#!/usr/bin/env bash

set -Eeuo pipefail

GITEA_URL="${GITEA_URL:-https://git.awaioi.com/}"
GITEA_REPOSITORY="${GITEA_REPOSITORY:-awaioi/ERP}"
RUNNER_IMAGE="${RUNNER_IMAGE:-}"
RUNNER_CONTAINER="${RUNNER_CONTAINER:-gitea-runner}"
RUNNER_VOLUME="${RUNNER_VOLUME:-gitea-runner-data}"
RUNNER_LABELS="${RUNNER_LABELS:-ubuntu-latest:docker://docker.gitea.com/runner-images:ubuntu-latest}"

log() {
  printf '[Gitea Runner] %s\n' "$*"
}

fail() {
  printf '[Gitea Runner] ERROR: %s\n' "$*" >&2
  exit 1
}

command -v docker >/dev/null 2>&1 || fail "docker is not installed"
docker info >/dev/null 2>&1 || fail "docker is not running or the current user cannot access it"

find_gitea_container() {
  local container_id image name

  while read -r container_id image name; do
    case "$image" in
      gitea/gitea:* | gitea/gitea@* | */gitea/gitea:* | */gitea/gitea@* | docker.gitea.com/gitea:* | docker.gitea.com/gitea@*)
        printf '%s\n' "$container_id"
        return 0
        ;;
    esac
  done < <(docker ps --format '{{.ID}} {{.Image}} {{.Names}}')

  while read -r container_id name; do
    case "$name" in
      *runner*) ;;
      *gitea*)
        printf '%s\n' "$container_id"
        return 0
        ;;
    esac
  done < <(docker ps --format '{{.ID}} {{.Names}}')

  return 1
}

pull_runner_image() {
  local candidate
  local -a candidates

  if [[ -n "$RUNNER_IMAGE" ]]; then
    candidates=("$RUNNER_IMAGE")
  else
    candidates=(
      "docker.gitea.com/runner:3.0.2"
      "docker.gitea.com/act_runner:3.0.2"
      "gitea/runner:3.0.2"
    )
  fi

  for candidate in "${candidates[@]}"; do
    log "Pulling $candidate"
    if docker pull "$candidate"; then
      RUNNER_IMAGE="$candidate"
      return 0
    fi
    log "Image source failed; trying the next source"
  done

  fail "all official Gitea Runner image sources failed"
}

GITEA_CONTAINER="$(find_gitea_container || true)"
[[ -n "$GITEA_CONTAINER" ]] || fail "no running Gitea container was found"

TMP_DIR="$(mktemp -d)"
TOKEN_FILE="$TMP_DIR/runner-token"
BOOTSTRAP_RUNNING=0

cleanup() {
  if [[ "$BOOTSTRAP_RUNNING" == "1" ]]; then
    docker rm -f "$RUNNER_CONTAINER" >/dev/null 2>&1 || true
  fi
  if [[ -f "$TOKEN_FILE" ]]; then
    : >"$TOKEN_FILE"
  fi
  rm -rf -- "$TMP_DIR"
}
trap cleanup EXIT

log "Generating a repository-scoped registration token"
if ! docker exec -u git "$GITEA_CONTAINER" gitea actions generate-runner-token \
  --scope "$GITEA_REPOSITORY" | tr -d '\r' | tail -n 1 >"$TOKEN_FILE"; then
  fail "Gitea could not generate a runner token"
fi
[[ -s "$TOKEN_FILE" ]] || fail "Gitea returned an empty runner token"
chmod 600 "$TOKEN_FILE"

pull_runner_image
docker rm -f "$RUNNER_CONTAINER" >/dev/null 2>&1 || true
docker volume create "$RUNNER_VOLUME" >/dev/null
docker run --rm --entrypoint /bin/rm \
  -v "$RUNNER_VOLUME:/data" \
  "$RUNNER_IMAGE" -f /data/.runner

log "Registering the runner"
docker run -d \
  --name "$RUNNER_CONTAINER" \
  -v "$RUNNER_VOLUME:/data" \
  -v "$TOKEN_FILE:/run/secrets/gitea_runner_token:ro,Z" \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e "GITEA_INSTANCE_URL=$GITEA_URL" \
  -e GITEA_RUNNER_REGISTRATION_TOKEN_FILE=/run/secrets/gitea_runner_token \
  -e "GITEA_RUNNER_NAME=erp-release-$(hostname -s)" \
  -e "GITEA_RUNNER_LABELS=$RUNNER_LABELS" \
  -e GITEA_MAX_REG_ATTEMPTS=24 \
  "$RUNNER_IMAGE" >/dev/null
BOOTSTRAP_RUNNING=1

READY=0
for ((attempt = 1; attempt <= 60; attempt++)); do
  if docker exec "$RUNNER_CONTAINER" test -s /data/.runner 2>/dev/null; then
    READY=1
    break
  fi
  if [[ "$(docker inspect -f '{{.State.Running}}' "$RUNNER_CONTAINER" 2>/dev/null || true)" != "true" ]]; then
    break
  fi
  sleep 2
done

if [[ "$READY" != "1" ]]; then
  docker logs --tail 100 "$RUNNER_CONTAINER" >&2 || true
  fail "runner registration failed"
fi

docker logs --tail 30 "$RUNNER_CONTAINER" || true
docker rm -f "$RUNNER_CONTAINER" >/dev/null
BOOTSTRAP_RUNNING=0
: >"$TOKEN_FILE"

log "Starting the persistent runner without the registration token"
docker run -d \
  --name "$RUNNER_CONTAINER" \
  --restart unless-stopped \
  -v "$RUNNER_VOLUME:/data" \
  -v /var/run/docker.sock:/var/run/docker.sock \
  -e "GITEA_INSTANCE_URL=$GITEA_URL" \
  -e "GITEA_RUNNER_NAME=erp-release-$(hostname -s)" \
  -e "GITEA_RUNNER_LABELS=$RUNNER_LABELS" \
  "$RUNNER_IMAGE" >/dev/null

sleep 5
[[ "$(docker inspect -f '{{.State.Running}}' "$RUNNER_CONTAINER")" == "true" ]] || {
  docker logs --tail 100 "$RUNNER_CONTAINER" >&2 || true
  fail "runner container stopped after registration"
}

log "Runner is online; queued release jobs can now continue"
docker ps --filter "name=^/${RUNNER_CONTAINER}$" \
  --format 'table {{.Names}}\t{{.Image}}\t{{.Status}}'
docker logs --tail 80 "$RUNNER_CONTAINER" || true