#  Copyright 2009 Max Howell <max@methylblue.com>
#
#  This file is part of Homebrew.
#
#  Homebrew is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#
#  Homebrew is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with Homebrew.  If not, see <http://www.gnu.org/licenses/>.
#
require 'pathname'

# we enhance pathname to make our code more readable
class Pathname
  def mv dst    
    FileUtils.mv to_s, dst
  end
  
  def rename newname
    raise unless file?
    dst=dirname+newname
    dst.unlink rescue nil
    mv dst
  end

  def install src
    if src.is_a? Array
      src.collect {|src| install src }
    elsif File.exist? src
      mkpath
      if File.symlink? src
        # we use the BSD mv command because FileUtils copies the target and
        # not the link! I'm beginning to wish I'd used Python quite honestly!
        raise unless Kernel.system 'mv', src, to_s and $? == 0
      else
        # we mv when possible as it is faster and you should only be using
        # this function when installing from the temporary build directory
        FileUtils.mv src, to_s
      end
      return self+src
    end
  end

  def cp dst
    if file?
      FileUtils.cp to_s, dst
    else
      FileUtils.cp_r to_s, dst
    end
  end

  # extended to support the double extensions .tar.gz and .tar.bz2
  def extname
    /(\.tar\.(gz|bz2))$/.match to_s
    return $1 if $1
    return File.extname(to_s)
  end

  # for filetypes we support, basename without extension
  def stem
    return File.basename(to_s, extname)
  end

  # I don't trust the children.length == 0 check particularly, not to mention
  # it is slow to enumerate the whole directory just to see if it is empty,
  # instead rely on good ol' libc and the filesystem
  def rmdir_if_possible
    rmdir
  rescue SystemCallError => e
    raise unless e.errno == Errno::ENOTEMPTY::Errno
  end
  
  def chmod_R perms
    require 'fileutils'
    FileUtils.chmod_R perms, to_s
  end

  def abv
    `find #{to_s} -type f | wc -l`.strip+' files, '+`du -hd0 #{to_s} | cut -d"\t" -f1`.strip
  end

  def version
    # github tarballs are special
    # we only support numbered tagged downloads
    %r[github.com/.*/tarball/((\d\.)+\d)$].match to_s
    return $1 if $1
    
    # eg. boost_1_39_0
    /((\d+_)+\d+)$/.match stem
    return $1.gsub('_', '.') if $1

    # eg. foobar-4.5.1-1
    /-((\d+\.)*\d+-\d+)$/.match stem
    return $1 if $1

    # eg. foobar-4.5.1
    /-((\d+\.)*\d+)$/.match stem
    return $1 if $1

    # eg. foobar-4.5.1b
    /-((\d+\.)*\d+([abc]|rc\d))$/.match stem
    return $1 if $1

    # eg foobar-4.5.0-beta1
    /-((\d+\.)*\d+-beta\d+)$/.match stem
    return $1 if $1

    # eg. foobar4.5.1
    /((\d+\.)*\d+)$/.match stem
    return $1 if $1

    # eg. otp_src_R13B (this is erlang's style)
    # eg. astyle_1.23_macosx.tar.gz
    stem.scan /_([^_]+)/ do |match|
      return match.first if /\d/.match $1
    end
  end
end

# sets $n and $d so you can observe creation of stuff
module ObserverPathnameExtension
  def unlink
    super
    puts "rm #{to_s}" if ARGV.verbose?
    $n+=1
  end
  def rmdir
    super
    puts "rmdir #{to_s}" if ARGV.verbose?
    $d+=1
  end
  def resolved_path_exists?
    (dirname+readlink).exist?
  end
  def mkpath
    super
    puts "mkpath #{to_s}" if ARGV.verbose?
    $d+=1
  end
  def make_relative_symlink src
    dirname.mkpath
    Dir.chdir dirname do
      # TODO use Ruby function so we get exceptions
      # NOTE Ruby functions may work, but I had a lot of problems
      rv=system 'ln', '-sf', src.relative_path_from(dirname)
      raise "Could not create symlink #{to_s}" unless rv and $? == 0
      puts "ln #{to_s}" if ARGV.verbose?
      $n+=1
    end
  end
end

$n=0
$d=0