require "pry/default_commands/ls"
require "pry/default_commands/cd"
require "pry/default_commands/find_method"

class Pry
  module DefaultCommands

    Context = Pry::CommandSet.new do
      import Ls
      import Cd
      import FindMethod

      create_command "whereami" do
        description "Show code surrounding the current context."
        banner <<-BANNER
          Usage: whereami [OPTIONS]
        BANNER

        def setup
          @method = Pry::Method.from_binding(target)
        end

        def process
          if show_method?
            file   = @method.source_file
            start  = @method.source_range.begin
            finish = @method.source_range.end - 1
            marker = binding.eval("__LINE__")
          else
            file   = target.eval("__FILE__")
            start  = target.eval("__LINE__") 
            finish = (args.first && args.first.to_i) || 5
            marker = start
          end

          if invalid_file?(file)
            raise Pry::CommandError, 
            "Cannot find local context. Did you use binding.pry?"
          end

          # TODO: refactor.
          if show_method?
            code = Pry::Code.from_file(file).between(start, finish)
          else
            code = Pry::Code.from_file(file).around(start, finish)
          end

          desc = (@method && @method.name_with_owner) || ""
          
          if !code.empty?
            output.puts "\n#{text.bold('From:')} #{file} @ line #{start}#{desc}:\n\n"
            output.puts code.with_line_numbers.with_marker(marker)
            output.puts
          end
        end

        private 

        def show_method?
          @method && !@method.instance_of?(Pry::Method::Disowned)
        end

        def invalid_file?(file)
          file != Pry.eval_path && 
          (file =~ /(\(.*\))|<.*>/ || file == "" || file == "-e")
        end
      end

      create_command "pry-backtrace", "Show the backtrace for the Pry session." do
        banner <<-BANNER
          Usage:   pry-backtrace [OPTIONS] [--help]

          Show the backtrace for the position in the code where Pry was started. This can be used to
          infer the behavior of the program immediately before it entered Pry, just like the backtrace
          property of an exception.

          (NOTE: if you are looking for the backtrace of the most recent exception raised,
          just type: `_ex_.backtrace` instead, see https://github.com/pry/pry/wiki/Special-Locals)

          e.g: pry-backtrace
        BANNER

        def process
          output.puts "\n#{text.bold('Backtrace:')}\n--\n"
          stagger_output _pry_.backtrace.join("\n")
        end
      end

      command "reset", "Reset the REPL to a clean state." do
        output.puts "Pry reset."
        exec "pry"
      end

      create_command /wtf([?!]*)/, "Show the backtrace of the most recent exception" do
        options :listing => 'wtf?'

        banner <<-BANNER
          Show's a few lines of the backtrace of the most recent exception (also available
          as _ex_.backtrace).

          If you want to see more lines, add more question marks or exclamation marks:

          e.g.
          pry(main)> wtf?
          pry(main)> wtf?!???!?!?

          To see the entire backtrace, pass the -v/--verbose flag:

          e.g.
          pry(main)> wtf -v
        BANNER

        def options(opt)
          opt.on(:v, :verbose, "Show the full backtrace.")
        end

        def process
          raise Pry::CommandError, "No most-recent exception" unless _pry_.last_exception

          output.puts "#{text.bold('Exception:')} #{_pry_.last_exception.class}: #{_pry_.last_exception}\n--"
          if opts.verbose?
            output.puts Code.new(_pry_.last_exception.backtrace, 0, :text).with_line_numbers.to_s
          else
            output.puts Code.new(_pry_.last_exception.backtrace.first([captures[0].size, 0.5].max * 10), 0, :text).with_line_numbers.to_s
          end
        end
      end

      # N.B. using a regular expresion here so that "raise-up 'foo'" does the right thing.
      create_command /raise-up(!?\b.*)/, :listing => 'raise-up' do
        description "Raise an exception out of the current pry instance."
        banner <<-BANNER
          Raise up, like exit, allows you to quit pry. Instead of returning a value however, it raises an exception.
          If you don't provide the exception to be raised, it will use the most recent exception (in pry _ex_).

          e.g. `raise-up "get-me-out-of-here"` is equivalent to:
               `raise "get-me-out-of-here"
                raise-up`

          When called as raise-up! (with an exclamation mark), this command raises the exception through
          any nested prys you have created by "cd"ing into objects.
        BANNER

        def process
          return stagger_output help if captures[0] =~ /(-h|--help)\b/
          # Handle 'raise-up', 'raise-up "foo"', 'raise-up RuntimeError, 'farble' in a rubyesque manner
          target.eval("_pry_.raise_up#{captures[0]}")
        end
      end
    end
  end
end