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"""
Core shared utilities for the Nymbo-Tools MCP server.

Consolidates three key areas:
1. Sandboxed filesystem operations (path resolution, reading, writing, safe_open)
2. Sandboxed Python execution (code interpreter, agent terminal)
3. Hugging Face inference utilities (token, providers, error handling)
"""

from __future__ import annotations

import ast
import json
import os
import re
import stat
import sys
from datetime import datetime
from io import StringIO
from typing import Any, Callable, Optional, TypeVar

import gradio as gr


# ===========================================================================
# Part 0: Tree Rendering Utilities
# ===========================================================================


def _fmt_size(num_bytes: int) -> str:
    """Format byte size as human-readable string."""
    units = ["B", "KB", "MB", "GB"]
    size = float(num_bytes)
    for unit in units:
        if size < 1024.0:
            return f"{size:.1f} {unit}"
        size /= 1024.0
    return f"{size:.1f} TB"


def build_tree(entries: list[tuple[str, dict]]) -> dict:
    """
    Build a nested tree structure from flat path entries.
    
    Args:
        entries: List of (path, metadata) tuples where path uses forward slashes.
                 Paths ending with '/' are treated as directories.
    
    Returns:
        Nested dict with "__files__" key for files at each level.
    """
    root: dict = {"__files__": []}
    
    for path, metadata in entries:
        parts = path.rstrip("/").split("/")
        is_dir = path.endswith("/")
        
        node = root
        for i, part in enumerate(parts[:-1]):
            if part not in node:
                node[part] = {"__files__": []}
            node = node[part]
        
        final = parts[-1]
        if is_dir:
            if final not in node:
                node[final] = {"__files__": []}
            if metadata:
                node[final]["__meta__"] = metadata
        else:
            node["__files__"].append((final, metadata))
    
    return root


def render_tree(
    node: dict,
    prefix: str = "",
    format_entry: Optional[Callable[[str, dict, bool], str]] = None,
) -> list[str]:
    """
    Render a tree with line connectors.
    
    Args:
        node: Nested dict from build_tree()
        prefix: Current line prefix for indentation
        format_entry: Optional callback to format each entry.
    
    Returns:
        List of formatted lines.
    """
    result = []
    
    def default_format(name: str, meta: dict, is_dir: bool) -> str:
        if is_dir:
            return f"{name}/"
        size = meta.get("size")
        if size is not None:
            return f"{name}  ({_fmt_size(size)})"
        return name
    
    fmt = format_entry or default_format
    
    entries = []
    subdirs = sorted(k for k in node.keys() if k not in ("__files__", "__meta__"))
    files_here = sorted(node.get("__files__", []), key=lambda x: x[0])
    
    for dirname in subdirs:
        dir_meta = node[dirname].get("__meta__", {})
        entries.append(("dir", dirname, node[dirname], dir_meta))
    for fname, fmeta in files_here:
        entries.append(("file", fname, None, fmeta))
    
    for i, entry in enumerate(entries):
        is_last = (i == len(entries) - 1)
        connector = "└── " if is_last else "├── "
        child_prefix = prefix + ("    " if is_last else "│   ")
        
        etype, name, subtree, meta = entry
        
        if etype == "dir":
            result.append(f"{prefix}{connector}{fmt(name, meta, True)}")
            result.extend(render_tree(subtree, child_prefix, format_entry))
        else:
            result.append(f"{prefix}{connector}{fmt(name, meta, False)}")
    
    return result


def walk_and_build_tree(
    abs_path: str,
    *,
    show_hidden: bool = False,
    recursive: bool = False,
    max_entries: int = 100,
) -> tuple[dict, int, bool]:
    """
    Walk a directory and build a tree structure.
    
    Returns:
        (tree, total_entries, truncated)
    """
    entries: list[tuple[str, dict]] = []
    total = 0
    truncated = False
    
    for root, dirs, files in os.walk(abs_path):
        if not show_hidden:
            dirs[:] = [d for d in dirs if not d.startswith('.')]
            files = [f for f in files if not f.startswith('.')]
        
