Hopefully, sufficient background
Many years ago (40-45), I used to play "Sea War" on a good sized time-share system. It was a text/adventure war game between a couple remote players, played over a 100x100 "board" (ocean) via TTY (or later terminals eventually). Each player had five or six ships of different types and capabilities, and a "Home Base" at some coordinate point in the 'ocean'. The objective was to locate and destroy the opponent's Home Base, IIRC, by launching a nuke/missile from your nuke/missile/radar-ship to the proper coordinates.
This game was definitely not the easily found 'SeaWar' (nor seawar2) game that is little more than an automated version of the common Battleship board game ("You sunk my battleship!"), nor any similar variant. This game allowed players to enter course/direction orders for each ship as well as give firing orders when an opponent ship was sighted. Firing orders had to be given with attention to the course the firing ship was moving since that determined where shells would land.
Different ships had more or less firing power with greater/lesser min/max ranges and different manpower, ammo and fuel supplies. After enough time out at sea, supplies would run low and ships needed to return home to resupply. Fuel is used simply by moving while ammo is used in combat. Manpower can be used by being hit by enemy shells. Structural damage can also need home-port repair.
So, one thing that made it interesting was that you could only input orders when invited by the program. You had no way to know if your remote opponent was getting more 'invites' unless perhaps you kept getting status updates indicating that more and more shells were falling closer to one of your ships. But if you kept a good mental map of your heavy cruiser moving on a heading of 115° and you had reason to think that that last barrage came from 10 miles out due east of the ship, and got an invite, you could enter firing orders that would put your shells right on the probable originating coordinates... depending on whether or not the enemy ship was also moving and in what direction.
It was very likely that enemy ships would all be moving because a weather front could pass by and damage, possibly swamp, a stationary ship.
You had to keep all your ships in mind because the boundaries of the 100x100 grid brought danger of running aground for any moving ship. The one-order-per-invite, with multiple ships needing orders and orders often being used to load another unit of fuel or food or ammo or to repair a unit of damage or get personnel back up to operating level or to try a radar sweep of some grid area with the single ship capable of doing it in hopes of finding where enemy ships might regularly be visiting, kept you busy for such a very simple interface.
And you didn't dare keep a ship in port for long. Stationary ships seen on radar multiple times at the same coordinates was the prime clue about a home port location.
Anyway, maybe as late as 20 years ago, I had at least most of the BASIC programming for the game. I haven't actually dug through everything that I have, but I didn't find it in a couple places I thought it should be.
Sound familiar to anyone? Anyone have an idea if any early source is available?