# Implementation Plan - Phase 1: Dungeon Generation

## Goal Description
Build a robust, data-driven procedural dungeon generator that supports campaign-specific requirements (custom exits vs. objective rooms). This logic will be decoupled from the 3D visualization to ensure testability.

## Architecture
The engine will consist of three main components:
1.  **Tile Registry**: Definitions of all available board sections (Rooms, Corridors, T-Junctions, Corners).
2.  **Dungeon Deck**: A deck manager that handles the probability of drawing specific room types.
3.  **Generator Core**: The state machine that places tiles on a virtual grid.

## User Review Required
> [!IMPORTANT]
> **Campaign Logic Deviation**: The rulebook specifies random dungeons. We are implementing a constrained "Mission" system where:
> *   Current functionality must support "Forced Exits" after X tiles for early campaign missions.
> *   Final missions revert to standard "Objective Room" search.

## Proposed Changes

### [COMPLETED] `src/engine/dungeon/`
We structured the engine effectively.

#### [DONE] `TileDefinitions.js`
-   **Data Structure**: Updated to use Object Map & Single Anchor Points for alignment correction.

#### [DONE] `DungeonDeck.js`
-   Handles the stack of cards.
-   Methods: `draw()`, `shuffle()`, `insert()`.

#### [DONE] `DungeonGenerator.js`
-   **Grid System**: `GridSystem.js` handles collision & spatial logic.
-   **Algorithm**:
    1.  Place Entry Room at (0,0).
    2.  Step-by-Step generation implemented (currently automatic 1s delay).
    3.  **Refinement**: Automatic generation shows alignment issues due to random nature. **Plan Change**: Moving to Manual Player Exploration next.

### Campaign Integration
-   **Mission Config Payload**:
    ```javascript
    {
        missionId: "mission_1",
        objectiveId: "room_dungeon", // Simplified for now
        specialRules: {}
    }
    ```

## Verification Plan
### Automated Tests
-   **Unit Tests**: Verify `Generator` can place tiles without overlapping.
-   **Logic Tests**: Verify "Exit functionality" triggers correctly after N tiles.