# Copyright (c) 2022-2025, The Isaac Lab Project Developers (https://github.com/isaac-sim/IsaacLab/blob/main/CONTRIBUTORS.md).
# All rights reserved.
#
# SPDX-License-Identifier: BSD-3-Clause

"""This script sets up the vs-code settings for this project.

This script merges the extraPaths from the "{ISAACSIM_DIR}/.vscode/settings.json" file into
the ".vscode/settings.json" file to enable code completion, go to definition, and other code navigation features
and a default python interpreter set to the isaac-sim python.sh script.

NOTE: This script is not specific to VSCode - it also supports Cursor.
"""

import os
import pathlib
import platform
import re
import sys

# Path to the the project directory
PROJECT_DIR = pathlib.Path(__file__).parents[2]


def get_isaacsim_dir() -> str:
    """Get the location of the Isaac Sim directory via the following methods:

    1. Try to import isaacsim, and use __file__ to get the directory
    2. If that fails, try to get the ISAAC_PATH environment variable
    3. If that fails, return None

    Returns:
        The Isaac Sim directory if found, otherwise None.

    """
    try:
        import isaacsim

        isaacsim_dir = pathlib.Path(isaacsim.__file__).parents[2]
        print(f"Found Isaac Sim directory via importing isaacsim: {isaacsim_dir}")
    except ModuleNotFoundError or ImportError:
        isaacsim_dir = os.environ.get("ISAAC_PATH")

        if isaacsim_dir is None:
            print(
                "ISAAC_PATH is not set. Please set the ISAAC_PATH environment variable to the root of your local Isaac"
                " Sim installation / clone if you want to use python language server with Isaac Sim imports."
            )
            return None

        if not os.path.exists(isaacsim_dir):
            raise FileNotFoundError(
                f"Could not find the isaac-sim directory: {isaacsim_dir} specified via ISAAC_PATH. Please provide the"
                " correct path to the Isaac Sim installation."
            )

        print(f"Found Isaac Sim directory via ISAAC_PATH: {isaacsim_dir}")

    return isaacsim_dir


def read_vscode_settings(vscode_filename: str) -> str:
    """Read VSCode settings from a file.

    Args:
        vscode_filename: Path to the VSCode settings file.

    Returns:
        The contents of the settings file as a string.
    """
    with open(vscode_filename) as f:
        return f.read()


def extract_extra_paths(vscode_settings: str) -> list[str]:
    """Extract extraPaths from VSCode settings.

    Args:
        vscode_settings: The VSCode settings content as a string.

    Returns:
        List of path names from the extraPaths setting.
    """
    # search for the python.analysis.extraPaths section and extract the contents
    settings_match = re.search(
        r"\"python.analysis.extraPaths\": \[.*?\]", vscode_settings, flags=re.MULTILINE | re.DOTALL
    )
    if not settings_match:
        # as a fallback,search for the cursorpyright.analysis.extraPaths section and extract the contents
        settings_match = re.search(
            r"\"cursorpyright.analysis.extraPaths\": \[.*?\]", vscode_settings, flags=re.MULTILINE | re.DOTALL
        )

    if not settings_match:
        return []

    settings = settings_match.group(0)
    settings = settings.split('"python.analysis.extraPaths": [')[-1]
    settings = settings.split("]")[0]

    # read the path names from the settings file
    path_names = settings.split(",")
    path_names = [path_name.strip().strip('"') for path_name in path_names]
    path_names = [path_name for path_name in path_names if len(path_name) > 0]

    return path_names


def process_path_names(path_names: list[str], source_dir: str, target_dir: str = None) -> list[str]:
    """Process path names to be relative to the target directory.

    Args:
        path_names: List of path names to process.
        source_dir: The source directory (relative to which paths are currently defined).
        target_dir: The target directory (relative to which paths should be defined).
                   If None, uses PROJECT_DIR.

    Returns:
        List of processed path names.
    """
    if target_dir is None:
        target_dir = PROJECT_DIR

    # change the path names to be relative to the target directory
    rel_path = os.path.relpath(source_dir, target_dir)
    processed_paths = []

    for path_name in path_names:
        # Remove any existing workspace folder reference
        clean_path = path_name.replace("${workspaceFolder}/", "")
        processed_path = f'"${{workspaceFolder}}/{rel_path}/{clean_path}"'
        processed_paths.append(processed_path)

    return processed_paths


def get_extra_paths_from_file(vscode_filename: str, source_dir: str, target_dir: str = None) -> list[str]:
    """Get extra paths from a VSCode settings file.

    Args:
        vscode_filename: Path to the VSCode settings file.
        source_dir: The source directory (relative to which paths are currently defined).
        target_dir: The target directory (relative to which paths should be defined).

    Returns:
        List of processed path names.
    """
    if not os.path.exists(vscode_filename):
        raise FileNotFoundError(f"Could not find the VS Code settings file: {vscode_filename}")

    vscode_settings = read_vscode_settings(vscode_filename)
    path_names = extract_extra_paths(vscode_settings)
    return process_path_names(path_names, source_dir, target_dir)


def overwrite_python_analysis_extra_paths(isaacsim_dir: str | None, vscode_settings: str) -> str:
    """Overwrite the extraPaths in the VS Code settings file.

    The extraPaths are replaced with the path names from the isaac-sim settings file that exists in the
    "{ISAACSIM_DIR}/.vscode/settings.json" file.

    If the isaac-sim VS Code settings file does not exist, the extraPaths are not overwritten.

    Args:
        isaacsim_dir: The path to the Isaac Sim directory.
        vscode_settings: The settings string to use as template.

