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stages/002-expand_spec@1/diff.patch

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+diff --git a/.ai/card-game-spec.md b/.ai/card-game-spec.md
+new file mode 100644
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+@@ -0,0 +1,444 @@
++# Detailed Implementation Spec: Terminal-Based FreeCell Solitaire in Python
++
++This document defines the complete technical specifications, software architecture, game rules, and interface design for a terminal-based FreeCell Solitaire game implemented in Python 3. The game relies on the standard library `curses` module for interactive rendering and must support a headless `--smoke` mode for CI/CD test automation.
++
++---
++
++## 1. Overview and Game Rules
++
++FreeCell is a solitaire card game played with a single standard 52-card deck. Unlike most other solitaire games, almost all deals are solvable because all cards are dealt face-up from the start.
++
++### The Board Layout
++The board consists of three main areas:
++1. **The Tableau**: 8 columns.
++   - Columns 1–4 are dealt 7 cards each.
++   - Columns 5–8 are dealt 6 cards each.
++   - All cards are face-up and overlap vertically so that only their values/suits are visible, except for the bottom-most card which is fully exposed.
++2. **The FreeCells (Open Cells)**: 4 temporary storage slots.
++   - Each slot can hold at most one card of any rank or suit.
++   - Cards in FreeCells can be moved back to the Tableau or to the Foundations.
++3. **The Foundations**: 4 piles, one for each suit (Spades ♠, Hearts ♥, Diamonds ♦, Clubs ♣).
++   - These are built up in ascending order by suit, starting from Ace (A) and ending at King (K).
++   - Once a card is placed in a Foundation pile, it is generally kept there (or can optionally be pulled back if required, though typical play is unidirectional).
++
++### Valid Moves
++* **To FreeCell**: Any single exposed card (the bottom-most card of a Tableau column or a card in another FreeCell) can be moved to an empty FreeCell.
++* **To Tableau (Single Card)**:
++  - An exposed card can be placed on top of the bottom-most card of any Tableau column if the target card has a rank exactly 1 higher and is of the **opposite color** (Red vs. Black).
++  - Any single exposed card can be placed in an empty Tableau column.
++* **To Foundation**:
++  - An Ace of any suit can be moved to an empty Foundation pile.
++  - A card can be placed on a Foundation pile if it matches the pile's suit and has a rank exactly 1 higher than the top card of that pile (e.g., a 4♦ on a 3♦).
++* **Tableau to Tableau (Multi-card Sequence or "Supermove")**:
++  - A valid sequence (ordered descending by rank and alternating in color, e.g., 8♥, 7♠, 6♦) can be moved together from one Tableau column to another.
++  - The maximum size $M$ of a sequence that can be moved depends on the number of empty FreeCells ($F$) and empty Tableau columns ($T$):
++    $$M = (1 + F) \times 2^T$$
++    *Note: If the destination Tableau column is empty, it does not count as "empty" in the exponent $T$ of the formula, because it is the target of the move.*
++
++### Win and Loss Conditions
++* **Win**: All 52 cards are successfully placed in the 4 Foundation piles (each containing 13 cards from Ace to King).
++* **Loss / Stalemate**: No legal moves are possible between the Tableau, FreeCells, and Foundations.
++
++---
++
++## 2. Core Data Structures (The Headless Engine)
++
++To guarantee that the game logic is 100% testable without `curses` or any active terminal context, all game rules, cards, and board state must be encapsulated in a pure Python engine.