        dirs.sort()
        files.sort()
        
        try:
            rel_root = os.path.relpath(root, abs_path)
        except Exception:
            rel_root = ""
        prefix = "" if rel_root == "." else rel_root.replace("\\", "/") + "/"
        
        for d in dirs:
            p = os.path.join(root, d)
            try:
                mtime = datetime.fromtimestamp(os.path.getmtime(p)).strftime("%Y-%m-%d %H:%M")
            except Exception:
                mtime = "?"
            entries.append((f"{prefix}{d}/", {"mtime": mtime}))
            total += 1
            if total >= max_entries:
                truncated = True
                break
        
        if truncated:
            break
        
        for f in files:
            p = os.path.join(root, f)
            try:
                size = os.path.getsize(p)
                mtime = datetime.fromtimestamp(os.path.getmtime(p)).strftime("%Y-%m-%d %H:%M")
            except Exception:
                size, mtime = 0, "?"
            entries.append((f"{prefix}{f}", {"size": size, "mtime": mtime}))
            total += 1
            if total >= max_entries:
                truncated = True
                break
        
        if truncated:
            break
        
        if not recursive:
            break
    
    return build_tree(entries), total, truncated


def format_dir_listing(
    abs_path: str,
    display_path: str,
    *,
    show_hidden: bool = False,
    recursive: bool = False,
    max_entries: int = 100,
    fmt_size_fn: Optional[Callable[[int], str]] = None,
) -> str:
    """Format a directory listing as a visual tree."""
    fmt_size = fmt_size_fn or _fmt_size
    
    tree, total, truncated = walk_and_build_tree(
        abs_path,
        show_hidden=show_hidden,
        recursive=recursive,
        max_entries=max_entries,
    )
    
    def format_entry(name: str, meta: dict, is_dir: bool) -> str:
        mtime = meta.get("mtime", "")
        if is_dir:
            return f"{name}/  ({mtime})"
        size = meta.get("size", 0)
        return f"{name}  ({fmt_size(size)}, {mtime})"
    
    tree_lines = render_tree(tree, "    ", format_entry)
    
    header = f"Listing of {display_path}\nRoot: /\nEntries: {total}"
    if truncated:
        header += f"\n… Truncated at {max_entries} entries."
    
    lines = [header, "", "└── /"]
    lines.extend(tree_lines)
    
    return "\n".join(lines).strip()


# ===========================================================================
# Part 1: Sandboxed Filesystem Operations
# ===========================================================================


class SandboxedRoot:
    """
    A configurable sandboxed root directory with path resolution and safety checks.
    
    Args:
        root_dir: Absolute path to the sandbox root.
        allow_abs: If True, allow absolute paths outside the sandbox.
    """
    
    def __init__(self, root_dir: str, allow_abs: bool = False):
        self.root_dir = os.path.abspath(root_dir)
        self.allow_abs = allow_abs
        # Ensure root exists
        try:
            os.makedirs(self.root_dir, exist_ok=True)
        except Exception:
            pass
    
    def safe_err(self, exc: Exception | str) -> str:
        """Return an error string with any absolute root replaced by '/' and slashes normalized."""
        s = str(exc)
        s_norm = s.replace("\\", "/")
        root_fwd = self.root_dir.replace("\\", "/")
        root_variants = {self.root_dir, root_fwd, re.sub(r"/+", "/", root_fwd)}
        for variant in root_variants:
            if variant:
                s_norm = s_norm.replace(variant, "/")
        s_norm = re.sub(r"/+", "/", s_norm)
        return s_norm

    def err(
        self,
        code: str,
        message: str,
        *,
        path: Optional[str] = None,
        hint: Optional[str] = None,
        data: Optional[dict] = None,
    ) -> str:
        """Return a structured error JSON string."""
        payload = {
            "status": "error",
            "code": code,
            "message": message,
            "root": "/",
        }
        if path is not None and path != "":
            payload["path"] = path
        if hint:
            payload["hint"] = hint
        if data:
            payload["data"] = data
        return json.dumps(payload, ensure_ascii=False)

    def display_path(self, abs_path: str) -> str:
        """Return a user-friendly path relative to root using forward slashes."""
        try:
            norm_root = os.path.normpath(self.root_dir)
            norm_abs = os.path.normpath(abs_path)
            common = os.path.commonpath([norm_root, norm_abs])
            if os.path.normcase(common) == os.path.normcase(norm_root):
                rel = os.path.relpath(norm_abs, norm_root)
                if rel == ".":
                    return "/"
                return "/" + rel.replace("\\", "/")
        except Exception:
            pass
        return abs_path.replace("\\", "/")

