namespace :db do
  desc "Load environment"
  task :environment do
    if ENV['APP_ENV'] == "test" || ENV["RAILS_ENV"] == "test"
      url = ENV['TEST_DATABASE_URL'] || ENV['TEST_MYSQL_URL']
    else
      url = ENV['DATABASE_URL'] || ENV['MYSQL_URL']
    end

    # some JVM drivers (finagle) don't put user/password in url but as different vars
    # parse url and add user and password to query string as needed
    if url.start_with?("jdbc")
      is_jdbc = true
      base_url = url.gsub(/^jdbc\:/, "")
    else
      is_jdbc = false
      base_url = url
    end

    uri = URI.parse(base_url)
    query = CGI.parse(uri.query)

    if !query.has_key?("user")
      query["user"] = ENV['DATABASE_USERNAME'] || ENV['MYSQL_USERNAME']
    end
    if !query.has_key?("password")
      password = ENV['DATABASE_PASSWORD'] || ENV['MYSQL_PASSWORD']
      query["password"] = password unless password.nil?
    end

    uri.query = URI.encode_www_form(query)

    if is_jdbc
      uri = "jdbc:" + uri.to_s
    end

    ::Sequel::Model.db = ::Sequel.connect(uri)
    ::Sequel::Model.db.extension(:connection_validator)
    ::Sequel::Model.db.pool.connection_validation_timeout = 300
  end

  desc "Generate ruby models for all tables"
  task :generate_models => :environment do
    Sequel::Model.db.tables.each do |table|
      klass_name = table.to_s.camelize.singularize
      klass = Class.new(Sequel::Model(table))
      Object.const_set(klass_name, klass)
      puts "Detected model #{table}"
    end
  end

  desc "Load a console"
  task :console => :generate_models do
    ARGV.clear
    IRB.start
  end

  desc "Show version"
  task :version => :environment do
    version = if Sequel::Model.db.tables.include?(:schema_migrations)
      Sequel::Model.db[:schema_migrations].to_a.reverse.first
    end || {}

    puts "Schema Version: #{version[:filename]}"
  end

  desc "Migrate database"
  task :migrate, [:version] => :environment do |_, args|
    Sequel.extension :migration

    if args[:version]
      puts "Migrating to version #{args[:version]}"
      Sequel::Migrator.run(Sequel::Model.db, "db/migrate", target: args[:version].to_i)
    else
      puts "Migrating to latest"
      Sequel::Migrator.run(Sequel::Model.db, "db/migrate")
    end

    Rake::Task['db:version'].execute
  end

  desc "Rollback database"
  task :rollback, [:version] => :environment do |_, args|
    Sequel.extension :migration

    version = if Sequel::Model.db.tables.include?(:schema_migrations)
      Sequel::Model.db[:schema_migrations].to_a.sort_by{|x| x["filename"]}.reverse[1]
    end || {}

    args.with_defaults(:version => version[:filename])

    Sequel::Migrator.run(Sequel::Model.db, "db/migrate", :target => args[:version].to_i)
    Rake::Task['db:version'].execute
  end

  desc "Perform migration reset (full rollback and migration)"
  task :reset => :environment do
    Sequel.extension :migration

    Sequel::Model.db.loggers = [Logger.new($stdout)]

    Sequel::Migrator.run(Sequel::Model.db, "db/migrate", :target => 0)
    Sequel::Migrator.run(Sequel::Model.db, "db/migrate")
    Rake::Task['db:version'].execute
  end
end