#!/bin/bash

# Copyright 2021 The Go Authors. All rights reserved.
# Use of this source code is governed by a BSD-style
# license that can be found in the LICENSE file.

# Library of useful bash functions and variables.

RED=; GREEN=; YELLOW=; NORMAL=;
MAXWIDTH=0

if tput setaf 1 >& /dev/null; then
  RED=$(tput setaf 1)
  GREEN=$(tput setaf 2)
  YELLOW=$(tput setaf 3)
  NORMAL=$(tput sgr0)
  MAXWIDTH=$(( $(tput cols) - 2 ))
fi

EXIT_CODE=0
export EXIT_CODE

info() { echo -e "${GREEN}$*${NORMAL}" 1>&2; }
warn() { echo -e "${YELLOW}$*${NORMAL}" 1>&2; }
err() { echo -e "${RED}$*${NORMAL}" 1>&2; EXIT_CODE=1; }

die() {
  err "$@"
  exit 1
}

dryrun=false

# runcmd prints an info log describing the command that is about to be run, and
# then runs it. It sets EXIT_CODE to non-zero if the command fails, but does not exit
# the script.
runcmd() {
  msg="$*"
  if $dryrun; then
    echo -e "${YELLOW}dryrun${GREEN}\$ $msg${NORMAL}"
    return 0
  fi
  # Truncate command logging for narrow terminals.
  # Account for the 2 characters of '$ '.
  if [[ $MAXWIDTH -gt 0 && ${#msg} -gt $MAXWIDTH ]]; then
    msg="${msg::$(( MAXWIDTH - 3 ))}..."
  fi

  echo -e "$*\n" 1>&2;
  "$@" || err "command failed"
}