    def resolve_path(self, path: str) -> tuple[str, str]:
        """
        Resolve a user-provided path to an absolute, normalized path constrained to root.
        Returns (abs_path, error_message). error_message is empty when ok.
        """
        try:
            user_input = (path or "/").strip() or "/"
            if user_input.startswith("/"):
                rel_part = user_input.lstrip("/") or "."
                raw = os.path.expanduser(rel_part)
                treat_as_relative = True
            else:
                raw = os.path.expanduser(user_input)
                treat_as_relative = False

            if not treat_as_relative and os.path.isabs(raw):
                if not self.allow_abs:
                    return "", self.err(
                        "absolute_path_disabled",
                        "Absolute paths are disabled in safe mode.",
                        path=raw.replace("\\", "/"),
                        hint="Use a path relative to / (e.g., /notes/todo.txt).",
                    )
                abs_path = os.path.abspath(raw)
            else:
                abs_path = os.path.abspath(os.path.join(self.root_dir, raw))
            
            # Constrain to root when not allowing absolute paths
            if not self.allow_abs:
                try:
                    common = os.path.commonpath(
                        [os.path.normpath(self.root_dir), os.path.normpath(abs_path)]
                    )
                    if common != os.path.normpath(self.root_dir):
                        return "", self.err(
                            "path_outside_root",
                            "Path is outside the sandbox root.",
                            path=abs_path,
                        )
                except Exception:
                    return "", self.err(
                        "path_outside_root",
                        "Path is outside the sandbox root.",
                        path=abs_path,
                    )

            return abs_path, ""
        except Exception as exc:
            return "", self.err(
                "resolve_path_failed",
                "Failed to resolve path.",
                path=(path or ""),
                data={"error": self.safe_err(exc)},
            )

    def safe_open(self, file, *args, **kwargs):
        """A drop-in replacement for open() that enforces sandbox constraints."""
        if isinstance(file, int):
            return open(file, *args, **kwargs)
        
        path_str = os.fspath(file)
        abs_path, err = self.resolve_path(path_str)
        if err:
            try:
                msg = json.loads(err)["message"]
            except Exception:
                msg = err
            raise PermissionError(f"Sandboxed open() failed: {msg}")
        
        return open(abs_path, *args, **kwargs)

    def list_dir(
        self,
        abs_path: str,
        *,
        show_hidden: bool = False,
        recursive: bool = False,
        max_entries: int = 100,
    ) -> str:
        """List directory contents as a visual tree."""
        return format_dir_listing(
            abs_path,
            self.display_path(abs_path),
            show_hidden=show_hidden,
            recursive=recursive,
            max_entries=max_entries,
            fmt_size_fn=_fmt_size,
        )

    def search_text(
        self,
        abs_path: str,
        query: str,
        *,
        recursive: bool = False,
        show_hidden: bool = False,
        max_results: int = 20,
        case_sensitive: bool = False,
        start_index: int = 0,
    ) -> str:
        """Search for text within files."""
        if not os.path.exists(abs_path):
            return self.err(
                "path_not_found",
                f"Path not found: {self.display_path(abs_path)}",
                path=self.display_path(abs_path),
            )

        query = query or ""
        normalized_query = query if case_sensitive else query.lower()
        if normalized_query == "":
            return self.err(
                "missing_search_query",
                "Search query is required for the search action.",
                hint="Provide text in the Content field to search for.",
            )

        max_results = max(1, int(max_results) if max_results is not None else 20)
        start_index = max(0, int(start_index) if start_index is not None else 0)
        matches: list[tuple[str, int, str]] = []
        errors: list[str] = []
        files_scanned = 0
        truncated = False
        total_matches = 0

        def _should_skip(name: str) -> bool:
            return not show_hidden and name.startswith(".")

        def _handle_match(file_path: str, line_no: int, line_text: str) -> bool:
            nonlocal truncated, total_matches
            total_matches += 1
            if total_matches <= start_index:
                return False
            if len(matches) < max_results:
                snippet = line_text.strip()
                if len(snippet) > 200:
                    snippet = snippet[:197] + "…"
                matches.append((self.display_path(file_path), line_no, snippet))
                return False
            truncated = True
            return True

