Godot Genre Visual Novel

# skills/genre-visual-novel/scripts/dialogue_ui.gd
extends Control

## Dialogue UI (Expert Pattern)
## Handles typewriter effect, BBCode tags, and user input (skip/advance).

class_name DialogueUI

signal animation_finished

@export var rich_text_label: RichTextLabel
@export var name_label: Label
@export var type_speed: float = 0.05

var full_text: String = ""
var is_typing: bool = false

func show_line(text: String, character_name: String) -> void:
    full_text = text
    if name_label: name_label.text = character_name
    rich_text_label.text = text # Parse BBCode immediately
    rich_text_label.visible_ratio = 0.0
    
    is_typing = true
    var tween = create_tween()
    var duration = text.length() * type_speed
    tween.tween_property(rich_text_label, "visible_ratio", 1.0, duration)
    tween.finished.connect(_on_tween_finished)

func _on_tween_finished() -> void:
    is_typing = false
    animation_finished.emit()

func instant_finish() -> void:
    if is_typing:
        # Kill running tweens on label
        var tweens = get_tree().get_processed_tweens()
        # Find which tween targets the label? Complex.
        # Simpler: unique tween stored
        # But for now, just force visible ratio
        rich_text_label.visible_ratio = 1.0
        is_typing = false
        animation_finished.emit()

func _input(event: InputEvent) -> void:
    if event.is_action_pressed("ui_accept"):
        if is_typing:
            instant_finish()
            get_viewport().set_input_as_handled()

## EXPERT USAGE:
## Connect to Story Manager. Call show_line().
## Handles input to skip typing.

# skills/genre-visual-novel/scripts/story_manager.gd
extends Node

## Story Manager (Expert Pattern)
## Driver for Visual Novels. Parses scripts, manages state, and directs UI.

class_name StoryManager

signal line_advanced(text: String, character: String)
signal options_presented(choices: Array)
signal scene_changed(background: String)

var script_data: Dictionary = {}
var current_index: int = 0
var flags: Dictionary = {}
var history: Array[Dictionary] = []

func load_script_from_json(path: String) -> void:
    var file = FileAccess.open(path, FileAccess.READ)
    if file:
        var json = JSON.new()
        if json.parse(file.get_as_text()) == OK:
            script_data = json.data
            current_index = 0
            _process_current_line()
        else:
            printerr("Invalid JSON script")

func advance() -> void:
    current_index += 1
    _process_current_line()

func _process_current_line() -> void:
    if not script_data.has("lines") or current_index >= script_data["lines"].size():
        return
        
    var line = script_data["lines"][current_index]
    
    # Save history state before processing
    history.append({
        "index": current_index,
        "flags": flags.duplicate(true)
    })
    
    if line.has("background"):
        scene_changed.emit(line["background"])
        
    if line.has("choices"):
        options_presented.emit(line["choices"])
    else:
        var char_name = line.get("character", "")
        var text = line.get("text", "")
        line_advanced.emit(text, char_name)

func select_choice(choice_index: int) -> void:
    var line = script_data["lines"][current_index]
    var choices = line["choices"]
    var selected = choices[choice_index]
    
    if selected.has("flag_updates"):
        for key in selected["flag_updates"]:
            flags[key] = selected["flag_updates"][key]
            
    if selected.has("jump_to"):
        _jump_to_label(selected["jump_to"])
    else:
        advance()

func _jump_to_label(label: String) -> void:
    # Simple linear search for label
    for i in range(script_data["lines"].size()):
         if script_data["lines"][i].get("label") == label:
             current_index = i
             _process_current_line()
             return

## EXPERT USAGE:
## Call load_script_from_json() with a path to a JSON file.
## Connect UI to signals to display text/choices.

