#
# File:: console.rb
# Description:: Console command prompt-like shell implementation.
#
# Author:: David Muir <david.muir@rockstarnorth.com>
# Date:: 13 Novemeber 2008
#

#----------------------------------------------------------------------------
# Uses
#----------------------------------------------------------------------------
require "source/builder/shell/shell"
require 'pipeline/win32/stdin_nonblock_gets'

#----------------------------------------------------------------------------
# Implementation
#----------------------------------------------------------------------------
module Assetbuild
module Builder
module Shell
	
	#
	# == Description
	# Console implementation of the Builder Shell.  This shell creates a 
	# command prompt which acts like a DOS-shell allowing users to 
	# submit commands to the builder application when they have local 
	# access to the machine.
	#
	class Console < ShellBase

		HOST = ENV['COMPUTERNAME']
		USER = ENV['USERNAME']
		attr_reader :active
		attr_reader :commands
		
		def initialize( commands = nil, server = ENV['COMPUTERNAME'], port = CommandQueue::DEFAULT_PORT, prompt = DEFAULT_PROMPT )
			super( server, port )
			@prompt = prompt
			@commands = commands
		end
		
		# 
		# Runs a commmand and waits for it to get a result.
		#
		def run_command( command )
			@active = true
			process_command( command )
			
			result = nil
			# Start result processing loop	
			start_result_processing( HOST, USER ) do |cmdres|				
				result = cmdres.result				
				@active = false # will kill the thread loop
			end	
			
			@queue_thread.join
			
			puts "\n#{result}"
			
			result
		end
		
		#
		# Start the console shell blocking for user input and processing
		# commands as they are entered.
		#
		def start( &block )
			Thread.current[:name] = THREAD_NAME
			@active = true
			
			# Start result processing loop
			start_result_processing( HOST, USER) do |cmdres|
				puts "\nCommand Result : #{cmdres.result}"
				prompt( )
			end
						
			# Command Loop
			puts "\nType 'help' for interactive shell usage."
			while ( @active ) do
				begin
					prompt( )
					command = $stdin.wt_gets().chomp().strip()
					
					process_command( command )

				rescue InvalidCommand => ex
					puts "Command not recognised: #{command}."
				
				rescue Exception => ex
					puts "Unhandled exception in shell loop: #{ex.inspect}"
					puts ex.backtrace.join( "\n" )
				end
			end
		end
		
		def stop( )
			@active = false
		end
		
		def prompt( append = '' )
			print "\n#{Time.now.strftime('%Y-%m-%d %H:%M:%S')}> #{append}"
		end
		
		#---------------------------------------------------------------------------
		# Private
		#---------------------------------------------------------------------------
	private
		THREAD_NAME = '__BuilderFramework_ConsoleShell'
		REGEXP_FORMAT = /([A-Z0-9_ \?]+)/i
		DEFAULT_PROMPT = '> '

		#
		# Process or rather 'enqueue' a command for processing.
		#		
		def process_command( command_string )
			throw ArgumentError.new( 'Invalid command object.' ) \
				unless ( ( command_string.is_a?( String ) ) )
			
			begin
				# Do some very basic regexp authentication on command.
				remd = ( command_string.match( REGEXP_FORMAT ) )
				puts "Unrecognised command format.  Ignored." if ( remd.nil? )
				next if ( remd.nil? )
											
				trailing = command_string.split(" ")
				command_name = trailing.delete_at( 0 )				
				
				command = Command.new(command_name, nil, nil, trailing, nil)
				
				enqueue_command( command, HOST, USER )
			rescue Exception => ex
				puts "Unhandled exception in process_command: #{ex.inspect}"
				puts ex.backtrace.join( "\n" )
			end
		end

	end

end # Shell module
end # Builder module
end # Pipeline module

# console.rb