#! /bin/bash
# Copyright (C) 2026 Danilo M. <danix@danix.xyz>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License version 2 as published
# by the Free Software Foundation. See the LICENSE file for details.

# sbshadow: reconcile upstream shadowing against personal/ and pentesting/.
#
# Shadow: upstream package whose name matches a personal/pentesting package is
# git rm'd. Unshadow: upstream package no longer carried there is restored from
# the pristine $UPSTREAM branch that danix-current was cut from. Then regenerates
# phantom-dep hintfiles with mkhint -F.
#
# Called by slackrepo_setup_SBo-danix.sh and by sbpull after a subtree pull.
#
# Usage: sbshadow [--yes|--no]
#   no flag  show the plan and ask before changing anything
#   --yes    apply the plan without asking
#   --no     show the plan only, tree unchanged (preview)
# SBO_REPO overrides the repo path (used to test against a throwaway repo).

set -euo pipefail

answer=""
case "${1:-}" in
  --yes) answer=y ;;
  --no)  answer=n ;;
  "")    ;;
  *)     echo "usage: sbshadow [--yes|--no]" >&2; exit 2 ;;
esac

REPO="${SBO_REPO:-/var/lib/sbopkg/SBo-danix}"
UPSTREAM="current"

cd "$REPO"

# packages carried in the overlays
declare -A mine=()
for d in personal/*/ pentesting/*/; do
  p=$(basename "$d")
  [[ -f "$d$p.SlackBuild" ]] && mine[$p]=1
done

# category/pkg for every real package in pristine upstream
to_rm=() to_restore=()
while IFS= read -r path; do
  if [[ -n "${mine[${path#*/}]:-}" ]]; then
    [[ -d "$path" ]] && to_rm+=("$path")
  else
    [[ -d "$path" ]] || to_restore+=("$path")
  fi
done < <(git ls-tree -r --name-only "$UPSTREAM" \
           | grep -E '^[^/]+/([^/]+)/\1\.SlackBuild$' | xargs -r -n1 dirname)

if (( ${#to_rm[@]} + ${#to_restore[@]} == 0 )); then
  echo "sbshadow: nothing to shadow or unshadow."
else
  echo
  (( ${#to_rm[@]} ))      && printf 'shadow:   %s\n' "${to_rm[@]}"
  (( ${#to_restore[@]} )) && printf 'unshadow: %s\n' "${to_restore[@]}"
  echo

  if [[ -n $answer ]]; then
    confirm=$answer
  else
    read -rp "Proceed? [y/N] " confirm
  fi
  if [[ ! "$confirm" =~ ^[Yy]$ ]]; then
    echo "sbshadow: aborted, tree unchanged."
  else
    (( ${#to_rm[@]} ))      && git rm -rq -- "${to_rm[@]}"
    (( ${#to_restore[@]} )) && git checkout "$UPSTREAM" -- "${to_restore[@]}"
    git commit -qm "shadow: reconcile upstream against personal/pentesting"
    echo "sbshadow: shadowed ${#to_rm[@]}, unshadowed ${#to_restore[@]}."
  fi
fi

# ── regenerate phantom-dep hintfiles (mkhint owns them) ───────────────────────
# Runs even with nothing to shadow (a subtree pull can change REQUIRES), but
# not on --no: a preview leaves the hints alone too.
# mkhint reads ~/.config/mkhint/phantom-deps; missing tool = harmless skip.
if [[ $answer == n ]]; then
  echo
  echo "sbshadow: preview, phantom-dep hintfiles not regenerated."
elif command -v mkhint >/dev/null 2>&1; then
  echo
  echo "Regenerating phantom-dep hintfiles (mkhint -F)..."
  mkhint -F
else
  echo "NOTE: mkhint not found; skipping hintfile regen. Run 'mkhint -F' manually." >&2
fi