DamExchange

MOVE message

This message may be sent by either the Initiator or the Follower. The MOVE message passes a move to the opponent program.

Layout

1 byte	4 bytes	2 bytes	2 bytes	2 bytes	variable length
header	time	from field	to field	number captured	captured pieces

header	message type, always 'M' (upper case)
time	the time in seconds the program used to generate the move, specified in 4 position; if the number of seconds is less than 1000 use leading zeroes, possible values therefore are `0000' to `9999'; in this initial version of DamExchange, entry time is for informational purposes only; in future versions of the DamExchange protocol functionality will be added for synchronizing the game clocks of the two playing programs
from field	the originating field of the move, specified in 2 positions; if from field is less than 10, use a leading zero '0', possible values therefore are `01' to `50'
to field	the destination field of the move, specified in 2 positions; if to field is less than 10, use a leading zero '0', possible values therefore are `01' to `50'
number captured	the number of captured pieces (pieces and kings), specified in positions; if number captured is less than 10, use a leading zero '0', possible values therefore are `00' to `20'; if the move is not a capture move this entry is specified as '00'
captured pieces	the fields, each in 2 positions, of the captured pieces; the order in which the fields are specified is not important; if a field number is less than 10, use a leading zero '0', possible values therefore are `01' to `50' for each field; the number of bytes for this entry is exactly twice the number in number captured; if the move is not a capture move, this entry is empty (0 bytes long)

Example
0----0----1----1----2----2----3----3----4----4----5----5----6----6
0----5----0----5----0----5----0----5----0----5----0----5----0----5
M0012061100
M001205250422122320

The program passes moves 6 - 11 respectivily 5 x 25 (pieces 23, 22, 12 and 20 captured). In both examples the program used 12 seconds to generate the move.

Processing on receipt of a MOVE message

Receipt (by the Initiator or Follower) of a MOVE message can be recognized by its header (upper case 'M').
Entry time may be used for informational purposes.
The program executes the move given by from field, to field, number captured and captured pieces.
The program calculates its counter move and passes it as a MOVE message to the opponent program. In case of a forced move it is also necessary to send that move by means of a MOVE message to the opponent program.
If however the program is unwilling or unable to calculate a counter move, it sends a GAMEEND message in stead of a MOVE message to the opponent program.

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