#!/usr/bin/env ruby
#  Phusion Passenger - http://www.modrails.com/
#  Copyright (c) 2009 Phusion
#
#  "Phusion Passenger" is a trademark of Hongli Lai & Ninh Bui.
#
#  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.

PASSENGER_ROOT = File.expand_path(File.dirname(__FILE__) << "/..")
$LOAD_PATH.unshift("#{PASSENGER_ROOT}/lib")
$LOAD_PATH.unshift("#{PASSENGER_ROOT}/ext")

require 'optparse'
require 'fileutils'
require 'phusion_passenger/platform_info'
require 'phusion_passenger/dependencies'
require 'phusion_passenger/abstract_installer'
include PlatformInfo

class Installer < PhusionPassenger::AbstractInstaller
	include PhusionPassenger
	
	NGINX_VERSION = "0.6.37"
	
	def dependencies
		result = [
			Dependencies::GCC,
			Dependencies::Ruby_DevHeaders,
			Dependencies::Ruby_OpenSSL,
			Dependencies::RubyGems,
			Dependencies::Rake,
			Dependencies::Zlib_Dev
		]
		if Dependencies.fastthread_required?
			result << Dependencies::FastThread
		end
		return result
	end
	
	def users_guide
		return "#{DOCDIR}/Users guide Nginx.html"
	end
	
	def install!
		Dir.chdir(PASSENGER_ROOT)
		show_welcome_screen
		check_dependencies || exit(1)
		
		check_whether_we_can_write_to(PASSENGER_ROOT) || exit(1)
		
		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
			extra_nginx_configure_flags = nil
		else
			nginx_source_dir = ask_for_nginx_source_dir
			nginx_prefix = ask_for_nginx_install_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)
		compile_passenger_support_files || exit(1)
		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

private
	def show_welcome_screen
		render_template 'nginx/welcome', :version => VERSION_STRING
		wait
	end
	
	def compile_passenger_support_files
		new_screen
		color_puts "<banner>Compiling Passenger support files...</banner>"
		return sh(RUBY, "-S", PlatformInfo.rake, "clean", "nginx")
	end
	
	def should_we_download_and_install_nginx_automatically?
		new_screen
		render_template 'nginx/query_download_and_install',
			:nginx_version => NGINX_VERSION
		puts
		
		if @auto_download
			color_puts "<b>=> Proceeding with choice 1.</b>"
			return true
		elsif @nginx_source_dir
			color_puts "<b>=> Proceeding with choice 2.</b>"
			return false
		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?
					color_puts "<red>No choice has been given.</red>"
					false
				else
					color_puts "<red>'#{input}' is not a valid choice.</red>"
					false
				end
			end
			return choice == "1"
		end
	end
	
	def download_and_extract_pcre
		new_screen
		color_puts "<banner>PCRE (required by Nginx) not installed, downloading it...</banner>"
		
		basename = "pcre-7.8.tar.gz"
		dirname = "pcre-7.8"
		url = "ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/#{basename}"
		File.unlink("/tmp/#{basename}") rescue nil
		FileUtils.rm_rf("/tmp/#{dirname}")
		
		if download(url, "/tmp/#{basename}")
			Dir.chdir("/tmp") do
				color_puts "<banner>Extracting PCRE source tarball...</banner>"
				if sh("tar", "xzvf", basename)
					return "/tmp/#{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
		color_puts "<banner>Downloading Nginx...</banner>"
		
		basename = "nginx-#{NGINX_VERSION}.tar.gz"
		url = "http://sysoev.ru/nginx/#{basename}"
		File.unlink("/tmp/#{basename}") rescue nil
		FileUtils.rm_rf("/tmp/nginx-#{NGINX_VERSION}")
		
