#!/usr/bin/env bash
# Resolve and ensure the working-tree directory SDD uses for one plan's
# short-lived artifacts: task briefs, implementer reports, review packages,
# and the progress ledger. Print the plan directory's absolute path.
#
# One directory per plan (.superpowers/sdd/<plan-basename>/) so a follow-up
# plan in the same working tree can never read or overwrite another plan's
# artifacts. A stale ledger misread as current progress makes controllers
# skip whole task sequences — plan-scoping removes that failure structurally.
#
# The workspace lives in the working tree (not under .git/) because Claude Code
# treats .git/ as a protected path and denies agent writes there — which blocks
# an implementer subagent from writing its report file. A self-ignoring
# .gitignore at .superpowers/sdd/ keeps every plan's workspace out of
# `git status` and out of accidental commits without modifying any tracked file.
#
# Single source of truth for the workspace location, so task-brief and
# review-package cannot drift to different directories.
#
# Usage: sdd-workspace PLAN_FILE
set -euo pipefail

if [ $# -ne 1 ]; then
  echo "usage: sdd-workspace PLAN_FILE" >&2
  exit 2
fi

plan=$1
[ -f "$plan" ] || { echo "no such plan file: $plan" >&2; exit 2; }

slug=$(basename "$plan" .md)
[ -n "$slug" ] && [ "$slug" != "." ] && [ "$slug" != ".." ] \
  || { echo "cannot derive a workspace name from: $plan" >&2; exit 2; }

root=$(git rev-parse --show-toplevel)
base="$root/.superpowers/sdd"
dir="$base/$slug"
mkdir -p "$dir"
printf '*\n' > "$base/.gitignore"
cd "$dir" && pwd
