#!/bin/bash

rvm_author="Wayne E. Seguin"
rvm_version="0.0.1"
rvm_updated="2009.08.23"

#
# License: See LICENSE
#

#
# Functions
#
function usage {

  cat <<-Usage

  Usage:

    $0 Action [Implementation] [Options]

  Action:

    install  - Install a ruby version, default is from source
    use      - Switch to using a specific ruby versio (new login shell)
    path     - Set path for current ruby
    info     - Show information for current ruby
    gemdir   - Switch to gem directory for installation (new login shell)
    gemdup   - Clone source implementation version gems to currently used version
    setup    - Place rvm to in default path (~/.bin/ && .profile)
    * usage  - Show this usage information

  Implementation:

    * ruby   - MRI/YARV Ruby (The Standard)
    jruby    - jRuby
    ree      - Ruby Enterprise Edition
    rubinius - Rubinius (NI)
    leopard  - Leopard's system Ruby ( Mac OS X only )
    default  - Resets to the default system ruby
  
  Options: 

    -v|--version    - Ruby Package Version, defaults to 'latest'
    -l|--level      - Patch level for the specified Ruby version
    -p|--prefix     - Package and source directory prefix, with trailing slash!
                      Default is a users home directory and /usr/local/ for root
    -m|--manager    - Package Manager to use, one of:
                      {port,aptitude,apt-get,emerge,yum,pacman}
    -d|--debug      - Toggle debug mode on

  Notes:

    * Defaults are denoted with a * prefix.

  TODO: (in order)

    * Rubinius (not in first revisions)
    * Shell detection instead of simply assuming bash (not in first revisions)

Usage

}

# Logging functions based on level
function log   { echo -e "\n $* \e[0m\n" ; }
function debug { log "\e[4;34m <d> $*" ; }
function info  { log "\e[0;32m <i> $*" ; }
function warn  { log "\e[0;33m <w> $*" ; }
function error { log "\e[0;31m <e> $*" ; }
function fail  { log "\e[0;31m <e> $*" ; }

function ruby-gi { gem install -q --no-rdoc --no-ri $* ; }

function ruby-info {

  full_version=$(ruby -v)
  ruby_implementation=$(echo "$full_version" | awk '{print $1}')
  ruby_version=$(echo "$full_version" | awk '{print $2}')
  ruby_patchlevel=$(echo "$full_version" | sed 's/^.*(//' | sed 's/).*$//')
  ruby_date=$(echo "$full_version" | sed 's/^.*(\([0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]\).*$/\1/')
  ruby_platform=$(echo "$full_version" | sed 's/^.*\[//' | sed 's/\].*$//')

  cat <<-Info
ruby:
  implementation: "$ruby_implementation"
  version:        "$ruby_version"
  date:           "$ruby_date"
  platform:       "$ruby_platform"
  patchlevel:     "$ruby_patchlevel"
  gem_home:       "${GEM_HOME-not set}"
  ruby_home:      "${ruby_home-not set}"
  full_version:   "$full_version"
Info

}

function ruby-install-source {

  case "${version-$1}" in
    1.9|1.9.1) major="1.9" ; minor="1" ; patchlevel="${2-243}" ;;
    1.8|1.8.6) major="1.8" ; minor="6" ; patchlevel="${2-369}" ;;
        1.8.7) major="1.8" ; minor="7" ; patchlevel="${2-174}" ;;
    *) fail "Ruby version '$version' is unknown."
  esac

  package_name="ruby-$major.$minor-p$patchlevel"
  url="ftp://ftp.ruby-lang.org/pub/ruby/$major/$package_name.tar.gz"
 
  pushd $source_path
  if [ -d $package_name ]  ; then
    cd $package_name
  else
    if [ ! -f "$package_name.tar.gz" ] ; then $curl $url ; fi
    tar xzf $package_name.tar.gz && cd $package_name/
  fi
  ./configure --prefix=$install_path/$package_name --enable-shared && make && make install 
  chmod +x $install_path/$package_name/bin/*
  popd

}

function ruby-install {

  case "$implementation" in
    leopard) # no-op
      system_type=`uname`
      if [ "$system_type" = "Darwin" ] ; then
        echo "Leopard ruby is not installable via rvm."
      else
        fail "leopard ruby is the default ruby installed on Mac OS X (Darwin), you are on: $system_type"
      fi
    ;;

    ree)
      version=${version-1.8.6}
      patchlevel=${patchlevel-20090610}
      package_name="ruby-enterprise-$version-$patchlevel"
      url="http://rubyforge.org/frs/download.php/58677/$package_name.tar.gz"
      pushd $source_path 
      if [ -d $package_name ]  ; then
        cd $package_name
      else
        if [ ! -f "$package_name.tar.gz" ] ; then $curl $url ; fi
        tar xzf $package_name.tar.gz && cd $package_name/
      fi
      cd ruby-enterprise-$version-$patchlevel && ./installer -a $install_path/ruby-enterprise-$version-$patchlevel --dont-install-useful-gems
      popd
      chmod +x $install_path/$package_name/bin/*
    ;;

