#!/usr/bin/env ruby

require 'pp'

$nokogiri='nokogiri'

DEFAULT=%w{sunstone quota cloud ozones_server auth_ldap}

if defined?(RUBY_VERSION) && RUBY_VERSION>="1.8.7"
    SQLITE='sqlite3'
else
    SQLITE='sqlite3-ruby --version 1.2.0'
end

GROUPS={
    :quota => [SQLITE, 'sequel'],
    :sunstone => ['json', 'rack', 'sinatra', 'thin', 'sequel', SQLITE],
    :cloud => %w{amazon-ec2 rack sinatra thin uuidtools curb json},
    :ozones_client => %w{json},
    :ozones_server => %w{json sequel}+[
        SQLITE, 'mysql'
    ],
    :ozones_server_sqlite => %w{json sequel}<<SQLITE,
    :ozones_server_mysql => %w{json sequel mysql},
    :auth_ldap => 'net-ldap'
}

PACKAGES=GROUPS.keys

GEM_TEST={
    'net-ldap' => 'net/ldap'
}

DISTRIBUTIONS={
    :debian => {
        :id => ['Ubuntu', 'Debian'],
        :dependencies => {
            SQLITE      => ['gcc', 'libsqlite3-dev'],
            'mysql'     => ['gcc', 'libmysqlclient-dev'],
            'curb'      => ['gcc', 'libcurl4-openssl-dev'],
            'nokogiri'  => %w{gcc rake libxml2-dev libxslt1-dev},
            'xmlparser' => ['gcc', 'libexpat1-dev'],
            'thin'      => ['g++'],
            'json'      => ['make', 'gcc']
        },
        :install_command => 'apt-get install',
        :gem_env    => {
            'rake'      => '/usr/bin/rake'
        }
    },
    :redhat => {
        :id => ['CentOS', /^RedHat/],
        :dependencies => {
            SQLITE      => ['gcc', 'sqlite-devel'],
            'mysql'     => ['gcc', 'mysql-devel'],
            'curb'      => ['gcc', 'curl-devel'],
            'nokogiri'  => %w{gcc rubygem-rake libxml2-devel libxslt-devel},
            'xmlparser' => ['gcc', 'expat-devel'],
            'thin'      => ['gcc-c++'],
            'json'      => ['make', 'gcc']
        },
        :install_command => 'yum install'
    },
    :suse => {
        :id => [/^SUSE/],
        :dependencies => {
            SQLITE      => ['gcc', 'sqlite3-devel'],
            'mysql'     => ['gcc', 'libmysqlclient-devel'],
            'curb'      => ['gcc', 'libcurl-devel'],
            'nokogiri'  => %w{rubygem-rake gcc rubygem-rake libxml2-devel libxslt-devel},
            'xmlparser' => ['gcc', 'libexpat-devel'],
            'thin'      => ['rubygem-rake', 'gcc-c++'],
            'json'      => ['make', 'gcc']
        },
        :install_command => 'zypper install'
    }
}


class String
    def unindent(spaces=4)
        self.gsub!(/^ {#{spaces}}/, '')
    end
end

def good_gem_version?
    v=`gem --version`.strip
    version=Gem::Version.new(v)
    version>=Gem::Version.new('1.3.6')
end

def select_distribution
    items=[]
    counter=0

    puts(<<-EOT.unindent(8))
        Select your distribution or press enter to continue without
        installing dependencies.

EOT

    DISTRIBUTIONS.each do |name, dist|
        names=dist[:id].map do |r|
            if Regexp===r
                r.source.gsub(/[^\w\d]/, '')
            else
                r
            end
        end.join('/')
        text="#{items.length}. #{names}"

        items << name

        puts text
    end

    puts

    options=(0..items.length).to_a.map {|k| k.to_s }

    option=STDIN.readline[0,1]

    if options.include?(option)
        item=items[option.to_i]
        [item, DISTRIBUTIONS[items[option.to_i]]]
    else
        nil
    end
end

def install_rubygems
    if !good_gem_version?
        puts(<<-EOT.unindent())
            The rubygems version installed is too old to install some required
            libraries. We are about to update your rubygems version. If you
            want to do this by other means cancel this installation with
            CTRL+C now.

            Press ENTER to continue...

EOT

        STDIN.readline

        `gem install rubygems-update --version '= 1.3.6'`

        if $?.exitstatus!=0
            puts "Error updating rubygems"
            exit(-1)
        end

        update_rubygems_path=[
            '/usr/bin/update_rubygems',
            '/var/lib/gems/1.8/bin/update_rubygems',
            '/var/lib/gems/1.9/bin/update_rubygems'
        ]

        installed=false

        update_rubygems_path.each do |path|
            if File.exist?(path)
                `#{path}`

                if $?.exitstatus!=0
                    puts "Error executing update_rubygems"
                    exit(-1)
                end

                installed=true
                break
             end
        end

        if !installed
            puts "Could not find update_rubygems executable"
            exit(-1)
        end
    end
end

def installed_gems
    text=`gem list --no-versions --no-details`
    if $?.exitstatus!=0
        nil
    else
        text.split(/\s+/)
    end
end

def try_library(name, error_message)
    if GEM_TEST[name.to_s]
        lib_test=GEM_TEST[name.to_s]
    else
        lib_test=name.to_s
    end

    begin
        require lib_test
    rescue LoadError, Exception
        STDERR.puts error_message
        exit(-1)
    end
end

