old_table_name = 'internalfirst_message_meta_data_old'
table_name = 'internalfirst_message_meta_data'

id = 169100000;

def process(id, old_table_name, table_name)
  t = Mysql2::Client.new(:host=>"10.85.162.164", :database=>"warehouse_b2b_production", :username=>"wh-2_rw", :password=>"NYvSzh70")
  all_msgs = t.query("select * from #{old_table_name} where id > #{id}")

  all_msgs.each do |msg|
    msg['created_at'] = msg['created_at'].strftime("%Y-%m-%d %H:%M:%S")
    msg['updated_at'] = msg['updated_at'].strftime("%Y-%m-%d %H:%M:%S")
  end

  puts all_msgs.size

  all_msgs.each_slice(1000) do |msgs|
    sql = prepare_insert_sql(table_name, msgs)
    # puts sql
    # puts insert_query
    t.query(sql)
    puts 'Successfully inserted ###'
  end
end



def prepare_insert_sql(table_name, inserts)
  input = {:table_name => table_name, :inserts => inserts}
  validate_insert_sql_construction(input)
  sql = ''
  sql << 'INSERT INTO '
  sql << "#{table_name}"
  column_sql = []
  # Note: Query is constructed based on keys of first
  columns = inserts.first.keys
  columns.each { |column_name| column_sql << "`#{column_name.to_s}`" }
  sql << "(#{column_sql.join(',')}) "
  sql << 'VALUES '
  inserts.each_with_index do |row, index|
    insert_values = []
    columns.each do |column|
      insert_values << if row[column].is_a?(String)
                         "'" + row[column].to_s + "'" #need to see about escaping the string here first
                       elsif row[column].is_a?(NilClass)
                         'NULL'
                       else
                         row[column]
                       end
    end
    sql << "(#{insert_values.join(',')})"
    sql << ', ' unless (index + 1 == inserts.size)
  end
  sql
end

def validate_insert_sql_construction(input)
  validate_presence_of :table_name, :inserts, :in => input, :allow_blank => false, :clause => :insert
end

def validate_presence_of(*args)
  if (options = args[-1]).instance_of? Hash
    map = options[:in] || {}
    blank_check = options[:allow_blank] == false ? true : false
    key_list = args[0..-2]
    clause = options[:clause]
  else
    map, key_list = {}, []
  end

  key_list.each do |key|
    unless map.has_key?(key)
      raise  "'#{key}' parameter is mandatory in '#{clause}' clause"
    end
    if (blank_check && (!is_not_empty?(map[key])))
      raise "'#{key}' parameter can't be blank in '#{clause}' clause"
    end
  end
end

def is_not_empty?(value)
  all_values_present =
      if value.is_a?(Array)
        value.all? do |v|
          v.present?
        end
      else
        value.present?
      end
  value.present? and all_values_present
end


process(id, old_table_name, table_name)