//! Shared in-container filesystem-path resolution.
//!
//! Every process that runs inside an agent container - the harness plus
//! the out-of-process MCP daemons (bash, matrix, ...) - must resolve the
//! harness directory layout identically. These helpers previously had to
//! be hand-mirrored across crates (each copy carrying a "keep in sync"
//! comment) because there was no shared home for them; they live here so
//! the resolution exists exactly once.

use std::path::PathBuf;

/// Base harness directory for the current agent. Uses `HYPERHIVE_HARNESS_DIR`
/// if set (injected by the hive-c0re meta flake after the harness/state
/// split); falls back to a `harness/` sibling of `HYPERHIVE_STATE_DIR` for
/// pre-split / dev deployments.
#[must_use]
pub fn harness_dir() -> PathBuf {
    if let Some(p) = std::env::var_os("HYPERHIVE_HARNESS_DIR") {
        return PathBuf::from(p);
    }
    let state = std::env::var("HYPERHIVE_STATE_DIR").unwrap_or_default();
    let state_path = PathBuf::from(&state);
    state_path
        .parent()
        .map_or_else(|| PathBuf::from(state), |p| p.join("harness"))
}

/// Directory where out-of-process MCP daemons write loose-end summary
/// files (`<name>.json`) for the harness to scan in `get_loose_ends`.
#[must_use]
pub fn mcp_loose_ends_dir() -> PathBuf {
    harness_dir().join("mcp-loose-ends")
}