#!/usr/bin/env ruby
#  Phusion Passenger - https://www.phusionpassenger.com/
#  Copyright (c) 2010-2015 Phusion Holding B.V.
#
#  "Passenger", "Phusion Passenger" and "Union Station" are registered
#  trademarks of Phusion Holding B.V.
#
#  Permission is hereby granted, free of charge, to any person obtaining a copy
#  of this software and associated documentation files (the "Software"), to deal
#  in the Software without restriction, including without limitation the rights
#  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
#  copies of the Software, and to permit persons to whom the Software is
#  furnished to do so, subject to the following conditions:
#
#  The above copyright notice and this permission notice shall be included in
#  all copies or substantial portions of the Software.
#
#  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
#  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
#  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
#  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
#  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
#  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
#  THE SOFTWARE.

## Magic comment: begin bootstrap ##
require 'phusion_passenger'
## Magic comment: end bootstrap ##

PhusionPassenger.locate_directories

require 'digest/sha2'
require 'optparse'
require 'fileutils'
PhusionPassenger.require_passenger_lib 'platform_info/ruby'
PhusionPassenger.require_passenger_lib 'platform_info/openssl'
PhusionPassenger.require_passenger_lib 'abstract_installer'
PhusionPassenger.require_passenger_lib 'utils/terminal_choice_menu'
PhusionPassenger.require_passenger_lib 'utils/tmpio'
PhusionPassenger.require_passenger_lib 'utils/shellwords'

DOWNLOAD_OPTION = {
  :connect_timeout => 30,
  :idle_timeout    => 30
}

class Installer < PhusionPassenger::AbstractInstaller
  include PhusionPassenger
  TerminalChoiceMenu = PhusionPassenger::Utils::TerminalChoiceMenu

  def dependencies
    specs = [
      'depcheck_specs/compiler_toolchain',
      'depcheck_specs/ruby',
      'depcheck_specs/gems',
      'depcheck_specs/libs',
      'depcheck_specs/utilities'
    ]
    ids = [
      'cc',
      'c++',
      'download-tool',
      'libcurl-dev',
      'openssl-dev',
      'zlib-dev',
      'rake',
      'ruby-openssl',
      'rubygems'
    ]
    if @languages.include?("ruby")
      if PlatformInfo.passenger_needs_ruby_dev_header?
        ids << 'ruby-dev'
      end
      ids << 'rack'
    end
    return [specs, ids]
  end

  def install_doc_url
    "https://www.phusionpassenger.com/library/install/nginx/"
  end

  def troubleshooting_doc_url
    "https://www.phusionpassenger.com/library/admin/nginx/troubleshooting/"
  end

  def run_steps
    # Make sure the configure script finds the correct
    # passenger-config command.
    ENV['PATH'] = PhusionPassenger.bin_dir + ":" + ENV['PATH']

    show_welcome_screen
    query_interested_languages
    check_gem_install_permission_problems || exit(1)
    check_directory_accessible_by_web_server
    check_nginx_module_sources_available || exit(1)
    check_dependencies || exit(1)
    if needs_compiling_support_files?
      check_whether_we_can_write_to(PhusionPassenger.build_system_dir) || exit(1)
    end
    check_whether_os_is_broken
    check_whether_system_has_enough_ram

    download_and_install = should_we_download_and_install_nginx_automatically?
    if pcre_is_installed?
      @pcre_source_dir = nil
    else
      @pcre_source_dir = download_and_extract_pcre
    end
    if download_and_install
      nginx_source_dir = download_and_extract_nginx
      if nginx_source_dir.nil?
        show_possible_solutions_for_download_and_extraction_problems
        exit(1)
      end
      nginx_prefix = ask_for_nginx_install_prefix
      check_whether_other_nginx_installations_exist(nginx_prefix)
      if @extra_configure_flags == "none"
        extra_nginx_configure_flags = nil
      else
        extra_nginx_configure_flags = @extra_configure_flags
      end
    else
      nginx_source_dir = ask_for_nginx_source_dir
      nginx_prefix = ask_for_nginx_install_prefix
      check_whether_other_nginx_installations_exist(nginx_prefix)
      extra_nginx_configure_flags = ask_for_extra_nginx_configure_flags(nginx_prefix)
    end
    check_whether_we_can_write_to(nginx_prefix) || exit(1)
    nginx_config_already_exists_before_installing = nginx_config_exists?(nginx_prefix)
    if needs_compiling_support_files?
      if !compile_passenger_support_files
        show_possible_solutions_for_compilation_and_installation_problems
        exit(1)
      end
    end
    if install_nginx(nginx_source_dir, nginx_prefix, extra_nginx_configure_flags)
      if nginx_config_already_exists_before_installing || !locate_nginx_config_file(nginx_prefix)
        show_passenger_config_snippets(nginx_prefix)
      else
        insert_passenger_config_snippets(nginx_prefix)
      end
      show_deployment_example
    else
      show_possible_solutions_for_compilation_and_installation_problems
      exit(1)
    end
  end

