require 'erb'
require 'fileutils'

require_relative 'shift-lang/generator'
require_relative 'shift-lang/version'

module Shift
	class CLI
		def initialize(args)
			if(!args[0])
				puts "Enter the project name : "
				project_name = gets.chomp

				if(!File.exists?(project_name))
					Dir.mkdir(project_name)
					Dir.chdir(project_name)

					puts "Creating " + project_name + ".shift"
					puts "Creating views directory"
					Dir.mkdir("views")
					file = File.new(project_name + ".shift", "w")
					file.puts ""
					file.close
				else
					puts "A file already exists with the same name"
				end
			else
				case args[0]
				when "generate"
					case args[1]
					when "python"
						generate_python
					when "ruby"
						generate_ruby
					when "javascript"
						generate_javascript
					else
						puts "Unknown target platform. Options are ruby, python and javascript"
					end
				else
					puts "Unknown option"
				end
			end				
		end

		def get_files_from_directory(directory, extension = ".shift", log = true)
			files = []
			Dir.foreach(directory) do | file | 
				if(File.directory?(file) == false)
					file = File.join(directory, file)
					if(File.extname(file) == extension)
						if log
							puts "Found file : " + File.absolute_path(file)
						end
						files.push File.absolute_path(file)
					end
				else
					if ((file.to_s != '.') && (file.to_s != '..'))
						file = File.join(directory, file)
						files.concat get_files_from_directory(file)
					end
				end
			end

			files
		end

		def get_files()
			get_files_from_directory Dir.pwd
		end

		def get_project_name()
			project_name = Dir.pwd.split("/")
			project_name[project_name.length - 1]
		end

		def generate_python()
			files = get_files

			generated_code = Shift::Generator::generatePython(files)

			if generated_code == ""
				return
			end

			project_name = get_project_name

			view_sources = File.absolute_path(File.join(Dir.pwd, "views"))

			gae_sources = File.absolute_path(File.join(File.dirname(__FILE__), "app_engine_templates"))
			pystache = File.join(gae_sources, "pystache")
			config = File.join(gae_sources, "app.yaml")

			config_contents = File.open(config, "r") { |io| io.read }

			config_template = ERB.new(config_contents)

			if(!File.exists?("release"))
				Dir.mkdir("release")
			end
			Dir.chdir("release")

			if(File.exists?("python"))
				FileUtils.remove_dir("python", true)
			end

			Dir.mkdir("python")
			Dir.chdir("python")

			puts "Creating target folder 'release/" + project_name + "'"
			Dir.mkdir(project_name)
			Dir.chdir(project_name)	

			puts "Writing application file"
			File.open(project_name + ".py", "w") do |file|
				file.puts generated_code
			end
			
			puts "Copying templates"
			FileUtils.cp_r(pystache, Dir.pwd)
			FileUtils.cp_r(view_sources, Dir.pwd)

			template_files = get_files_from_directory(File.join(Dir.pwd, "views"), ".html", false)
			template_files.each do | template_file |
				text = File.read(template_file)
				File.open(template_file, "w") { | file | file.puts text.gsub("{{id}}", "{{#key}}{{id}}{{/key}}") }
			end

			puts "Writing Google App Engine configuration file"
			File.open("app.yaml", "w") do |file|
				file.puts config_template.result(binding)
			end
			
			puts "Done."
		end

		def generate_ruby()
			files = get_files

			generated_code = Shift::Generator::generateRuby(files)

			if generated_code == ""
				return
			end
			
			project_name = get_project_name

			view_sources = File.absolute_path(File.join(Dir.pwd, "views"))
			template_sources = File.absolute_path(File.join(File.dirname(__FILE__), "heroku_templates"))
			gemfile = File.join(template_sources, "Gemfile")
			procfile = File.join(template_sources, "Procfile")
			
			if(!File.exists?("release"))
				Dir.mkdir("release")
			end
			Dir.chdir("release")

			if(File.exists?("ruby"))
				FileUtils.remove_dir("ruby", true)
			end

			Dir.mkdir("ruby")
			Dir.chdir("ruby")			

			puts "Creating target folder 'release/" + project_name + "'"
			Dir.mkdir(project_name)
			Dir.chdir(project_name)	

			puts "Writing application file"
			File.open("app.rb", "w") do |file|
				file.puts generated_code
			end
			
			puts "Copying templates"
			FileUtils.cp_r(view_sources, Dir.pwd)

			puts "Generating Heroku configuration files"
			FileUtils.cp(gemfile, Dir.pwd)
			FileUtils.cp(procfile, Dir.pwd)
			
			puts "Done."
		end

		def generate_javascript()
			files = get_files

			generated_code = Shift::Generator::generateJavaScript(files)

			if generated_code == ""
				return
			end

			project_name = get_project_name

			view_sources = File.absolute_path(File.join(Dir.pwd, "views"))
			
			if(!File.exists?("release"))
				Dir.mkdir("release")
			end
			Dir.chdir("release")

			if(File.exists?("javascript"))
				FileUtils.remove_dir("javascript", true)
			end

			Dir.mkdir("javascript")
			Dir.chdir("javascript")			

			puts "Creating target folder 'release/" + project_name + "'"
			Dir.mkdir(project_name)
			Dir.chdir(project_name)	

			puts "Writing application file"
			File.open("app.js", "w") do |file|
				file.puts generated_code
			end
			
			puts "Copying templates"
			FileUtils.cp_r(view_sources, Dir.pwd)
			
			puts "Done."	
		end
	end
end