    jruby)
      version=${version-1.3.1} # 1.2.0, 1.3.1
      patchlevel="" # No patchlevel for jRuby
      package_name="$implementation-bin-$version"
      package_dir="$implementation-$version"
      url="http://dist.codehaus.org/$implementation/$version/$package_name.zip"
      pushd $source_path
      if [ -d $package_name ]  ; then
        cd $package_name
      else
        if [ ! -f "$package_name.zip" ] ; then $curl $url ; fi
        jar xf $package_name.zip && cd $package_name/
      fi
      mkdir -p $install_path/$package_dir/bin/
      for binary in jruby jgem jirb ; do
        ln -sf $source_path/$package_dir/bin/$binary $source_path/$package_dir/bin/${binary#j}
      done
      rsync -ag $source_path/$package_dir/ $install_path/$package_dir/
      cd $source_path/$package_dir/tool/nailgun && make
      popd
      chmod +x $install_path/$package_dir/bin/*
      ruby-gi jruby-openssl
    ;;

    ruby)
      version=${version-1.8.6}
      ruby-install-source $version ${patchlevel-$3}
    ;;

    *) fail "Ruby implementation '$implementation' is not known."

  esac

  ruby-gi rake

  MY_RUBY_HOME=ruby_home
  export ruby_home GEM_HOME PATH MY_RUBY_HOME

}

function ruby-use {

  case "$implementation" in

    default)
      rm -f ~/.rvm/current
      unset ruby_home
      unset GEM_HOME
    ;;

    leopard)
      ruby_home="/System/Library/Frameworks/Ruby.framework/Versions/Current/usr"
      GEM_HOME="$HOME/.gem/ruby/1.8"
    ;;

    jruby)
      version="${version-1.3.1}"
      if [ "$version" = "1.2.0" -o "$version" = "1.3.1" ] ; then
        ruby_home="$install_path/jruby-$version"
        GEM_HOME="$HOME/.gem/jruby/1.8"
        alias ruby_ng="jruby --ng"
        alias ruby_ng_server="jruby --ng-server"
      else
        fail "Unknown jRuby version: $version"
      fi
    ;;

    ree)
      version=${version-1.8.6}
      if [ "$version" = "1.8.6" ] ; then
        patchlevel="${3-20090610}"
        ruby_home="$install_path/ruby-enterprise-$version-$patchlevel"
        GEM_HOME="$HOME/.gem/ruby-enterprise/1.8"
      else
        fail "Unknown Ruby Enterprise Edition version: $version"
      fi
    ;;

    ruby)
      if [ "$version" = "1.8.6" ] ; then
        patchlevel="${patchlevel-369}"
        ruby_home="$install_path/ruby-1.8.6-p$patchlevel"
        GEM_HOME="$HOME/.gem/ruby/1.8"
      elif [ "$version" = "1.8.7" ] ; then
        patchlevel="${patchlevel-174}"
        ruby_home="$install_path/ruby-1.8.7-p$patchlevel"
        GEM_HOME="$HOME/.gem/ruby/1.8"
      elif [ "$version" = "1.9.1" -o "$version" = "1.9" ] ; then
        patchlevel="${patchlevel-243}"
        ruby_home="$install_path/ruby-1.9.1-p$patchlevel"
        GEM_HOME="$HOME/.gem/ruby/1.9.1"
      else
        fail "Unknown ruby version: $version"
      fi
    ;;

    *)
      fail "Ruby implementation '$implementation' is not known."

  esac

  if [ ! "$implementation" = "default" ] ; then
    MY_RUBY_HOME=$ruby_home
    RUBY_VERSION="$($ruby_home/bin/ruby -v | sed 's/^\(.*\) (.*$/\1/')"
    export GEM_HOME ruby_home MY_RUBY_HOME RUBY_VERSION

    if [ ! -d $ruby_home ] ; then
      warn "$implementation $version is not installed, installing."
      ruby-install $implementation $version $patchlevel
    fi

    # Setup ~/.rvm/current
    echo "PATH=$ruby_home/bin:$GEM_HOME/bin:\$PATH ; export PATH" > ~/.rvm/current
    for variable in RUBY_VERSION GEM_HOME MY_RUBY_HOME ruby_home ; do
      eval "export $variable"
      eval value=\$${variable}
      echo "${variable}='$value' ; export ${variable}" >> ~/.rvm/current
    done
  else
    PATH=$original_path ; export PATH
  fi

  info "Switching to $implementation $version $patchlevel ..."
  exec bash --login

}
 
function ruby-gem-dir {

  case "$implementation" in
    leopard) GEM_HOME="$HOME/.gem/ruby/1.8"  ;;
    jruby)   GEM_HOME="$HOME/.gem/jruby/1.8" ;;
    ree)     GEM_HOME="$HOME/.gem/ruby-enterprise/1.8"  ;;
    ruby)
      if [ "$version" = "1.8.6" ] ; then
        GEM_HOME="$HOME/.gem/ruby/1.8"
      elif [ "$version" = "1.8.7" ] ; then
        GEM_HOME="$HOME/.gem/ruby/1.8"
      elif [ "$version" = "1.9.1" -o "$version" = "1.9" ] ; then
        GEM_HOME="$HOME/.gem/ruby/1.9.1"
      else
        fail "Unknown ruby version: $version"
      fi
    ;;
    *)
      fail "Ruby implementation '$implementation' is not known."
  esac
  cd $GEM_HOME

