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

separator() {
  printf '\n%s\n' '=================================================='
}

section() {
  separator
  printf '%s\n' "$1"
  printf '%s\n' '--------------------------------------------------'
}

info() {
  printf '[INFO] %s\n' "$1"
}

success() {
  printf '[OK]   %s\n' "$1"
}

warn() {
  printf '[WARN] %s\n' "$1"
}

fail() {
  printf '[ERR]  %s\n' "$1" >&2
}

is_empty_or_null() {
  [ -z "${1:-}" ] || [ "${1:-}" = "null" ]
}

require_value() {
  local name="$1"
  local value="$2"

  info "$name=$value"
  if is_empty_or_null "$value"; then
    fail "$name is required"
    exit 1
  fi
}

require_integer() {
  local name="$1"
  local value="$2"

  if ! [[ "$value" =~ ^[0-9]+$ ]]; then
    fail "$name must be a non-negative integer"
    exit 1
  fi
}

fetch_all_pages() {
  local base_url="$1"
  local all_json='[]'
  local page=1
  local page_url page_json

  while :; do
    page_url="$base_url?page=$page"
    page_json="$(curl -fsS "${auth_header[@]}" "$page_url")"

    if [ "$(jq 'length' <<<"$page_json")" -eq 0 ]; then
      break
    fi

    all_json="$(jq -s 'add' <<<"$all_json"$'\n'"$page_json")"
    page=$((page + 1))
  done

  printf '%s' "$all_json"
}

section "參數檢查"
require_value "GITEA_SERVER_URL" "$GITEA_SERVER_URL"
require_value "GITEA_REPOSITORY" "$GITEA_REPOSITORY"
require_value "KEEP_COUNT" "$KEEP_COUNT"
require_integer "KEEP_COUNT" "$KEEP_COUNT"

if is_empty_or_null "${GITEA_TOKEN:-}"; then
  warn "GITEA_TOKEN is empty; release API calls will be anonymous"
else
  info "GITEA_TOKEN=[redacted]"
fi

release_api_url="$GITEA_SERVER_URL/api/v1/repos/$GITEA_REPOSITORY/releases"
auth_header=()

if ! is_empty_or_null "${GITEA_TOKEN:-}"; then
  auth_header=(-H "Authorization: token $GITEA_TOKEN")
fi

section "取得成品資訊"
info "GET $release_api_url"

release_json="$(fetch_all_pages "$release_api_url")"
release_json="$(jq -e 'sort_by(.created_at) | reverse' <<<"$release_json")"
release_count="$(jq 'length' <<<"$release_json")"
normal_release_json="$(jq -c '[.[] | select(((.tag_name // "") | test("-beta\\.")) | not)]' <<<"$release_json")"
beta_release_json="$(jq -c '[.[] | select((.tag_name // "") | test("-beta\\."))]' <<<"$release_json")"
normal_release_count="$(jq 'length' <<<"$normal_release_json")"
beta_release_count="$(jq 'length' <<<"$beta_release_json")"

info "RELEASE_COUNT=$release_count"
info "NORMAL_RELEASE_COUNT=$normal_release_count"
info "BETA_RELEASE_COUNT=$beta_release_count"
info "KEEP_COUNT=$KEEP_COUNT"

normal_release_to_delete='[]'
if [ "$normal_release_count" -gt "$KEEP_COUNT" ]; then
  normal_release_to_delete="$(jq -c ".[$KEEP_COUNT:]" <<<"$normal_release_json")"
fi

beta_release_to_delete='[]'
if [ "$beta_release_count" -gt "$KEEP_COUNT" ]; then
  beta_release_to_delete="$(jq -c ".[$KEEP_COUNT:]" <<<"$beta_release_json")"
fi

release_to_delete="$(jq -c -s 'add' <<<"$normal_release_to_delete"$'\n'"$beta_release_to_delete")"
release_to_delete_count="$(jq 'length' <<<"$release_to_delete")"

if [ "$release_to_delete_count" -eq 0 ]; then
  success "沒有需要清理的舊版本成品"
else
  section "刪除舊版本成品"
  info "DELETE_RELEASE_COUNT=$release_to_delete_count"

  while IFS= read -r release_item; do
    [ -z "$release_item" ] && continue

    release_id="$(jq -r '.id' <<<"$release_item")"
    release_tag="$(jq -r '.tag_name' <<<"$release_item")"
    release_name="$(jq -r '.name' <<<"$release_item")"

    if is_empty_or_null "$release_id"; then
      warn "略過沒有 id 的成品: $release_tag ($release_name)"
      continue
    fi

    delete_url="$GITEA_SERVER_URL/api/v1/repos/$GITEA_REPOSITORY/releases/$release_id"
    info "DELETE $release_tag ($release_name)"

    delete_code="$(curl -sS -o /dev/null -w "%{http_code}" -X DELETE "${auth_header[@]}" "$delete_url")"

    if [ "$delete_code" -eq 204 ]; then
      success "成功刪除: $release_tag ($release_name)"
    else
      fail "刪除失敗: $release_tag ($release_name), HTTP $delete_code"
    fi
  done < <(jq -c '.[]' <<<"$release_to_delete")
fi

section "刪除未指定 release 的 tag"

# 重新取得 release 清單，得到刪除舊版本後仍指定 tag 的成品
current_release_json="$(fetch_all_pages "$release_api_url")"
release_tags_json="$(jq -c '[.[].tag_name]' <<<"$current_release_json")"

tag_api_url="$GITEA_SERVER_URL/api/v1/repos/$GITEA_REPOSITORY/tags"
info "GET $tag_api_url"

tag_json="$(fetch_all_pages "$tag_api_url")"
tag_count="$(jq 'length' <<<"$tag_json")"
info "TAG_COUNT=$tag_count"

while IFS= read -r tag_item; do
  [ -z "$tag_item" ] && continue

  tag_name="$(jq -r '.name' <<<"$tag_item")"

  if is_empty_or_null "$tag_name"; then
    warn "略過沒有名稱的 tag"
    continue
  fi

  if [ "$(jq --arg name "$tag_name" 'any(.[]; . == $name)' <<<"$release_tags_json")" = "true" ]; then
    info "保留指定 release 的 tag: $tag_name"
    continue
  fi

  delete_url="$tag_api_url/$tag_name"
  info "DELETE tag $tag_name"

  delete_code="$(curl -sS -o /dev/null -w "%{http_code}" -X DELETE "${auth_header[@]}" "$delete_url")"

  if [ "$delete_code" -eq 204 ]; then
    success "成功刪除未指定 release 的 tag: $tag_name"
  else
    fail "刪除 tag 失敗: $tag_name, HTTP $delete_code"
  fi
done < <(jq -c '.[]' <<<"$tag_json")

separator