launch_sim.py

#!/usr/bin/env python3
"""
SAFAR — Universal Cross-Platform Simulation Launcher
Detects Webots installation, pre-populates asset cache if needed, and launches the simulation.
Works out-of-the-box on any machine running Windows, macOS, or Linux.
"""

import os
import sys
import shutil
import platform
import subprocess
from pathlib import Path

PROJECT_ROOT = Path(__file__).resolve().parent
WORLD_FILE = PROJECT_ROOT / "webots_sim" / "worlds" / "safar_pothole_track.wbt"

# Ensure offline assets are extracted
from setup_simulation_assets import setup_webots_assets, verify_yolo_weights


def find_webots_executable() -> Path:
    """Finds Webots executable across common operating system locations."""
    system = platform.system()

    # 1. Check WEBOTS_HOME environment variable
    webots_home = os.environ.get("WEBOTS_HOME")
    if webots_home:
        home_path = Path(webots_home)
        candidates = [
            home_path / "msys64" / "mingw64" / "bin" / "webotsw.exe",
            home_path / "msys64" / "mingw64" / "bin" / "webots.exe",
            home_path / "webots",
            home_path / "Webots.app" / "Contents" / "MacOS" / "webots"
        ]
        for c in candidates:
            if c.exists():
                return c

    # 2. Check system PATH
    which_webots = shutil.which("webots") or shutil.which("webots.exe") or shutil.which("webotsw.exe")
    if which_webots:
        return Path(which_webots)

    # 3. Check standard OS paths
    if system == "Windows":
        local_app = os.environ.get("LOCALAPPDATA", "")
        prog_files = os.environ.get("ProgramFiles", "C:\\Program Files")
        standard_windows_paths = [
            Path(local_app) / "Programs" / "Webots" / "msys64" / "mingw64" / "bin" / "webotsw.exe",
            Path(local_app) / "Programs" / "Webots" / "msys64" / "mingw64" / "bin" / "webots.exe",
            Path(prog_files) / "Webots" / "msys64" / "mingw64" / "bin" / "webotsw.exe",
            Path(prog_files) / "Webots" / "msys64" / "mingw64" / "bin" / "webots.exe",
            Path("C:/Program Files/Webots/msys64/mingw64/bin/webotsw.exe")
        ]
        for p in standard_windows_paths:
            if p.exists():
                return p

    elif system == "Darwin":  # macOS
        mac_paths = [
            Path("/Applications/Webots.app/Contents/MacOS/webots"),
            Path.home() / "Applications/Webots.app/Contents/MacOS/webots"
        ]
        for p in mac_paths:
            if p.exists():
                return p

    else:  # Linux
        linux_paths = [
            Path("/usr/local/webots/webots"),
            Path("/usr/bin/webots"),
            Path("/snap/bin/webots")
        ]
        for p in linux_paths:
            if p.exists():
                return p

    return None


def main():
    print("==================================================")
    print("        SAFAR WEBOTS SIMULATION LAUNCHER          ")
    print("==================================================")

    # 1. Verify / extract assets so other devices don't hit "Cannot load asset"
    setup_webots_assets(force=False)
    verify_yolo_weights()

    # 2. Locate Webots executable
    webots_exe = find_webots_executable()
    if not webots_exe:
        print("\n[ERROR] Webots executable could not be found automatically.")
        print("Please install Webots from: https://cyberbotics.com")
        print("Or set the WEBOTS_HOME environment variable to your Webots folder.")
        sys.exit(1)

    if not WORLD_FILE.exists():
        print(f"\n[ERROR] Simulation world not found: {WORLD_FILE}")
        sys.exit(1)

    print(f"\n[SAFAR] Webots found : {webots_exe}")
    print(f"[SAFAR] Launching track: {WORLD_FILE.name}")
    print("==================================================\n")

    # Launch Webots
    try:
        subprocess.Popen([str(webots_exe), str(WORLD_FILE)])
    except Exception as e:
        print(f"[ERROR] Failed to launch Webots: {e}")
        sys.exit(1)


if __name__ == "__main__":
    main()