#!/usr/bin/env bash
# gstack-ceo-plan-find — print the CEO plan a plan review should read.
#
# Usage: gstack-ceo-plan-find <slug> <branch>
#
# Prints one absolute path, or nothing when no CEO plan exists. Exit 0 either
# way; exit 2 on a usage error. A plan from another branch (precedence 2) is
# disclosed on stderr: "CEO plan found (from branch <b>, not <branch>): <path>".
#
# /plan-ceo-review saves each plan as
# $GSTACK_STATE_ROOT/projects/<slug>/ceo-plans/<YYYY-MM-DD>-<feature>.md with a
# "Branch: <branch> | Mode: ..." header line. Precedence:
#   1. newest plan whose Branch line names <branch>, compared the way
#      gstack-slug writes BRANCH ("/" becomes "-")
#   2. else the newest plan, disclosed on stderr
# Only top-level ceo-plans/*.md counts: the same set /design-html and
# /plan-ceo-review's prior-plans query read.
set -u

if [ "$#" -ne 2 ] || [ -z "$1" ]; then
  echo "usage: gstack-ceo-plan-find <slug> <branch>" >&2
  exit 2
fi
SLUG=$1
BRANCH=$2

eval "$("$(dirname "$0")/gstack-paths")"; : "${GSTACK_STATE_ROOT:?gstack-paths failed; reinstall with ./setup or /gstack-upgrade}"

plan_branch() {
  awk '/^Branch: /{ sub(/^Branch: /, ""); sub(/\|.*/, ""); print; exit }' "$1" | tr '/' '-' | tr -cd 'a-zA-Z0-9._-'
}

NEWEST=""
FOR_BRANCH=""
for plan in "$GSTACK_STATE_ROOT/projects/$SLUG/ceo-plans/"*.md; do
  [ -f "$plan" ] || continue
  if [ -z "$NEWEST" ] || [ "$plan" -nt "$NEWEST" ]; then NEWEST=$plan; fi
  if [ -n "$BRANCH" ] && [ "$(plan_branch "$plan")" = "$BRANCH" ]; then
    if [ -z "$FOR_BRANCH" ] || [ "$plan" -nt "$FOR_BRANCH" ]; then FOR_BRANCH=$plan; fi
  fi
done

PLAN=${FOR_BRANCH:-$NEWEST}
[ -n "$PLAN" ] || exit 0
if [ -z "$FOR_BRANCH" ]; then
  FROM=$(awk '/^Branch: /{ sub(/^Branch: /, ""); sub(/ *\|.*/, ""); print; exit }' "$PLAN" | LC_ALL=C tr -d '\000-\037\177')
  echo "CEO plan found (from branch ${FROM:-unknown}, not ${BRANCH:-unknown}): $PLAN" >&2
fi
printf '%s\n' "$PLAN"
exit 0