    Returns:
        The settings string with overwritten python analysis extra paths.
    """
    # Get paths from Isaac Sim settings (if available)
    if isaacsim_dir is not None:
        isaacsim_vscode_filename = os.path.join(isaacsim_dir, ".vscode", "settings.json")
        isaacsim_paths = get_extra_paths_from_file(isaacsim_vscode_filename, isaacsim_dir)
    else:
        isaacsim_paths = []

    # Extract paths that were already in the template file
    template_paths = extract_extra_paths(vscode_settings)
    template_paths = process_path_names(template_paths, PROJECT_DIR)

    # combine them into a single string
    all_paths = isaacsim_paths + template_paths
    path_names = ",\n\t\t".expandtabs(4).join(all_paths)
    # deal with the path separator being different on Windows and Unix
    path_names = path_names.replace("\\", "/")

    for extra_path_type in ["python.analysis.extraPaths", "cursorpyright.analysis.extraPaths"]:
        # replace the path names in the VS Code settings file with the path names parsed
        vscode_settings = re.sub(
            rf"\"{extra_path_type}\": \[.*?\]",
            f'"{extra_path_type}": [\n\t\t'.expandtabs(4) + path_names + "\n\t]".expandtabs(4),
            vscode_settings,
            flags=re.DOTALL,
        )
    # return the VS Code settings string with modified extra paths
    return vscode_settings


def overwrite_default_python_interpreter(vscode_settings: str) -> str:
    """Overwrite the default python interpreter in the VS Code settings file.

    The default python interpreter is replaced with the path to the python interpreter used by the
    isaac-sim project. This is necessary because the default python interpreter is the one shipped with
    isaac-sim.

    Args:
        vscode_settings: The settings string to use as template.

    Returns:
        The settings string with overwritten default python interpreter.
    """
    # read executable name
    python_exe = os.path.normpath(sys.executable)

    # replace with Isaac Sim's python.sh or python.bat scripts to make sure python with correct
    # source paths is set as default
    if f"kit{os.sep}python{os.sep}bin{os.sep}python" in python_exe:
        # Check if the OS is Windows or Linux to use appropriate shell file
        if platform.system() == "Windows":
            python_exe = python_exe.replace(f"kit{os.sep}python{os.sep}bin{os.sep}python3", "python.bat")
        else:
            python_exe = python_exe.replace(f"kit{os.sep}python{os.sep}bin{os.sep}python3", "python.sh")

    # replace the default python interpreter in the VS Code settings file with the path to the
    # python interpreter in the Isaac Sim directory
    vscode_settings = re.sub(
        r"\"python.defaultInterpreterPath\": \".*?\"",
        f'"python.defaultInterpreterPath": "{python_exe}"',
        vscode_settings,
        flags=re.DOTALL,
    )
    # return the VS Code settings file with modified default python interpreter
    return vscode_settings


def create_header_message(template_filename: str) -> str:
    """Create a header message for generated files.

    Args:
        template_filename: The template filename to reference in the header.

    Returns:
        The header message string.
    """
    return (
        "// This file is a template and is automatically generated by the setup_vscode.py script.\n"
        "// Do not edit this file directly.\n"
        "// \n"
        f"// Generated from: {template_filename}\n"
    )


def write_settings_file(output_filename: str, content: str, template_filename: str):
    """Write settings content to a file with header.

    Args:
        output_filename: The output filename.
        content: The content to write.
        template_filename: The template filename for the header.
    """
    header_message = create_header_message(template_filename)
    full_content = header_message + content

    with open(output_filename, "w") as f:
        f.write(full_content)


def main():
    """Main function to setup the VS Code settings for the project."""
    # get the Isaac Sim directory
    isaacsim_dir = get_isaacsim_dir()

    # VS Code template settings
    pairlab_vscode_template_filename = os.path.join(PROJECT_DIR, ".vscode", "tools", "settings.template.json")

    # make sure the VS Code template settings file exists
    if not os.path.exists(pairlab_vscode_template_filename):
        raise FileNotFoundError(
            f"Could not find the PAIR Lab template settings file: {pairlab_vscode_template_filename}"
        )
    # read the Pair Lab VS Code template settings file
    with open(pairlab_vscode_template_filename) as f:
        pairlab_template_vscode_settings = f.read()

    # overwrite the extraPaths in the Isaac Sim settings file with the path names
    vscode_settings = overwrite_python_analysis_extra_paths(isaacsim_dir, pairlab_template_vscode_settings)
    vscode_settings = overwrite_default_python_interpreter(vscode_settings)

    # write the VS Code settings file
    isaaclab_vscode_filename = os.path.join(PROJECT_DIR, ".vscode", "settings.json")
    write_settings_file(isaaclab_vscode_filename, vscode_settings, pairlab_vscode_template_filename)

    # copy the launch.json file if it doesn't exist
    isaaclab_vscode_launch_filename = os.path.join(PROJECT_DIR, ".vscode", "launch.json")
    isaaclab_vscode_template_launch_filename = os.path.join(PROJECT_DIR, ".vscode", "tools", "launch.template.json")
    if not os.path.exists(isaaclab_vscode_launch_filename):
        # read template launch settings
        with open(isaaclab_vscode_template_launch_filename) as f:
            isaaclab_template_launch_settings = f.read()
        # write the VS Code launch settings file
        write_settings_file(
            isaaclab_vscode_launch_filename, isaaclab_template_launch_settings, isaaclab_vscode_template_launch_filename
        )


if __name__ == "__main__":
    main()