  def before_install
    super
    myself = `whoami`.strip
    @working_dir = PhusionPassenger::Utils.mktmpdir("passenger.", PlatformInfo.tmpexedir)
  end

  def after_install
    super
    FileUtils.remove_entry_secure(@working_dir) if @working_dir
  end

private
  def show_welcome_screen
    render_template 'nginx/welcome', :version => VERSION_STRING
    wait
  end

  def query_interested_languages
    menu = TerminalChoiceMenu.new(["Ruby", "Python", "Node.js", "Meteor"])
    menu["Ruby"].checked = interesting_language?('ruby')
    menu["Python"].checked = interesting_language?('python')
    menu["Node.js"].checked = interesting_language?('nodejs', 'node')
    menu["Meteor"].checked = interesting_language?('meteor')

    new_screen
    puts "<banner>Which languages are you interested in?</banner>"
    puts
    if interactive?
      puts "Use <space> to select."
      puts "<dgray>If the menu doesn't display correctly, press '!'</dgray>"
    else
      puts "Override selection with --languages."
    end
    puts

    if interactive?
      begin
        menu.query
      rescue Interrupt
        raise Abort
      end
    else
      menu.display_choices
      puts
    end

    @languages = menu.selected_choices.map{ |x| x.downcase.gsub(/\./, '') }
  end

  def interesting_language?(name, command = nil)
    if @languages
      return @languages.include?(name)
    else
      return !!PlatformInfo.find_command(command || name)
    end
  end

  def check_nginx_module_sources_available
    if PhusionPassenger.custom_packaged? &&
       (!PhusionPassenger.nginx_module_source_dir || !File.exist?(PhusionPassenger.nginx_module_source_dir))
      new_screen
      render_template 'nginx/nginx_module_sources_not_available'
      return false
    else
      return true
    end
  end

  def needs_compiling_support_files?
    return !PhusionPassenger.build_system_dir.nil?
  end

  def compile_passenger_support_files
    new_screen
    puts "<banner>Compiling Passenger support files...</banner>"
    Dir.chdir(PhusionPassenger.build_system_dir) do
      return sh("env NOEXEC_DISABLE=1 #{PlatformInfo.rake_command} nginx:clean nginx RELEASE=yes")
    end
  end

  def should_we_download_and_install_nginx_automatically?
    new_screen
    render_template 'nginx/query_download_and_install',
      :nginx_version => PREFERRED_NGINX_VERSION
    puts

    if @auto_download
      puts "<b>=> Proceeding with choice 1.</b>"
      return true
    elsif @nginx_source_dir
      puts "<b>=> Proceeding with choice 2.</b>"
      return false
    elsif @auto
      puts "<b>=> Proceeding with choice 1.</b>"
      return true
    else
      choice = prompt("Enter your choice (1 or 2) or press Ctrl-C to abort") do |input|
        if input == "1" || input == "2"
          true
        elsif input.empty?
          puts "<red>No choice has been given.</red>"
          false
        else
          puts "<red>'#{input}' is not a valid choice.</red>"
          false
        end
      end
      return choice == "1"
    end
  end

  def download_and_extract_pcre
    new_screen
    puts "<banner>PCRE (required by Nginx) not installed, downloading it...</banner>"

