install

#!/bin/sh

usage() {
    cat <<'EOF'
Usage: ./install [rc-file]

Installs these scripts into your shell rc file: adds bin/ and bin/local/
to PATH and sources every file under profile/ and aliases/.

[rc-file] defaults to ~/.zshrc when your shell is zsh, ~/.bashrc when it
is bash, and ~/.profile otherwise. Running the script again is a no-op:
the block is only added once.
EOF
}

case "$1" in
    -h | --help)
        usage
        exit 0
        ;;
    -*)
        echo "Unknown option '$1', see './install --help'" >&2
        exit 1
        ;;
esac

if [ $# -gt 1 ]; then
    echo "Expected at most one rc-file, see './install --help'" >&2
    exit 1
fi

scripts_dir=$(CDPATH='' cd -- "$(dirname -- "$0")" && pwd)

rc=$1
if [ -z "$rc" ]; then
    case "${SHELL##*/}" in
        zsh) rc=$HOME/.zshrc ;;
        bash) rc=$HOME/.bashrc ;;
        *) rc=$HOME/.profile ;;
    esac
fi

marker="# Jor Scripts"
if [ -f "$rc" ] && grep -qF "$marker" "$rc"; then
    echo "Already installed in $rc"
    exit 0
fi

block=$(
    cat <<EOF

$marker
export PATH="$scripts_dir/bin:$scripts_dir/bin/local:\$PATH"
for f in "$scripts_dir"/profile/*; do . "\$f"; done
for f in "$scripts_dir"/aliases/*; do . "\$f"; done
EOF
)

if ! printf '%s\n' "$block" >>"$rc"; then
    echo "Could not write to $rc" >&2
    exit 1
fi

echo "Installed in $rc, restart your shell or run: . $rc"