mark

#!/bin/bash

read -r -d '' usage << EOM
mark [-d] [mark_name [mark_destination]]
mark -l

Set a symlink bookmark at \$HOME/.mk/mark_name that directs to the current directory or mark_destination.

DESCRIPTION
    Bookmarks are stored as symlinks (shortcuts) in \$HOME/.mk, and can be accessed like usual:
        mv ~/.mk/mark_name1/somefile ~/path/to/destination
        cd -P ~/.mk/mark_name

    Use -P flag when cd into symlink to resolve dot-dot. Otherwise, your pwd will look like
    ~/.mk/mark_name instead of ~/some/directory/mark_name, and when you try to go back with
    cd .. you will end up in the bookmark directory. You can set an alias in bashrc for
    convenience
        alias cd="cd -P"

    Bookmarks are stored as symlinks, so moving, deleting, etc. will only apply to the bookmark.
    
    When not given any arguments, set default mark \$mk/a -> cwd

OPTIONS
    -d
        Delete bookmark with mark_name instead of normal functionality
    -l
        List all bookmarks available

CONFIGURATIONS
    bashrc:
        export MK="\$HOME/.mk"  # avoid typing out ~/.mk
        alias cd="cd -P"    # Automatically resolves symlinks with cd

    You can also bookmark the ~/.mk folder in most GUI file explorers for easy access with GUI
    as well. On Ubuntu, this is done by dragging the folder onto the sidebar.
EOM

# Note: use `-P` flag when `cd` into symlink to resolve dot-dot. Otherwise, your pwd will look
# like ~/.mk/mark_name instead of ~/some/directory/mark_name, and when you try to go back with
# `cd ..` you will end up in the bookmark directory

# Tip: you can bookmark the `.mk` folder in your file explorer to access it easily with GUI too.
# on Ubuntu, you do this by dragging the directory onto the sidebar.
#
# You can also export your mark folder as an environmental variable in bashrc:
#   export MK="$HOME/.mk"
# This way, you can access your bookmarks with `$MK/mark_name`

# Enum indicating mode of command
# 0: new bookmark; 1: delete bookmark
readonly MODE_NEW=0;
readonly MODE_DEL=1;
readonly MODE_HELP=2;
readonly MODE_LIST=3;
mode=$MODE_NEW

while getopts "dhl" opt; do
    case $opt in
	d)
        mode=$MODE_DEL
        shift 1
	    ;;
    h)
        mode=$MODE_HELP
        shift 1
	    ;;
    l)
        mode=$MODE_LIST
        shift 1
        ;;
	\?)
	    echo "Invalid option: -$OPTARG" >&2
        echo "Try the -h flag for usage" >&2
        exit 1
	    ;;
    esac
done


# Set bookmark directory where bookmarks (symlinks) are stored
mark_folder="$HOME/.mk"
if [[ ! -d "$mark_folder" ]]; then
    mkdir "$mark_folder"
fi

mark_path="$mark_folder/${1:-a}"
mark_dest="$(pwd)/$2"
case $mode in
    "$MODE_HELP" ) # Print usage
        echo "$usage" >&2
        ;;
    "$MODE_NEW" ) # Create new bookmark
        # TODO: Bookmark Description <26-01-23, xydxydxyd1> #

        # Validate input
        if [[ "$#" -gt 2 ]]; then
            echo "Illegal number of parameters" >&2
            echo "Try the -h flag for usage" >&2
            exit 1
        fi

        if [[ ! -e $mark_dest ]]; then
            echo "$mark_dest does not exist. Aborting..."
            return
        fi

        # Option for overriding existing bookmark
        if [[ (-L $mark_path) && ($mark_path != "$mark_folder/a") ]]; then
            read -r -p 'Mark already exists. Override (y/n)? ' yn
            if [[ "$yn" != 'y' ]]; then
                echo 'Aborting...'
                exit 1
            fi
        fi
        rm -f "$mark_path"
        ln -s "$mark_dest" "$mark_path"
        echo "Symlink created: $mark_path --> $mark_dest"
        ;;
    "$MODE_DEL" ) # Delete bookmark
        # Validate input
        if [[ "$#" -ne 1 ]]; then
            echo "Illegal number of parameters" >&2
            echo "Try the -h flag for usage" >&2
            exit 1
        fi

        if [[ ! -h "$mark_path" ]]; then
            echo "$mark_path does not exist"
            exit 1
        fi

        read -r -p "Remove $mark_path? " yn
        if [[ "$yn" != 'y' ]]; then
            echo "Aborting..."
        fi
        rm -f "$mark_path"
        ;;
    "$MODE_LIST" ) # List all bookmarks
        ls -l "$mark_folder"
        ;;
esac

exit 0