    url = "http://downloads.sourceforge.net/project/pcre/pcre/#{PREFERRED_PCRE_VERSION}/pcre-#{PREFERRED_PCRE_VERSION}.tar.gz"
    dirname = "pcre-#{PREFERRED_PCRE_VERSION}"
    tarball = "#{@working_dir}/pcre.tar.gz"

    if download(url, tarball, DOWNLOAD_OPTION)
      Dir.chdir(@working_dir) do
        puts "<banner>Verifying PCRE checksum...</banner>"
        if sha256_file(tarball) != PCRE_SHA256_CHECKSUM
          new_screen
          render_template "nginx/pcre_checksum_could_not_be_verified"
          wait
          return nil
        end

        puts "<banner>Extracting PCRE source tarball...</banner>"
        if sh("tar", "xzvf", tarball)
          return "#{@working_dir}/#{dirname}"
        else
          new_screen
          render_template "nginx/pcre_could_not_be_extracted"
          wait
          return nil
        end
      end
    else
      new_screen
      render_template "nginx/pcre_could_not_be_downloaded"
      wait
      return nil
    end
  rescue Interrupt
    exit 2
  end

  def download_and_extract_nginx
    new_screen
    puts "<banner>Downloading Nginx...</banner>"

    url = "http://www.nginx.org/download/nginx-#{PREFERRED_NGINX_VERSION}.tar.gz"
    dirname = "nginx-#{PREFERRED_NGINX_VERSION}"
    tarball = "#{@working_dir}/nginx.tar.gz"

    if download(url, tarball, DOWNLOAD_OPTION)
      Dir.chdir(@working_dir) do
        puts "<banner>Verifying Nginx checksum...</banner>"
        if sha256_file(tarball) != NGINX_SHA256_CHECKSUM
          return nil
        end

        puts "<banner>Extracting Nginx source tarball...</banner>"
        if sh("tar", "xzvf", tarball)
          return "#{@working_dir}/#{dirname}"
        else
          return nil
        end
      end
    else
      return nil
    end
  rescue Interrupt
    exit 2
  end

  def show_possible_solutions_for_download_and_extraction_problems
    new_screen
    render_template "nginx/possible_solutions_for_download_and_extraction_problems"
    puts
  end

  def ask_for_nginx_install_prefix
    new_screen
    puts "<banner>Where do you want to install Nginx to?</banner>"
    puts
    if @prefix
      puts "<b>=> #{@prefix}</b>"
      return @prefix
    elsif @auto
      puts "<b>=> /opt/nginx</b>"
      return "/opt/nginx"
    else
      prefix = prompt("Please specify a prefix directory [/opt/nginx]") do |input|
        if input.empty? || input =~ %r(/)
          true
        else
          puts "<red>Please specify an absolute path.</red>"
          false
        end
      end
      if prefix.empty?
        prefix = "/opt/nginx"
      end
      return prefix
    end
  end

  def check_whether_other_nginx_installations_exist(nginx_prefix)
    check_for = [
      "/usr/bin/nginx",
      "/usr/sbin/nginx"
    ]
    existing_binary = nil
    check_for.each do |filename|
      if File.exist?(filename)
        existing_binary = filename
        break
      end
    end
    if existing_binary
      new_screen
      render_template 'nginx/other_nginx_installations_exist',
        :existing_binary => existing_binary,
        :prefix => nginx_prefix
      wait
    end
  end

  def ask_for_nginx_source_dir
    new_screen
    puts "<banner>Where is your Nginx source code located?</banner>"
    puts
    if @nginx_source_dir
      puts "<b>=> #{@nginx_source_dir}</b>"
      return @nginx_source_dir
    else
      return prompt("Please specify the directory") do |input|
        if input =~ %r(/)
          if File.exist?("#{input}/src/core/nginx.c")
            true
          else
            puts "<red>'#{input}' does not look like an Nginx source directory.</red>"
            false
          end
        else
          puts "<red>Please specify an absolute path.</red>"
          false
        end
      end
    end
  end

  def ask_for_extra_nginx_configure_flags(prefix)
    done = false
    while !done
      new_screen
      render_template 'nginx/ask_for_extra_configure_flags',
        :command => build_nginx_configure_command(prefix)
      puts
      if @extra_configure_flags
        if @extra_configure_flags == "none"
          extra_args = ""
          puts "<b>=> No extra configure flags.</b>"
        else
          extra_args = @extra_configure_flags
          puts "<b>=> #{extra_args}</b>"
        end
        return extra_args
      elsif @auto
        puts "<b>=> No extra configure flags.</b>"
        return ""
      else
        extra_args = prompt "Extra arguments to pass to configure script"

