#!/usr/bin/env bash
# gstack-paths — output portable state-root paths for skill bash blocks
# Usage: eval "$(gstack-paths)"  → sets GSTACK_STATE_ROOT, PLAN_ROOT, TMP_ROOT
# Or:    gstack-paths            → prints GSTACK_STATE_ROOT=... etc.
#
# Resolves three roots with explicit fallback chains so skills work the same
# whether installed as a Claude Code plugin (CLAUDE_PLUGIN_DATA / CLAUDE_PLANS_DIR
# set), a global ~/.claude/skills/gstack/ install, or a local checkout under
# CI / container env where HOME may be unset.
#
# Chains:
#   GSTACK_STATE_ROOT: GSTACK_HOME -> CLAUDE_PLUGIN_DATA (only when CLAUDE_PLUGIN_ROOT=*gstack*) -> $HOME/.gstack -> .gstack
#   PLAN_ROOT:         GSTACK_PLAN_DIR -> CLAUDE_PLANS_DIR -> $HOME/.claude/plans -> .claude/plans
#   TMP_ROOT:          TMPDIR -> TMP -> .gstack/tmp (and mkdir -p, best-effort)
#
# Output: values are emitted shell-quoted (printf %q) so `eval` round-trips them
# byte-for-byte. This matters on Windows, where $TMP is a backslash path like
# C:\Users\me\AppData\Local\Temp — with a bare `echo`, eval consumes the
# backslashes as escapes and the caller gets C:UsersmeAppDataLocalTemp. A value
# containing a space (C:\Program Files\Temp) is worse: eval word-splits it and
# the variable ends up empty. Quoting here is the only fix that works, because
# the corruption happens during eval, before the caller has anything to quote.
# Callers should still quote expansions ("$GSTACK_STATE_ROOT") for the same
# reason any path variable needs quoting.
set -u

# State root: where gstack writes projects/, sessions/, analytics/.
if [ -n "${GSTACK_HOME:-}" ]; then
  _state_root="$GSTACK_HOME"
elif [ -n "${CLAUDE_PLUGIN_DATA:-}" ] && echo "${CLAUDE_PLUGIN_ROOT:-}" | grep -qi "gstack"; then
  # Guard: only trust CLAUDE_PLUGIN_DATA when CLAUDE_PLUGIN_ROOT confirms we are
  # running as the gstack plugin. Without this, a CLAUDE_PLUGIN_DATA from another
  # plugin (e.g. codex) that leaked into the session env via CLAUDE_ENV_FILE would
  # be picked up, writing all gstack state into the wrong directory.
  _state_root="$CLAUDE_PLUGIN_DATA"
elif [ -n "${HOME:-}" ]; then
  _state_root="$HOME/.gstack"
else
  _state_root=".gstack"
fi

# Plan root: where /context-save and /codex consult write plan files.
if [ -n "${GSTACK_PLAN_DIR:-}" ]; then
  _plan_root="$GSTACK_PLAN_DIR"
elif [ -n "${CLAUDE_PLANS_DIR:-}" ]; then
  _plan_root="$CLAUDE_PLANS_DIR"
elif [ -n "${HOME:-}" ]; then
  _plan_root="$HOME/.claude/plans"
else
  _plan_root=".claude/plans"
fi

# Tmp root: where ephemeral files (codex stderr captures, etc.) live.
# Honor TMPDIR / TMP for Windows + container compat; fall back to a
# project-local .gstack/tmp so we never write to a system /tmp that may
# be read-only or shared.
if [ -n "${TMPDIR:-}" ]; then
  _tmp_root="$TMPDIR"
elif [ -n "${TMP:-}" ]; then
  _tmp_root="$TMP"
else
  _tmp_root=".gstack/tmp"
fi
# macOS exports TMPDIR with a trailing slash; mktemp templates built as
# "$TMP_ROOT/name-XXXXXX" would then carry "//", and any consumer comparing
# paths gets a spurious mismatch. Strip it (never strips a bare "/"). #2091
case "$_tmp_root" in
  */) [ "$_tmp_root" != "/" ] && _tmp_root="${_tmp_root%/}" ;;
esac

# Strip any trailing slash so consumers can safely concatenate "$TMP_ROOT/name"
# without producing a double slash. On macOS $TMPDIR ends in `/` by default
# (e.g. /var/folders/.../T/), which would otherwise yield paths like
# `…/T//codex-err-…`. Normalizing at the source means every consumer benefits,
# not just /codex.
_tmp_root="${_tmp_root%/}"
# A value of "/" collapses to "" above; restore it so TMP_ROOT is never empty.
[ -z "$_tmp_root" ] && _tmp_root="/"

# Best-effort mkdir; if it fails (read-only fs, permission denied), the caller
# will discover that on their own write attempt. Don't fail the eval here.
mkdir -p "$_tmp_root" 2>/dev/null || true

printf 'GSTACK_STATE_ROOT=%q\n' "$_state_root"
printf 'PLAN_ROOT=%q\n' "$_plan_root"
printf 'TMP_ROOT=%q\n' "$_tmp_root"
