#!/bin/bash

#

# cheatsheet_viewer.sh

#

# Copyright (C) 2025, Branko Majic <branko@majic.rs>

#

# This program is free software: you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program.  If not, see <http://www.gnu.org/licenses/>.

#

# Treat unset variables as errors.

set -u

PROGRAM="cheatsheet_viewer.sh"

VERSION="0.0.1"

function usage() {

    cat <<EOF

$PROGRAM $VERSION, simple utility for viewing image cheatsheets

Usage:

  $PROGRAM [OPTIONS] list

EOF

}

function short_help() {

    cat <<EOF

$(usage)

For more details see $PROGRAM -h.

EOF

}

function long_help() {

    cat <<EOF

$(usage)

$PROGRAM is a simple utility for viewing image cheatsheets with

support for multiple profiles.

All configuration is stored under user's own home directory at:

  - ~/.config/cheatsheet_viewer/

Individual profiles are stored as sub-directories, with each

sub-directory representing an individual profile that can be

activated. Base directory for profiles is:

  - ~/.config/cheatsheet_viewer/profiles/

Multiple commands are provided for working with the profiles and

displaying the cheatsheets.

list

  Lists the available profiles.

$PROGRAM accepts the following options:

    -q

        Quiet mode.

    -d

        Enable debug mode.

    -v

        Show script version and licensing information.

    -h

        Show full help.

Please report bugs and send feature requests to <branko@majic.rs>.

EOF

}

function version() {

    cat <<EOF

$PROGRAM, version $VERSION

+-----------------------------------------------------------------------+

| Copyright (C) 2025, Branko Majic <branko@majic.rs>                    |

|                                                                       |

| This program is free software: you can redistribute it and/or modify  |

| it under the terms of the GNU General Public License as published by  |

| the Free Software Foundation, either version 3 of the License, or     |

| (at your option) any later version.                                   |

|                                                                       |

| This program is distributed in the hope that it will be useful,       |

| but WITHOUT ANY WARRANTY; without even the implied warranty of        |

| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         |

| GNU General Public License for more details.                          |

|                                                                       |

| You should have received a copy of the GNU General Public License     |

| along with this program.  If not, see <http://www.gnu.org/licenses/>. |

+-----------------------------------------------------------------------+

EOF

}

# Commands

# ========

#

# Lists available profiles.

#

# Arguments:

#

#   $1 (config_dir)

#     Base directory under which all configuration files are stored.

#

# Returns:

#   0 on success, 1 otherwise.

#

function command_list() {

    local config_dir="$1"

    local profiles_dir="$config_dir/profiles"

    shopt -s nullglob

    local profiles=("$profiles_dir"/*)

    shopt -u nullglob

    if (( ${#profiles[@]} == 0 )); then

        echo "No profiles defined under $profiles_dir"

        return 0

    fi

    echo "Available profiles:"

    echo

    for profile in "${profiles[@]}"; do

        echo "  - $(basename "$profile")"

    done

}

# Set-up colours for message printing if we're not piping and terminal is

# capable of outputting the colors.

_COLOR_TERMINAL=$(tput colors 2>&1)

if [[ -t 1 ]] && (( _COLOR_TERMINAL > 0 )); then

    _TEXT_BOLD=$(tput bold)

    _TEXT_WHITE=$(tput setaf 7)

    _TEXT_BLUE=$(tput setaf 6)

    _TEXT_GREEN=$(tput setaf 2)

    _TEXT_YELLOW=$(tput setaf 3)

    _TEXT_RED=$(tput setaf 1)

    _TEXT_RESET=$(tput sgr0)

else

    _TEXT_BOLD=""

    _TEXT_WHITE=""

    _TEXT_BLUE=""

    _TEXT_GREEN=""

    _TEXT_YELLOW=""

    _TEXT_RED=""

    _TEXT_RESET=""

fi

# Set-up functions for printing coloured messages.

function debug() {

    if [[ $DEBUG != 0 ]]; then

        echo "${_TEXT_BOLD}${_TEXT_BLUE}[DEBUG]${_TEXT_RESET}" "$@"

    fi

}

function info() {

    if [[ $QUIET == 0 ]]; then

        echo "${_TEXT_BOLD}${_TEXT_WHITE}[INFO] ${_TEXT_RESET}" "$@"

    fi

}

function success() {

    if [[ $QUIET == 0 ]]; then

        echo "${_TEXT_BOLD}${_TEXT_GREEN}[OK]   ${_TEXT_RESET}" "$@"

    fi

}

function warning() {

    echo "${_TEXT_BOLD}${_TEXT_YELLOW}[WARN] ${_TEXT_RESET}" "$@" >&2

}

function error() {

    echo "${_TEXT_BOLD}${_TEXT_RED}[ERROR]${_TEXT_RESET}" "$@" >&2

}

# Define error codes.

SUCCESS=0

ERROR_ARGUMENTS=1

# Disable debug and quiet modes by default.

DEBUG=0

QUIET=0

# Default paths, directories etc.

CONFIG_DIR="$HOME/.config/cheatsheet_viewer"

# If no arguments were given, just show usage help.

if [[ -z ${1-} ]]; then

    short_help

    exit "$SUCCESS"

fi

# Parse the arguments

while getopts "qdvh" opt; do

    case "$opt" in

        q) QUIET=1;;

        d) DEBUG=1;;

        v) version

           exit "$SUCCESS";;

        h) long_help

           exit "$SUCCESS";;

        *) short_help

           exit "$ERROR_ARGUMENTS";;

    esac

done

i=$OPTIND

shift $(( i-1 ))

# Quiet and debug are mutually exclusive.

if [[ $QUIET != 0 && $DEBUG != 0 ]]; then

    error "Quiet and debug options are mutually exclusive."

    exit "$ERROR_ARGUMENTS"

fi

COMMAND="${1-}"

shift

if [[ $COMMAND == list ]]; then

    command_list "$CONFIG_DIR"

else

    error "Unsupported command: $COMMAND"

    exit "$ERROR_ARGUMENTS"

fi