}

# clones from source implementation/version to current
function ruby-gem-dup {

  source_implementation=${1-ruby}
  source_version=${2-1.8.6}

  # TODO: use ruby-gem-dir for this once it has stabilized
  case "$source_implementation" in
    leopard) gemdir="$HOME/.gem/ruby/1.8"  ;;
    jruby)   gemdir="$HOME/.gem/jruby/1.8" ;;
    ree)     gemdir="$HOME/.gem/ruby-enterprise/1.8"  ;;
    ruby)
      if [ "$source_version" = "1.8.6" ] ; then
        gemdir="$HOME/.gem/ruby/1.8"
      elif [ "$source_version" = "1.8.7" ] ; then
        gemdir="$HOME/.gem/ruby/1.8"
      elif [ "$source_version" = "1.9.1" -o "$version" = "1.9" ] ; then
        gemdir="$HOME/.gem/ruby/1.9.1"
      fi
    ;;
  esac

  if [ ! -z "$gemdir" ] ; then
    for gem_name_version in `ls $gemdir/gems` ; do
      gem_name=${gem_name_version%-*}
      gem_version=${gem_name_version##*-}
      if [ -d $GEM_HOME/gems/$gem_name_version ] ; then
        echo "$gem_name_version already installed."
      else
        ruby-gi $gemdir/cache/$gem_name-$gem_version.gem
      fi
    done
  else
    fail "Unknown $implementation version: $version"
  fi

}

function rvm-setup {

  rm -f ~/.bin/rvm
  bindir=$(dirname `which rvm`)
  gemsdir="$(dirname $bindir)/gems"
  cd $gemsdir/`ls -t ~/.gem/ruby/1.8/gems | grep rvm | head -n 1`
  bash/rvm-setup

  info "~/.bin/rvm is symlinked to the gem's rvm script and ~/.bin is in your path.\n" \
       "You may now use rvm via the command line the next time you open a terminal shell."

}

function rvm-version {

  info "rvm $rvm_version"

}

function rvm {

  while [ $# -gt 0 ] ; do
    arg="$1" ; shift
    case "$arg" in 
      install|use|path|info|gemdir|gemdup|setup|version)
                       action=$arg                ;;
      ruby|jruby|ree|leopard|default)
                       implementation="$arg"      ;;
      -v|--version)    version="$1"      ; shift  ;;
      -l|--level)      patchlevel="$1"   ; shift  ;;
      -p|--prefix)     install_path="$1" ; shift  ;;  
      -m|--manager)    manager="$1"      ; shift  ;;
      -d|--debug)      debug=true                 ;;
      *)               usage
    esac 
  done 
  
  curl="curl -O -L -s "
  implementation=${implementation-'ruby'}
  username=`whoami`
  if [ "$username" = "root" ] ; then 
    prefix_path=${prefix-/usr/local/}
  else
    prefix_path=${prefix-$HOME/.}
  fi

  # TODO: Sanitize user input, ensure that there is a / a the end...
  source_path="${prefix_path}rvm/src"
  install_path="${prefix_path}rvm"
  
  mkdir -p $source_path $install_path

  original_path=`cat $install_path/.original_path`
  if [ -z "$original_path" ] ; then 
    echo $PATH > $install_path/.original_path
    original_path=$PATH
  fi

  case "$action" in
    install) 
      if [ "$implementation" = "all" ] ; then 
        for implementation in ruby jruby ree ; do
          if [ "$implementation" = "ruby" ] ; then
            for versions in 1.8.6 1.8.7 1.9.1 ; do
              ruby-install 
            done
          else
              ruby-install 
          fi
        done
      else
        ruby-install $implementation $version $patchlevel 
      fi
    ;;
    use)     ruby-use     $implementation $version $patchlevel ;;
    gemdir)  ruby-gem-dir $implementation $version $patchlevel ;;
    gemdup)  ruby-gem-dup $implementation $version $patchlevel ;;
    path)    ruby-path    $implementation $version $patchlevel ;;
    info)    ruby-info    $implementation $version $patchlevel ;;
    version) rvm-version                                       ;;
    setup)   rvm-setup                                         ;;
    *) usage ; fail  "unknown action '$action'"
  esac

}