# karthikraguram/tictactoe architecture

> Architecture diagram of the GitHub repository karthikraguram/tictactoe, generated by GitDiagram from its file tree, README and a sample of source files (last updated 2026-08-12). It is an AI-made overview: check details against the source.

- Interactive diagram: https://gitdiagram.com/karthikraguram/tictactoe
- Repository: https://github.com/karthikraguram/tictactoe

## Overview

#### Purpose and Entry Point
This is a standalone Python implementation of Tic-Tac-Toe. The sole executable and application boundary is `TicTacToe.py`; no package structure, README guidance, external services, or infrastructure are present.

#### Application Structure
`TicTacToe.py` necessarily owns the complete game lifecycle: board representation, player-turn handling, move validation, win/draw evaluation, user interaction, and termination. There are no separate modules or layered service boundaries in the repository.

#### Primary Control Flow
Execution begins in `TicTacToe.py`, initializes a game board, then repeats a turn loop:
1. Render or otherwise expose current board state.
2. Accept a player move.
3. Validate and apply the move.
4. Evaluate winner or draw conditions.
5. Switch player or end the game.

The game ends when a winning line is detected or no legal moves remain.

#### State and Domain Boundary
The central domain state is the 3×3 board plus the active player, both managed within `TicTacToe.py`. Move input is the primary external boundary; board mutation should occur only after validation to preserve legal game state.

#### Runtime and Dependencies
The application runs directly on a Python interpreter using `TicTacToe.py`. The repository indicates no declared third-party dependencies, persistence layer, network APIs, deployment infrastructure, or external runtime services.

Main entry points: [`TicTacToe.py`](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py) (TicTacToe.py)

## Diagram (Mermaid)

```mermaid
flowchart TD

subgraph group_game["Tic-Tac-Toe Game"]
  node_app["TicTacToe.py<br/>application entry point<br/>[TicTacToe.py]"]
  node_board[("Board State<br/>domain state<br/>[TicTacToe.py]")]
  node_turn_loop(("Turn Loop<br/>control flow<br/>[TicTacToe.py]"))
  node_render["Board Rendering<br/>interaction<br/>[TicTacToe.py]"]
  node_move_input["Player Move Input<br/>external boundary<br/>[TicTacToe.py]"]
  node_validation["Move Validation<br/>domain rule<br/>[TicTacToe.py]"]
  node_apply_move["Apply Move<br/>state mutation<br/>[TicTacToe.py]"]
  node_outcome["Win / Draw Evaluation<br/>domain rule<br/>[TicTacToe.py]"]
  node_switch_player["Switch Player<br/>state transition<br/>[TicTacToe.py]"]
  node_termination(("Game Termination<br/>application outcome<br/>[TicTacToe.py]"))
end

node_python{{"Python Interpreter<br/>runtime"}}

node_python -->|"executes"| node_app
node_app -->|"initializes"| node_board
node_app -->|"starts"| node_turn_loop
node_turn_loop -->|"renders"| node_render
node_render -->|"prompts"| node_move_input
node_move_input -->|"submits move"| node_validation
node_validation -->|"valid move"| node_apply_move
node_validation -.->|"invalid move"| node_move_input
node_apply_move -->|"mutates"| node_board
node_apply_move -->|"evaluates"| node_outcome
node_outcome -->|"game continues"| node_switch_player
node_switch_player -->|"updates active player"| node_board
node_switch_player -->|"next turn"| node_turn_loop
node_outcome -->|"win or draw"| node_termination

click node_app "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"
click node_board "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"
click node_turn_loop "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"
click node_render "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"
click node_move_input "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"
click node_validation "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"
click node_apply_move "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"
click node_outcome "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"
click node_switch_player "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"
click node_termination "https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py"

classDef toneNeutral fill:#f8fafc,stroke:#334155,stroke-width:1.5px,color:#0f172a
classDef toneBlue fill:#dbeafe,stroke:#2563eb,stroke-width:1.5px,color:#172554
classDef toneAmber fill:#fef3c7,stroke:#d97706,stroke-width:1.5px,color:#78350f
classDef toneMint fill:#dcfce7,stroke:#16a34a,stroke-width:1.5px,color:#14532d
classDef toneRose fill:#ffe4e6,stroke:#e11d48,stroke-width:1.5px,color:#881337
classDef toneIndigo fill:#e0e7ff,stroke:#4f46e5,stroke-width:1.5px,color:#312e81
classDef toneTeal fill:#ccfbf1,stroke:#0f766e,stroke-width:1.5px,color:#134e4a
class node_app,node_board,node_turn_loop,node_render,node_move_input,node_validation,node_apply_move,node_outcome,node_switch_player,node_termination toneBlue
class node_python toneNeutral
```

## Components

### Tic-Tac-Toe Game

All game logic resides in the single executable.

- [TicTacToe.py](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): application entry point · Owns the complete game lifecycle. · `TicTacToe.py`
- [Board State](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): domain state · The 3×3 board and active player. · `TicTacToe.py`
- [Turn Loop](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): control flow · Repeats turns until a winner or draw. · `TicTacToe.py`
- [Board Rendering](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): interaction · `TicTacToe.py`
- [Player Move Input](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): external boundary · Primary user-facing input boundary. · `TicTacToe.py`
- [Move Validation](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): domain rule · Guards board mutation to preserve legal state. · `TicTacToe.py`
- [Apply Move](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): state mutation · `TicTacToe.py`
- [Win / Draw Evaluation](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): domain rule · Detects winning lines or exhausted legal moves. · `TicTacToe.py`
- [Switch Player](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): state transition · `TicTacToe.py`
- [Game Termination](https://github.com/karthikraguram/tictactoe/blob/master/TicTacToe.py): application outcome · Ends after a win or draw. · `TicTacToe.py`

### Other components

- **Python Interpreter**: runtime

## Connections

- Python Interpreter → TicTacToe.py: executes
- TicTacToe.py → Board State: initializes
- TicTacToe.py → Turn Loop: starts
- Turn Loop → Board Rendering: renders
- Board Rendering → Player Move Input: prompts
- Player Move Input → Move Validation: submits move
- Move Validation → Apply Move: valid move
- Move Validation → Player Move Input: invalid move · Requests another move.
- Apply Move → Board State: mutates
- Apply Move → Win / Draw Evaluation: evaluates
- Win / Draw Evaluation → Switch Player: game continues
- Switch Player → Board State: updates active player
- Switch Player → Turn Loop: next turn
- Win / Draw Evaluation → Game Termination: win or draw