Godot Genre Roguelike

class_name GridPathfinder extends Node

## Specialist AStarGrid2D handler for tile-based roguelikes.
## Prefers Manhattan heuristic for 4-way grid movement.

var _grid := AStarGrid2D.new()

func setup_grid(rect: Rect2i, cell_size: Vector2i, diagonals: bool = false) -> void:
	_grid.region = rect
	_grid.cell_size = cell_size
	
	if diagonals:
		_grid.default_compute_heuristic = AStarGrid2D.HEURISTIC_CHEBYSHEV
		_grid.diagonal_mode = AStarGrid2D.DIAGONAL_MODE_ALWAYS
	else:
		_grid.default_compute_heuristic = AStarGrid2D.HEURISTIC_MANHATTAN
		_grid.diagonal_mode = AStarGrid2D.DIAGONAL_MODE_NEVER
		
	_grid.update()

func set_cell_solid(cell: Vector2i, solid: bool = true) -> void:
	if _grid.region.has_point(cell):
		_grid.set_point_solid(cell, solid)

func get_cell_path(from: Vector2i, to: Vector2i) -> Array[Vector2i]:
	if not _grid.region.has_point(from) or not _grid.region.has_point(to):
		return []
	return _grid.get_id_path(from, to)

extends Node
class_name AsyncTurnManager

## Expert Turn Manager (Godot 4.6).
## Asynchronous loop using 'await' to sync actions and animations.

var entities: Array[Node] = []

func run_turn_loop() -> void:
	while true:
		for entity in entities:
			if not is_instance_valid(entity): continue
			
			# Start entity turn
			entity.begin_turn()
			
			# Expert Pattern: Halt loop until entity emits 'finished'
			# This ensures animations (Tweens) complete before the next turn.
			await entity.turn_finished
			
			if _check_victory(): return

## [SKILL NOTICE]: Use 'await' inside the turn loop to cleanly handle 
## asynchronous actions like movement Tweens and attack animations.

class_name DrunkardsWalk extends RefCounted

## Drunkard's Walk algorithm for carving procedural dungeons.
## Uses Vector2i for discrete grid coordinates and isolated RNG for determinism.

static func generate_map(start_pos: Vector2i, steps: int, rng: RandomNumberGenerator) -> Dictionary:
	var map_data: Dictionary = {}
	var current_pos := start_pos
	
	# 4-way orthogonal directions (standard top-down)
	var directions: Array[Vector2i] = [Vector2i.UP, Vector2i.DOWN, Vector2i.LEFT, Vector2i.RIGHT]
	
	for i in range(steps):
		# Mark current position as floor (using StringName for performance)
		map_data[current_pos] = &"floor"
		
		# Pick a random direction from the RNG instance
		var dir := directions[rng.randi() % directions.size()]
		current_pos += dir
		
	return map_data

# skills/genre-roguelike/scripts/dungeon_generator.gd
extends Node

## Dungeon Generator (Expert Pattern)
## Implements a walker-based procedural generation algorithm.
## Creates organic, connected layouts suitable for roguelikes.

class_name DungeonGenerator

signal generation_complete(rooms: Array, spawn_point: Vector2)

@export var tile_map: TileMapLayer
@export var map_width: int = 50
@export var map_height: int = 50
@export var max_walkers: int = 5
@export var max_steps: int = 400
@export var room_chance: float = 0.2

var rng: RandomNumberGenerator

func generate(seed_val: int) -> void:
    rng = RandomNumberGenerator.new()
    rng.seed = seed_val
    
    tile_map.clear()
    
    var start_pos = Vector2i(map_width / 2, map_height / 2)
    var floor_tiles: Array[Vector2i] = [start_pos]
    var walkers: Array[Vector2i] = [start_pos]
    
    # Drunkard's Walk
    for i in range(max_steps):
        var new_walkers: Array[Vector2i] = []
        for walker in walkers:
            # Move
            var dir = [Vector2i.UP, Vector2i.DOWN, Vector2i.LEFT, Vector2i.RIGHT]
            var move = dir[rng.randi() % 4]
            var new_pos = walker + move
            
