"""Configuration and common utilities for Obsidian import."""

import os
from pathlib import Path
from typing import Optional

DEFAULT_CONFIG_PATH = Path.home() / ".config" / "obsidian-import" / "config.ini"


def get_vault_path(cli_vault: Optional[str] = None) -> Path:
    """Resolve the Obsidian vault path from CLI arg, env var, or default locations."""
    if cli_vault:
        vault = Path(cli_vault).expanduser().resolve()
        if not vault.exists():
            raise FileNotFoundError(f"Vault path does not exist: {vault}")
        return vault

    env_vault = os.environ.get("OBSIDIAN_VAULT")
    if env_vault:
        vault = Path(env_vault).expanduser().resolve()
        if vault.exists():
            return vault

    # Try common default locations
    obsidian_dir = Path.home() / "Obsidian"
    if obsidian_dir.exists():
        vaults = [d for d in obsidian_dir.iterdir() if d.is_dir()]
        if len(vaults) == 1:
            return vaults[0]
        elif len(vaults) > 1:
            raise RuntimeError(
                f"Multiple vaults found in {obsidian_dir}. "
                "Set OBSIDIAN_VAULT or use --vault."
            )

    raise RuntimeError(
        "Could not determine Obsidian vault path. "
        "Use --vault or set OBSIDIAN_VAULT environment variable."
    )


def sanitize_filename(name: str) -> str:
    """Remove or replace characters unsafe for filenames."""
    invalid = '<>:"/\\|?*'
    for ch in invalid:
        name = name.replace(ch, "_")
    return name.strip(". ")


def ensure_unique_path(target: Path) -> Path:
    """If target exists, append a counter to make it unique."""
    if not target.exists():
        return target
    stem = target.stem
    suffix = target.suffix
    parent = target.parent
    counter = 1
    while True:
        new_name = f"{stem}_{counter}{suffix}"
        candidate = parent / new_name
        if not candidate.exists():
            return candidate
        counter += 1