        new_screen
        render_template 'nginx/confirm_extra_configure_flags',
          :command => build_nginx_configure_command(prefix, extra_args)
        puts
        answer = prompt("Is this what you want? (yes/no) [default=yes]") do |input|
          if input.empty? || input == "yes" || input == "no"
            true
          else
            puts "<red>Please enter 'yes' or 'no'.</red>"
            false
          end
        end
        done = answer.empty? || answer == "yes"
      end
    end
    return extra_args
  end

  def check_whether_we_can_write_to(dir)
    FileUtils.mkdir_p(dir)
    File.new("#{dir}/__test__.txt", "w").close
    return true
  rescue
    new_screen
    if Process.uid == 0
      render_template 'nginx/cannot_write_to_dir', :dir => dir
    else
      render_template 'installer_common/run_installer_as_root',
        :dir  => dir,
        :sudo => PhusionPassenger::PlatformInfo.ruby_sudo_command,
        :sudo_s_e => PhusionPassenger::PlatformInfo.ruby_sudo_shell_command("-E"),
        :ruby => PhusionPassenger::PlatformInfo.ruby_command,
        :installer => "#{PhusionPassenger.bin_dir}/passenger-install-nginx-module #{ORIG_ARGV.join(' ')}"
    end
    return false
  ensure
    File.unlink("#{dir}/__test__.txt") rescue nil
  end

  def nginx_config_exists?(prefix)
    return !!locate_nginx_config_file(prefix)
  end

  def install_nginx(source_dir, prefix, extra_configure_flags)
    Dir.chdir(source_dir) do
      new_screen
      puts "<banner>Compiling and installing Nginx...</banner>"
      if !sh(build_nginx_configure_command(prefix, extra_configure_flags)) ||
         !sh("make") ||
         !sh("make install")
        return false
      end
    end
    return true
  rescue Interrupt
    raise Aborted
  end

  def show_passenger_config_snippets(prefix)
    new_screen
    render_template 'nginx/config_snippets',
      :config_file => locate_nginx_config_file(prefix),
      :passenger_root => PhusionPassenger.install_spec,
      :ruby => PlatformInfo.ruby_command
    wait
  end

  def show_deployment_example
    line
    puts
    render_template 'nginx/deployment_example',
      :deployment_guide_url => "https://www.phusionpassenger.com/library/deploy/nginx/deploy/",
      :phusion_website => PHUSION_WEBSITE,
      :passenger_website => PASSENGER_WEBSITE
  end

  def show_possible_solutions_for_compilation_and_installation_problems
    line
    puts
    render_template 'nginx/possible_solutions_for_compilation_and_installation_problems',
      :support_url => SUPPORT_URL
  end

  def locate_nginx_config_file(prefix)
    ["#{prefix}/conf/nginx.conf", "#{prefix}/etc/nginx.conf"].each do |filename|
      if File.exist?(filename)
        return filename
      end
    end
    return nil
  end

  def insert_passenger_config_snippets(prefix)
    config_file = locate_nginx_config_file(prefix)
    contents = File.read(config_file)
    contents.sub!(/^http \{/,
      "http {\n" <<
      "    passenger_root #{PhusionPassenger.install_spec};\n" <<
      "    passenger_ruby #{PlatformInfo.ruby_command};\n")
    File.open(config_file, 'w') do |f|
      f.write(contents)
    end

    new_screen
    render_template 'nginx/config_snippets_inserted',
      :config_file => config_file,
      :passenger_root => PhusionPassenger.install_spec,
      :ruby => PlatformInfo.ruby_command
    wait
  end

  def build_nginx_configure_command(prefix, extra_configure_flags = nil)
    extra_cflags = "-Wno-error #{PlatformInfo.openssl_extra_cflags}".strip
    extra_ldflags = PlatformInfo.openssl_extra_ldflags