++
++### Enums and Basic Types
++
++```python
++from enum import Enum, auto
++from typing import List, Optional, Dict, Tuple, NamedTuple
++import random
++
++class Suit(Enum):
++    SPADES = "♠"
++    HEARTS = "♥"
++    DIAMONDS = "♦"
++    CLUBS = "♣"
++
++    @property
++    def color(self) -> str:
++        if self in (Suit.HEARTS, Suit.DIAMONDS):
++            return "RED"
++        return "BLACK"
++
++class Rank(Enum):
++    ACE = 1
++    TWO = 2
++    THREE = 3
++    FOUR = 4
++    FIVE = 5
++    SIX = 6
++    SEVEN = 7
++    EIGHT = 8
++    NINE = 9
++    TEN = 10
++    JACK = 11
++    QUEEN = 12
++    KING = 13
++
++    @property
++    def symbol(self) -> str:
++        mapping = {
++            Rank.ACE: "A",
++            Rank.JACK: "J",
++            Rank.QUEEN: "Q",
++            Rank.KING: "K"
++        }
++        return mapping.get(self, str(self.value))
++```
++
++### The `Card` Class
++
++```python
++class Card:
++    def __init__(self, rank: Rank, suit: Suit):
++        self.rank: Rank = rank
++        self.suit: Suit = suit
++
++    @property
++    def color(self) -> str:
++        return self.suit.color
++
++    def is_opposite_color(self, other: "Card") -> bool:
++        return self.color != other.color
++
++    def can_be_placed_on_tableau(self, other: "Card") -> bool:
++        """Checks if self can be placed on other (which is on top of a Tableau column)."""
++        return self.is_opposite_color(other) and self.rank.value == other.rank.value - 1
++
++    def __repr__(self) -> str:
++        return f"{self.rank.symbol}{self.suit.value}"
++
++    def __eq__(self, other: object) -> bool:
++        if not isinstance(other, Card):
++            return NotImplemented
++        return self.rank == other.rank and self.suit == other.suit
++```
++
++### Pile Types and Identifiers
++
++Move commands will refer to specific regions of the board. We define a standard naming schema for sources and destinations:
++- **FreeCells**: `F1`, `F2`, `F3`, `F4` (or 0-indexed integer indices `0` to `3` mapped to `F`)
++- **Foundations**: `A1`, `A2`, `A3`, `A4` (or `Foundation_Spades`, etc., mapped to `A`)
++- **Tableau Columns**: `C1` to `C8` (or 0-indexed `0` to `7` mapped to `C`)
++
++```python
++class Move(NamedTuple):
++    src_type: str  # 'C' (Tableau), 'F' (Freecell)
++    src_idx: int   # 0-indexed
++    dst_type: str  # 'C' (Tableau), 'F' (Freecell), 'A' (Foundation)
++    dst_idx: int   # 0-indexed
++    card_count: int = 1  # For sequence moves
++```
++
++### GameState Class
++
++```python
++class GameState:
++    def __init__(self):
++        self.tableau: List[List[Card]] = [[] for _ in range(8)]
++        self.free_cells: List[Optional[Card]] = [None] * 4
++        self.foundations: Dict[Suit, List[Card]] = {
++            Suit.SPADES: [],
++            Suit.HEARTS: [],
++            Suit.DIAMONDS: [],
++            Suit.CLUBS: []
++        }
++        self.history: List[Tuple[List[List[Card]], List[Optional[Card]], Dict[Suit, List[Card]]]] = []
++        self.redo_history: List[Tuple[List[List[Card]], List[Optional[Card]], Dict[Suit, List[Card]]]] = []
++
++    def deal(self, seed: Optional[int] = None) -> None:
++        """Generates, shuffles, and distributes a standard 52-card deck."""
++        deck = [Card(rank, suit) for suit in Suit for rank in Rank]
++        if seed is not None:
++            random.seed(seed)
++        else:
++            random.seed()
++        random.shuffle(deck)
++
++        self.tableau = [[] for _ in range(8)]
++        self.free_cells = [None] * 4
++        self.foundations = {s: [] for s in Suit}
++        self.history.clear()
++        self.redo_history.clear()
++
++        # Deal cards: 7 to columns 0-3, 6 to columns 4-7
++        for idx, card in enumerate(deck):
++            col = idx % 8
++            self.tableau[col].append(card)
++
++    def save_state(self) -> Tuple[List[List[Card]], List[Optional[Card]], Dict[Suit, List[Card]]]:
++        """Creates a deep copy of current piles to push to history."""
