require_relative 'db/seed'

module Lanes

    module DB
        extend self

        attr_accessor(:config_file)

        def establish_connection( env = ENV['RAILS_ENV'] || 'development')
            file = config_file || 'config/database.yml'
            config = YAML::load( IO.read( file ) )
            ::ActiveRecord::Base.configurations = config
            self.connect( ::ActiveRecord::Base.configurations[ env ] )
        end

        def connect( configuration )
            ::ActiveRecord::Base.establish_connection( configuration )
        end

        def migration_exists?( file_name ) #:nodoc:
            Dir.glob("#{migrations_dir}/[0-9]*_*.rb").grep(/\d+_#{file_name}.rb$/).first
        end

        def load_seed
            load Pathname.new(__FILE__).dirname.join("../../db/seed.rb")
            Seed.execute!
        end

        def configure_rake_environment
            ActiveRecord::Tasks::DatabaseTasks.seed_loader = Lanes::DB
            env = ENV['RAILS_ENV'] || 'development'
            Lanes::DB.config_file ||= 'config/database.yml'
            ENV['SCHEMA'] ||= 'db/schema.sql'
            ENV['DB_STRUCTURE'] ||= 'db/schema.sql'
            ActiveRecord::Base.schema_format = :sql
            Lanes::DB.establish_connection( env )
            ActiveRecord::Tasks::DatabaseTasks.database_configuration = ActiveRecord::Base.configurations
            ActiveRecord::Tasks::DatabaseTasks.env = 'test'
            ActiveRecord::Tasks::DatabaseTasks.migrations_paths = 'db/migrate'
            ActiveRecord::Tasks::DatabaseTasks.current_config( :config => ActiveRecord::Base.configurations[ env ] )
        end

        def create_migration( migration_name )
            STDERR.puts "Migration #{migration_name} already exists!" and return false if migration_exists?( migration_name )
            migration_number = Time.now.utc.strftime("%Y%m%d%H%M%S")
            migration_file = File.join(migrations_dir, "#{migration_number}_#{migration_name}.rb")
            migration_class = migration_name.split("_").map(&:capitalize).join
            File.open(migration_file, 'w') do |file|
                file.write <<-MIGRATION.strip_heredoc
            class #{migration_class} < ActiveRecord::Migration
                def change
                end
            end
            MIGRATION
            end
        end

        def migrate(version = nil)
            silence_activerecord do
                migration_version = version ? version.to_i : version
                ::ActiveRecord::Migrator.migrate( migrations_dir, migration_version )
            end
        end

        def rollback(step = nil)
            silence_activerecord do
                migration_step = step ? step.to_i : 1
                ::ActiveRecord::Migrator.rollback(migrations_dir, migration_step)
            end
        end

        private

        def migrations_dir
            ::ActiveRecord::Migrator.migrations_paths.first
        end

        def silence_activerecord(&block)
            old_logger = ::ActiveRecord::Base.logger
            ::ActiveRecord::Base.logger = nil
            yield if block_given?
            ::ActiveRecord::Base.logger = old_logger
        end
    end
end