require 'rubygems'
require 'active_record'
require 'FileUtils'

# add a global variable to hold an object to write sql
module ActiveRecord
  class Base
	  ## object which receives strings of sql
		@@write_sql_to = nil

		cattr_accessor :write_sql_to
	end
end

# send log sql to an object
module ActiveRecord
  module ConnectionAdapters # :nodoc:
		class AbstractAdapter

			def log_info(sql, name, ms)
				# log out any SQL to a separate object
				unless ActiveRecord::Base.write_sql_to.nil?
					ActiveRecord::Base.write_sql_to << sql
					ActiveRecord::Base.write_sql_to << ";\n"
				end

        if @logger && @logger.debug?
          name = '%s (%.1fms)' % [name || 'SQL', ms]
          @logger.debug(format_log_entry(name, sql.squeeze(' ')))
        end
      end

		end
	end
end

# capture SQL to a file for migrations
module ActiveRecord
	class Migrator#:nodoc:
		def migrate
			current = migrations.detect { |m| m.version == current_version }
			target = migrations.detect { |m| m.version == @target_version }

			if target.nil? && !@target_version.nil? && @target_version > 0
				raise UnknownMigrationVersionError.new(@target_version)
			end
			
			start = up? ? 0 : (migrations.index(current) || 0)
			finish = migrations.index(target) || migrations.size - 1
			runnable = migrations[start..finish]
			
			# skip the last migration if we're headed down, but not ALL the way down
			runnable.pop if down? && !target.nil?
			
			runnable.each do |migration|
				Base.logger.info "Migrating to #{migration.name} (#{migration.version})"

				# On our way up, we skip migrating the ones we've already migrated
				next if up? && migrated.include?(migration.version.to_i)

				# On our way down, we skip reverting the ones we've never migrated
				if down? && !migrated.include?(migration.version.to_i)
					migration.announce 'never migrated, skipping'; migration.write
					next
				end

				begin
					# where we will write sql to
					filename = "./" + migration.filename.gsub('migrate','sql').gsub('.rb', '_' + @direction.to_s + '.sql').gsub('//','/')
					f = File.new(filename, 'w+')
					ActiveRecord::Base.write_sql_to = f
					
					ddl_transaction do
						migration.migrate(@direction)
						record_version_state_after_migrating(migration.version)
					end

					ActiveRecord::Base.write_sql_to = nil
				rescue => e
					canceled_msg = Base.connection.supports_ddl_transactions? ? "this and " : ""
					raise StandardError, "An error has occurred, #{canceled_msg}all later migrations canceled:\n\n#{e}", e.backtrace
				end
			end
		end
	end
end

# make sure there is a directory for migration sql
if (!File.exists?("./db/sql/") || !File.directory?("./db/sql")) 
	FileUtils.mkdir("./db/sql/")
end