        def _search_file(file_path: str) -> bool:
            nonlocal files_scanned
            files_scanned += 1
            try:
                with open(file_path, "r", encoding="utf-8", errors="replace") as handle:
                    for line_no, line in enumerate(handle, start=1):
                        haystack = line if case_sensitive else line.lower()
                        if normalized_query in haystack:
                            if _handle_match(file_path, line_no, line):
                                return True
            except Exception as exc:
                errors.append(f"{self.display_path(file_path)} ({self.safe_err(exc)})")
            return truncated

        if os.path.isfile(abs_path):
            _search_file(abs_path)
        else:
            for root, dirs, files in os.walk(abs_path):
                dirs[:] = [d for d in dirs if not _should_skip(d)]
                visible_files = [f for f in files if show_hidden or not f.startswith(".")]
                for name in visible_files:
                    file_path = os.path.join(root, name)
                    if _search_file(file_path):
                        break
                if truncated:
                    break
                if not recursive:
                    break

        header_lines = [
            f"Search results for {query!r}",
            f"Scope: {self.display_path(abs_path)}",
            f"Recursive: {'yes' if recursive else 'no'}, Hidden: {'yes' if show_hidden else 'no'}, Case-sensitive: {'yes' if case_sensitive else 'no'}",
            f"Start offset: {start_index}",
            f"Matches returned: {len(matches)}" + (" (truncated)" if truncated else ""),
            f"Files scanned: {files_scanned}",
        ]

        next_cursor = start_index + len(matches) if truncated else None

        if truncated:
            header_lines.append(f"Matches encountered before truncation: {total_matches}")
            header_lines.append(f"Truncated: yes — re-run with offset={next_cursor} to continue.")
            header_lines.append(f"Next cursor: {next_cursor}")
        else:
            header_lines.append(f"Total matches found: {total_matches}")
            header_lines.append("Truncated: no — end of results.")
            header_lines.append("Next cursor: None")

        if not matches:
            if total_matches > 0 and start_index >= total_matches:
                hint_limit = max(total_matches - 1, 0)
                body_lines = [
                    f"No matches found at or after offset {start_index}. Total matches available: {total_matches}.",
                    (f"Try a smaller offset (≤ {hint_limit})." if hint_limit >= 0 else ""),
                ]
                body_lines = [line for line in body_lines if line]
            else:
                body_lines = [
                    "No matches found.",
                    (f"Total matches encountered: {total_matches}." if total_matches else ""),
                ]
                body_lines = [line for line in body_lines if line]
        else:
            body_lines = [
                f"{idx}. {path}:{line_no}: {text}"
                for idx, (path, line_no, text) in enumerate(matches, start=1)
            ]

        if errors:
            shown = errors[:5]
            body_lines.extend(["", "Warnings:"])
            body_lines.extend(shown)
            if len(errors) > len(shown):
                body_lines.append(f"… {len(errors) - len(shown)} additional files could not be read.")

        return "\n".join(header_lines) + "\n\n" + "\n".join(body_lines)

    def read_file(self, abs_path: str, *, offset: int = 0, max_chars: int = 4000) -> str:
        """Read file contents with optional offset and character limit."""
        if not os.path.exists(abs_path):
            return self.err(
                "file_not_found",
                f"File not found: {self.display_path(abs_path)}",
                path=self.display_path(abs_path),
            )
        if os.path.isdir(abs_path):
            return self.err(
                "is_directory",
                f"Path is a directory, not a file: {self.display_path(abs_path)}",
                path=self.display_path(abs_path),
                hint="Provide a file path.",
            )
        try:
            with open(abs_path, "r", encoding="utf-8", errors="replace") as f:
                data = f.read()
        except Exception as exc:
            return self.err(
                "read_failed",
                "Failed to read file.",
                path=self.display_path(abs_path),
                data={"error": self.safe_err(exc)},
            )
        total = len(data)
        start = max(0, min(offset, total))
        if max_chars > 0:
            end = min(total, start + max_chars)
        else:
            end = total
        chunk = data[start:end]
        next_cursor = end if end < total else None
        header = (
            f"Reading {self.display_path(abs_path)}\n"
            f"Offset {start}, returned {len(chunk)} of {total}."
            + (f"\nNext cursor: {next_cursor}" if next_cursor is not None else "")
        )
        sep = "\n\n---\n\n"
        return header + sep + chunk

    def info(self, abs_path: str) -> str:
        """Get file/directory metadata as JSON."""
        try:
            st = os.stat(abs_path)
        except Exception as exc:
            return self.err(
                "stat_failed",
                "Failed to stat path.",
                path=self.display_path(abs_path),
                data={"error": self.safe_err(exc)},
            )
        info_dict = {
            "path": self.display_path(abs_path),
            "type": "directory" if stat.S_ISDIR(st.st_mode) else "file",
            "size": st.st_size,
            "modified": datetime.fromtimestamp(st.st_mtime).isoformat(sep=" ", timespec="seconds"),
            "created": datetime.fromtimestamp(st.st_ctime).isoformat(sep=" ", timespec="seconds"),
            "mode": oct(st.st_mode),
            "root": "/",
        }
        return json.dumps(info_dict, indent=2)