            # Clamp to bounds
            new_pos.x = clamp(new_pos.x, 2, map_width - 2)
            new_pos.y = clamp(new_pos.y, 2, map_height - 2)
            
            if new_pos not in floor_tiles:
                floor_tiles.append(new_pos)
            
            # Fork/Kill logic
            if rng.randf() < 0.2 and walkers.size() < max_walkers:
                new_walkers.append(new_pos) # Clone walker
                new_walkers.append(new_pos)
            elif rng.randf() < 0.05 and walkers.size() > 1:
                pass # Kill walker
            else:
                new_walkers.append(new_pos) # Keep walking
        
        walkers = new_walkers
        if walkers.is_empty(): # Safety
            walkers.append(floor_tiles.pick_random())

    # Set Tiles
    for pos in floor_tiles:
        tile_map.set_cell(pos, 0, Vector2i(0, 0)) # Assuming Atlas 0, Coords 0,0 is Floor
        
    # Post-Processing: Walls
    _generate_walls(floor_tiles)
    
    generation_complete.emit(floor_tiles, Vector2(start_pos) * tile_map.tile_set.tile_size.x)

func _generate_walls(floor_tiles: Array[Vector2i]) -> void:
    # Helper to surround floors with walls
    # (Simplified for example)
    pass

## EXPERT USAGE:
## Call generate(seed). Use generated floor_tiles to spawn enemies/loot.

class_name FogManager extends Node2D

## Grid-based Fog of War masker for TileMapLayer.
## Efficiently clears "fog" tiles based on FOV results.

@export var fog_layer: TileMapLayer
@export var fog_atlas_coord := Vector2i(0, 0) # Coordinate of the black tile in tileset
@export var fog_source_id := 0

func initialize_fog(region: Rect2i) -> void:
	if not fog_layer: return
	for x in range(region.position.x, region.end.x):
		for y in range(region.position.y, region.end.y):
			fog_layer.set_cell(Vector2i(x, y), fog_source_id, fog_atlas_coord)

func reveal_cells(visible_cells: Array[Vector2i]) -> void:
	if not fog_layer: return
	for cell in visible_cells:
		# Setting source_id to -1 removes the cell (erases fog)
		fog_layer.set_cell(cell, -1)

class_name FOVCalculator extends Node2D

## High-performance Field-of-View calculation using raycasts.
## Bypasses Area2D overhead by querying PhysicsDirectSpaceState2D directly.

func calculate_fov(player_pos: Vector2, radius: float, targets: Array[Vector2]) -> Array[Vector2]:
	var visible_targets: Array[Vector2] = []
	var space_state := get_world_2d().direct_space_state
	var radius_sq := radius * radius
	
	for target in targets:
		# Early exit for distance
		if player_pos.distance_squared_to(target) > radius_sq:
			continue
			
		# Construct raycast query
		var query := PhysicsRayQueryParameters2D.create(player_pos, target)
		
		# Exclude player to prevent self-collision
		if get_parent() is CollisionObject2D:
			query.exclude = [get_parent().get_rid()]
		
		# If empty, path is clear (visible)
		var result := space_state.intersect_ray(query)
		if result.is_empty():
			visible_targets.append(target)
			
	return visible_targets

class_name StateSerializer extends Node

## JSON-based persistence system for procedurally generated entities.
## Avoids PackedScene bloat for high-variance runtime states.

const SAVE_PATH = "user://run_state.json"

func save_run_state(entities: Array[Node]) -> Error:
	var save_data := []
	for entity in entities:
		if entity.has_method(&"get_save_dict"):
			save_data.append(entity.call(&"get_save_dict"))
            
	var file := FileAccess.open(SAVE_PATH, FileAccess.WRITE)
	if not file:
		return FileAccess.get_open_error()
		
	file.store_string(JSON.stringify(save_data))
	return OK

func load_run_state() -> Array:
	if not FileAccess.file_exists(SAVE_PATH):
		return []
		
	var file := FileAccess.open(SAVE_PATH, FileAccess.READ)
	if not file:
		return []
		
	var test_json_conv = JSON.new()
	var error = test_json_conv.parse(file.get_as_text())
	if error == OK:
		return test_json_conv.get_data()
	return []

