#
# File:: lib/pipeline/scm/perforce_util.rb
# Description:: High-level Perforce utility classes and functions.
#
# Author:: David Muir <david.muir@rockstarnorth.com>
# Date:: 2 December 2009
#
# For monkey-patching functions into the SCM::Perforce class use the 
# perforce_helper.rb instead.
#

#----------------------------------------------------------------------------
# Uses
#----------------------------------------------------------------------------
require 'pipeline/log/log'
require 'pipeline/os/path'

#----------------------------------------------------------------------------
# Monkey-Patching
#----------------------------------------------------------------------------

# Monkey patch the P4::Revision class to allow public access to the 
# attributes member.  This class varies from our documentation quite a bit.
# Ah well.  Thank the Ruby stars for Monkey-Patching goodness.
class P4
	class Revision
		attr_reader :attributes
	end
end

#----------------------------------------------------------------------------
# Implementation
#----------------------------------------------------------------------------
module Pipeline
module SCM

	#
	# == Description
	# High-level Perforce utility classes and functions.
	#
	module PerforceUtil
	
		#
		# Fetch a Perforce file revision at a temporary location.  The
		# temporary location filename is returned.
		#
		# === Example
		# See %TOOLSLIB%/util/perforce/p4_get_revision.rb for an example of
		# this function's usage.
		#
		def PerforceUtil::get_file_revision_temp( log, p4, depotfile, rev )
			throw ArgumentError.new( "Invalid P4 object (#{p4.class})." ) \
				unless ( p4.is_a?( P4 ) )
			throw ArgumentError.new( "Invalid P4::DepotFile object (#{depotfile.class})." ) \
				unless ( depotfile.is_a?( P4::DepotFile ) )
			throw ArgumentError.new( "Invalid P4::Revision object (#{rev.class})." ) \
				unless ( rev.is_a?( P4::Revision ) )
			
			p4.connect() unless ( p4.connected?() )
			
			filename = depotfile.depot_file
			tempclient = "#{p4.user}_get_revision_temp"
			where = p4.run_where( filename ).shift()
			target = OS::Path::get_directory( where['clientFile'].gsub( p4.client, tempclient ) )
			target = OS::Path::combine( target, '_Get', OS::Path::get_filename( filename ) )
			localnewfilename = nil
			p4new = P4::new()
			
			begin							
				PerforceUtil_Private::create_single_file_workspace( log, p4, p4.client, tempclient, filename, target )
				
				# Sync the file into the new client.
				p4new.port = p4.port
				p4new.client = tempclient
				p4new.user = p4.user
				p4new.connect( ) unless ( p4new.connected?() )
				
				puts "REV: #{rev.inspect}"
				revision = rev.attributes['rev'].to_s
				newfilenamewithrev = "#{filename}##{revision}"
				log.info( "Syncing: #{newfilenamewithrev}." )
				p4new.run_sync( '-f', newfilenamewithrev )
				localfilename = p4new.run_where( filename ).shift()['path']
				localnewfilename = OS::Path::combine( OS::Path::get_directory( localfilename ), OS::Path::get_basename( localfilename ) ) + "##{revision}.#{OS::Path::get_extension(localfilename)}"
				log.info( "Synced.  Moving file to: #{localnewfilename}." )
				FileUtils::move( localfilename, localnewfilename )
				
			ensure
				p4new.disconnect( )
				PerforceUtil_Private::destroy_workspace( log, p4, tempclient )
			end
			localnewfilename
		end
	
		#--------------------------------------------------------------------
		# Private
		#--------------------------------------------------------------------
	private
		# Private Module.
		module PerforceUtil_Private
		
			# Create a new user workspace that maps a single source file/dir 
			# to a single target file/dir.
			def PerforceUtil_Private::create_single_file_workspace( log, p4, template, name, source, target )
				log.info( "Creating Perforce client: #{name}." )
				curr_client = p4.fetch_client( template )
				new_client = p4.fetch_client( name )
				new_client['Root'] = curr_client['Root']
				new_client['Description'] = "Created by #{OS::Path::get_basename(__FILE__)}."
				new_client_view = P4::Map::new( new_client._view )
				new_client_view.clear( )
				new_client_view.insert( source, target )
				new_client['View'] = new_client_view.to_a
				p4.save_client( new_client )
				
				curr_client
			end
			
			# Destroy a user workspace.  This will fail if the user has files
			# checked-out.
			def PerforceUtil_Private::destroy_workspace( log, p4, name )
				log.info( "Destroying Perforce client: #{name}." )
				p4.delete_client( name )
			end
		end
	
	end # PerforceUtil module

end # SCM module
end # Pipeline module

# lib/pipeline/scm/perforce_util.rb