ferencd@0: require 'utils'
ferencd@0: require 'gs_logger'
ferencd@0: 
ferencd@0: #
ferencd@0: # This class is responsible for handling all database related requests
ferencd@0: #
ferencd@0: 
ferencd@0: class Database
ferencd@0: 
ferencd@0:   private_class_method :new
ferencd@0: 
ferencd@0:   def Database.initialize
ferencd@0: 
ferencd@0:     @@conn = PG::Connection.new(:dbname => 'mazedb', :user => 'mazedb', :password => 's321851gper')
ferencd@0: 
ferencd@0:     @@conn.prepare('ins_prep_stmt', 'insert into games (level_id, level_number,level_type) values ($1,$2,$3)')
ferencd@0:     @@conn.prepare('sel_for_game_id_prep_stmt', 'select * from games where level_id=$1')
ferencd@0:     @@conn.prepare('sel_level_no_prep_stmt', 'select level_number from games where level_id=$1')
ferencd@0:     @@conn.prepare('upd_prep_stmt', 'update games set level_number=$1 where level_id=$2')
ferencd@0: 
ferencd@0:     $LOG.info 'Database initialized'
ferencd@0:   rescue => ex
ferencd@0:     $LOG.fatal "Exception caught while preparing the statements: #{ex.class.to_s}\n"
ferencd@0:     exit 1
ferencd@0:   end
ferencd@0: 
ferencd@0:   #
ferencd@0:   # Inserts a game ID into the database
ferencd@0:   #
ferencd@0:   def Database.insert_game_id_to_db(game_id, lev_no, gam_type)
ferencd@0:     @@conn.exec_prepared 'ins_prep_stmt', ["#{game_id}", lev_no, gam_type]
ferencd@0:   rescue => ex
ferencd@0:     $LOG.error "Exception caught: #{ex.class.to_s}\n"
ferencd@0:     raise
ferencd@0:   end
ferencd@0: 
ferencd@0:   #
ferencd@0:   # Creates a valid game ID by assuring no duplicates in the database
ferencd@0:   #
ferencd@0:   def Database.create_valid_game_id (game_type)
ferencd@0:     game_id = game_type + Utils.random_string(8)
ferencd@0:     # Create a unique ID for the current level
ferencd@0:     loop do
ferencd@0:       begin
ferencd@0:         res = @@conn.exec_prepared 'sel_for_game_id_prep_stmt', ["#{game_id}"]
ferencd@0:       rescue => ex
ferencd@0:         $LOG.error "Exception caught: #{ex.class.to_s}\n"
ferencd@0:         raise
ferencd@0:       end
ferencd@0: 
ferencd@0:       break if res.cmd_tuples == 0
ferencd@0:       res.clear
ferencd@0:       game_id = 'S' + Utils.random_string(8)
ferencd@0: 
ferencd@0:     end
ferencd@0:     game_id
ferencd@0:   end
ferencd@0: 
ferencd@0:   #
ferencd@0:   # Returns the level to which this gid is associated
ferencd@0:   #
ferencd@0:   def Database.get_db_level_for_gid(gid)
ferencd@0:     level_no = 1
ferencd@0:     loop do
ferencd@0:       begin
ferencd@0:         res = @@conn.exec_prepared 'sel_level_no_prep_stmt', ["#{gid}"]
ferencd@0:       rescue => ex
ferencd@0:         $LOG.error "Exception caught: #{ex.class.to_s}\n"
ferencd@0:         raise
ferencd@0:       end
ferencd@0:       return -1 if res.cmd_tuples == 0
ferencd@0:       level_no = res[0]
ferencd@0:       res.clear
ferencd@0:       break
ferencd@0:     end
ferencd@0:     level_no['level_number'].to_i
ferencd@0:   end
ferencd@0: 
ferencd@0:   #
ferencd@0:   # Updates the level number for the given game ID to reflect th current state
ferencd@0:   #
ferencd@0:   def Database.update_level_number_for_gid(level_number, gid)
ferencd@0:     loop do
ferencd@0:       begin
ferencd@0:         res = @@conn.exec_prepared 'upd_prep_stmt', [level_number, "#{gid}"]
ferencd@0:       rescue => ex
ferencd@0:         $LOG.error "Exception caught: #{ex.class.to_s}\n"
ferencd@0:         raise
ferencd@0:       end
ferencd@0:       break if res.cmd_tuples == 0
ferencd@0:       res.clear
ferencd@0:       break
ferencd@0:     end
ferencd@0:   end
ferencd@0: 
ferencd@0: end