module Templater
  class File
  
    attr_accessor :name, :source, :destination
  
    # Builds a new file, given the name of the file and its source and destination.
    #
    # === Parameters
    # name<Symbol>:: The name of this template
    # source<String>:: Full path to the source of this template
    # destination<String>:: Full path to the destination of this template
    def initialize(name, source, destination)
      @name = name
      @source = source
      @destination = destination
    end
    
    # Returns the destination path relative to Dir.pwd. This is useful for prettier output in interfaces
    # where the destination root is Dir.pwd.
    #
    # === Returns
    # String:: The destination relative to Dir.pwd
    def relative_destination
      @destination.sub(::Dir.pwd + '/', '')
    end

    # Returns the contents of the source file as a String
    #
    # === Returns
    # String:: The source file.
    def render
      ::File.read(source)
    end

    # Checks if the destination file already exists.
    #
    # === Returns
    # Boolean:: true if the file exists, false otherwise.
    def exists?
      ::File.exists?(destination)
    end
  
    # Checks if the content of the file at the destination is identical to the rendered result.
    # 
    # === Returns
    # Boolean:: true if it is identical, false otherwise.
    def identical?
      exists? && ::FileUtils.identical?(source, destination)
    end
  
    # Renders the template and copies it to the destination.
    def invoke!
      ::FileUtils.mkdir_p(::File.dirname(destination))
      ::FileUtils.copy_file(source, destination)
    end
  
  end
end