matrix: hive-matrix-mcp crate (daemon+stdio bridge) + harness wiring (#548 phase 3)

hive-matrix-mcp/src/paths.rs

@@ -0,0 +1,65 @@
+//! Per-agent filesystem paths used by both `hive-matrix-daemon` and the
+//! stdio MCP bridge.
+//!
+//! All paths are overridable via env vars for dev / test scenarios and
+//! to let the harness point the daemon at non-default locations when
+//! the operator overrides `hyperhive.matrix.*` options.
+
+use std::path::PathBuf;
+
+/// Default homeserver URL when `HIVE_MATRIX_URL` isn't set. Tuwunel
+/// (the local hive-matrix container) listens on `localhost:8008` by
+/// default; shared host netns means every agent container resolves
+/// `localhost` to the same machine.
+pub const DEFAULT_HOMESERVER: &str = "http://localhost:8008";
+
+/// Default unix socket path the daemon listens on inside the agent
+/// container. The stdio MCP bridge `connect()`s here on every tool call.
+/// `/run/hive-matrix.sock` is a tmpfs path that disappears on container
+/// restart — fine, because the daemon recreates the socket on its own
+/// boot.
+pub const DEFAULT_DAEMON_SOCKET: &str = "/run/hive-matrix.sock";
+
+/// Resolve the matrix access-token file path. Override via
+/// `HIVE_MATRIX_TOKEN_FILE`; default is `<HYPERHIVE_STATE_DIR>/matrix-token`,
+/// the path `hive-c0re::matrix::ensure_user_for` writes to on agent
+/// account provisioning.
+#[must_use]
+pub fn token_file() -> PathBuf {
+    if let Some(p) = std::env::var_os("HIVE_MATRIX_TOKEN_FILE") {
+        return PathBuf::from(p);
+    }
+    let state_dir = std::env::var("HYPERHIVE_STATE_DIR").unwrap_or_default();
+    PathBuf::from(format!("{state_dir}/matrix-token"))
+}
+
+/// Resolve the homeserver URL. Override via `HIVE_MATRIX_URL`; default
+/// is the in-container `localhost:8008` tuwunel.
+#[must_use]
+pub fn homeserver_url() -> String {
+    std::env::var("HIVE_MATRIX_URL").unwrap_or_else(|_| DEFAULT_HOMESERVER.to_owned())
+}
+
+/// Resolve the daemon's unix socket path. Override via
+/// `HIVE_MATRIX_SOCKET`; default is `/run/hive-matrix.sock`.
+#[must_use]
+pub fn daemon_socket() -> PathBuf {
+    std::env::var_os("HIVE_MATRIX_SOCKET").map_or_else(|| PathBuf::from(DEFAULT_DAEMON_SOCKET), PathBuf::from)
+}
+
+/// Persistent sqlite store directory for matrix-sdk's state (event
+/// cache, devices, etc.). Lives under the per-agent state dir so it
+/// survives container restart but gets wiped on `destroy --purge`.
+#[must_use]
+pub fn matrix_state_dir() -> PathBuf {
+    let state_dir = std::env::var("HYPERHIVE_STATE_DIR").unwrap_or_default();
+    PathBuf::from(format!("{state_dir}/matrix-sdk-state"))
+}
+
+/// Hyperhive control socket — the daemon writes wake signals here so
+/// the harness drives a new claude turn on incoming matrix events.
+/// Mirrors the path `forge_notify` writes to.
+#[must_use]
+pub fn hyperhive_socket() -> PathBuf {
+    std::env::var_os("HIVE_CONTROL_SOCKET").map_or_else(|| PathBuf::from("/run/hive/mcp.sock"), PathBuf::from)
+}