++        tableau_copy = [col.copy() for col in self.tableau]
++        free_cells_copy = list(self.free_cells)
++        foundations_copy = {suit: pile.copy() for suit, pile in self.foundations.items()}
++        return (tableau_copy, free_cells_copy, foundations_copy)
++
++    def restore_state(self, state_tuple: Tuple[List[List[Card]], List[Optional[Card]], Dict[Suit, List[Card]]]) -> None:
++        self.tableau, self.free_cells, self.foundations = state_tuple
++
++    def push_history(self) -> None:
++        self.history.append(self.save_state())
++        self.redo_history.clear()
++
++    def undo(self) -> bool:
++        if not self.history:
++            return False
++        self.redo_history.append(self.save_state())
++        self.restore_state(self.history.pop())
++        return True
++
++    def redo(self) -> bool:
++        if not self.redo_history:
++            return False
++        self.history.append(self.save_state())
++        self.restore_state(self.redo_history.pop())
++        return True
++```
++
++---
++
++## 3. Terminal UI Layout (using Curses)
++
++The UI will be formatted to fit standard terminal windows (minimum requirement: 80 columns by 24 lines).
++
++### ASCII Layout Blueprint
++
++```text
++======================= TERMINAL FREECELL =======================
++Moves: 12      Time: 01:45                          [H]elp  [Q]uit
++
++ [ F1 ]  [ F2 ]  [ F3 ]  [ F4 ]        [ ♠ ]   [ ♥ ]   [ ♦ ]   [ ♣ ]
++ [ A♠ ]  [ -- ]  [ -- ]  [ -- ]        [ A♠ ]  [ -- ]  [ -- ]  [ -- ]
++ 
++   1       2       3       4             5       6       7       8
++=================================================================
++  C1      C2      C3      C4      C5      C6      C7      C8
++  K♠      10♦     5♣      8♥      A♦      7♣      Q♠      J♥
++  Q♦      9♣      4♦      7♠      J♣      6♦      10♥     
++  J♣      8♦              6♦              5♠      
++  10♥                                             
++  
++=================================================================
++Command: Move from (e.g. C1): _
++[Error/Notification Bar: Invalid move! Red Jack cannot go on Red Queen.]
++```
++
++### Layout Sections
++1. **Header Bar**: Displays current move count, elapsed timer, game state notifications, and quick keys (`H` for Help, `Q` for Quit, `U` for Undo, `R` for Reset, `N` for New Game).
++2. **Top Deck Row**:
++   - **FreeCells (Left)**: 4 slots showing empty state `[ -- ]` or the card string `[ Q♦ ]`.
++   - **Foundations (Right)**: 4 slots showing the suit symbol for empty stacks `[ ♠ ]`, or the top-most card of the stack `[ K♠ ]`.
++3. **Tableau Columns Row**:
++   - Headers: `C1` to `C8`.
++   - Vertical stacks. Overlapping cards are printed downward.
++   - Selected columns or selected cards must be highlighted in reverse-video or marked with a cursor indicator (e.g., `>` prefix).
++4. **Interactive Command/Status Row**:
++   - Prompts the user for action input if using key sequences.
++   - Highlights error states with high-contrast text.
++
++---
++
++## 4. Input Handling, Navigation, and Commands
++
++To accommodate varying terminal capabilities and user preferences, the program will support **Command Sequences** as its primary interface.
++
++### Keyboard Command Input
++
++The prompt `Command:` accepts simple character-based coordinates to declare source and destination.
++
++1. **Selecting Source & Destination**:
++   - Keys `1` to `8` map directly to Tableau Columns `C1` to `C8`.
++   - Keys `q`, `w`, `e`, `r` map directly to FreeCells `F1`, `F2`, `F3`, `F4`.
