#!/bin/bash
# omarchy:summary=Install or remove the OmarchyCN layer on an existing Omarchy
# omarchy:args=[--uninstall]
# omarchy:examples=omarchy-cn-install-overlay | omarchy-cn-install-overlay --uninstall
# Bootstraps onto a foreign OMARCHY_PATH, so it resolves its own checkout root.

set -euo pipefail

SRC=$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")/.." && pwd)
DEST="${OMARCHY_PATH:?OMARCHY_PATH must point at the target Omarchy install}"
MANIFEST="$HOME/.local/state/omarchycn/overlay-manifest"

run_in() {
  local root="$1"
  shift
  if [[ -w $root ]]; then
    "$@"
  else
    sudo "$@"
  fi
}

valid_entry() {
  [[ $1 == "cn" || $1 =~ ^bin/(omarchycn|omarchy-cn-[a-z0-9-]+)$ ]]
}

uninstall() {
  if [[ ! -f $MANIFEST ]]; then
    echo "No overlay manifest at $MANIFEST" >&2
    exit 1
  fi

  local dest="" rel=""
  dest=$(grep -m1 '^dest=' "$MANIFEST" | cut -d= -f2-)
  if [[ -z $dest || ! -d $dest ]]; then
    echo "Manifest has no valid dest= record" >&2
    exit 1
  fi

  # Validate every entry before deleting anything
  while IFS= read -r rel; do
    [[ $rel == source=* || $rel == dest=* ]] && continue
    if ! valid_entry "$rel"; then
      echo "Refusing suspicious manifest entry: $rel (nothing deleted)" >&2
      exit 1
    fi
  done < "$MANIFEST"

  while IFS= read -r rel; do
    [[ $rel == source=* || $rel == dest=* ]] && continue
    if [[ $rel == "cn" ]]; then
      run_in "$dest" rm -rf "$dest/cn"
    else
      run_in "$dest" rm -f "$dest/$rel"
    fi
  done < "$MANIFEST"

  rm -f "$MANIFEST"
  echo "OmarchyCN overlay removed from $dest"
}

install() {
  if [[ ! -f $DEST/version || ! -x $DEST/bin/omarchy ]]; then
    echo "No Omarchy install found at $DEST" >&2
    exit 1
  fi
  if [[ $SRC == "$DEST" ]]; then
    echo "Source checkout and target are the same tree; nothing to overlay" >&2
    exit 1
  fi

  # Reinstall: remove the previous overlay first so upgrades leave no residue
  if [[ -f $MANIFEST ]]; then
    uninstall
  fi

  if [[ -e $DEST/cn ]]; then
    echo "Refusing to take over unmanaged $DEST/cn" >&2
    exit 1
  fi

  local f rel entries=()
  for f in "$SRC/bin/omarchycn" "$SRC"/bin/omarchy-cn-*; do
    rel="bin/${f##*/}"
    if [[ -e $DEST/$rel ]]; then
      echo "Refusing to overwrite unmanaged $DEST/$rel" >&2
      exit 1
    fi
    entries+=("$rel")
  done

  # Manifest is the intent record, published BEFORE copying: if a copy fails
  # midway, a rerun sees the manifest, uninstalls the partial state, retries.
  mkdir -p "${MANIFEST%/*}"
  {
    echo "source=$SRC"
    echo "dest=$DEST"
    echo "cn"
    printf '%s\n' "${entries[@]}"
  } > "$MANIFEST"

  run_in "$DEST" cp -r "$SRC/cn" "$DEST/cn"
  for rel in "${entries[@]}"; do
    run_in "$DEST" cp "$SRC/$rel" "$DEST/$rel"
  done

  echo "OmarchyCN overlay installed into $DEST (${#entries[@]} commands)"
  echo "Verify: omarchy cn version"
}

if [[ ${1:-} == "--uninstall" ]]; then
  uninstall
else
  install
fi