import json
import os
import shutil
import subprocess
import urllib.request
from functools import partial
from pathlib import Path
from tarfile import TarFile

NODE_MODULES = "node_modules"


def replace(target_path, link_target):
    # Ensure the parent directory of target_path exists
    target_path.parent.mkdir(parents=True, exist_ok=True)

    if target_path.is_symlink():
        if target_path.resolve() == link_target.resolve():
            print(f"Symlink already correct: {target_path} -> {link_target}")
        else:
            print(f"Symlink points to the wrong target. Updating: {target_path}")
            target_path.unlink()
            os.symlink(link_target, target_path)
    elif target_path.exists():
        print(
            f"Path exists but is not a symlink. Removing and replacing: {target_path}"
        )
        if target_path.is_dir():
            shutil.rmtree(target_path)
        else:
            target_path.unlink()
        os.symlink(link_target, target_path)
    else:
        print(f"Creating new symlink: {target_path} -> {link_target}")
        os.symlink(link_target, target_path)

def replace_node_modules(vscode_path, native_path, name):
    replace(target_path=vscode_path / NODE_MODULES / name, link_target=native_path / NODE_MODULES / name)



native_modules = [
    "node-pty",
    "native-watchdog",
    "@vscode/spdlog",
    "@parcel/watcher",
]


def replace_natives(vscode_path, native_path):
    replace = partial(replace_node_modules, vscode_path, native_path)
    for name in native_modules:
        replace(name)

def mk_native_modules(vscode_path: Path, native_path: Path):
    """
    For each native module:
    1. Read VSCode's node_modules package/package.json to retrieve version info
    2. Use npm to install specific versions of the native modules
    """
    native_path.mkdir(parents=True, exist_ok=True)

    # Create package.json if it doesn't exist
    package_json_path = native_path / "package.json"
    if not package_json_path.exists():
        with open(package_json_path, "w") as f:
            json.dump({
                "name": "vscode-native-modules",
                "version": "1.0.0",
                "private": True,
                "dependencies": {}
            }, f, indent=2)

    # Read the existing package.json
    with open(package_json_path, "r") as f:
        package_json = json.load(f)

    # Ensure dependencies object exists
    if "dependencies" not in package_json:
        package_json["dependencies"] = {}

    # For each native module, get its version and add to dependencies
    modules_to_install = []
    for module_name in native_modules:
        module_package_json = vscode_path / NODE_MODULES / module_name / "package.json"
        if module_package_json.exists():
            with open(module_package_json, "r") as f:
                module_info = json.load(f)
                version = module_info.get("version", "latest")
                package_json["dependencies"][module_name] = version
                modules_to_install.append(f"{module_name}@{version}")

    # Write updated package.json
    with open(package_json_path, "w") as f:
        json.dump(package_json, f, indent=2)

    # Install the native modules
    if modules_to_install:
        print(f"Installing native modules: {', '.join(modules_to_install)}")
        subprocess.run(["npm", "install"], cwd=str(native_path), check=True)

def replace_node(vscode_path, node_path):
    """
    Replace the node binary in vscode_path with the one from node_path.
    """
    vscode_node_path = vscode_path / "node"

    # Ensure the parent directory of vscode_node_path exists
    vscode_node_path.parent.mkdir(parents=True, exist_ok=True)

    replace(
        target_path=vscode_node_path,
        link_target=node_path,
    )

def main():
    # Download vscode server

    url = "https://github.com/VSCodium/vscodium/releases/download/1.99.32562/vscodium-reh-web-linux-x64-1.99.32562.tar.gz"  # Replace with the actual URL
    tar_path = "vscode-server.tar.gz"  # Replace with your tar.gz file path

    with urllib.request.urlopen(url) as response:
        with open(tar_path, "wb") as file:
            file.write(response.read())

    vscode_path = (Path(".") / "vscode-server-linux-x64-web").absolute()
    # Extract it (tar.gz)
    with TarFile.open(tar_path, "r:gz") as tar:
        tar.extractall(path=vscode_path)

    
    native_path = (Path(".") / "native_modules").absolute()
    mk_native_modules(
        vscode_path=vscode_path,
        native_path=native_path,
    )

    replace_natives(vscode_path, native_path)
    replace_node(vscode_path, Path(shutil.which("node")))


if __name__ == "__main__":
    main()