++   - Keys `a`, `s`, `d`, `f` map directly to Foundations `A1`, `A2`, `A3`, `A4` (or users can just use `a` for automatic best-fit foundation routing).
++   
++   *Example Gameplay Interaction*:
++   - Pressing `1` selects Column 1. The top card is highlighted.
++   - Pressing `q` immediately moves that card to FreeCell 1 (if empty).
++   - Pressing `2` followed by `3` moves the bottom card (or valid sequence) of Column 2 to Column 3.
++
++2. **Command Actions**:
++   - `u` / `U`: Undo last move.
++   - `r` / `R`: Redo undone move.
++   - `n` / `N`: Deal a completely new game.
++   - `s` / `S`: Restart current game (using same shuffle seed).
++   - `h` / `H`: Toggle help overlay showing game controls and rules.
++   - `esc`: Cancel current selection.
++   - `q` / `Q`: Exit game.
++
++### Cursor-Based (Optional Secondary Interface)
++If arrow keys/WASD navigation is enabled:
++- Arrow keys move a highlighted cursor box across Columns 1-8, Freecells, and Foundations.
++- `Space` / `Enter` selects the active stack.
++- Pressing `Space` / `Enter` on another stack completes the move.
++
++---
++
++## 5. Move and Action Validation
++
++The rules engine must rigidly enforce FreeCell constraints.
++
++### Validation Logic Flow Chart (Engine level)
++
++```python
++def validate_move(state: GameState, move: Move) -> Tuple[bool, str]:
++    """
++    Returns (True, "") if the move is legal, or (False, "reason") if illegal.
++    """
++    # 1. Fetch source card(s)
++    src_cards = get_source_cards(state, move.src_type, move.src_idx, move.card_count)
++    if not src_cards:
++        return False, "Source is empty or invalid."
++
++    # 2. If moving multiple cards, verify they form a valid alternating descending sequence
++    if len(src_cards) > 1:
++        if not is_valid_sequence(src_cards):
++            return False, "Selected cards do not form a valid alternating color descending sequence."
++
++    # 3. Validate Destination
++    if move.dst_type == 'F':  # Destination is FreeCell
++        if move.card_count > 1:
++            return False, "Cannot move a sequence to a FreeCell."
++        if state.free_cells[move.dst_idx] is not None:
++            return False, "Target FreeCell is occupied."
++
++    elif move.dst_type == 'A':  # Destination is Foundation
++        if move.card_count > 1:
++            return False, "Cannot move a sequence to a Foundation."
++        card = src_cards[0]
++        f_pile = state.foundations[card.suit]
++        if not f_pile:
++            if card.rank != Rank.ACE:
++                return False, "Foundations must start with an Ace."
++        else:
++            top_card = f_pile[-1]
++            if card.rank.value != top_card.rank.value + 1:
++                return False, f"Cannot place {card} on {top_card}. Must be next rank up."
++
++    elif move.dst_type == 'C':  # Destination is Tableau
++        dest_col = state.tableau[move.dst_idx]
++        first_src_card = src_cards[0]  # The highest rank card in the sequence being moved
++
++        if not dest_col:
++            # Moving sequence/card to empty tableau column
++            # Verify supermove capacity limit
++            max_allowed = get_max_movable_cards(state, target_is_empty_col=True)
++            if len(src_cards) > max_allowed:
++                return False, f"Insufficient empty FreeCells/Columns to move {len(src_cards)} cards (Max: {max_allowed})."
++        else:
++            dest_card = dest_col[-1]
++            if not first_src_card.can_be_placed_on_tableau(dest_card):
++                return False, f"Cannot place {first_src_card} on {dest_card}. Must be alternating color and rank-1."
++            # Verify supermove capacity limit
++            max_allowed = get_max_movable_cards(state, target_is_empty_col=False)
++            if len(src_cards) > max_allowed:
++                return False, f"Insufficient empty FreeCells/Columns to move {len(src_cards)} cards (Max: {max_allowed})."
