shuz.sh

# Environment
# ------------------------------------------

# Stores sourcing script location in script_dir variable
script_dir=$(cd "$(dirname "${BASH_SOURCE[1]}")" && pwd)


# Terminal colors
# ------------------------------------------

# Clears styling
noc='\033[0m'

# Foreground colors
bold='\033[0;1m'
black='\033[0;30m'
red='\033[0;31m'
green='\033[0;32m'
yellow='\033[0;33m'
blue='\033[0;34m'
magenta='\033[0;35m'
cyan='\033[0;36m'
white='\033[0;37m'

# Complex colors declaration magic
fg_names=("bold" "black" "red" "green" "yellow" "blue" "magenta" "cyan" "white")
fg_vals=(1 30 31 32 33 34 35 36 37)
bg_names=("none" "black" "red" "green" "yellow" "blue" "magenta" "cyan" "white")
bg_vals=(0 40 41 42 43 44 45 46 47)

for ((fg=0; fg < ${#fg_names[*]}; fg++)); do
  for ((bg=0; bg < ${#bg_names[*]}; bg++)); do
    declare "${fg_names[fg]}_on_${bg_names[bg]}"="\\033[${bg_vals[bg]};${fg_vals[fg]}m"
  done
done

# Draws a table of the available coloring options
color_map () {
  # Draw the column titles
  ecn "▼FG   BG►│"
  for ((bg=0; bg < ${#bg_names[*]}; bg++)); do
    printf ' %8s ' "${bg_names[bg]}"
  done
  br
  ec "─────────┼──────────────────────────────────────────────────────────────────────────────────────────"

  for ((fg=0; fg < ${#fg_names[*]}; fg++)); do
    printf '%-8s │' "${fg_names[fg]}"
    for ((bg=0; bg < ${#bg_names[*]}; bg++)); do
      eval color="\$${fg_names[fg]}_on_${bg_names[bg]}"
      ecn " ${color} ******* ${noc}"
    done
    br
  done
}


# Configuration
# ------------------------------------------

# Changing these value to affect the logging functions
SUCCESS_COLOR=${green}
WARN_COLOR=${yellow}
ERROR_COLOR=${red}

# Change this value to define the indentation size
INDENTATION='  '

# Echos
# ------------------------------------------

##
# More consistent echo.
#
ec() {
  IFS=' ' printf "%b\n" "$*"
}

##
# More consistent echo; without the new line.
#
ecn() {
  IFS=' ' printf "%b" "$*"
}

##
# Outputs new line.
# No parameters.
#
br() {
  ec ''
}

##
# Informs that everything goes as planned.
#
success() {
  ec "${SUCCESS_COLOR}$*${noc}"
}

##
# Outputs a menasing message.
#
warn() {
  ec "${WARN_COLOR}$*${noc}"
}

##
# Outputs a scary message.
#
error() {
  >&2 ec "${ERROR_COLOR}ERROR: $*${noc}"
}

##
# Outputs a message and kills the script.
#
fail() {
  error "$@"
  exit 1
}


# Text manipulation
# ------------------------------------------

##
# Reads multiline text from stdin into the specified variable.
#
# Parameters:
#   1: target variable name
#
multiline() {
  IFS= read -r -d '' $1
}

##
# Reads multiline text from stdin and outputs it indented.
#
indent() {
  sed "s/^/${INDENTATION}/"
}


# User input
# ------------------------------------------

##
# Ask user a yes/no question.
# Aborts the script if the answer is no.
#
# Parameters:
#   Interpreted as the question text to be presented to the user.
#
are_you_sure() {
  printf "${WARN_COLOR}$@${noc}"
  read -p " (y/n) " -n 1
  printf "\n"

  if [[ "$REPLY" =~ ^[Yy]$ ]]; then
    return 0
  fi

  return 1
}


#
# ------------------------------------------

##
# Exit if the previous command did not succeed.
#
# Parameters:
#   Interpreted as the failure massage to be presented to the user.
#
assert() {
  if [[ "$?" != "0" ]]; then
    fail "$@"
  fi
}