fabro(01KT9YT14FHDYA4VTV9DSFG0FY): verify_data (succeeded)

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.ai/verify_data.md

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+# Data Structures and Core Game State Verification Findings
+
+## 1. Overview and Command Execution
+We verified the core card game data structures, domain model classes, and test suite. The compilation and automated test run executed successfully:
+
+```bash
+cd card-game-app && python3 -m pytest tests/ -v && python3 -m py_compile main.py src/card_game_tui/*.py
+```
+
+**Results:**
+- **Pytest:** 13/13 tests passed successfully.
+- **Python Compilation:** All files compiled cleanly without syntax or import errors.
+
+---
+
+## 2. Core Game-State Types Defined
+
+The following models and enum types are defined in `src/card_game_tui/domain.py`:
+
+### Enums
+- **`Suit`**: Enum representing the four suits: `HEARTS` ("H"), `DIAMONDS` ("D"), `CLUBS` ("C"), and `SPADES` ("S"). Includes color classification (`RED` or `BLACK`) and UTF-8 symbols (`♥`, `♦`, `♣`, `♠`).
+- **`Rank`**: Enum representing ranks `ACE` (1) to `KING` (13) with appropriate alphanumeric labels (`A`, `J`, `Q`, `K`, or numeric string).
+- **`LocationType`**: Enum classifying board areas: `TABLEAU`, `FREECELL`, and `FOUNDATION`.
+
+### Core Data Classes & Entities
+- **`Card`**: Frozen dataclass containing `suit` and `rank`, with custom representation `[Rank][Suit]` (e.g., `A♥`, `10♠`).
+- **`Position`**: Frozen dataclass packaging `LocationType` and `index` for explicit target and source identification during gameplay.
+- **`MoveRecord`**: Stores move history containing `from_pos`, `to_pos`, moving cards list (`cards`), and a list of nested, cascaded `auto_moves` resulting from auto-homing.
+- **`Deck`**: Builds a standard 52-card deck, supports deterministic random seeding, and deals cards into the 8 Tableau columns (four columns of 7 cards, four columns of 6 cards).
+- **`GameState`**: Main orchestrator of the board. Holds state for:
+  - 8 Tableau columns
+  - 4 Free cells
+  - Foundations mapped by Suit
+  - Undo/Redo history stacks
+
+---
+
+## 3. Basic & Advanced Operations Verified
+
+### Move Validation and Rules Execution
+- **Single Card Moves:** Correctly validates moving a card to free cells (if empty) and to foundations (Aces first, then sequential cards of the matching suit).
+- **Tableau Placement rules:** Strictly enforces alternating colors and descending ranks (e.g., moving a Red 8 onto a Black 9).
+- **Sequence/Multi-Card Moves:** Computes valid transit capacities based on the exact FreeCell Solitaire formula:
+  $$\text{Max Cards} = (1 + \text{empty\_freecells}) \times 2^{\text{transit\_empty\_tableaus}}$$
+  Tested and verified that moves exceeding this threshold or violating sequential alternating order are rejected.
+
+### Cascade Auto-Homing
+- Safely moves cards to foundations automatically after a successful player move.
+- Avoids preemptive/unsafe auto-homing: a card is only auto-homed if its rank does not exceed $N+1$, where $N$ is the rank of the highest cards of the *opposite* color already placed in foundations. This prevents burying cards that might still be needed as Tableau anchors.
+- Cascades until no further eligible cards can be home-bound.
+
+### Command History (Undo / Redo)
+- Seamlessly reverts and reapplies moves.
+- Accurately tracks nested auto-homed moves so that undoing a player's move rolls back the cascading auto-homing moves in precise reverse order.
+
+---
+
+## 4. Conclusion
+The data model is fully complete, mathematically sound, robustly tested, and perfectly ready for consumption by the TUI layer.