hig

#!/bin/bash
################################################################################
# Name:        hig
# Date:        2024-11-12
# Author:      Amosnimos
# Description: Highlight specified words in piped or file input, with customizable background or foreground colors, without altering the original text.
################################################################################

# ▌ ▌▜▘▞▀▖
# ▙▄▌▐ ▌▄▖
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# Function to print text with highlighting
highlight_text() {
    local search="$1"
    local input="$2"
    local color="$3"
    local invert_fg="$4"

    # Define color codes
    declare -A colors=(
        [red]="\033[41m"       # Background Red
        [green]="\033[42m"     # Background Green
        [yellow]="\033[43m"    # Background Yellow
        [blue]="\033[44m"      # Background Blue
        [purple]="\033[45m"    # Background Purple
        [cyan]="\033[46m"      # Background Cyan
        [white]="\033[47m"     # Background White
        [black]="\033[40m"     # Background Black
        [text_black]="\033[30m" # Text Black
        [text_white]="\033[37m" # Text White
        [reset]="\033[0m"      # Reset
    )

    # Set default highlight colors
    local highlight_bg="${colors[$color]:-${colors[yellow]}}"
    local default_fg_color="${colors[text_white]}"
    local default_bg="${colors[black]}"

    # If invert flag is set, use color for text and keep background black
    local highlight="${highlight_bg}${colors[text_black]}"
    if [[ "$invert_fg" == "true" ]]; then
        highlight="${colors[black]}${colors[${color}]}"
    fi

    # Process each line from input
    while IFS= read -r line; do
        if [[ -z "$search" ]]; then
            # Print without highlights if no search term
            echo -e "${default_bg}${default_fg_color}${line}${colors[reset]}"
        else
            # Highlight with background or foreground based on invert flag
            echo -e "${line//${search}/${highlight}${search}${colors[reset]}}"
        fi
    done <<< "$input"
}

# Default values
search_string=""
highlight_color="yellow"
invert_fg="false"
file_input=""

# Function to display help
print_help() {
    cat << EOF
Usage: hig -s <search_term> [-f <filename>] [-c <color>] [-i] [-h]

Options:
  -s, --search <search_term>   Word to highlight in the input text.
  -f, --file <filename>        Optional: specify file input instead of pipe.
  -c, --color <color>          Optional: background color for highlighting (default: yellow).
  -i, --invert                 Optional: invert highlight to color text instead of background.
  -h, --help                   Display this help message.

Description:
  Hig highlights all occurrences of <search_term> in piped or file input.
  By default, highlighted text is black on a yellow background; use -c to change
  background color, or -i to invert and color text instead.

Examples:
  echo "hello world" | hig -s world           # Highlight "world" with default colors
  echo "hello world" | hig -s world -c red    # Highlight "world" with red background
  echo "hello world" | hig -s world -i        # Highlight "world" with yellow text

EOF
}

# Parsing options
while [[ "$#" -gt 0 ]]; do
    case "$1" in
        -h|--help) print_help; exit 0;;
        -s|--search) search_string="$2"; shift 2;;
        -c|--color) highlight_color="$2"; shift 2;;
        -f|--file) file_input="$2"; shift 2;;
        -i|--invert) invert_fg="true"; shift;;
        *) echo "Unknown option: $1" >&2; print_help; exit 1;;
    esac
done

# Check if input is from a pipe or file
if [[ -n "$file_input" ]]; then
    input="$(<"$file_input")"
elif [[ ! -t 0 ]]; then
    input="$(cat)"
else
    exit 0  # Exit if neither file nor pipe input
fi

# Run the highlighting function
highlight_text "$search_string" "$input" "$highlight_color" "$invert_fg"