#!/usr/bin/env bash
# Nightly AUR package reconciler.
#
#   usage: autoupdate.sh <package> [...]
#
#   env:
#     GIT_HOST       git host holding the package repos (default git.bjphoster.com)
#     WORKDIR        where to clone; a temp dir by default
#     NO_GIT_PUSH=1  do everything except push (dry run)
#     FORCE_REBUILD=1  bump pkgrel even with no detected change
#     FORCE_REFRESH=1  re-download remote sources even without a version change
#
# This is a RECONCILER, not a version-bump script. A new upstream release is
# only one of the things that can make a package diverge from the AUR; a manual
# push to origin is another, and a failed push last night is a third. All three
# funnel through the same path, and the AUR reconcile at the end runs
# unconditionally.

set -euo pipefail

_here="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=common.sh
source "${_here}/common.sh"

require_noninteractive
require_tools

GIT_HOST="${GIT_HOST:-git.bjphoster.com}"
# Where the package repos live, and how the upstream version is resolved.
# Both are overridable so the test suite can run hermetically against local
# bare repos; the defaults are the production values.
PKG_REPO_BASE="${PKG_REPO_BASE:-https://${GIT_HOST}/aur}"
LATEST_VERSION_CMD="${LATEST_VERSION_CMD:-${_here}/latest-version.sh}"

[ "$#" -ge 1 ] || die "usage: autoupdate.sh <package> [...]"

WORKDIR="${WORKDIR:-$(mktemp -d)}"
mkdir -p "$WORKDIR"

update_one() {
  local pkg="$1"
  local dir="${WORKDIR}/${pkg}"

  log "=== ${pkg} ==="

  if [ -d "$dir/.git" ]; then
    git -C "$dir" fetch --quiet origin
    git -C "$dir" reset --quiet --hard origin/HEAD
  else
    rm -rf "$dir"
    git clone --quiet "${PKG_REPO_BASE}/${pkg}" "$dir" \
      || die "could not clone ${pkg} from ${PKG_REPO_BASE}"
  fi

  cd "$dir"
  [ -f PKGBUILD ] || die "${pkg} has no PKGBUILD"
  [ -f .autoupdate ] || die "${pkg} has no .autoupdate manifest"

  # shellcheck disable=SC1091
  source ./.autoupdate

  # Per-run download cache, shared between the AppImage extraction below and
  # update-checksums.sh so a 100 MB AppImage is fetched at most once.
  export DL_CACHE="${WORKDIR}/.cache"
  mkdir -p "$DL_CACHE"

  # --- AUR reference state -------------------------------------------------
  # Fetched up front: it is the reference for the pkgrel decision, not just a
  # push target. Comparing against the AUR rather than against local history is
  # what makes the pkgrel bump idempotent -- once pushed, the AUR matches and
  # the next run finds nothing to do.
  # Read-only HTTPS: establishing the reference state needs no SSH key, so
  # dry runs work anywhere. Only sync-aur.sh's push is authenticated.
  local aur_pkgbuild="" aur_pkgrel="" aur_pkgver="" aur_name
  aur_name="$(pkgbuild_expand PKGBUILD 'printf %s "$pkgname"')"
  git remote remove aur-ro >/dev/null 2>&1 || true
  git remote add aur-ro "${AUR_HTTPS_BASE}/${aur_name}.git"
  if git fetch --quiet aur-ro master 2>/dev/null; then
    aur_pkgbuild="${WORKDIR}/${pkg}.aur.PKGBUILD"
    if git show FETCH_HEAD:PKGBUILD > "$aur_pkgbuild" 2>/dev/null; then
      aur_pkgrel="$(pkgbuild_get pkgrel "$aur_pkgbuild")"
      aur_pkgver="$(pkgbuild_get pkgver "$aur_pkgbuild")"
      info "AUR has ${aur_pkgver}-${aur_pkgrel}"
    else
      aur_pkgbuild=""
    fi
  else
    info "not on the AUR yet"
  fi

  # --- upstream version ----------------------------------------------------
  # A failure in here exits non-zero and is NOT mistaken for "no new version".
  local oldver newver
  oldver="$(pkgbuild_get pkgver)"
  # Checked explicitly rather than leaning on `set -e`, so the failure is
  # attributed to the lookup instead of surfacing several steps later as an
  # unrelated .SRCINFO complaint.
  newver="$("$LATEST_VERSION_CMD" .)" || die "upstream version lookup failed for ${pkg}"
  validate_version "$newver" "upstream version for ${pkg}"
  info "upstream ${newver}, local ${oldver:-<empty>}"

  local version_changed=0
  if [ "$newver" != "$oldver" ]; then
    version_changed=1
    log "new upstream version ${oldver:-<empty>} -> ${newver}"
    pkgbuild_set pkgver "$newver"
    # pkgrel is not touched here; apply_pkgrel_rule derives it from the AUR.
  fi

