# 🎯 CLAUDE.md - WhaleTown Project Instructions

## 1. Project Vision & Context
- **Project**: "WhaleTown" - A 2D top-down pixel art RPG.
- **Engine**: Godot 4.2+ (Strictly NO Godot 3.x syntax).
- **Architecture**: Strictly layered: `_Core` (Framework), `Scenes` (Gameplay), `UI` (Interface).
- **Core Principle**: "Signal Up, Call Down". High decoupling via `EventSystem`.

## 2. 🛠 Command Reference & Setup
- **Input Map (Required Configuration)**:
  - `move_left`, `move_right`, `move_up`, `move_down` (WASD / Arrows)
  - `interact` (E Key / Space)
  - `pause` (ESC)
- **Run Game**: `godot --path .`
- **Run Tests (GUT)**: `godot --headless -s addons/gut/gut_cmdline.gd -gdir=res://tests/ -ginclude_subdirs`
- **Init Structure**: `mkdir -p _Core/managers _Core/systems Scenes/Maps Scenes/Entities Scenes/Components UI/Windows UI/HUD Assets/Sprites tests/unit tests/integration`

## 3. 📂 File Path Rules (STRICT LOWERCASE)
*Claude: Root folders MUST be lowercase. Scripts and Scenes MUST stay together.*
- **Core Managers**: `_Core/managers/[Name].gd`
- **Core Systems**: `_Core/systems/[Name].gd`
- **Entities**: `Scenes/Entities/[EntityName]/[EntityName].tscn` (Script `.gd` in same folder).
- **Maps**: `Scenes/Maps/[map_name].tscn`
- **Components**: `Scenes/Components/[ComponentName].gd` (Reusable logic nodes).
- **UI Windows**: `UI/Windows/[WindowName].tscn`
- **Tests**: `tests/[unit|integration]/test_[name].gd` (Folder is lowercase `tests`).

## 4. 📋 Coding Standards (The Law)
- **Type Safety**: ALWAYS use strict static typing: `var speed: float = 100.0`, `func _ready() -> void`.
- **Naming Conventions**: 
  - `class_name PascalCase` at the top of every script.
  - Variables/Functions: `snake_case`. Constants: `SCREAMING_SNAKE_CASE`.
  - Private members: Prefix with underscore `_` (e.g., `var _health: int`).
- **Node Access**: Use `%UniqueName` for UI and internal scene components.
- **Signals**: Use "Signal Up, Call Down". Parent calls child methods; Child emits signals.
- **Forbidden Patterns**:
  - ❌ NO `yield()` -> Use `await`.
  - ❌ NO `get_node()` in `_process` -> Cache with `@onready`.
  - ❌ NO Linear Filter -> All Sprite2D/TileMap resources MUST use **Nearest** filter.

## 5. 🏛 Architecture & Communication
- **EventSystem**: Use `_Core/systems/EventSystem.gd` for cross-module messaging.
- **Event Registry**: Use `class_name EventNames` in `_Core/EventNames.gd`. 
  ```gdscript
  class_name EventNames
  const PLAYER_MOVED = "player_moved"
  const INTERACT_PRESSED = "interact_pressed"
  const NPC_TALKED = "npc_talked"
Singletons: Only GameManager, SceneManager, EventSystem allowed as Autoloads.
Decoupling: Low-level entities MUST NOT reference GameManager. Use events.
6. 🏗 Implementation Details
Player: CharacterBody2D. Must include Camera2D with position_smoothing_enabled = true.
NPC/Interactables: Use Area2D named InteractionArea. Trigger via EventSystem.
TileMap Layers:
Layer 0: Ground (No collision).
Layer 1: Obstacles (Physics Layer enabled).
Layer 2: Decoration (Y-Sort enabled).
Camera: Must auto-calculate limits via TileMap.get_used_rect().
7. 🧪 Testing Requirements (MANDATORY)
Coverage: Every Manager/System in _Core/ MUST have a GUT test.
Naming: Test files must start with test_ and extend GutTest.
Example:
code
Gdscript
extends GutTest
func test_event_emission():
    var sender = Node.new()
    watch_signals(EventSystem)
    EventSystem.emit_event(EventNames.PLAYER_MOVED, {})
    assert_signal_emitted(EventSystem, "event_raised")
8. 🧘 The Zen of Development
Juice or Death: Every interaction (UI popup, NPC talk) MUST have a Tween placeholder.
Zero Magic Numbers: All speeds/timers MUST be @export or defined in Config/.
Simplicity: If a function does two things, split it.
Back of the Fence: Hidden logic (like ResponseHandler.gd) must be as clean as the HUD.
9. 📝 Code Template (Entity Pattern)
code
Gdscript
extends CharacterBody2D
class_name Player

# 1. Exports & Constants
@export var move_speed: float = 200.0

# 2. Node References
@onready var sprite: Sprite2D = %Sprite2D

# 3. Lifecycle
func _physics_process(delta: float) -> void:
    _move(delta)

# 4. Private Methods
func _move(_delta: float) -> void:
    var dir := Input.get_vector("move_left", "move_right", "move_up", "move_down")
    velocity = dir * move_speed
    move_and_slide()