# skills/genre-roguelike/scripts/meta_progression_manager.gd
extends Node

## Meta Progression Manager (Expert Pattern)
## Handles persistent data across runs, including currency, unlocks, and stats.
## Uses secure saving/loading to prevent casual tampering.

class_name MetaProgressionManager

signal currency_changed(new_amount: int)
signal upgrade_purchased(upgrade_id: String, new_level: int)

const SAVE_PATH = "user://meta_progression.save"
const SECRET_KEY = "CHANGE_ME_IN_PROD" # Use a proper key management strategy

# Data Structure
var save_data: Dictionary = {
    "currency": 0,
    "total_runs": 0,
    "unlocked_items": [],
    "upgrades": {} # upgrade_id: level
}

func _ready() -> void:
    load_progress()

func add_currency(amount: int) -> void:
    save_data["currency"] += amount
    currency_changed.emit(save_data["currency"])
    save_progress()

func purchase_upgrade(upgrade_id: String, cost: int) -> bool:
    if save_data["currency"] >= cost:
        save_data["currency"] -= cost
        if not save_data["upgrades"].has(upgrade_id):
            save_data["upgrades"][upgrade_id] = 0
        save_data["upgrades"][upgrade_id] += 1
        
        currency_changed.emit(save_data["currency"])
        upgrade_purchased.emit(upgrade_id, save_data["upgrades"][upgrade_id])
        save_progress()
        return true
    return false

func get_upgrade_level(upgrade_id: String) -> int:
    return save_data["upgrades"].get(upgrade_id, 0)

func save_progress() -> void:
    var file = FileAccess.open(SAVE_PATH, FileAccess.WRITE)
    if file:
        var json_str = JSON.stringify(save_data)
        # Simple obfuscation (XOR or base64) to deter casual edits
        # For real security, use FileAccess.open_encrypted_with_pass
        var encrypted = Marshalls.utf8_to_base64(json_str) 
        file.store_string(encrypted)
        file.close()

func load_progress() -> void:
    if not FileAccess.file_exists(SAVE_PATH):
        return

    var file = FileAccess.open(SAVE_PATH, FileAccess.READ)
    if file:
        var encrypted = file.get_as_text()
        var json_str = Marshalls.base64_to_utf8(encrypted)
        var json = JSON.new()
        var parse_result = json.parse(json_str)
        if parse_result == OK:
            save_data = json.data
        else:
            printerr("Save file corrupted!")
        file.close()

## EXPERT USAGE:
## Autoload this script. Call add_currency() at end of run. 
## Check get_upgrade_level() during gameplay to apply buffs.

class_name MetaProgression extends Resource

## Global meta-progression data stored separately from session data.
## Prevents wipe of permanent unlocks upon run permadeath.

@export var global_currency: int = 0
@export var unlocked_ability_ids: Array[StringName] = []
@export var permanent_upgrades: Dictionary = {}

const META_PATH = "user://meta_progression.tres"

func save_global() -> Error:
	return ResourceSaver.save(self, META_PATH)

static func load_global() -> MetaProgression:
	if ResourceLoader.exists(META_PATH):
		return load(META_PATH) as MetaProgression
	return MetaProgression.new()

func increment_currency(amount: int) -> void:
	global_currency += amount
	emit_changed()

extends Resource
class_name MetaStatsResource

## Expert Meta-Progression (Godot 4.6).
## Encrypted persistent stats for cross-run upgrades.

@export var max_health_bonus: int = 0
@export var attack_multiplier: float = 1.0
@export var unlocked_classes: Array[String] = []

const SAVE_PATH = "user://meta_progression.cfg"
const CRYPTO_KEY = "expert_godot_roguelike_key"

func save_stats() -> void:
	var config = ConfigFile.new()
	config.set_value("Meta", "health", max_health_bonus)
	config.set_value("Meta", "attack", attack_multiplier)
	# Expert Pattern: Save encrypted to prevent user tampering
	config.save_encrypted_pass(SAVE_PATH, CRYPTO_KEY)

func load_stats() -> void:
	var config = ConfigFile.new()
	if config.load_encrypted_pass(SAVE_PATH, CRYPTO_KEY) == OK:
		max_health_bonus = config.get_value("Meta", "health", 0)
		attack_multiplier = config.get_value("Meta", "attack", 1.0)