def install_warning(packages)
#    puts "Use -h for help"
#    puts
    puts "About to install the gems for these components:"
    puts "* "<<packages.join("\n* ")
    puts
    puts "Press enter to continue..."
    yes=STDIN.readline
end

def help
    puts "Specify the package dependencies from this list:"
    puts "* "<<PACKAGES.join("\n* ")
    puts
    puts "If no parameters are specified then this list will be used:"
    puts DEFAULT.join(' ')
    puts
    puts "Use --check parameter to search for non installed libraries."
    puts "Use --no-nokogiri parameter if you don't want to install"
    puts "nokogiri gem."
end

def get_gems(packages)
    (packages.map do |package|
        GROUPS[package.to_sym]
    end+[$nokogiri]).flatten.uniq-installed_gems
end

def detect_distro
    begin
        lsb_info=`lsb_release -a`
    rescue
    end

    if $?.exitstatus!=0
        STDERR.puts(<<-EOT.unindent(12))
            lsb_release command not found. If you are using a RedHat based
            distribution install redhat-lsb

EOT
        return nil
    end

    distribution_id=nil

    lsb_info.scan(/^Distributor ID:\s*(.*?)$/) do |m|
        distribution_id=m.first.strip
    end

    return nil if !distribution_id

    distro=nil

    DISTRIBUTIONS.find do |dist, info|
        info[:id].find do |dist_id|
            dist_id===distribution_id
        end
    end
end

def get_dependencies(gems, dependencies)
    deps=[]

    gems.each do |gem_name|
        deps<<dependencies[gem_name]
    end

    deps.flatten!
    deps.compact!
    deps.uniq!

    deps
end

def install_dependencies(gems, distro)
    if !distro
        puts(<<-EOT.unindent(12))
            Distribution not detected. Make sure you manually install the
            dependencies described in Building from Source from the OpenNebula
            documentation.

            Press enter to continue...
        EOT
        STDIN.readline
    else
        puts "Distribution \"#{distro.first}\" detected."
        deps=get_dependencies(gems, distro.last[:dependencies])

        if deps.length==0
            return
        end

        puts "About to install these dependencies:"
        puts "* "<<deps.join("\n* ")
        puts
        puts "Press enter to continue..."
        STDIN.readline

        command=distro.last[:install_command]+" "<<deps.join(' ')
        puts command
        system command
    end
end

def run_command(cmd)
    puts cmd
    system cmd
    #system "true"

    if $?!=0
        puts "Error executing #{cmd}"
        exit(-1)
    end
end

def install_gems(packages)
    gems_list=get_gems(packages)

    if gems_list.empty?
        puts "Gems already installed"
        exit(0)
    end

    dist=detect_distro
    if !dist
        dist=select_distribution
    end

    install_dependencies(gems_list, dist)

    packages_string=gems_list.join(' ')

    prefix=""

    if dist && dist.last[:gem_env]
        prefix=dist.last[:gem_env].collect do |name, value|
            "#{name}=\"#{value}\""
        end.join(' ')+' '
    end

    command_string = "#{prefix}gem install --no-ri --no-rdoc"

    install_warning(packages)

    simple_gems=gems_list.select {|g| !(g.match(/\s/)) }
    if simple_gems and !simple_gems.empty?
        cmd=command_string+" " << simple_gems.join(' ')
        run_command(cmd)
    end

    special_gems=gems_list.select {|g| g.match(/\s/) }
    special_gems.each do |gem|
        cmd=command_string+" "<<gem
        run_command(cmd)
    end
end

def check_lib(lib)
    begin
        require lib
        true
    rescue LoadError, Exception
        false
    end
end

def check_gems(packages)
    list=get_gems(packages).compact
    gems=list.map {|g| g.strip.split(/\s+/).first }

    not_installed=Array.new

    gems.each do |lib_name|
        if !check_lib(lib_name)
            not_installed << lib_name
        end
    end

    if not_installed.empty?
        puts "All ruby libraries installed"
        exit(0)
    else
        puts "These ruby libraries are not installed:"
        puts ""
        puts "* "+not_installed.join("\n* ")
        exit(-1)
    end
end

try_library :rubygems, <<-EOT.unindent
    rubygems required to use this tool

    Use one of these methods:

        * Debian/Ubuntu
            apt-get install rubygems libopenssl-ruby

        * RHEL/CENTOS
            yum install rubygems

        * SUSE
            zypper install rubygems

        * Specific rubygems package for your distro

        * Follow the instructions from http://rubygems.org/pages/download
EOT

try_library :mkmf, <<-EOT.unindent
    ruby development package is needed to install gems

    Use one of these methods:

        * Debian/Ubuntu
            apt-get install ruby-dev

        * RHEL/CENTOS
            yum install ruby-devel

        * Install the ruby development package for your distro
EOT

try_library :openssl, <<-EOT.unindent
    ruby openssl libraries are needed. They usually come as companion
    package to ruby.
EOT

install_rubygems

command=''
params=ARGV

if params.include?('--no-nokogiri')
    params-=['--no-nokogiri']
    $nokogiri=nil
end

if params.include?('-h')
    params-=['-h']
    command='help'
elsif params.include?('--check')
    params-=['--check']
    command='check'
else
    command='install'
end

if params.length>0
    packages=params
else
    packages=DEFAULT
end


case command
when 'help'
    help
    exit(0)
when 'check'
    check_gems(packages)
when 'install'
    install_gems(packages)
end




