain regular expressions."
    puts "If the keyword 'extra' is appended, 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 extra".lightblue + " will display the git package 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 [package]"
    puts "If [package] is omitted, all packages will be updated.  Otherwise, a specific package will be updated."
    puts "Use 'crew update' to update crew itself."
  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, download, install, remove, search, update, upgrade, whatprovides"
  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 <packageName> to upgrade a specific package.".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 upgrade everything or 'crew upgrade <packageName>' to upgrade a specific package."
  else
    puts "Your software is up to date.".lightgreen
  end
end

def upgrade
  if @pkgName
    search @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
        @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 for #{@device[:architecture]} nor source is available.".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
    sha1sum = @pkg.source_sha1
    sha256sum = @pkg.source_sha256
  else
    sha1sum = @pkg.binary_sha1[@device[:architecture]]
    sha256sum = @pkg.binary_sha256[@device[:architecture]]
  end
  Dir.chdir CREW_BREW_DIR do
    system('wget', '--continue', '--no-check-certificate', url, '-O', filename)
    abort 'Checksum mismatch. :/ Try again.'.lightred unless
      Digest::SHA1.hexdigest( File.read("./#{filename}") ) == sha1sum or
      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 a while..."
    Dir.mkdir("#{extract_dir}") unless Dir.exist?("#{extract_dir}")
    if meta[:filename][-4,4] == ".zip"
      system "unzip", "-qq", "-d", "#{extract_dir}", meta[:filename]
    else
      system "tar", "xf", meta[:filename], "-C", "#{extract_dir}"
    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..."
    @pkg.in_build = true
    @pkg.build
    @pkg.in_build = false
    system "rm -rf #{CREW_DEST_DIR}/*" #wipe crew destdir
    puts "Preconfiguring package..."
    @pkg.install
  end
end

def prepare_package (destdir)
  Dir.chdir destdir do
    #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
    system "rm dlistcut ../dlist ../filelist"
  end
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
    system "find . -name 'lib*.a' -print | xargs chmod u+w 2>/dev/null" unless CREW_NOT_STRIP
    system "find . -name 'lib*.a' -print | xargs strip -S 2>/dev/null" unless CREW_NOT_STRIP
    system "find . -name 'lib*.so*' -print | xargs chmod u+w 2>/dev/null" unless CREW_NOT_STRIP
    system "find . -name 'lib*.so*' -print | xargs strip -S 2>/dev/null" unless CREW_NOT_STRIP

    # Strip binaries
    system "find . -type f -perm /111 -print | sed -e '/lib.*\.a$/d' -e '/lib.*\.so/d' | xargs chmod u+w 2>/dev/null" unless CREW_NOT_STRIP
    system "find . -type f -perm /111 -print | sed -e '/lib.*\.a$/d' -e '/lib.*\.so/d' | xargs strip 2>/dev/null" unless CREW_NOT_STRIP

    system "tar cf - ./usr/* | (cd /; tar xp --keep-directory-symlink -f -)"
  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 ARGV[2] == 'keep'
      Dir.chdir CREW_BREW_DIR do
        system "rm -rf *"
        system "mkdir dest" #this is a little ugly, feel free to find a better way
      end
    end
  end
end

def expand_dependencies
  @dependencies = []

  # check source packages existance
  @source_package = 0

  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}
      # count the number of source packages to add buildessential into dependencies later
      @source_package += 1
    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

  # Add buildessential's dependencies if any of dependent
  # packages are made from source
  if @source_package > 0
    search 'buildessential', true
    push_dependencies
  end
  @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
  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
  puts "#{@pkg.name.capitalize} installed!".lightgreen
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 ARGV[2] == 'keep'
      Dir.chdir CREW_BREW_DIR do
        system "rm -rf *"
        system "mkdir dest" #this is a little ugly, feel free to find a better way
      end
    end
  end
end

def build_package (pwd)
  abort "It is not possible to build 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
    system "tar cJf #{pwd}/#{pkg_name} *"
  end
  Dir.chdir pwd do
    system "sha1sum #{pkg_name} > #{pkg_name}.sha1"
    system "sha256sum #{pkg_name} > #{pkg_name}.sha256"
  end
  puts "#{pkg_name} is built!".lightgreen
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
          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
          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
  @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

case @command
when "help"
  if @pkgName
    help @pkgName
  else
    puts "Usage: crew help [command]"
    help nil
  end
when "search"
  if @pkgName
    regexp_search @pkgName
  else
    list_packages
  end
when "whatprovides"
  if @pkgName
    whatprovides @pkgName
  else
    help "whatprovides"
  end
when "download"
  if @pkgName
    search @pkgName
    download
  else
    help "download"
  end
when "update"
  update
when "upgrade"
  upgrade
when "install"
  if @pkgName
    search @pkgName
    resolve_dependencies_and_install
  else
    help "install"
  end
when "build"
  if @pkgName
    search @pkgName
    resolve_dependencies_and_build
  else
    help "build"
  end
when "remove"
  if @pkgName
    remove @pkgName
  else
    help "remove"
  end
when nil
  puts "Chromebrew, version 0.4.3"
  puts "Usage: crew [command] [package]"
  help nil
else
  puts "I have no idea how to do #{@command} :(".lightred
  help nil
end