#!/usr/bin/env bash
set -euo pipefail

repo_root="$(cd "$(dirname "${BASH_SOURCE[0]}")/../.." && pwd)"
# shellcheck source=scripts/apk/package-lib.sh
source "${repo_root}/scripts/apk/package-lib.sh"

mode="${APK_UPDATE_CHECK_MODE:-warn}"
if [[ "${mode}" != "warn" && "${mode}" != "fail" ]]; then
  printf 'APK_UPDATE_CHECK_MODE must be warn or fail\n' >&2
  exit 2
fi

github_latest_release() {
  local repo="$1"
  local response

  response="$(curl -fsSL \
    -H 'Accept: application/vnd.github+json' \
    -H 'X-GitHub-Api-Version: 2022-11-28' \
    "https://api.github.com/repos/${repo}/releases/latest" 2>/dev/null)" || return 1
  printf '%s\n' "${response}" | jq -er '.tag_name'
}

github_release_rows() {
  local repo="$1"
  local current_tag="$2"
  local page=1
  local response
  local release_count

  while :; do
    response="$(curl -fsSL \
      -H 'Accept: application/vnd.github+json' \
      -H 'X-GitHub-Api-Version: 2022-11-28' \
      "https://api.github.com/repos/${repo}/releases?per_page=100&page=${page}" 2>/dev/null)" || return 1
    release_count="$(printf '%s\n' "${response}" | jq -er 'if type == "array" then length else error("expected release array") end')" || return 1
    [[ "${release_count}" -gt 0 ]] || return 0

    printf '%s\n' "${response}" | jq -r '
      .[]
      | select(.draft | not)
      | select(.prerelease | not)
      | [
          .tag_name,
          (.published_at // "-"),
          (.name // .tag_name),
          .html_url,
          (
            (.body // "")
            | gsub("[\\r\\n\\t]+"; " ")
            | gsub("[`*_>#]"; "")
            | gsub(" +"; " ")
            | gsub("^ +"; "")
            | gsub(" +$"; "")
            | if length > 240 then .[0:237] + "..." else . end
          )
        ]
      | @tsv
    '

    if printf '%s\n' "${response}" | jq -e --arg tag "${current_tag}" '
      any(.[]; .tag_name == $tag and (.draft | not) and (.prerelease | not))
    ' >/dev/null; then
      return 0
    fi
    page=$((page + 1))
  done
}

apkbuild_value() {
  local package_dir="$1"
  local key="$2"

  awk -F= -v key="${key}" '
    $1 == key {
      value = $2
      gsub(/["'\'']/, "", value)
      gsub(/^[ \t]+|[ \t]+$/, "", value)
      print value
      exit
    }
  ' "${package_dir}/APKBUILD"
}

load_update_metadata() {
  local package_dir="$1"
  local metadata="${package_dir}/update-check.conf"

  provider=""
  repo=""
  version_prefix="v"

  if [[ ! -f "${metadata}" ]]; then
    return 1
  fi

  # shellcheck source=/dev/null
  source "${metadata}"

  if [[ "${provider}" != "github" || -z "${repo}" ]]; then
    return 1
  fi
}

normalize_version() {
  local version="$1"
  local prefix="$2"

  case "${prefix}" in
    none|"")
      printf '%s\n' "${version}"
      ;;
    *)
      printf '%s\n' "${version#"${prefix}"}"
      ;;
  esac
}

version_is_newer() {
  local latest="$1"
  local current="$2"
  local apk_result
  local sorted

  if [[ "${latest}" == "${current}" ]]; then
    return 1
  fi

  if command -v apk >/dev/null 2>&1; then
    apk_result="$(apk version -t "${latest}-r0" "${current}-r0" 2>/dev/null || true)"
    [[ "${apk_result}" == ">" ]]
    return
  fi

  if sort -V </dev/null >/dev/null 2>&1; then
    sorted="$(printf '%s\n%s\n' "${current}" "${latest}" | sort -V | tail -n 1)"
    [[ "${sorted}" == "${latest}" && "${latest}" != "${current}" ]]
    return
  fi

  return 0
}

printf '%-14s %-14s %-14s %-18s %s\n' "PACKAGE" "CURRENT" "LATEST" "STATUS" "UPSTREAM"

has_update=0
has_unknown=0
release_details=""

while IFS= read -r package_dir; do
  apk_validate_package_dir "${package_dir}"

  package_name="$(apk_package_name "${package_dir}")"
  current_version="$(apkbuild_value "${package_dir}" "pkgver")"
  status="unknown"
  latest_version="-"
  upstream_url="-"

  if load_update_metadata "${package_dir}"; then
    upstream_url="https://github.com/${repo}/releases"
    if latest_tag="$(github_latest_release "${repo}")" && [[ -n "${latest_tag}" ]]; then
      latest_version="$(normalize_version "${latest_tag}" "${version_prefix}")"
      if version_is_newer "${latest_version}" "${current_version}"; then
        status="update-available"
        has_update=1
        package_details="${package_name}: ${current_version} -> ${latest_version}"
        case "${version_prefix}" in
          none|"") current_tag="${current_version}" ;;
          *) current_tag="${version_prefix}${current_version}" ;;
        esac
        if release_rows="$(github_release_rows "${repo}" "${current_tag}")" && [[ -n "${release_rows}" ]]; then
          current_tag_found=0
          while IFS=$'\t' read -r release_tag published_at release_name release_url release_excerpt; do
            [[ -n "${release_tag}" ]] || continue
            release_version="$(normalize_version "${release_tag}" "${version_prefix}")"
            if [[ "${release_tag}" == "${current_tag}" ]]; then
              current_tag_found=1
            fi
            if version_is_newer "${release_version}" "${current_version}"; then
              package_details+=$'\n'
              package_details+="  ${release_version} (${published_at}) — ${release_name}"
              package_details+=$'\n'
              package_details+="    ${release_url}"
              if [[ -n "${release_excerpt}" ]]; then
                package_details+=$'\n'
                package_details+="    ${release_excerpt}"
              fi
            fi
          done <<< "${release_rows}"
          if [[ "${current_tag_found}" == 0 ]]; then
            package_details+=$'\n'
            package_details+="  Note: current release tag ${current_tag} was not found; listed releases compare newer than ${current_version}."
          fi
        else
          package_details+=$'\n'
          package_details+="  Note: release details could not be fetched."
        fi
        release_details+=$'\n'
        release_details+="${package_details}"
      else
        status="current"
      fi
    else
      has_unknown=1
    fi
  else
    has_unknown=1
  fi

  printf '%-14s %-14s %-14s %-18s %s\n' \
    "${package_name}" \
    "${current_version:-"-"}" \
    "${latest_version}" \
    "${status}" \
    "${upstream_url}"
done < <(apk_package_dirs "${repo_root}")

if [[ -n "${release_details}" ]]; then
  printf '\nRelease details:%s\n' "${release_details}"
fi

if [[ "${mode}" == "fail" && ( "${has_update}" -ne 0 || "${has_unknown}" -ne 0 ) ]]; then
  exit 1
fi