require 'flydata/source'
require 'flydata/source/component'
require 'flydata/source/errors'

module Flydata
module Source

class Sync < Component
  def self.inherited(child_class)
    Source.register(child_class, self)
  end

  # Public Interface: Set up data source
  #
  # Called right after the source instance is created.  Perform one-time setup
  # which is necessary to initialize the source for sync (and sync only)
  #
  # Raises exception when the source does not support sync
  def setup
    raise UnsupportedSourceError,"subclass must implement"
  end

  # Public Interface: Tells if the source support sync or not
  #
  # Returns true if the source supports sync.  No otherwise.
  def supported?
    raise UnsupportedSourceError, "subclass must implement"
  end

  # Public Interface: Table lists
  #
  # Returns lists of tables in a hash.  The following lists will be returned
  #   "tables" : An array of tables currently in sync
  #   "new_tables" : An array of tables for which no generate_table_ddl has been run yet
  #   "invalid_tables" : An array of tables that had an issue starting sync
  def table_lists
    raise UnsupportedSourceError, "subclass must implement"
  end

  # Public Interface: Data Servers
  #
  # Returns a comma separated list of data servers to which the agent sends data
  def data_servers
    raise UnsupportedSourceError, "subclass must implement"
  end

  # Public Interface: Forwarder
  #
  # Returns a forwarder type in string.  Values are 'tcpforwarder' or 'sslforwarder'.
  def forwarder
    raise UnsupportedSourceError, "subclass must implement"
  end

  private

  def setup_table_prefs(prefs)
    if prefs['tables_append_only']
      prefs['tables_append_only'] =
        prefs['tables_append_only'].split(/(?:\s*,\s*|\s+)/).uniq
      prefs['tables'] = (prefs['tables'].to_s.split(/(?:\s*,\s*|\s+)/) +
                         prefs['tables_append_only']).uniq
    else
      prefs['tables'] = prefs['tables'].to_s.split(/(?:\s*,\s*|\s+)/).uniq
    end
    prefs['invalid_tables'] =
      prefs['invalid_tables'].kind_of?(String) ?
        prefs['invalid_tables'].split(/(?:\s*,\s*|\s+)/).uniq : []
    prefs['new_tables'] =
      prefs['new_tables'].kind_of?(String) ?
        prefs['new_tables'].split(/(?:\s*,\s*|\s+)/).uniq : []
  end
end

end
end