#!/usr/bin/ruby
# This script installs to /usr/local only. To install elsewhere you can just
# untar https://github.com/mistydemeo/tigerbrew/tarball/master anywhere you like or
# change the value of HOMEBREW_PREFIX.
HOMEBREW_PREFIX = '/usr/local'

CURL_VERSION    = "7.58.0"
CURL_PPC_URL    = "http://archive.org/download/tigerbrew/portable-curl-#{CURL_VERSION}.tiger_g3.bottle.tar.gz"
CURL_PPC_SHA1   = "5bbd587871bca54637437359555618a4b1a612ec"
CURL_INTEL_URL  = "http://archive.org/download/tigerbrew/portable-curl-#{CURL_VERSION}.tiger_i386.bottle.tar.gz"
CURL_INTEL_SHA1 = "6e6e7989adb20856c0473aedecd623f443a6ac55"

module Tty extend self
  def blue; bold 34; end
  def white; bold 39; end
  def red; underline 31; end
  def reset; escape 0; end
  def bold n; escape "1;#{n}" end
  def underline n; escape "4;#{n}" end
  def escape n; "\033[#{n}m" if STDOUT.tty? end
end

class Array
  def shell_s
    cp = dup
    first = cp.shift
    cp.map{ |arg| arg.gsub " ", "\\ " }.unshift(first) * " "
  end
end

def ohai *args
  puts "#{Tty.blue}==>#{Tty.white} #{args.shell_s}#{Tty.reset}"
end

def warn warning
  puts "#{Tty.red}Warning#{Tty.reset}: #{warning.chomp}"
end
 
def system *args
  abort "Failed during: #{args.shell_s}" unless Kernel.system *args
end

def which cmd
  dir = ENV['PATH'].split(':').find {|p| File.executable? File.join(p, cmd)}
  File.join(dir, cmd) unless dir.nil?
end

def sudo *args
  args = if args.length > 1
    args.unshift "/usr/bin/sudo"
  else
    "/usr/bin/sudo #{args.first}"
  end
  ohai *args
  system *args
end

def getc  # NOTE only tested on OS X
  system "/bin/stty raw -echo"
  if RUBY_VERSION >= '1.8.7'
    STDIN.getbyte
  else
    STDIN.getc
  end
ensure
  system "/bin/stty -raw echo"
end

def wait_for_user
  puts
  puts "Press ENTER to continue or any other key to abort"
  c = getc
  # we test for \r and \n because some stuff does \r instead
  abort unless c == 13 or c == 10
end

def macos_version
  @macos_version ||= /(10\.\d+)(\.\d+)?/.match(`/usr/bin/sw_vers -productVersion`).captures.first.to_f
end

def git
  return if macos_version < 10.9

  @git ||= if ENV['GIT'] and File.executable? ENV['GIT']
    ENV['GIT']
  elsif which 'git'
    'git'
  end

  return unless @git
  # Github only supports HTTPS fetches on 1.7.10 or later:
  # https://help.github.com/articles/https-cloning-errors
  `#{@git} --version` =~ /git version (\d\.\d+\.\d+)/
  return if $1 < "1.7.10"

  @git
end

# Using curl to fetch curl, what could go wrong?
def fetch_vendor_curl!
  if `uname -m`.chomp == "Power Macintosh"
    url = CURL_PPC_URL
    sha = CURL_PPC_SHA1
  else
    url = CURL_INTEL_URL
    sha = CURL_INTEL_SHA1
  end

  # -k because the cert bundle can't verify archive.org, but
  # at least we speak its TLS standard.
  system "/usr/bin/curl", "-Lk", url, "-o", "/tmp/curl.tar.gz"
  our_hash = `openssl sha1 /tmp/curl.tar.gz`.chomp.split(" ").last
  if our_hash != sha
    abort <<-EOABORT
Unable to verify the integrity of the downloaded curl utility.
Downloaded file's SHA1 is #{our_hash} but the expected hash is
#{sha}.
    EOABORT
  end

  Dir.chdir "/tmp" do
    system "tar", "-xzf", "curl.tar.gz", "--strip", "1"
  end
end

def curl
  return @curl if defined? @curl

  fetch_vendor_curl!

