🎮 Ōkinoko In-A-Row

On-Chain Turn-Based Game Engine — TicTacToe · Connect Four · Gomoku (Swap2) · Squava

Ōkinoko In-A-Row is a fully on-chain, trustless, and deterministic game engine for abstract strategy games. Every move, win condition, and bet payout is validated by the smart contract itself - no servers, no middlemen.

🕹️ Play at: Ōkinoko Terminal
⚖️ Games: TicTacToe · TicTacToe5 · Connect Four · Gomoku (Swap2 Freestyle) · Squava
💰 Fair Play: Optional betting, first move swaps, provable fairness, no rake, no hidden fees.
📜 Tech: WebAssembly (WASM) exports · Binary-optimized storage · Off-chain indexer for UX.

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Players interact through WASM-exported functions using human-readable, |-delimited UTF-8 strings. An external indexer is required for optimal UX and visualization.

🌐 Play in the browser via Ōkinoko Terminal. 🧭 Project ethos: No rake. No hidden fees. 100 % fair. 💖 Donations to tibfox.vsc are always appreciated.

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📦 Supported Game Types

Value	Game	Board	Win Condition	Opening Rule	Special Lose Condition
1	Tic Tac Toe	3 × 3	3 in a row	FMP or Standard	–
2	Connect Four / Vier Gewinnt	6 × 7	4 or more in a row	FMP or Standard	–
3	Gomoku Standard	15 × 15	Exactly 5 in a row	FMP + Swap2 fair opening	–
4	Tic Tac Toe 5	5 × 5	4 or more in a row	FMP or Standard	–
5	Squava	5 × 5	4 or more in a row	FMP or Standard	Lose if 3 in a row
6	Gomoku Freestyle	15 × 15	5+ in a row	FMP + Swap2 opening	–

FMP (First Move Purchase): For greater fairness, the creator can define a “first move cost.” The joiner may pay this optional fee (in the game’s token) to buy the first move. Available only when the game has a bet and therefore a defined asset.

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🧩 Indexers

Ōkinoko stores game data in binary format for gas efficiency. This means game details are not directly queryable via standard GraphQL methods.

An off-chain indexer must parse emitted logs and expose them as structured data. For best results, use the Ōkinoko Terminal — it’s already connected to a wip indexer.

(Avoid the use of g_get, as it consumes significant gas.)

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🚀 Exported Functions

All inputs are |-delimited UTF-8 strings. All return values are strings or nil.

1. g_create — Create a Game

"type|name|0.01"

Returns → <gameId>

The last parameter defines the optional First Move Purchase (FMP) amount. This only applies if the game includes a bet.

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2. g_join — Join a Game

"gameId"

Returns → nil on success

If the joiner pays the FMP amount, they earn the right to move first. For Gomoku, joining automatically enters the Swap2 opening phase.

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3. g_swap — Swap Opening (Gomoku only)

Stage	Input Format	Description
Opening	id|place|row-col-color|row-col-color|row-col-color	First player places 3 stones (2 of one color, 1 of the other)
Swap Choice	id|choose|swap | stay | add (see Extra Stones below)	Second player’s decision
Extra Stones	id|add|row-col-color|row-col-color	If “add” chosen, place 2 additional stones
Final Color	id|color|1 or 2	First player selects their final color

After the Swap2 sequence completes, normal play begins.

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4. g_move — Make a Move

"gameId|row|col"

Automatically validates turns, detects wins/draws, and processes payouts.

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5. g_timeout — Claim Timeout

"gameId"

If an opponent is inactive for 7 days, the caller can claim a timeout win.

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6. g_resign — Resign Game

"gameId"

Caller resigns; opponent is immediately declared the winner.

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7. g_get — Retrieve Game State

"gameId"

Output:

id|type|name|creator|opponent|rows|cols|turn|moves|status|winner|betAsset|betAmount|lastMoveAt|<BoardContent>

BoardContent → row-wise ASCII digits (0=empty, 1=X, 2=O)

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🔄 Unified Game Lifecycle

Create (g_create)
   ↓
Waiting for Player
   ↓ g_join
In Progress
   ↓ (if Gomoku) Swap2 phases
Normal Play (g_move)
   ↓
Win / Draw / Resign / Timeout
   ↓
Finished

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♟ Gomoku Swap2 Freestyle State Machine

stateDiagram-v2
    [*] --> Opening: 1st Player places 3 stones (2 X, 1 O)
    Opening --> 2ndPlayer_SwapChoice: after 3 stones placed
    2ndPlayer_SwapChoice --> NormalPlay: choose stay  (Players stay the same)
    2ndPlayer_SwapChoice --> ExtraPlace: send add placements
    2ndPlayer_SwapChoice --> NormalPlay: choose swap (Players switch)
    ExtraPlace --> 1stPlayer_ColorChoice: 2 extra stones placed (by 2nd Player)
    1stPlayer_ColorChoice --> NormalPlay: creator picks X or O
    NormalPlay --> Finished: 2nd Player always begins

Loading

(In most cases the 1st player is the creator of the game. But in case o FMP the joiner is the 1st player.)

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📄 Example — Gomoku Setup (Swap2 Add → Color 2)

g_create: "3|Gomoku"
g_join:   "0"
g_swap:   "0|place|7-7-1|7-8-2|8-7-1"
g_swap:   "0|add|8-8-2|6-7-1"
g_swap:   "0|color|2"
g_move:   "0|10|7"  ← first normal move (Bob plays X)

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⚙ Status & Turn Codes

Status	Meaning
0	Waiting for Player
1	In Progress
2	Finished

Turn	Player
1	X
2	O

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💰 Optional Betting (Intents)

Field	Meaning
Token	hive or hbd
Limit	Bet amount (float)

• Bets are locked upon creation or joining
• Winner takes the full pot
• Draw splits pot 50 / 50
• No rake — player-first design

If the joiner pays an FMP, that amount transfers to the original first player.

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🔐 Timeout Rules

Parameter	Value
Timeout	7 days
Eligible	Only the waiting player
Effect	Instant win + pot transfer

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📜 License

MIT License — free to use, modify, and build upon.