#!/bin/bash
set -euo pipefail

target=/usr/share/nemo-python/extensions/nemo_terminal.py
patchfile=/usr/share/nemo-terminal-shortcuts/shortcuts.patch
directory=$(dirname "$target")

if [[ ! -f "$target" ]]; then
    echo "Nemo Terminal extension not found." >&2
    exit 1
fi

case "${1:-apply}" in
    apply)
        if patch --dry-run --batch --forward -p0 -d "$directory" \
            < "$patchfile" >/dev/null 2>&1; then
            patch --batch --forward -p0 -d "$directory" < "$patchfile"
        elif patch --dry-run --batch -R -p0 -d "$directory" \
            < "$patchfile" >/dev/null 2>&1; then
            echo "Nemo Terminal shortcuts already patched."
        else
            echo "ERROR: Patch incompatible with installed Nemo Terminal." >&2
            exit 1
        fi
        ;;
    remove)
        if patch --dry-run --batch -R -p0 -d "$directory" \
            < "$patchfile" >/dev/null 2>&1; then
            patch --batch -R -p0 -d "$directory" < "$patchfile"
        elif patch --dry-run --batch --forward -p0 -d "$directory" \
            < "$patchfile" >/dev/null 2>&1; then
            echo "Nemo Terminal already unpatched."
        else
            echo "WARNING: Cannot safely reverse patch." >&2
            exit 1
        fi
        ;;
    *)
        echo "Usage: $0 {apply|remove}" >&2
        exit 2
        ;;
esac