## [SKILL NOTICE]: Always save meta-progression to 'user://' using 
## 'save_encrypted_pass()' to protect the game's economy from easy cheats.

class_name MoveCommand extends RefCounted

## Command pattern object for turn-based movement.
## Encapsulates validation and state changes for easy Undo/Redo or logging.

var _entity: Node2D
var _target_cell: Vector2i
var _previous_cell: Vector2i
var _pathfinder: AStarGrid2D

func _init(entity: Node2D, target: Vector2i, pf: AStarGrid2D) -> void:
	_entity = entity
	_target_cell = target
	_pathfinder = pf
	# Assuming entity has a grid_position property
	if entity.get("grid_position"):
		_previous_cell = entity.grid_position

func execute() -> bool:
	# Validation: Is the cell occupied?
	if _pathfinder and _pathfinder.is_point_solid(_target_cell):
		return false
		
	# Apply state
	if _entity.has_method(&"set_grid_position"):
		_entity.call(&"set_grid_position", _target_cell)
	else:
		_entity.set(&"grid_position", _target_cell)
		
	return true

func undo() -> void:
	if _entity.has_method(&"set_grid_position"):
		_entity.call(&"set_grid_position", _previous_cell)
	else:
		_entity.set(&"grid_position", _previous_cell)

extends Node2D
class_name NoiseDungeonGenerator

## Expert Dungeon Generation (Godot 4.6).
## Uses FastNoiseLite for organic caves and AStarGrid2D for connectivity.

@export var tile_map: TileMapLayer
@export var width: int = 64
@export var height: int = 64
@export var wall_threshold: float = 0.2

var _noise := FastNoiseLite.new()
var _astar := AStarGrid2D.new()

func generate() -> void:
	_noise.seed = randi()
	_noise.noise_type = FastNoiseLite.TYPE_SIMPLEX
	
	_astar.region = Rect2i(0, 0, width, height)
	_astar.update()
	
	for x in range(width):
		for y in range(height):
			var pos = Vector2i(x, y)
			if _noise.get_noise_2d(x, y) > wall_threshold:
				tile_map.set_cell(pos, 0, Vector2i(0,0)) # Wall
				_astar.set_point_solid(pos, true)
			else:
				tile_map.set_cell(pos, 1, Vector2i(1,0)) # Floor

	# Expert Tip: Use _astar.get_id_path() to check connectivity 
	# and carve corridors between isolated noise islands.

## [SKILL NOTICE]: Use 'AStarGrid2D' to validate connectivity in noise-based 
## dungeons. It is highly optimized for 2D grids and corridor carving.

# roguelike_patterns.gd
extends Node

# 1. Initializing AStarGrid2D for Dungeon Pathfinding
# EXPERT NOTE: Prefer AStarGrid2D for grid-based pathfinding; always call update() before use.
func setup_dungeon_grid(rect: Rect2i) -> AStarGrid2D:
    var grid := AStarGrid2D.new()
    grid.region = rect
    grid.diagonal_mode = AStarGrid2D.DIAGONAL_MODE_NEVER
    grid.update() 
    return grid

# 2. Typed Dictionary for Permadeath Save States
# EXPERT NOTE: Enforces strict typing for JSON serialization of your meta-progression.
var meta_progression: Dictionary[StringName, int] = {
    &"total_deaths": 0,
    &"currency": 0
}

# 3. Offloading Procedural Generation
# EXPERT NOTE: Frees the main thread to render loading screens smoothly.
func generate_dungeon_async() -> void:
    WorkerThreadPool.add_task(_compute_dungeon_layout, true, "DungeonGen")

func _compute_dungeon_layout() -> void:
    # Heavy generation logic here
    pass

# 4. Turn-Based State Machine via Pattern Matching
# EXPERT NOTE: Use StringNames and match for optimized state logic.
func process_turn(state: StringName) -> void:
    match state:
        &"player_turn":
            # await player.execute_turn()
            pass
        &"enemy_turn":
            get_tree().call_group(&"enemies", &"take_action")

# 5. Translating Grid Coordinates to World Coordinates
# EXPERT NOTE: Precise mapping from discrete grid cells to smooth world movement.
func move_to_cell(layer: TileMapLayer, coords: Vector2i) -> void:
    var world_pos := layer.map_to_local(coords)
    create_tween().tween_property(self, "position", world_pos, 0.2)