  @curl = "/tmp/#{CURL_VERSION}/bin/curl"
end

# The block form of Dir.chdir fails later if Dir.CWD doesn't exist which I
# guess is fair enough. Also sudo prints a warning message for no good reason
Dir.chdir "/usr"

####################################################################### script
abort "Don't run this as root!" if Process.uid == 0
abort <<-EOABORT unless `groups`.split.include? "admin"
This script requires the user #{ENV['USER']} to be an Administrator. If this
sucks for you then you can install Homebrew in your home directory or however
you please; please refer to our homepage. If you still want to use this script
set your user to be an Administrator in System Preferences or `su' to a
non-root user with Administrator privileges.
EOABORT
abort <<-EOABORT unless Dir["#{HOMEBREW_PREFIX}/.git/*"].empty?
It appears Homebrew is already installed. If your intent is to reinstall you
should do the following before running this installer again:
    rm -rf #{HOMEBREW_PREFIX}/Cellar #{HOMEBREW_PREFIX}/.git && brew cleanup
EOABORT
# Tests will fail if the prefix exists, but we don't have execution
# permissions. Abort in this case.
abort <<-EOABORT if File.directory? HOMEBREW_PREFIX and not File.executable? HOMEBREW_PREFIX
The Homeprew prefix, #{HOMEBREW_PREFIX}, exists but is not searchable. If this is
not intentional, please restore the default permissions and try running the
installer again:
    sudo chmod 755 #{HOMEBREW_PREFIX}
EOABORT

ohai "This script will install:"
puts "#{HOMEBREW_PREFIX}/bin/brew"
puts "#{HOMEBREW_PREFIX}/Library/..."
puts "#{HOMEBREW_PREFIX}/share/man/man1/brew.1"

chmods = %w( . bin etc include lib lib/pkgconfig Library sbin share var var/log share/locale share/man
             share/man/man1 share/man/man2 share/man/man3 share/man/man4
             share/man/man5 share/man/man6 share/man/man7 share/man/man8
             share/info share/doc share/aclocal ).
            map{ |d| "#{HOMEBREW_PREFIX}/#{d}" }.
            select{ |d| File.directory? d and (not File.readable? d or not File.writable? d or not File.executable? d) }
chgrps = chmods.reject{ |d| File.stat(d).grpowned? }

unless chmods.empty?
  ohai "The following directories will be made group writable:"
  puts *chmods
end
unless chgrps.empty?
  ohai "The following directories will have their group set to #{Tty.underline 39}admin#{Tty.reset}:"
  puts *chgrps
end

wait_for_user if STDIN.tty?

if File.directory? HOMEBREW_PREFIX
  sudo "/bin/chmod", "g+rwx", *chmods unless chmods.empty?
  sudo "/usr/bin/chgrp", "admin", *chgrps unless chgrps.empty?
else
  sudo "/bin/mkdir #{HOMEBREW_PREFIX}"
  sudo "/bin/chmod g+rwx #{HOMEBREW_PREFIX}"
  # the group is set to wheel by default for some reason
  sudo "/usr/bin/chgrp admin #{HOMEBREW_PREFIX}"
end

ohai "Downloading and Installing Homebrew..."
Dir.chdir HOMEBREW_PREFIX do
  if git
    # we do it in four steps to avoid merge errors when reinstalling
    system git, "init", "-q"
    system git, "remote", "add", "origin", "https://github.com/mistydemeo/tigerbrew"

    args = git, "fetch", "origin", "master:refs/remotes/origin/master", "-n"
    args << "--depth=1" if ARGV.include? "--fast"
    system *args

    system git, "reset", "--hard", "origin/master"
  else
    # -m to stop tar erroring out if it can't modify the mtime for root owned directories
    curl_flags = "fsSL"
    system "/bin/bash -c '#{curl} -#{curl_flags} https://github.com/mistydemeo/tigerbrew/tarball/master | /usr/bin/tar xz -m --strip 1'"
  end
end

warn "#{HOMEBREW_PREFIX}/bin is not in your PATH." unless ENV['PATH'].split(':').include? "#{HOMEBREW_PREFIX}/bin"

if macos_version < 10.7
  warn "Now install Xcode: https://developer.apple.com/xcode/" unless File.exist? "/usr/bin/cc"
else
  `/usr/bin/cc --version 2> /dev/null` =~ %r[clang-(\d{2,})]
  version = $1.to_i
  warn %{Install the "Command Line Tools for Xcode": http://connect.apple.com} if version < 425
end

ohai "Installation successful!"
puts "You should run `brew doctor' *before* you install anything."
puts "Now type: brew help"