#!/usr/bin/env bash

function error_handler() {
  >&2 echo "Exited with BAD EXIT CODE '${2}' in ${0} script at line: ${1}."
  exit "$2"
}
trap 'error_handler ${LINENO} $?' ERR
set -o errtrace -o errexit -o nounset -o pipefail

# run migrations
export FLASK_APP=/app/src/spiffworkflow_backend

if [[ "${SPIFFWORKFLOW_BACKEND_WAIT_FOR_DB_TO_BE_READY:-}" == "true" ]]; then
  echo 'Waiting for db to be ready...'
  poetry run python ./bin/wait_for_db_to_be_ready.py
fi

if [[ "${SPIFFWORKFLOW_BACKEND_DOWNGRADE_DB:-}" == "true" ]]; then
  echo 'Downgrading database...'
  poetry run flask db downgrade
fi

if [[ "${SPIFFWORKFLOW_BACKEND_UPGRADE_DB:-}" == "true" ]]; then
  echo 'Upgrading database...'
  poetry run flask db upgrade
fi

if [[ -z "${GUNICORN_LOG_LEVEL:-}" ]]; then
  GUNICORN_LOG_LEVEL=debug
fi

if [[ -z "${GUNICORN_TIMEOUT_SECONDS:-}" ]]; then
  GUNICORN_TIMEOUT_SECONDS=90
fi

port="${SPIFFWORKFLOW_BACKEND_PORT:-}"
if [[ -z "$port" ]]; then
  port=7000
fi

additional_args=""

app_root="${SPIFFWORKFLOW_BACKEND_APPLICATION_ROOT:-}"
if [[ -n "$app_root" ]] && [[ "${app_root}" != "/" ]]; then
  additional_args="${additional_args} -e SCRIPT_NAME=${app_root}"
fi

# HACK: if loading fixtures for acceptance tests when we do not need multiple workers
# it causes issues with attempting to add duplicate data to the db
worker_count=4
if [[ "${SPIFFWORKFLOW_BACKEND_LOAD_FIXTURE_DATA:-}" == "true" ]]; then
  worker_count=1
fi

if [[ "${SPIFFWORKFLOW_BACKEND_RUN_DATA_SETUP:-}" != "false" ]]; then
  SPIFFWORKFLOW_BACKEND_FAIL_ON_INVALID_PROCESS_MODELS=false poetry run python bin/save_all_bpmn.py
fi

if [[ -n "${SPIFFWORKFLOW_BACKEND_GIT_SSH_PRIVATE_KEY:-}" ]]; then
  if [[ -z "${SPIFFWORKFLOW_BACKEND_GIT_SSH_PRIVATE_KEY_PATH:-}" ]]; then
    export SPIFFWORKFLOW_BACKEND_GIT_SSH_PRIVATE_KEY_PATH=$(mktemp /tmp/ssh_private_key.XXXXXX)
  fi
  chmod 600 "${SPIFFWORKFLOW_BACKEND_GIT_SSH_PRIVATE_KEY_PATH}"
  echo "${SPIFFWORKFLOW_BACKEND_GIT_SSH_PRIVATE_KEY}" >"${SPIFFWORKFLOW_BACKEND_GIT_SSH_PRIVATE_KEY_PATH}"
fi

# Assure that the the Process Models Directory is initialized as a git repo
git init "${SPIFFWORKFLOW_BACKEND_BPMN_SPEC_ABSOLUTE_DIR}"
git config --global --add safe.directory "${SPIFFWORKFLOW_BACKEND_BPMN_SPEC_ABSOLUTE_DIR}"

if [[ -z "${SPIFFWORKFLOW_BACKEND_THREADS_PER_WORKER:-}" ]]; then
  # default to 3 * 2 = 6 threads per worker
  # you may want to configure threads_to_use_per_core based on whether your workload is more cpu intensive or more I/O intensive:
  #   cpu heavy, make it smaller
  #   I/O heavy, make it larger
  threads_to_use_per_core=3

  # https://stackoverflow.com/a/55423170/6090676
  # if we had access to python (i'm not sure i want to run another python script here),
  # we could do something like this (on linux) to get the number of cores available to this process and a better estimate of a
  # reasonable num_cores_multiple_for_threads
  # if hasattr(os, 'sched_getaffinity')
  #   number_of_available_cores = os.sched_getaffinity(0)
  # BUT the python solution isn't even as portable as this one, which is mostly posix compliant and works on linux/mac/freebsd.
  num_cores_multiple_for_threads=$(getconf _NPROCESSORS_ONLN 2>/dev/null || getconf NPROCESSORS_ONLN 2>/dev/null || echo 1)

  SPIFFWORKFLOW_BACKEND_THREADS_PER_WORKER=$((threads_to_use_per_core * num_cores_multiple_for_threads))
  export SPIFFWORKFLOW_BACKEND_THREADS_PER_WORKER
fi

# DELETE after this runs on all necessary environments
# TODO: make a system somewhat like schema migrations (storing versions in a db table) to handle data migrations
poetry run python ./bin/data_migrations/version_1_3.py

# --worker-class is not strictly necessary, since setting threads will automatically set the worker class to gthread, but meh
export IS_GUNICORN="true"
# THIS MUST BE THE LAST COMMAND!
exec poetry run gunicorn ${additional_args}  \
  --bind "0.0.0.0:$port"  \
  --preload \
  --worker-class "gthread" \
  --workers="$worker_count"  \
  --threads "$SPIFFWORKFLOW_BACKEND_THREADS_PER_WORKER" \
  --limit-request-line 8192  \
  --timeout "$GUNICORN_TIMEOUT_SECONDS"  \
  --capture-output  \
  --access-logfile '-'  \
  --log-level "$GUNICORN_LOG_LEVEL" wsgi:app