#!/usr/bin/env bash

set -euo pipefail

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'

print_info() {
    echo -e "${BLUE}📘${NC} $1"
}

print_success() {
    echo -e "${GREEN}✅${NC} $1"
}

print_error() {
    echo -e "${RED}❌${NC} $1"
}

print_warning() {
    echo -e "${YELLOW}⚡${NC} $1"
}

print_info "Available generations:"
if [[ "$EUID" -ne 0 ]]; then
    sudo nix-env --profile /nix/var/nix/profiles/system --list-generations
else
    nix-env --profile /nix/var/nix/profiles/system --list-generations
fi

echo -n "Enter generation number to rollback to: "
read -r GEN_NUM

if [[ -z "$GEN_NUM" ]]; then
    print_error "No generation number provided"
    exit 1
fi

print_warning "Rolling back to generation $GEN_NUM..."
if [[ "$EUID" -ne 0 ]]; then
    sudo nix-env --profile /nix/var/nix/profiles/system --switch-generation "$GEN_NUM" && \
    sudo /nix/var/nix/profiles/system/bin/switch-to-configuration switch
else
    nix-env --profile /nix/var/nix/profiles/system --switch-generation "$GEN_NUM" && \
    /nix/var/nix/profiles/system/bin/switch-to-configuration switch
fi

print_success "Rollback to generation $GEN_NUM complete"