++
++    return True, ""
++```
++
++### Auto-Home (Quality of Life)
++To minimize repetitive actions, the engine automatically checks if any exposed cards can be safely moved to foundations.
++A card of rank $R$ and suit $S$ can be safely moved to its foundation if:
++1. It is a legal foundation move.
++2. All cards of rank $R-1$ of the **opposite color** are already in the foundation piles.
++3. All cards of rank $R-2$ of the **same color** are already in the foundation piles.
++
++*Why?* This ensures that no remaining card in the Tableau can possibly require this card as a sequence parent (since any card that could pair with it is already safely homed).
++
++---
++
++## 6. Smoke Mode Implementation
++
++To support automated test execution and code validation in continuous integration (CI) pipelines, the program must implement a **headless smoke mode**.
++
++### Invocation
++```bash
++python3 main.py --smoke
++```
++
++### Headless execution logic
++1. Parse CLI arguments. If `--smoke` is present:
++   - **Do not** initialize `curses` or modify the terminal buffer.
++   - Instantiate the `GameState` engine.
++   - Seed the random generator with a fixed value (e.g., `seed=42`) to guarantee a deterministic state.
++   - Run `state.deal(seed=42)`.
++   - Verify that:
++     - 52 cards are distributed.
++     - Tableau columns have size `[7, 7, 7, 7, 6, 6, 6, 6]`.
++     - FreeCells are empty.
++     - Foundation piles are empty.
++   - Run a sequence of mock moves (e.g., attempt to move a valid card if possible, perform undos, verify validation logic handles both valid and invalid moves).
++   - Cleanly exit with return code `0` on success, or return code `1` (or throw exceptions) if assertions fail.
++
++```python
++# Sketch of main entry-point logic
++import sys
++
++def main():
++    if "--smoke" in sys.argv:
++        print("Running headless smoke tests...")
++        try:
++            state = GameState()
++            state.deal(seed=12345)
++            
++            # Assert initial setup
++            assert sum(len(col) for col in state.tableau) == 52, "Tableau must contain 52 cards"
++            assert len(state.tableau[0]) == 7, "Column 1 must have 7 cards"
++            assert len(state.tableau[7]) == 6, "Column 8 must have 6 cards"
++            assert all(fc is None for fc in state.free_cells), "Freecells must start empty"
++            
++            # Verify move validation logic doesn't crash
++            # e.g., attempt an illegal move and ensure it gets rejected
++            invalid_move = Move('C', 0, 'C', 1, 1)
++            valid, reason = validate_move(state, invalid_move)
++            
++            print("Smoke tests passed successfully.")
++            sys.exit(0)
++        except Exception as e:
++            print(f"Smoke test failed: {e}", file=sys.stderr)
++            sys.exit(1)
++    else:
++        # Run standard interactive curses application
++        import curses
++        curses.wrapper(run_curses_app)
++```
++
++---
++
++## 7. Test Strategy
++
++Comprehensive automated tests must validate the engine rules independently of rendering.
++
++### Test Architecture Blueprint
++
++```text
++tests/
++├── __init__.py
++├── test_card.py         # Card attributes, comparison, color, and suitability checks
++├── test_rules.py        # Single-move checks, sequence checking, supermove limit calculation
++├── test_state.py        # Deal correctness, seed-determinism, Undo/Redo stack preservation
++└── test_integration.py  # Simulation of a short deterministic game sequence to verification of Win/Loss
++```
++
++### Key Test Categories and Mock Scenarios
++1. **The Alternating Descending Rule**:
++   - Try placing Red Jack on Black Queen (Valid).
++   - Try placing Red Jack on Red Queen (Invalid).
++   - Try placing Red Jack on Black 10 (Invalid).
++2. **The Supermove Formula Verification**:
++   - Setup state with $F$ empty Freecells and $T$ empty Tableau columns.
++   - Assert `get_max_movable_cards(state)` yields exactly the mathematical output of $(1 + F) \times 2^T$.