  # --- AppImage assets -----------------------------------------------------
  if [ "${gui:-false}" = "true" ] && [ "$version_changed" -eq 1 ]; then
    extract_appimage_assets
  fi

  # --- checksums + .SRCINFO ------------------------------------------------
  # Local sources are always re-hashed (free, no network) so a hand-edited
  # .desktop or icon self-corrects. Remote sources are only re-fetched when the
  # version moved, or on demand.
  local cs_args=()
  if [ "$version_changed" -eq 1 ] || [ -n "${FORCE_REFRESH:-}" ]; then
    cs_args+=(--remote)
  fi
  "${_here}/update-checksums.sh" "${cs_args[@]}" .

  regen_srcinfo .

  # --- pkgrel ---------------------------------------------------------------
  apply_pkgrel_rule

  # --- commit ---------------------------------------------------------------
  git add -A
  if git diff --cached --quiet; then
    # Nothing changed. Deliberately do NOT exit here: the AUR may still be out
    # of sync from a previous failed push, and an unguarded `git commit` with
    # nothing staged would exit non-zero and, under `set -e`, abort before the
    # reconcile.
    log "no local changes for ${pkg}"
  else
    local ver rel
    ver="$(pkgbuild_get pkgver)"; rel="$(pkgbuild_get pkgrel)"
    git commit --quiet -m "Updated ${pkg} to ${ver}-${rel}"
    log "committed ${pkg} ${ver}-${rel}"
  fi

  # --- publish --------------------------------------------------------------
  # AUR first: if it rejects the push, origin is left unpoisoned and the whole
  # thing is recomputed cleanly on the next run.
  "${_here}/sync-aur.sh" .

  if [ -n "${NO_GIT_PUSH:-}" ]; then
    log "NO_GIT_PUSH set: not pushing ${pkg} to origin"
  else
    git push --quiet origin HEAD
  fi
}

# Derive pkgrel so that fixing a package() bug and pushing needs no manual bump.
apply_pkgrel_rule() {
  local cur_ver cur_rel
  cur_ver="$(pkgbuild_get pkgver)"
  cur_rel="$(pkgbuild_get pkgrel)"

  # Nothing on the AUR to compare against (new package): push as-is.
  if [ -z "${aur_pkgbuild:-}" ]; then
    return 0
  fi

  # pkgrel is derived purely from the AUR reference, because the AUR is what
  # `-N` is numbered against. If the version we are about to publish differs
  # from the published one, this is a new upstream version as far as the AUR is
  # concerned and the packaging revision restarts at 1 -- whether the bump
  # happened in this run or in an earlier one that failed to push. That second
  # case is real: reflex-appimage sat at 1.0.11-4 locally against 1.0.10-4 on
  # the AUR, because the old script only reset pkgrel under FORCE_REBUILD.
  if [ "$cur_ver" != "${aur_pkgver:-}" ]; then
    if [ "$cur_rel" != "1" ]; then
      pkgbuild_set pkgrel "1"
      log "new version relative to the AUR (${aur_pkgver} -> ${cur_ver}); pkgrel ${cur_rel} -> 1"
      regen_srcinfo .
    fi
    return 0
  fi

  local base_rel="${aur_pkgrel:-0}"
  [[ "$base_rel" =~ ^[0-9]+$ ]] || base_rel=0

  if [ -n "${FORCE_REBUILD:-}" ]; then
    pkgbuild_set pkgrel "$(( base_rel + 1 ))"
    log "FORCE_REBUILD: pkgrel -> $(( base_rel + 1 ))"
    regen_srcinfo .
    return 0
  fi

