require 'fileutils'

module Padrino
  module Generators
    module SqlHelpers
      def self.create_db(adapter, user, password, host, database, charset, collation)
        case adapter
        when 'postgres'
          environment = {}
          environment['PGPASSWORD'] = password unless password.nil? || password.empty?

          arguments = []
          arguments << "--encoding=#{charset}" if charset
          arguments << "--host=#{host}" if host
          arguments << "--username=#{user}" if user
          arguments << database

          Process.wait Process.spawn(environment, 'createdb', *arguments)
        when 'mysql', 'mysql2'
          environment = {}
          environment['MYSQL_PWD'] = password unless password.nil? || password.empty?

          arguments = []
          arguments << "--user=#{user}" if user
          arguments << "--host=#{host}" unless %w[127.0.0.1 localhost].include?(host)

          arguments << '-e'
          arguments << "CREATE DATABASE #{database} DEFAULT CHARACTER SET #{charset} DEFAULT COLLATE #{collation}"

          Process.wait Process.spawn(environment, 'mysql', *arguments)
        when 'sqlite', 'sqlite3'
          raise "Database #{database} already exists" if File.file?(database)
          FileUtils.mkdir_p(File.dirname(database))
          File.open(database, 'a') {}
        else
          raise "Adapter #{adapter} not supported for creating databases yet."
        end
      end

      def self.drop_db(adapter, user, password, host, database)
        case adapter
        when 'postgres'
          environment = {}
          environment['PGPASSWORD'] = password unless password.nil? || password.empty?

          arguments = []
          arguments << "--host=#{host}" if host
          arguments << "--username=#{user}" if user
          arguments << database

          Process.wait Process.spawn(environment, 'dropdb', *arguments)
        when 'mysql', 'mysql2'
          environment = {}
          environment['MYSQL_PWD'] = password unless password.nil? || password.empty?

          arguments = []
          arguments << "--user=#{user}" if user
          arguments << "--host=#{host}" unless %w[127.0.0.1 localhost].include?(host)

          arguments << '-e'
          arguments << "DROP DATABASE IF EXISTS #{database}"

          Process.wait Process.spawn(environment, 'mysql', *arguments)
        when 'sqlite', 'sqlite3'
          File.delete(database) if File.file?(database)
        else
          raise "Adapter #{adapter} not supported for dropping databases yet."
        end
      end
    end
  end
end