# ---------------------------------------------------------------------------
# Default roots (can be overridden by environment variables)
# ---------------------------------------------------------------------------

def _get_filesystem_root() -> str:
    """Get the default filesystem root directory."""
    root = os.getenv("NYMBO_TOOLS_ROOT")
    if root and root.strip():
        return os.path.abspath(os.path.expanduser(root.strip()))
    try:
        here = os.path.abspath(__file__)
        tools_dir = os.path.dirname(os.path.dirname(here))
        return os.path.abspath(os.path.join(tools_dir, "Filesystem"))
    except Exception:
        return os.path.abspath(os.getcwd())


def _get_obsidian_root() -> str:
    """Get the default Obsidian vault root directory."""
    env_root = os.getenv("OBSIDIAN_VAULT_ROOT")
    if env_root and env_root.strip():
        return os.path.abspath(os.path.expanduser(env_root.strip()))
    try:
        here = os.path.abspath(__file__)
        tools_dir = os.path.dirname(os.path.dirname(here))
        return os.path.abspath(os.path.join(tools_dir, "Obsidian"))
    except Exception:
        return os.path.abspath(os.getcwd())


# Pre-configured sandbox instances
ALLOW_ABS = bool(int(os.getenv("UNSAFE_ALLOW_ABS_PATHS", "0")))

FILESYSTEM_ROOT = _get_filesystem_root()
OBSIDIAN_ROOT = _get_obsidian_root()

# Default sandbox for /Filesystem (used by most tools)
filesystem_sandbox = SandboxedRoot(FILESYSTEM_ROOT, allow_abs=ALLOW_ABS)

# Sandbox for /Obsidian vault
obsidian_sandbox = SandboxedRoot(OBSIDIAN_ROOT, allow_abs=ALLOW_ABS)


# Convenience exports (for backward compatibility)
ROOT_DIR = FILESYSTEM_ROOT

def _resolve_path(path: str) -> tuple[str, str]:
    """Resolve path using the default filesystem sandbox."""
    return filesystem_sandbox.resolve_path(path)

def _display_path(abs_path: str) -> str:
    """Display path using the default filesystem sandbox."""
    return filesystem_sandbox.display_path(abs_path)

def safe_open(file, *args, **kwargs):
    """Open file using the default filesystem sandbox."""
    return filesystem_sandbox.safe_open(file, *args, **kwargs)


# ===========================================================================
# Part 2: Sandboxed Python Execution
# ===========================================================================


def create_safe_builtins() -> dict:
    """Create a builtins dict with sandboxed open()."""
    if isinstance(__builtins__, dict):
        safe_builtins = __builtins__.copy()
    else:
        safe_builtins = vars(__builtins__).copy()
    safe_builtins["open"] = safe_open
    return safe_builtins


def sandboxed_exec(
    code: str,
    *,
    extra_globals: dict[str, Any] | None = None,
    ast_mode: bool = False,
) -> str:
    """
    Execute Python code in a sandboxed environment.
    
    Args:
        code: Python source code to execute
        extra_globals: Additional globals to inject (e.g., tools)
        ast_mode: If True, parse and print results of all expression statements
                  (like Agent_Terminal). If False, simple exec (like Code_Interpreter).
    