# 6. Deep Duplication of Base Stats
# EXPERT NOTE: Ensures this enemy gets a unique copy of the resource data.
@export var base_stats: Resource
func setup_enemy() -> void:
    if base_stats:
        base_stats = base_stats.duplicate(true) # duplicate(true) is deep in Godot 4

# 7. Modifying TileMapLayers dynamically (Breaking Walls)
# EXPERT NOTE: Update both visuals and navigation logic simultaneously.
func break_wall(layer: TileMapLayer, coords: Vector2i, astar_grid: AStarGrid2D) -> void:
    layer.erase_cell(coords)
    astar_grid.set_point_solid(coords, false)

# 8. Decoupled Combat Logic (Signal Up, Call Down)
# EXPERT NOTE: Use duck-typing with has_method for loosely coupled combat.
func _on_attack_landed(target: Node, damage: int) -> void:
    if target.has_method(&"take_damage"):
        target.call(&"take_damage", damage)

# 9. Extracting Save State via Groups
# EXPERT NOTE: Use Array.map for clean, high-level extraction of save data.
func save_dungeon_state() -> Array[Dictionary]:
    var entities := get_tree().get_nodes_in_group(&"Persist")
    return entities.map(func(node): return node.save() if node.has_method("save") else {})

# 10. Shuffle Bag Randomization for Loot
# EXPERT NOTE: Prevents streaks and ensures variety in item drops.
var _loot_pool: Array[String] = ["potion", "sword", "shield"]
func get_random_loot() -> String:
    if _loot_pool.is_empty(): return ""
    _loot_pool.shuffle()
    return _loot_pool.pop_back()

class_name RoguelikeRNG extends Resource

## Resource for managing seeded randomness and persistence.
## Stores the internal PCG32 state for deterministic reloads.

@export var seed_value: int = 0
var _rng := RandomNumberGenerator.new()

func initialize(new_seed: int) -> void:
	seed_value = new_seed
	_rng.seed = seed_value

func get_generator() -> RandomNumberGenerator:
	return _rng

## Replay-safe state capturing
func save_state() -> int:
	return _rng.state

func load_state(saved_state: int) -> void:
	_rng.seed = seed_value
	_rng.state = saved_state

## Utility for "fair" random using shuffle bag
func get_shuffled_bag(items: Array) -> Array:
	var bag := items.duplicate()
	bag.shuffle()
	return bag

class_name TurnManager extends Node

## Signal-based coordinator for turn-based games.
## Decouples entity logic from global scheduling.

signal turn_started(entity: Node)
signal all_turns_completed

var _entities: Array[Node] = []
var _current_index: int = 0

func register_entity(entity: Node) -> void:
	if not _entities.has(entity):
		_entities.append(entity)
		# Expects entities to have a turn_finished signal
		if entity.has_signal(&"turn_finished"):
			entity.connect(&"turn_finished", _on_entity_turn_finished)

func start_loop() -> void:
	_current_index = 0
	_trigger_turn()

func _on_entity_turn_finished() -> void:
	_current_index += 1
	if _current_index >= _entities.size():
		_current_index = 0
		all_turns_completed.emit()
	
	# Start next turn on next frame to prevent deep recursion
	_trigger_turn.call_deferred()

func _trigger_turn() -> void:
	if _entities.is_empty(): return
	turn_started.emit(_entities[_current_index])

class_name LootTable extends Resource

## Data-driven weighted loot table using Godot 4 native optimization.
## Avoids slow GDScript loops for probability calculation.

@export var items: Array[Resource] = []
@export var weights: PackedFloat32Array = PackedFloat32Array()

## Uses native rand_weighted for O(1) or O(log N) speed depending on size.
func roll_item(rng: RandomNumberGenerator) -> Resource:
	if items.is_empty() or weights.size() != items.size():
		push_error("LootTable: Weights size mismatch or empty items.")
		return null
		
	var rolled_idx := rng.rand_weighted(weights)
	return items[rolled_idx]

func add_entry(item: Resource, weight: float) -> void:
	items.append(item)
	weights.append(weight)