# visual_novel_patterns.gd
extends Node

# 1. BBCode-Aware Character Display
# EXPERT NOTE: Animate the visible_ratio while preserving BBCode tags for modern UI feel.
func animate_text(label: RichTextLabel, duration: float) -> void:
    label.visible_ratio = 0.0
    var tween := create_tween()
    tween.tween_property(label, "visible_ratio", 1.0, duration)

# 2. Functional Choice Filtering
# EXPERT NOTE: Efficiently filter available dialogue options based on player flags.
func get_valid_choices(choices: Array, flags: Dictionary) -> Array:
    return choices.filter(func(c): return flags.get(c.get(&"required_flag"), true))

# 3. Dynamic Sprite Layering (Z-Index)
# EXPERT NOTE: Adjust z_index programmatically to ensure the speaking character is always on top.
func focus_character(sprite: Sprite2D) -> void:
    sprite.z_index = 10
    sprite.modulate = Color.WHITE

# 4. Global State Persistence (Config)
# EXPERT NOTE: Save world-flags and relationship stats to a persistent config file.
func save_vn_flags(flags: Dictionary) -> void:
    var cfg := ConfigFile.new()
    for key in flags:
        cfg.set_value("Flags", key, flags[key])
    cfg.save("user://save_data.cfg")

# 5. Resource-Based Dialogue Trees
# EXPERT NOTE: Use custom resources to define branching dialogue nodes without messy JSON.
func process_dialogue_node(node: Resource) -> void:
    var text: String = node.get(&"dialogue_text")
    var choices: Array = node.get(&"choices")
    # Display logic here

# 6. Smooth Background Crossfades
# EXPERT NOTE: Blend between background scenes using a shader or global modulate tween.
func transition_background(bg: CanvasItem, next_tex: Texture2D) -> void:
    var tween := create_tween()
    tween.tween_property(bg, "modulate:a", 0.0, 0.5)
    tween.tween_callback(func(): bg.set(&"texture", next_tex))
    tween.tween_property(bg, "modulate:a", 1.0, 0.5)

# 7. Localized StringName Keys
# EXPERT NOTE: Use StringName for dictionary lookups in high-frequency dialogue systems.
func get_line(id: StringName) -> String:
    return tr(id) # Built-in translation lookup

# 8. Handling Skip/Fast-Forward Input
# EXPERT NOTE: Check for "skip" action to instantly complete text animations.
func _input(event: InputEvent) -> void:
    if event.is_action_pressed(&"ui_accept"):
        # label.visible_ratio = 1.0
        pass

# 9. Autoload Manager for Global State
# EXPERT NOTE: Use a Singleton (Autoload) to keep track of the current active node and flags.
func jump_to_node(id: String) -> void:
    # StateManager.current_node = id
    pass

# 10. Node Cleaning for Scene Transitions
# EXPERT NOTE: Always use queue_free() during scene changes to avoid physics/signal errors.
func clear_stage(container: Node) -> void:
    for child in container.get_children():
        child.queue_free()

# skills/genre-visual-novel/code/vn_rollback_manager.gd
extends Node

## VN Rollback Expert Pattern
## Manages state snapshots for multi-level history undo.

@export var max_history: int = 50

# Array of Dictionaries representing state at each dialogue step
var _history: Array[Dictionary] = []

# Current live state
var game_state: Dictionary = {
    "dialogue_id": "start",
    "flags": {},
    "current_bg": "park",
    "character_positions": {}
}

func take_snapshot() -> void:
    # 1. Recursive Deep Copy of State
    var snapshot = game_state.duplicate(true)
    _history.append(snapshot)
    
    if _history.size() > max_history:
        _history.remove_at(0)

func rollback() -> bool:
    # 2. Multi-Level Undo
    if _history.is_empty(): 
        return false
        
    game_state = _history.pop_back()
    _apply_state()
    return true

func _apply_state() -> void:
    # Logic to restore the world based on game_state
    # E.g. Update UI, hide/show characters, change background
    print("Rollback to: ", game_state.dialogue_id)

func set_flag(flag: String, value: Variant) -> void:
    # 3. Predictable State Mutation
    # Always take a snapshot BEFORE changing global flags.
    take_snapshot()
    game_state.flags[flag] = value

## EXPERT NOTE:
## Use the 'Command Pattern' for non-trivial state changes (like inventory). 
## For 'genre-visual-novel', implement 'Character Sprite Layering' where a 
## single Actor node can have its 'base', 'eyes', 'mouth', and 'clothes' 
## textures swapped independently via game_state variables.
## NEVER hardcode dialogue; use a JSON parser to map game_state.dialogue_id 
## to specific lines in a localization-ready data file.