    Returns:
        Captured stdout output, or exception text on error.
    """
    if not code:
        return "No code provided."
    
    old_stdout = sys.stdout
    old_cwd = os.getcwd()
    redirected_output = sys.stdout = StringIO()
    
    # Build execution environment
    safe_builtins = create_safe_builtins()
    env: dict[str, Any] = {
        "open": safe_open,
        "__builtins__": safe_builtins,
        "print": print,
    }
    if extra_globals:
        env.update(extra_globals)
    
    try:
        os.chdir(ROOT_DIR)
        
        if ast_mode:
            # Parse and evaluate each statement, printing expression results
            tree = ast.parse(code)
            for node in tree.body:
                if isinstance(node, ast.Expr):
                    # Standalone expression - evaluate and print result
                    expr = compile(ast.Expression(node.value), filename="<string>", mode="eval")
                    result_val = eval(expr, env)
                    if result_val is not None:
                        print(result_val)
                else:
                    # Statement - execute it
                    mod = ast.Module(body=[node], type_ignores=[])
                    exec(compile(mod, filename="<string>", mode="exec"), env)
        else:
            # Simple exec mode
            exec(code, env)
        
        result = redirected_output.getvalue()
    except Exception as exc:
        result = str(exc)
    finally:
        sys.stdout = old_stdout
        try:
            os.chdir(old_cwd)
        except Exception:
            pass
    
    return result


# ===========================================================================
# Part 3: Hugging Face Inference Utilities
# ===========================================================================


def get_hf_token() -> str | None:
    """Get the HF API token from environment variables.
    
    Checks HF_READ_TOKEN first, then falls back to HF_TOKEN.
    """
    return os.getenv("HF_READ_TOKEN") or os.getenv("HF_TOKEN")


# Pre-instantiated token for modules that prefer this pattern
HF_TOKEN = get_hf_token()

# Standard provider list for image/video generation
DEFAULT_PROVIDERS = ["auto", "replicate", "fal-ai"]

# Provider list for text generation (Deep Research)
TEXTGEN_PROVIDERS = ["cerebras", "auto"]


T = TypeVar("T")


def handle_hf_error(msg: str, model_id: str, *, context: str = "generation") -> None:
    """
    Raise appropriate gr.Error for common HF API error codes.
    
    Args:
        msg: Error message string to analyze
        model_id: The model ID being used (for error messages)
        context: Description of operation for error messages
    
    Raises:
        gr.Error: With user-friendly message based on error type
    """
    lowered = msg.lower()
    
    if "404" in msg:
        raise gr.Error(f"Model not found or unavailable: {model_id}. Check the id and your HF token access.")
    
    if "503" in msg:
        raise gr.Error("The model is warming up. Please try again shortly.")
    
    if "401" in msg or "403" in msg:
        raise gr.Error("Please duplicate the space and provide a `HF_READ_TOKEN` to enable Image and Video Generation.")
    
    if any(pattern in lowered for pattern in ("api_key", "hf auth login", "unauthorized", "forbidden")):
        raise gr.Error("Please duplicate the space and provide a `HF_READ_TOKEN` to enable Image and Video Generation.")
    
    # If none of the known patterns match, raise generic error
    raise gr.Error(f"{context.capitalize()} failed: {msg}")


def invoke_with_fallback(
    fn: Callable[[str], T],
    providers: list[str] | None = None,
) -> T:
    """
    Try calling fn(provider) for each provider until one succeeds.
    
    Args:
        fn: Function that takes a provider string and returns a result.
            Should raise an exception on failure.
        providers: List of provider strings to try. Defaults to DEFAULT_PROVIDERS.
    
    Returns:
        The result from the first successful fn() call.
    
    Raises:
        The last exception if all providers fail.
    """
    if providers is None:
        providers = DEFAULT_PROVIDERS
    
    last_error: Exception | None = None
    
    for provider in providers:
        try:
            return fn(provider)
        except Exception as exc:
            last_error = exc
            continue
    
    # All providers failed
    if last_error:
        raise last_error
    raise RuntimeError("No providers available")


# ===========================================================================
# Public API
# ===========================================================================

__all__ = [
    # Tree Utils
    "_fmt_size",
    "build_tree",
    "render_tree",
    "walk_and_build_tree",
    "format_dir_listing",
    # Filesystem
    "SandboxedRoot",
    "filesystem_sandbox",
    "obsidian_sandbox",
    "ROOT_DIR",
    "FILESYSTEM_ROOT",
    "OBSIDIAN_ROOT",
    "ALLOW_ABS",
    "_resolve_path",
    "_display_path",
    "safe_open",
    # Execution
    "sandboxed_exec",
    "create_safe_builtins",
    # HF Inference
    "get_hf_token",
    "HF_TOKEN",
    "DEFAULT_PROVIDERS",
    "TEXTGEN_PROVIDERS",
    "handle_hf_error",
    "invoke_with_fallback",
]