dotinstall

#!/usr/bin/env bash
################################################################################
# dotinstall - installs dotfiles from a base location (~/.dot, for instance) by
# symlinking them into the user's home directory.
#
# Version 1
# Matthew Malensek <matt@malensek.net>
################################################################################

unset dotdir

shopt -s dotglob #Allow globbing on dotfiles

default_dir="${HOME}/.dot"
override=$(hostname -s)
excludes=(".git" "overrides")

################################################################################

print_usage() {
cat <<EOM
Usage: $(basename "${0}") [-d dot_dir] [-o override]
    -d dot_dir: Specifies the directory where dotfiles are stored.  This
       defaults to ~/.dot, but can also be set by the DOTDIR environment
       variable.
    -o override: Specifies an override configuration to use rather than the
       default, which is based on the current machine hostname
       (DOTDIR/overrides/$(hostname -s)).  This can be used for machine-specific
       configuration, and overrides the "core" configuration (DOTDIR/*).
EOM
}

# Determines if a given file is excluded.
excluded() {
    for exclude in "${excludes[@]}"; do
        if [[ "$(basename "${1}")" == "${exclude}" ]]; then
            return 0
        fi
    done
    return 1
}

# Links dotfiles in ${@} to the current directory.
link_dotfiles() {
    for dot in "${@}/"*; do
        if excluded "${dot}"; then
            continue
        fi
        ln -vs "${dot}"
    done
}

################################################################################

while getopts "d:o:" flag; do
    case ${flag} in
        d) dotdir=${OPTARG} ;;
        o) override=${OPTARG} ;;
        ?) print_usage; exit 1 ;;
    esac
done

if [[ -z "${dotdir}" ]]; then
    # Can we use the default dot directory?
    if [[ -e "${default_dir}" ]]; then
        dotdir="${default_dir}"
    fi

    # How about the DOTDIR environment variable? (overrides the default dir)
    if [[ -n "${DOTDIR}" ]]; then
        dotdir="${DOTDIR}"
    fi

    # Didn't find a dotfile directory.
    if [[ -z "${dotdir}" ]]; then
        echo "Could not locate dotfile directory!"
        exit 1
    fi
fi

if [[ ! -e "${dotdir}" ]]; then
    echo "Dotfile directory could not be found: ${dotdir}"
    exit 1
fi

cd "${HOME}" 2> /dev/null
if [[ ${?} -ne 0 ]]; then
    echo "Could not locate home directory: ${HOME}"
    exit 1
fi

overdir="${dotdir}/overrides/${override}"
if [[ ! -d "${overdir}" ]]; then
    echo "No override configuration found for '${override}.'"
else
    echo "Configuration: ${override}"
    link_dotfiles "${overdir}"
fi

echo "Configuration: core"
link_dotfiles "${dotdir}"