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

export PATH="/run/current-system/sw/bin:/usr/bin:/bin:${PATH}"

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
SOURCE_FLAKE_ROOT="${ULTRACLOUD_BAREMETAL_E2E_SOURCE_FLAKE_ROOT:-$(cd "${SCRIPT_DIR}/../.." && pwd)}"
TASK_ID="0de75570-dabd-471b-95fe-5898c54e2e8c"
WORK_ROOT="${ULTRACLOUD_WORK_ROOT:-${PWD}/work}"
LOG_ROOT="${1:-${ULTRACLOUD_BAREMETAL_E2E_LOG_ROOT:-${WORK_ROOT}/baremetal-iso-e2e/${TASK_ID}}}"
STATE_DIR="${ULTRACLOUD_BAREMETAL_STATE_DIR:-${LOG_ROOT}/state}"

log() {
  printf '[baremetal-iso-e2e-runner] %s\n' "$*"
}

die() {
  printf '[baremetal-iso-e2e-runner] ERROR: %s\n' "$*" >&2
  exit 1
}

host_cpu_count() {
  local count
  count="$(getconf _NPROCESSORS_ONLN 2>/dev/null || nproc 2>/dev/null || echo 1)"
  if [[ ! "${count}" =~ ^[0-9]+$ ]] || (( count < 1 )); then
    count=1
  fi
  printf '%s\n' "${count}"
}

default_local_nix_max_jobs() {
  local cpu_count="$1"
  if (( cpu_count <= 2 )); then
    printf '1\n'
    return 0
  fi
  printf '%s\n' "$(( (cpu_count + 1) / 2 ))"
}

default_local_nix_build_cores() {
  local cpu_count="$1"
  local max_jobs="$2"
  local build_cores=1
  if (( max_jobs > 0 )); then
    build_cores="$(( cpu_count / max_jobs ))"
  fi
  if (( build_cores < 1 )); then
    build_cores=1
  fi
  printf '%s\n' "${build_cores}"
}

append_nix_config_line() {
  local line="$1"
  if [[ -n "${NIX_CONFIG:-}" ]]; then
    NIX_CONFIG+=$'\n'
  fi
  NIX_CONFIG+="${line}"
}

host_nested_param_path() {
  if [[ -f /sys/module/kvm_intel/parameters/nested ]]; then
    printf '%s\n' /sys/module/kvm_intel/parameters/nested
  elif [[ -f /sys/module/kvm_amd/parameters/nested ]]; then
    printf '%s\n' /sys/module/kvm_amd/parameters/nested
  fi
}

require_baremetal_kvm_host() {
  [[ -e /dev/kvm ]] || die "/dev/kvm is missing; baremetal-iso-e2e requires host KVM"
  [[ -r /dev/kvm && -w /dev/kvm ]] || die "/dev/kvm is not readable and writable for $(id -un)"
}

prepare_runtime_dirs() {
  local cpu_count default_max_jobs default_build_cores

  cpu_count="$(host_cpu_count)"
  default_max_jobs="$(default_local_nix_max_jobs "${cpu_count}")"
  default_build_cores="$(default_local_nix_build_cores "${cpu_count}" "${default_max_jobs}")"

  export ULTRACLOUD_WORK_ROOT="${WORK_ROOT}"
  export TMPDIR="${TMPDIR:-${WORK_ROOT}/tmp}"
  export XDG_CACHE_HOME="${XDG_CACHE_HOME:-${WORK_ROOT}/xdg-cache}"
  export ULTRACLOUD_LOCAL_NIX_MAX_JOBS="${ULTRACLOUD_LOCAL_NIX_MAX_JOBS:-${default_max_jobs}}"
  export ULTRACLOUD_LOCAL_NIX_BUILD_CORES="${ULTRACLOUD_LOCAL_NIX_BUILD_CORES:-${default_build_cores}}"
  export ULTRACLOUD_BAREMETAL_STATE_DIR="${STATE_DIR}"
  export ULTRACLOUD_BAREMETAL_FORCE_TCG=0
  export ULTRACLOUD_REPO_ROOT="${SOURCE_FLAKE_ROOT}"
  export ULTRACLOUD_BAREMETAL_PROOF_MODEL="${ULTRACLOUD_BAREMETAL_PROOF_MODEL:-materialized-check-runner}"

  append_nix_config_line "builders ="
  append_nix_config_line "max-jobs = ${ULTRACLOUD_LOCAL_NIX_MAX_JOBS}"
  append_nix_config_line "cores = ${ULTRACLOUD_LOCAL_NIX_BUILD_CORES}"
  append_nix_config_line "experimental-features = nix-command flakes"
  append_nix_config_line "warn-dirty = false"
  export NIX_CONFIG