++   - Assert that trying to move a sequence of length $M+1$ gets rejected with a helpful warning message.
++3. **Undo/Redo Integrity**:
++   - Execute a series of moves.
++   - Store historical snapshots.
++   - Assert calling `undo()` restores card values, suits, and counts perfectly.
++   - Assert calling `redo()` reapplies changes perfectly.
++4. **Win State Execution**:
++   - Artificially mock all foundation stacks to contain Aces through Queens.
++   - Make the final 4 moves placing Kings.
++   - Verify `state.is_won()` is triggered exactly on the final King placement.
+diff --git a/status.json b/status.json
+new file mode 100644
+index 000000000..ee6907d7f
+--- /dev/null
++++ b/status.json
+@@ -0,0 +1,3 @@
++{
++  "outcome": "succeeded"
++}
+\ No newline at end of file

stages/002-expand_spec@1/status.json

@@ -0,0 +1,6 @@
+{
+  "outcome": "succeeded",
+  "notes": "Stage completed: expand_spec",
+  "failure_reason": null,
+  "timestamp": "2026-06-04T19:25:56.844045Z"
+}

stages/003-impl_setup@1/prompt.md

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+Goal: Build a terminal-based FreeCell solitaire game in Python
+
+## Completed stages
+- **expand_spec**: succeeded
+  - Model: gemini-3.5-flash, 91.5k tokens in / 10.9k out
+  - Files: .ai/card-game-spec.md, status.json
+
+
+Read .ai/card-game-spec.md.
+
+Create the Python project skeleton under card-game-app/:
+- pyproject.toml with pytest configured
+- main.py entrypoint
+- src/card_game_tui/ package
+- tests/ directory
+- README.md stub
+
+Add minimal importable modules so the project compiles.
+
+Run:
+cd card-game-app && python3 -m py_compile main.py src/card_game_tui/*.py
+
+Write status.json at workspace root: outcome=succeeded if the project skeleton exists and compiles, outcome=failed with failure_reason otherwise.

stages/003-impl_setup@1/provider_used.json

@@ -0,0 +1,5 @@
+{
+  "mode": "agent",
+  "provider": "gemini",
+  "model": "gemini-3.5-flash"
+}

stages/003-impl_setup@1/response.md

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+I have successfully completed the task of setting up the Python project skeleton for the terminal-based FreeCell solitaire game.
+
+Here is a summary of the accomplishments:
+1. **Created `card-game-app/` project structure**:
+   - `pyproject.toml` containing proper project metadata and configured `pytest` settings.
+   - `README.md` stub detailing the setup, execution, and testing commands.
+   - `main.py` entrypoint supporting both the standard interactive `curses` runner and the headless `--smoke` mode.
+   - `src/card_game_tui/` package containing:
+     - `__init__.py`: Package imports.
+     - `engine.py`: Headless engine core containing `Suit`, `Rank`, `Card`, `Move`, `GameState`, and `validate_move()` logic directly aligned with the detailed specification.
+     - `tui.py`: Starter placeholder for curses-based interactive terminal rendering.
+   - `tests/` directory containing complete unit and rules assertion test suites:
+     - `test_card.py`: Testing card logic and comparisons.
+     - `test_rules.py`: Validating single move/rules constraints.
+     - `test_state.py`: Ensuring initial dealing, shuffling, undo, and redo mechanics.
+     - `test_integration.py`: Base integration skeleton.
+
+2. **Verified compilation and functionality**:
+   - Successfully compiled the project using the required command:
+     ```bash
+     cd card-game-app && python3 -m py_compile main.py src/card_game_tui/*.py
+     ```
+   - Successfully verified the headless `--smoke` mode, which asserts correct board dimensions and move validation constraints:
+     ```bash
+     cd card-game-app && python3 main.py --smoke
+     ```
+
+3. **Status updated**:
+   - Recorded `outcome: succeeded` in `/home/daytona/workspace/fabro/status.json`.