app.py

# app.py
import streamlit as st
import streamlit.components.v1 as components
import os
import json
import pandas as pd
import uuid
from PIL import Image, ImageDraw # For minimap (using buttons instead now)
from streamlit_js_eval import streamlit_js_eval, sync # For JS communication

# --- Constants ---
SAVE_DIR = "saved_worlds"
PLOT_WIDTH = 50.0 # Width of each plot in 3D space (adjust as needed)
CSV_COLUMNS = ['obj_id', 'type', 'pos_x', 'pos_y', 'pos_z', 'rot_x', 'rot_y', 'rot_z', 'rot_order']

# --- Ensure Save Directory Exists ---
os.makedirs(SAVE_DIR, exist_ok=True)

# --- Helper Functions ---

@st.cache_data(ttl=3600) # Cache plot list for an hour, or clear manually
def load_plot_metadata():
    """Scans save dir, sorts plots, calculates metadata."""
    plots = []
    plot_files = sorted([f for f in os.listdir(SAVE_DIR) if f.endswith(".csv")])

    current_x_offset = 0.0
    for i, filename in enumerate(plot_files):
        # Extract name - assumes format like 'plot_001_MyName.csv' or just 'plot_001.csv'
        parts = filename[:-4].split('_') # Remove .csv and split by underscore
        plot_id = parts[0] # Assume first part is ID/order
        plot_name = " ".join(parts[1:]) if len(parts) > 1 else f"Plot {i+1}"

        plots.append({
            'id': plot_id,
            'name': plot_name,
            'filename': filename,
            'x_offset': current_x_offset
        })
        current_x_offset += PLOT_WIDTH
    return plots, current_x_offset # Return plots and the next available offset

def load_plot_objects(filename, x_offset):
    """Loads objects from a CSV, applying the plot's x_offset."""
    file_path = os.path.join(SAVE_DIR, filename)
    objects = []
    try:
        df = pd.read_csv(file_path)
        if not all(col in df.columns for col in CSV_COLUMNS):
             st.warning(f"CSV '{filename}' missing expected columns. Skipping.")
             return []

        for _, row in df.iterrows():
            obj_data = row.to_dict()
            # Apply world offset
            obj_data['pos_x'] += x_offset
            objects.append(obj_data)
        return objects
    except FileNotFoundError:
        st.error(f"File not found during object load: {filename}")
        return []
    except pd.errors.EmptyDataError:
         st.info(f"Plot file '{filename}' is empty.")
         return [] # Empty file is valid
    except Exception as e:
        st.error(f"Error loading objects from {filename}: {e}")
        return []


def save_plot_data(filename, objects_data_list, plot_x_offset):
    """Saves object data list to a new CSV file, making positions relative."""
    file_path = os.path.join(SAVE_DIR, filename)
    relative_objects = []
    for obj in objects_data_list:
        # Ensure required fields exist before proceeding
        if not all(k in obj for k in ['position', 'rotation', 'type', 'obj_id']):
            print(f"Skipping malformed object during save: {obj}")
            continue

        relative_obj = {
            'obj_id': obj.get('obj_id', str(uuid.uuid4())), # Generate ID if missing
            'type': obj.get('type', 'Unknown'),
            'pos_x': obj['position'].get('x', 0.0) - plot_x_offset, # Make relative
            'pos_y': obj['position'].get('y', 0.0),
            'pos_z': obj['position'].get('z', 0.0),
            'rot_x': obj['rotation'].get('_x', 0.0),
            'rot_y': obj['rotation'].get('_y', 0.0),
            'rot_z': obj['rotation'].get('_z', 0.0),
            'rot_order': obj['rotation'].get('_order', 'XYZ')
        }
        relative_objects.append(relative_obj)

    try:
        df = pd.DataFrame(relative_objects, columns=CSV_COLUMNS)
        df.to_csv(file_path, index=False)
        st.success(f"Saved plot data to {filename}")
        return True
    except Exception as e:
        st.error(f"Failed to save plot data to {filename}: {e}")
        return False

# --- Page Config ---
st.set_page_config(
    page_title="Shared World Builder",
    layout="wide"
)

# --- Initialize Session State ---
if 'selected_object' not in st.session_state:
    st.session_state.selected_object = 'None'
if 'new_plot_name' not in st.session_state:
    st.session_state.new_plot_name = ""
if 'save_request_data' not in st.session_state: # To store data back from JS
    st.session_state.save_request_data = None

# --- Load Plot Metadata ---
# Cached function returns list of plots and the next starting x_offset
plots_metadata, next_plot_x_offset = load_plot_metadata()

# --- Load ALL Objects for Rendering ---
# This could be slow with many plots! Consider optimization later.
all_initial_objects = []
for plot in plots_metadata: