#!/usr/bin/env bash
# Resolve the latest upstream version for a package and print it on stdout.
#
# Reads the package's .autoupdate manifest (srchost/srcmntr/srcname/verstrip).
#
#   usage: latest-version.sh [package-dir]
#
# Exit 0 with a version on stdout, or exit 1 with a message on stderr.
#
# There is deliberately NO "returned nothing so assume no update" path. The old
# workflow could not tell a broken query from a quiet night: pman-helper's
# lookup hit a 404, produced an empty string, and push.sh treated it as a
# version. "Query returned nothing" is an error, not a version.

set -euo pipefail

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

pkgdir="${1:-.}"
manifest="${pkgdir}/.autoupdate"
[ -f "$manifest" ] || die "no .autoupdate manifest in ${pkgdir}"

# shellcheck disable=SC1090
source "$manifest"

: "${srchost:?manifest is missing srchost}"
: "${srcmntr:?manifest is missing srcmntr}"
: "${srcname:?manifest is missing srcname}"
verstrip="${verstrip:-}"

GIT_HOST="${GIT_HOST:-git.bjphoster.com}"

# curl that fails loudly on HTTP errors instead of returning an error page.
fetch() {
  local url="$1"; shift
  local out rc=0
  out="$(curl --silent --show-error --location --fail-with-body \
              --retry 3 --retry-delay 2 --max-time 60 "$@" "$url" 2>&1)" || rc=$?
  if [ "$rc" -ne 0 ]; then
    printf '%s\n' "$out" >&2
    die "request to ${url} failed (curl exit ${rc})"
  fi
  printf '%s' "$out"
}

case "$srchost" in
  github)
    url="https://api.github.com/repos/${srcmntr}/${srcname}/releases/latest"
    hdrs=(-H "Accept: application/vnd.github+json")
    # Optional: avoids the 60/hour unauthenticated rate limit in CI.
    [ -n "${GITHUB_TOKEN:-}" ] && hdrs+=(-H "Authorization: Bearer ${GITHUB_TOKEN}")
    body="$(fetch "$url" "${hdrs[@]}")"
    tag="$(printf '%s' "$body" | jq -r '.tag_name // empty')"
    [ -n "$tag" ] || die "no tag_name in the latest release of ${srcmntr}/${srcname}"
    ;;

  gitea)
    # NB: the correct Gitea path is /repos/{owner}/{repo}/tags. The old
    # workflows used /repos/{owner}/{repo}/repo/tags, which 404s.
    url="https://${GIT_HOST}/api/v1/repos/${srcmntr}/${srcname}/tags"
    body="$(fetch "$url" -H "Accept: application/json")"
    printf '%s' "$body" | jq -e 'type == "array"' >/dev/null 2>&1 \
      || die "unexpected response shape from ${url}"
    tag="$(printf '%s' "$body" | jq -r '.[].name' | sort -V | tail -n1)"
    [ -n "$tag" ] || die "${srcmntr}/${srcname} has no tags"
    ;;

  *)
    die "unknown srchost '${srchost}' (expected 'github' or 'gitea')"
    ;;
esac

version="$tag"
if [ -n "$verstrip" ]; then
  version="${version#"$verstrip"}"
fi

validate_version "$version" "resolved version (from tag '${tag}')"
printf '%s\n' "$version"