#!/usr/bin/env bash
# migrate-phases-to-tasks.sh — convert the flat phase-file layout to the
# phase-directory + task-file layout.
#
# Each numeric-prefixed flat phase file in {todo,complete}/ is wrapped into a
# directory of the same name with the file renamed to 00_phase.md:
#
#   todo/03_api.md          →  todo/03_api/00_phase.md
#   complete/01_init.md     →  complete/01_init/00_phase.md
#
# The harness still executes wrapped phases: their inline task lists are
# picked up by the phase's 00_phase.md final pass, so this is safe
# mid-pipeline. Splitting a wrapped todo phase into real task files is the
# phase-authoring skill's job, not this script's. Already-migrated phases are
# left alone; a flat file colliding with an existing same-name directory is
# reported and skipped.
#
# Usage: bash migrate-phases-to-tasks.sh [project-root]
#   project-root defaults to the nearest ancestor containing
#   .agent/phases/todo or agent/phases/todo (older projects).
set -euo pipefail

root="${1:-}"
if [[ -n "$root" ]]; then
  [[ -d "$root" ]] || { echo "✗ ERROR: $root is not a directory" >&2; exit 1; }
else
  root="$(pwd)"
  while :; do
    if [[ -d "$root/.agent/phases/todo" || -d "$root/agent/phases/todo" ]]; then break; fi
    [[ "$root" == "/" ]] && { echo "✗ ERROR: no phases/todo found at or above $(pwd)" >&2; exit 1; }
    root="$(dirname "$root")"
  done
fi

if [[ -d "$root/.agent/phases" ]]; then
  phases="$root/.agent/phases"
elif [[ -d "$root/agent/phases" ]]; then
  phases="$root/agent/phases"
else
  echo "✗ ERROR: no phases directory under $root" >&2
  exit 1
fi

echo "project root: $root"
echo "phases:       $phases"
echo

moved=0 skipped=0
for d in todo complete; do
  [[ -d "$phases/$d" ]] || continue
  for f in "$phases/$d"/*.md; do
    [[ -e "$f" ]] || continue
    base="$(basename "$f" .md)"
    [[ "$base" =~ ^[0-9] ]] || continue
    if [[ -d "$phases/$d/$base" ]]; then
      echo "⚠ skip: $d/$base.md — directory $d/$base/ already exists (conflict)" >&2
      skipped=$((skipped + 1))
      continue
    fi
    mkdir -p "$phases/$d/$base"
    mv -f "$f" "$phases/$d/$base/00_phase.md"
    echo "  $d/$base.md → $d/$base/00_phase.md"
    moved=$((moved + 1))
  done
done

echo
echo "migrated: $moved phase file(s) → 00_phase.md directory layout; skipped: $skipped"
if (( moved > 0 )); then
  echo "wrapped todo phases now run as a single final pass; use the phase-authoring"
  echo "skill to split their inline task lists into real task files."
fi