  mkdir -p "${TMPDIR}" "${XDG_CACHE_HOME}" "${WORK_ROOT}" "${LOG_ROOT}" "${STATE_DIR}"
}

git_value() {
  local repo_root="$1"
  shift
  if git -C "${repo_root}" rev-parse --is-inside-work-tree >/dev/null 2>&1; then
    git -C "${repo_root}" "$@"
  else
    printf 'unavailable\n'
  fi
}

capture_environment() {
  {
    printf 'task_id=%s\n' "${TASK_ID}"
    printf 'execution_model=%s\n' "${ULTRACLOUD_BAREMETAL_PROOF_MODEL}"
    printf 'started_at=%s\n' "$(date -Is)"
    printf 'source_flake_root=%s\n' "${SOURCE_FLAKE_ROOT}"
    printf 'invoked_from=%s\n' "${PWD}"
    printf 'work_root=%s\n' "${WORK_ROOT}"
    printf 'log_root=%s\n' "${LOG_ROOT}"
    printf 'state_dir=%s\n' "${STATE_DIR}"
    printf 'source_branch=%s\n' "$(git_value "${PWD}" branch --show-current)"
    printf 'source_commit=%s\n' "$(git_value "${PWD}" rev-parse HEAD)"
    printf 'host_cpu_count=%s\n' "$(host_cpu_count)"
    printf 'ultracloud_local_nix_max_jobs=%s\n' "${ULTRACLOUD_LOCAL_NIX_MAX_JOBS}"
    printf 'ultracloud_local_nix_build_cores=%s\n' "${ULTRACLOUD_LOCAL_NIX_BUILD_CORES}"
    printf 'tmpdir=%s\n' "${TMPDIR}"
    printf 'xdg_cache_home=%s\n' "${XDG_CACHE_HOME}"
    printf 'nix_version=%s\n' "$(nix --version)"
    printf 'nix_builders=%s\n' "$(nix config show builders 2>/dev/null | awk -F' = ' 'NR==1 { print $2 }')"
    printf 'kvm_present=%s\n' "$([[ -e /dev/kvm ]] && echo yes || echo no)"
    printf 'kvm_access=%s\n' "$([[ -r /dev/kvm && -w /dev/kvm ]] && echo rw || echo no)"
    if [[ -e /dev/kvm ]]; then
      printf 'kvm_stat=%s\n' "$(stat -c '%A %U %G %t:%T' /dev/kvm)"
    fi
    local nested_path
    nested_path="$(host_nested_param_path || true)"
    if [[ -n "${nested_path}" ]]; then
      printf 'nested_param_path=%s\n' "${nested_path}"
      printf 'nested_param_value=%s\n' "$(<"${nested_path}")"
    fi
  } >"${LOG_ROOT}/environment.txt"
}

run_case() {
  local name="$1"
  local timeout_secs="$2"
  shift 2

  local logfile="${LOG_ROOT}/${name}.log"
  local metafile="${LOG_ROOT}/${name}.meta"
  local started_at ended_at rc

  started_at="$(date -Is)"
  printf 'name=%s\n' "${name}" >"${metafile}"
  printf 'started_at=%s\n' "${started_at}" >>"${metafile}"
  printf 'timeout_secs=%s\n' "${timeout_secs}" >>"${metafile}"
  printf 'command=' >>"${metafile}"
  printf '%q ' "$@" >>"${metafile}"
  printf '\n' >>"${metafile}"

  log "running ${name}: $*"
  set +e
  timeout --signal=TERM --kill-after=120 "${timeout_secs}" "$@" 2>&1 | tee "${logfile}"
  rc=${PIPESTATUS[0]}
  set -e

  ended_at="$(date -Is)"
  printf 'ended_at=%s\n' "${ended_at}" >>"${metafile}"
  printf 'exit_code=%s\n' "${rc}" >>"${metafile}"

  if (( rc == 124 )); then
    log "${name} timed out after ${timeout_secs}s"
  elif (( rc == 0 )); then
    log "${name} passed"
  else
    log "${name} failed with exit ${rc}"
  fi

  return "${rc}"
}

main() {
  prepare_runtime_dirs
  require_baremetal_kvm_host
  capture_environment

  run_case baremetal-iso-e2e 21600 \
    env \
      ULTRACLOUD_REPO_ROOT="${SOURCE_FLAKE_ROOT}" \
      ULTRACLOUD_WORK_ROOT="${WORK_ROOT}" \
      ULTRACLOUD_BAREMETAL_STATE_DIR="${STATE_DIR}" \
      ULTRACLOUD_BAREMETAL_FORCE_TCG=0 \
      ULTRACLOUD_BAREMETAL_PROOF_MODEL="${ULTRACLOUD_BAREMETAL_PROOF_MODEL}" \
      bash "${SOURCE_FLAKE_ROOT}/nix/test-cluster/verify-baremetal-iso.sh"

  log "baremetal-iso-e2e exact proof passed; logs in ${LOG_ROOT}"
}

main "$@"