require 'readline'

module Gitenv

  class Controller

    def initialize action, options

      @action = action
      @options = options

      @config = Config.new
    end

    def run

      check_config_file!

      if !File.exists?(config_file) and !repository
        create_config_file!
      end

      load_config_file!

      #@config.from repository
      #check_repository!

      # load dot files by default
      #if @config.actions.empty?
      #  @config.symlink @config.dot_files
      #end

      #check_files!

      renderer = Renderer.new
      @config.actions.each do |a|
        a.each do |impl|
          impl.apply if @action == :apply
          puts renderer.render(impl)
        end
      end
    end

    private

    def create_config_file!

      file = config_file
      unless agree "You have no configuration file (#{file}); do you wish to create one? (y/n) "
        puts
        abort "To use gitenv, you must either create a configuration file\nor specify an environment repository with the -r, --repo option."
      end

      repo = @options.repo || ENV['GITENV_REPO']
      unless repo
        Readline.completion_append_character = '/'
        Readline.completion_proc = Proc.new do |str|
          Dir[str+'*'].grep /^#{Regexp.escape(str)}/
        end
        begin
          repo = Readline.readline('Type the path to your environment repository: ', true)
        rescue Interrupt
          exit 1
        end
      end

      if !repo or repo.strip.empty?
        puts; abort "You must specify an environment repository."
      elsif !File.directory?(File.expand_path(repo))
        puts; abort "No such directory #{repo}."
      end

      config = String.new.tap do |s|
        s << %|\n# Path to your environment repository.|
        s << %|\nrepo "#{repo}"\n|
        s << %|\n# Create symlinks in your home folder.|
        s << %|\nsymlink dot_files\n\n|
      end

      File.open(file, 'w'){ |f| f.write config }

      puts
      puts Paint["Successfully wrote configuration to #{file}", :green]
      puts
    end

    def repository
      @options.repo || @config.from || ENV['GITENV_REPO']
    end

    def config_file
      if @options.config
        File.expand_path @options.config
      elsif ENV['GITENV_CONFIG']
        File.expand_path ENV['GITENV_CONFIG']
      else
        File.expand_path '~/.gitenv.rb'
      end
    end

    def load_config_file!
      file = config_file
      return unless File.exists? file
      contents = File.open(file, 'r').read
      @config.instance_eval contents, file
    end

    def check_files!
      problems = []
      @config.actions.each do |a|
        a.each_file do |f|
          if !File.exists?(f)
            problems << { :file => f, :msg => "does not exist" }
          #elsif !File.file?(f)
          #  problems << { :file => f, :msg => "is not a file" }
          elsif !File.readable?(f)
            problems << { :file => f, :msg => "is not readable" }
          end
        end
      end

      return unless problems.any?

      msg = "There are problems with the following files in your repository:"
      problems.each do |p|
        msg << "\n   #{p[:file]} #{p[:msg]}"
      end
      abort msg
    end

    def check_config_file!
      file = config_file
      return if !File.exists?(file)
      if !File.file?(file)
        abort "#{file} is not a file. It cannot be used as a configuration file."
      elsif !File.readable?(file)
        abort "#{file} is not readable. It cannot be used as a configuration file."
      end
    end

    def check_repository!
      if !@config.from
        msg = "You have not specified an environment repository."
        msg << "\nYou must either use the -r, --repo option or create"
        msg << "\na configuration file (~/.gitenv.rb by default) with"
        msg << "\nthe repo setting."
        abort msg
      end
      return if File.directory? @config.from
      notice = File.exists?(@config.from) ? 'is not a directory' : 'does not exist'
      from = if @options.repo
        "--repo #{@options.repo}"
      elsif ENV['GITENV_REPO']
        "$GITENV_REPO = #{ENV['GITENV_REPO']}"
      else
        %/repo "#{@config.from}"/
      end
      abort "The repository you have specified #{notice}.\n   (#{from})"
    end

    def abort msg, code = 1
      warn Paint[msg, :red]
      exit code
    end
  end
end