    command = "sh ./configure --prefix='#{prefix}' "
    command << "--with-http_ssl_module "
    command << "--with-http_gzip_static_module "
    command << "--with-http_stub_status_module "
    command << "--with-cc-opt=#{Shellwords.escape extra_cflags} "
    command << "--with-ld-opt=#{Shellwords.escape extra_ldflags} "
    if @pcre_source_dir
      command << "--with-pcre='#{@pcre_source_dir}' "
    elsif !pcre_is_installed?
      command << "--without-http_rewrite_module "
    end
    command << "--add-module='#{PhusionPassenger.nginx_module_source_dir}' #{extra_configure_flags}"
    command.strip!
    return command
  end

  def pcre_is_installed?
    if @pcre_is_installed.nil?
      @pcre_is_installed = begin
        File.open('/tmp/passenger-check.c', 'w') do |f|
          f.puts("#include <pcre.h>")
        end
        Dir.chdir('/tmp') do
          # Nginx checks for PCRE in multiple places...
          system("(gcc -I/usr/local/include -I/usr/include/pcre " <<
            "-I/usr/pkg/include -I/opt/local/include " <<
            "-c passenger-check.c) >/dev/null 2>/dev/null")
        end
      ensure
        File.unlink('/tmp/passenger-check.c') rescue nil
        File.unlink('/tmp/passenger-check.o') rescue nil
      end
    end
    return @pcre_is_installed
  end

  def sha256_file(path)
    # We do this instead of using #file, for Ruby 1.8.5 support.
    digest = Digest::SHA256.new
    File.open(path, "rb") do |f|
      buf = ''
      buf.force_encoding('binary') if buf.respond_to?(:force_encoding)
      while !f.eof?
        f.read(1024 * 16, buf)
        digest.update(buf)
      end
    end
    return digest.hexdigest
  end
end

ORIG_ARGV = ARGV.dup
options = {}
parser = OptionParser.new do |opts|
  opts.banner = "Usage: passenger-install-nginx-module [options]"
  opts.separator ""

  indent = ' ' * 37
  opts.separator "Options:"
  opts.on("--auto", "Automatically confirm 'Press ENTER to\n" <<
          "#{indent}continue' prompts.") do
    options[:auto] = true
  end
  opts.on("--prefix=DIR", String, "Use the given Nginx install prefix instead\n" <<
          "#{indent}of asking for it interactively.") do |dir|
    options[:prefix] = dir
  end
  opts.on("--auto-download", "Download and install Nginx automatically,\n" <<
          "#{indent}instead of asking interactively whether to\n" <<
          "#{indent}download+install or to use an existing\n" <<
          "#{indent}Nginx source directory.") do
    options[:auto_download] = true
  end
  opts.on("--nginx-source-dir=DIR", String, "Compile and install Nginx using the given\n" <<
          "#{indent}Nginx source directory, instead of\n" <<
          "#{indent}interactively asking to download+install\n" <<
          "#{indent}or to use an existing Nginx source\n" <<
          "#{indent}directory. Conflicts with --auto-download.") do |dir|
    options[:nginx_source_dir] = dir
  end
  opts.on("--extra-configure-flags=STRING", String, "Pass these extra flags to Nginx's\n" <<
          "#{indent}'configure' script, instead of asking for\n" <<
          "#{indent}it interactively. Specify 'none' if you\n" <<
          "#{indent}do not want to pass additional flags but do\n" <<
          "#{indent}not want this installer to ask\n" <<
          "#{indent}interactively either.") do |flags|
    options[:extra_configure_flags] = flags
  end
  opts.on("--languages NAMES", "Comma-separated list of interested\n" <<
      "#{indent}languages (e.g.\n" <<
      "#{indent}'ruby,python,nodejs,meteor')") do |value|
    options[:languages] = value.split(",")
  end
  opts.on("--force-colors", "Display colors even if stdout is not a TTY") do
    options[:colorize] = true
  end
end
begin
  parser.parse!
rescue OptionParser::ParseError => e
  puts e
  puts
  puts "Please see '--help' for valid options."
  exit 1
end

if options[:auto_download] && options[:nginx_source_dir]
  STDERR.puts "You cannot specify both --auto-download and --nginx-source-dir."
  exit 1
end

Installer.new(options).run