#!/bin/sh

cleanup() {
  [ -n "${NVM_DIR}" ] && [ -d "${NVM_DIR}" ] && rm -rf "${NVM_DIR}"
  unset -f die cleanup nvm_remote_version nvm_has_executable nvm_binary_available \
    nvm_install_binary nvm_install_source nvm_get_make_jobs
  unset NVM_DIR version SOURCE_MARKER OUTPUT EXIT_CODE
}

die() { echo "$@" ; cleanup ; exit 1; }

: nvm.sh
\. ../../../nvm.sh

unset npm_config_prefix NPM_CONFIG_PREFIX

NVM_DIR="$(mktemp -d)"
[ -n "${NVM_DIR}" ] || die 'unable to create temp NVM_DIR'
version='v20.0.0'
SOURCE_MARKER="${NVM_DIR}/source-was-attempted"

# Stay offline; make the binary download always fail and record any attempt to
# compile from source.
nvm_remote_version() { nvm_echo "${version}"; }
nvm_has_executable() { return 0; }
nvm_binary_available() { return 0; }
nvm_get_make_jobs() { NVM_MAKE_JOBS=1; }
nvm_install_binary() { return 1; }
nvm_install_source() { command touch "${SOURCE_MARKER}"; return 1; }

# Default: a failed binary download falls back to a source compile.
rm -f "${SOURCE_MARKER}"
nvm install "${version}" > /dev/null 2>&1
[ -f "${SOURCE_MARKER}" ] || die 'default behaviour should fall back to source when the binary fails'

# NVM_NO_SOURCE_FALLBACK=1: a failed binary download must NOT compile from source.
rm -f "${SOURCE_MARKER}"
NVM_NO_SOURCE_FALLBACK=1 nvm install "${version}" > /dev/null 2>&1; EXIT_CODE=$?
[ ! -f "${SOURCE_MARKER}" ] || die 'NVM_NO_SOURCE_FALLBACK=1 should not fall back to source'
[ "${EXIT_CODE}" != "0" ] || die 'a failed binary install with NVM_NO_SOURCE_FALLBACK=1 should be non-zero'

# NVM_NO_SOURCE_FALLBACK=1 combined with -s would skip both methods: a conflict.
OUTPUT="$(NVM_NO_SOURCE_FALLBACK=1 nvm install -s "${version}" 2>&1)"; EXIT_CODE=$?
[ "${EXIT_CODE}" = "6" ] || die "expected exit code 6 for -s with NVM_NO_SOURCE_FALLBACK=1, got ${EXIT_CODE}"
case "${OUTPUT}" in
  *'skip install from both binary and source'*) ;;
  *) die "expected a conflict message, got >${OUTPUT}<" ;;
esac

cleanup