  # Compare with the pkgrel line stripped, so the decision is about substantive
  # packaging content. An edit to a local source lands here too, because its
  # sha256sums entry was just regenerated. A README-only edit does not touch
  # the PKGBUILD and so correctly does not bump.
  #
  # Deliberately a shell string comparison rather than diff(1): diff lives in
  # diffutils, which archlinux:base does not ship, and a missing binary makes
  # the `if` fail, which reads as "changed" and ratchets pkgrel upward on every
  # single run. Same silent-wrong-default class of bug as the empty .SRCINFO.
  local local_body aur_body
  local_body="$(grep -v '^pkgrel=' PKGBUILD)"
  aur_body="$(grep -v '^pkgrel=' "$aur_pkgbuild")"
  if [ "$local_body" = "$aur_body" ]; then
    return 0  # identical packaging; nothing to do
  fi

  if [ "$cur_rel" = "$aur_pkgrel" ]; then
    pkgbuild_set pkgrel "$(( base_rel + 1 ))"
    log "packaging changed without a pkgrel bump; pkgrel -> $(( base_rel + 1 ))"
    regen_srcinfo .
  else
    info "pkgrel already moved by hand (${aur_pkgrel} -> ${cur_rel}); leaving it"
  fi
}

# Pull the .desktop and icon out of the AppImage so they can be shipped as
# local sources. Unchanged in substance from the old push.sh.
extract_appimage_assets() {
  local host_arr="source_$(uname -m)" entry loc img newdesktop newicon
  local candidates=()

  # A multi-arch AppImage is extracted once, against the host arch's image.
  if pkgbuild_has_array PKGBUILD "$host_arr"; then
    mapfile -t candidates < <(pkgbuild_array PKGBUILD "$host_arr")
  fi
  if [ "${#candidates[@]}" -eq 0 ]; then
    mapfile -t candidates < <(pkgbuild_array PKGBUILD source)
  fi

  img=""
  for entry in "${candidates[@]}"; do
    loc="$(source_loc "$entry")"
    if printf '%s' "${entry,,}" | grep -q "appimage" && is_remote "$entry"; then
      img="$(download_cached "$loc")"
      break
    fi
  done
  [ -n "$img" ] || { warn "gui=true but no AppImage source found; skipping asset extraction"; return 0; }

  local pkgbase
  pkgbase="$(pkgbuild_expand PKGBUILD 'printf %s "${_pkgname:-$pkgname}"')"
  newdesktop="${pkgbase}.desktop"
  newicon="${pkgbase}.png"

  local tmp; tmp="$(mktemp -d)"
  cp "$img" "${tmp}/app.AppImage"
  chmod +x "${tmp}/app.AppImage"
  ( cd "$tmp" && ./app.AppImage --appimage-extract >/dev/null 2>&1 ) \
    || { warn "could not extract ${pkgbase} AppImage; keeping existing assets"; rm -rf "$tmp"; return 0; }

  if [ -f "${tmp}/squashfs-root/${desktop}" ]; then
    cp "${tmp}/squashfs-root/${desktop}" "$newdesktop"
    sed -i "/^X-AppImage-/d;/^$/d" "$newdesktop"
    sed -i "s|^Exec=.*|Exec=${pkgbase} %U|" "$newdesktop"
    info "extracted ${newdesktop}"
  else
    warn "${desktop} not found inside the AppImage"
  fi

  if [ -f "${tmp}/squashfs-root/${icon}" ]; then
    cp "${tmp}/squashfs-root/${icon}" "$newicon"
    info "extracted ${newicon}"
  else
    warn "${icon} not found inside the AppImage"
  fi

  rm -rf "$(readlink -f "${tmp}/squashfs-root" 2>/dev/null || true)" "$tmp"
}

# One package per process, deliberately.
#
# The obvious `( update_one "$pkg" ) || { rc=1; ... }` is broken: putting a
# subshell in an && / || list disables `set -e` for its ENTIRE body, not just
# for the subshell as a unit. update_one then sails past a failed sync-aur.sh
# straight into `git push origin`, which is precisely the "origin ahead of the
# AUR" state this whole tool exists to avoid -- and it happened in production.
#
#   inner() { echo start; false; echo "REACHED CODE AFTER FAILURE"; }
#   ( inner ) || echo caught     # prints REACHED CODE AFTER FAILURE
#   ( inner )                    # correctly aborts
#
# Re-exec'ing gives each package a fresh shell whose `set -e` is intact; the
# parent's AND-OR context cannot reach across a process boundary. The CI matrix
# already passes exactly one package, so the loop only affects local runs.
if [ -n "${AUTOUPDATE_SINGLE:-}" ]; then
  update_one "$1"
  exit 0
fi

rc=0
for pkg in "$@"; do
  AUTOUPDATE_SINGLE=1 "$0" "$pkg" || { rc=1; warn "${pkg} FAILED"; }
done
exit "$rc"