# ⚡ Logic Gates — Circuit Simulator RPG

A logic gate circuit simulator combined with a Pokemon-style tile-based world. Players explore **Neon Town**, interact with NPCs, and craft logic circuits in a **Workshop** to solve puzzle doors and progress through the game.

**Live:** [logic.montlab.dev](https://logic.montlab.dev)

## 🎮 Game Modes

### World Mode (exploration)
- Walk around pixel-art maps rendered from PNG backgrounds
- Talk to NPCs, read signs, enter buildings through doors
- Find puzzle doors that require specific circuit outputs to unlock
- Open your **backpack** to manage saved gadgets

### Workshop Mode (circuit editor)
- Full-featured logic gate simulator with drag-and-drop
- Gates: AND, OR, NOT, NAND, NOR, XOR, INPUT, OUTPUT, CLOCK
- Wire gates together by dragging between ports
- Real-time simulation with GTKWave-style waveform viewer
- Save circuits as **custom components** for reuse
- Save circuits as **gadgets** to your backpack for use on puzzles

## 🕹️ Controls

### World
| Key | Action |
|-----|--------|
| WASD / Arrows | Move |
| E / Enter / Space | Interact with NPCs, signs, doors |
| I | Open Backpack |
| TAB | Open Workshop |
| F3 | Toggle debug collision overlay |

### Workshop
| Key | Action |
|-----|--------|
| Click + Drag | Place and connect gates |
| Shift + Drag | Cut wires / create bus connectors |
| Mouse wheel | Zoom |
| Arrows / +/- | Pan and zoom |
| 0 | Reset camera |

### Backpack
| Key | Action |
|-----|--------|
| ↑↓ / WS | Navigate gadget list |
| E / Enter | Select → Use / Toss |
| I / ESC / B | Close |

## 🎒 Gadget System

Circuits become portable items:

1. **Build** a circuit in the Workshop with INPUT and OUTPUT gates
2. **Save as Gadget** (pink button, top-right) — names it and stores in your backpack
3. **Use on puzzle doors** — the game runs your circuit's truth table against the puzzle's required outputs
4. If outputs match → puzzle solved, door unlocks!

## 🗺️ Maps

| Map | Size | Description |
|-----|------|-------------|
| Neon Town | 20×18 | Hub town with buildings, NPCs, signs |
| Circuit Lab | 10×12 | Professor's lab with workshop tables |
| House Interior | 8×8 | Generic house (WIP) |
| Route 1 | 20×36 | Path to next area (WIP) |

### Bidirectional Door System
Every door is a two-way link with explicit coordinates — entering a building through a specific door returns you to that exact door when you exit. `spawn` only exists on the starting map (Neon Town).

## 🛠️ Level Editor

Standalone editor at `/editor.html` for visually editing maps:

- **Wall painting** — click/drag to paint collision masks
- **Entity placement** — NPCs, exits, interactions, spawn points
- **🔗 Bi-Link tool** — create bidirectional door links between maps in one click
- **Properties panel** — edit entity properties (dialog, facing, target map/coords)
- **Zoom/pan** — mouse wheel, +/-, arrows, right-click drag
- **Server save/load** — saves directly to `maps.js` via API
- **Keyboard shortcuts** — 1-7 for tools, Ctrl+S to save, Delete to remove

## 📁 Project Structure

```
├── index.html              # Main game page
├── editor.html             # Standalone level editor
├── server.js               # Node.js server (static + API)
├── Dockerfile              # Docker build (node:20-alpine)
├── assets/
│   ├── map/                # PNG map backgrounds (lab, pallet-town, house, route-1)
│   └── character/          # Player sprites (32×32, 4 directions × 3 frames)
│       └── npcs/           # NPC sprites (16×16)
├── css/
│   └── style.css           # Workshop UI styles
├── js/
│   ├── app.js              # Entry point, wires everything together
│   ├── state.js            # Circuit editor state
│   ├── gates.js            # Gate creation and evaluation
│   ├── connections.js      # Wire/connection logic
│   ├── renderer.js         # Circuit editor canvas rendering
│   ├── events.js           # Circuit editor mouse/keyboard events
│   ├── components.js       # Custom component system (save/eval/edit)
│   ├── saveLoad.js         # Circuit serialization
│   ├── levels.js           # Puzzle level definitions
│   ├── constants.js        # Shared constants
│   └── world/
│       ├── gameMode.js     # Mode coordinator (world ↔ workshop)
│       ├── maps.js         # Map definitions (walls, exits, NPCs, interactions)
│       ├── sprites.js      # PNG asset loading and drawing
│       ├── worldRenderer.js# World canvas rendering (map, NPCs, player, HUD, debug)
│       ├── worldInput.js   # World keyboard input (movement, interaction)
│       ├── worldState.js   # World game state (player, dialog, puzzles, gadgets)
│       └── inventory.js    # Gadget backpack (data model + full-screen UI)
```

## 🚀 Development

### Run locally
```bash
npm start          # or: node server.js
# Open http://localhost:3000
```

### Deploy (Docker via Coolify)
```bash
docker build -t logic-gates .
docker run -p 3000:3000 logic-gates
```

Deployed automatically via Coolify on Hetzner at `logic.montlab.dev`.

### API Endpoints
| Method | Endpoint | Description |
|--------|----------|-------------|
| GET | `/api/maps` | Get current maps.js content |
| PUT | `/api/maps` | Update maps.js (creates .bak backup) |

## 🔧 Technical Details

- **Rendering**: Vanilla Canvas 2D, no frameworks
- **Modules**: ES6 modules (`type="module"`)
- **Tile system**: 16px native tiles, 3× scale = 48px on screen
- **Collision**: `Set<"x,y">` for O(1) wall lookups
- **Player sprite**: 32×32 native, drawn at 48×48 (same visual size as 16×16 NPC sprites at 48×48)
- **Camera**: Follows player, centered on screen
- **Movement**: Interpolated tile-based (0.15s per tile)
- **Circuit evaluation**: Fixed-point iteration (max 20 passes) — supports latches/flip-flops