		if download(url, "/tmp/#{basename}")
			Dir.chdir("/tmp") do
				color_puts "<banner>Extracting Nginx source tarball...</banner>"
				if sh("tar", "xzvf", basename)
					return "/tmp/nginx-#{NGINX_VERSION}"
				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
		color_puts "<banner>Where do you want to install Nginx to?</banner>"
		puts
		if @prefix
			color_puts "<b>=> #{@prefix}</b>"
			return @prefix
		else
			prefix = prompt("Please specify a prefix directory [/opt/nginx]") do |input|
				if input.empty? || input =~ %r(/)
					true
				else
					color_puts "<red>Please specify an absolute path.</red>"
					false
				end
			end
			if prefix.empty?
				prefix = "/opt/nginx"
			end
			return prefix
		end
	end
	
	def ask_for_nginx_source_dir
		new_screen
		color_puts "<banner>Where is your Nginx source code located?</banner>"
		puts
		if @nginx_source_dir
			color_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
						color_puts "<red>'#{input}' does not look like an Nginx source directory.</red>"
						false
					end
				else
					color_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 = ""
					color_puts "<b>=> No extra configure flags.</b>"
				else
					extra_args = @extra_configure_flags
					color_puts "<b>=> #{extra_args}</b>"
				end
				return extra_args
			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
						color_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 'nginx/run_installer_as_root', :dir => dir
		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
			color_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
	end
	
	def show_passenger_config_snippets(prefix)
		new_screen
		render_template 'nginx/config_snippets',
			:config_file => locate_nginx_config_file(prefix),
			:passenger_root => PASSENGER_ROOT,
			:ruby => RUBY
		wait
	end
	
	def show_deployment_example
		line
		puts
		render_template 'nginx/deployment_example',
			:users_guide => users_guide,
			: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',
			:users_guide => users_guide,
			:passenger_website => PASSENGER_WEBSITE
	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 #{PASSENGER_ROOT};\n" <<
			"    passenger_ruby #{RUBY};\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 => PASSENGER_ROOT,
			:ruby => RUBY
		wait
	end
	
	def build_nginx_configure_command(prefix, extra_configure_flags = nil)
		command = "./configure --prefix='#{prefix}' "
		if @pcre_source_dir
			command << "--with-pcre='#{@pcre_source_dir}' "
		elsif !pcre_is_installed?
			command << "--without-http_rewrite_module "
		end
		command << "--add-module='#{PASSENGER_ROOT}/ext/nginx' #{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
					system("(gcc -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 download(url, output)
		if PlatformInfo.find_command("wget")
			return sh("wget", "-O", output, url)
		else
			return sh("curl", url, "-o", output)
		end
	end
end

options = {}
parser = OptionParser.new do |opts|
	opts.banner = "Usage: passenger-install-nginx-module [options]"
	opts.separator ""
	
	opts.separator "Options:"
	opts.on("--auto", "Automatically confirm 'Press ENTER to\n" <<
	        "#{' ' * 37}continue' prompts.") do
		options[:auto] = true
	end
	opts.on("--prefix=DIR", String, "Use the given Nginx install prefix instead\n" <<
	        "#{' ' * 37}of asking for it interactively.") do |dir|
		options[:prefix] = dir
	end
	opts.on("--auto-download", "Download and install Nginx automatically,\n" <<
	        "#{' ' * 37}instead of asking interactively whether to\n" <<
	        "#{' ' * 37}download+install or to use an existing\n" <<
	        "#{' ' * 37}Nginx source directory.") do
		options[:auto_download] = true
	end
	opts.on("--nginx-source-dir=DIR", String, "Compile and install Nginx using the given\n" <<
	        "#{' ' * 37}Nginx source directory, instead of\n" <<
	        "#{' ' * 37}interactively asking to download+install\n" <<
	        "#{' ' * 37}or to use an existing Nginx source\n" <<
	        "#{' ' * 37}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" <<
	        "#{' ' * 37}'configure' script, instead of asking for\n" <<
	        "#{' ' * 37}it interactively. Only applicable if\n" <<
	        "#{' ' * 37}--nginx-source-dir is given. Specify\n" <<
	        "#{' ' * 37}'none' if you do not want to pass\n" <<
	        "#{' ' * 37}additional flags but do not want this\n" <<
	        "#{' ' * 37}installer to ask interactively either.") do |flags|
		options[:extra_configure_flags] = flags
	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).start