#!/usr/bin/env bash

# constants

MIAOU_BASH_ERROR=$(mktemp -t "$(basename "$0").XXXXXXXX" --tmpdir="/run/user/$(id -u)")
MIAOU_DEBUG=${MIAOU_DEBUG:-false}
readonly MIAOU_BASH_ERROR MIAOU_DEBUG

## functions

function is_true {
  [[ "${1:-}" == 'true' ]]
}

# FIXME: define an alias to bypass ARG evaluation when unnecessary!
# example:
#   alias toto="bash -c \"[[ \\\$MIAOU_DEBUG == 'true' ]] && echo yes \\\$* || echo nope\""
function miaou_debug {
  is_true "${MIAOU_DEBUG}" && >/dev/tty builtin echo -e "\r\e[90mDEBUG <==> \e[95m$*\e[0m" || true
}

function on_error {
  code="${1:-100}"
  miaou_debug "on_error: $code ($$ -- $BASHPID)"
  if [[ $$ == "$BASHPID" ]]; then
    >&2 echo "${BASH_SOURCE[1]}: line ${BASH_LINENO[0]}: command_error: ${code}"
    failure_type="COMMAND_ERROR"
    exit "$code"
  else
    >&2 echo "${BASH_SOURCE[1]}: line ${BASH_LINENO[0]}: subshell_error: ${code}"
    kill -PIPE $$
  fi
}

function dump_stderr {
  >&2 printf '' # force flush

  miaou_debug --stderr--
  mapfile -t tmp_error <"$MIAOU_BASH_ERROR"
  for i in "${tmp_error[@]}"; do >&4 echo -e "$i"; done
  miaou_debug --end of stderr--
}

function on_exit {
  code="${1:-0}"
  failure_type="${failure_type:-UNDEFINED}"

  dump_stderr
  miaou_debug "on_exit $code $failure_type"
}

function on_pipe {
  local code=141 # default code error for pipe
  local tmp_error regex

  mapfile -t tmp_error <"$MIAOU_BASH_ERROR"
  last_error="${tmp_error[-1]}"
  regex='.*: line [0-9]+: subshell_error: ([0-9]+)'
  [[ $last_error =~ $regex ]] && code=${BASH_REMATCH[1]} && failure_type="SUBSHELL_ERROR"

  miaou_debug on_pipe: "${code}"
  exit "$code"
}

## main

set -euo pipefail
set -E # HALT on subshell error
# set -T # DEBUG RETURN

trap 'on_error $?' ERR
trap 'on_exit $?' EXIT
trap 'on_pipe' PIPE

echo "--SOURCE scenario ${BASHPID}"
exec 3> >(tee "$MIAOU_BASH_ERROR" >/dev/null) 4>/dev/stderr
source ./test/stub/scenario.bash subshell_term 2>&3
echo "--SUCCESS scenario"