#!/usr/bin/env bash

# toggle_apple_updates.sh
# Toggles Apple OTA update domains in /etc/hosts between blocked and unblocked.

HOSTS_FILE="/etc/hosts"

APPLE_DOMAINS=(
    "swscan.apple.com"
    "swdownload.apple.com"
    "swcdn.apple.com"
    "swdist.apple.com"
    "appldnld.apple.com"
    "mesu.apple.com"
    "gdmf.apple.com"
)

BLOCK_IP="0.0.0.0"
SECTION_COMMENT="# Block OTA"

# ── Colours ──────────────────────────────────────────────────────────────────
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
CYAN='\033[0;36m'
BOLD='\033[1m'
RESET='\033[0m'

# ── Banner ────────────────────────────────────────────────────────────────────
echo ""
echo -e "${BOLD}+----------------------------------------------+${RESET}"
echo -e "${BOLD}|      Apple OTA Update Toggle Utility         |${RESET}"
echo -e "${BOLD}+----------------------------------------------+${RESET}"
echo ""

# ── Root warning ──────────────────────────────────────────────────────────────
echo -e "${YELLOW}⚠  WARNING: This script modifies ${HOSTS_FILE}.${RESET}"
echo -e "${YELLOW}   Root (administrator) privileges are required.${RESET}"
echo ""

# ── Authenticate via sudo ─────────────────────────────────────────────────────
echo -e "${CYAN}Please enter your password to continue:${RESET}"
sudo -v 2>/dev/null
if [[ $? -ne 0 ]]; then
    echo -e "${RED}✖  Authentication failed or was cancelled. Exiting.${RESET}"
    exit 1
fi
echo ""

# ── Detect current state ──────────────────────────────────────────────────────
# Check if the first domain is currently blocked (present and uncommented)
FIRST_DOMAIN="${APPLE_DOMAINS[0]}"
if sudo grep -qE "^${BLOCK_IP}[[:space:]]+${FIRST_DOMAIN}" "${HOSTS_FILE}"; then
    CURRENT_STATE="blocked"
else
    CURRENT_STATE="unblocked"
fi

CURRENT_STATE_UPPER=$(echo "${CURRENT_STATE}" | tr '[:lower:]' '[:upper:]')
echo -e "  Current state: ${BOLD}Apple updates are ${CURRENT_STATE_UPPER}${RESET}"
echo ""

# ── Toggle ────────────────────────────────────────────────────────────────────
if [[ "${CURRENT_STATE}" == "blocked" ]]; then
    # ── UNBLOCK: comment out the block section ────────────────────────────────
    echo -e "${CYAN}→ Unblocking Apple update domains...${RESET}"

    # Comment out the section header and each domain line
    sudo sed -i '.bak' "s|^${SECTION_COMMENT}$|#${SECTION_COMMENT}|g" "${HOSTS_FILE}"
    for domain in "${APPLE_DOMAINS[@]}"; do
        sudo sed -i '.bak' "s|^${BLOCK_IP}[[:space:]][[:space:]]*${domain}|# ${BLOCK_IP} ${domain}|g" "${HOSTS_FILE}"
    done

    NEW_STATE="UNBLOCKED"
    STATE_COLOR="${GREEN}"
    STATE_MSG="Apple software updates are now ${GREEN}${BOLD}ENABLED${RESET}."
    STATE_DETAIL="Your Mac can reach Apple's update servers normally."

else
    # ── BLOCK: uncomment or add the block section ─────────────────────────────
    echo -e "${CYAN}→ Blocking Apple update domains...${RESET}"

    # Uncomment lines that were previously commented out by this script
    sudo sed -i '.bak' "s|^#${SECTION_COMMENT}$|${SECTION_COMMENT}|g" "${HOSTS_FILE}"
    for domain in "${APPLE_DOMAINS[@]}"; do
        # If the commented-out version exists, uncomment it
        if sudo grep -qE "^#[[:space:]]*${BLOCK_IP}[[:space:]]+${domain}" "${HOSTS_FILE}"; then
            sudo sed -i '.bak' "s|^#[[:space:]]*${BLOCK_IP}[[:space:]][[:space:]]*${domain}|${BLOCK_IP} ${domain}|g" "${HOSTS_FILE}"
        # If the domain isn't present at all, append the block section
        elif ! sudo grep -qE "${domain}" "${HOSTS_FILE}"; then
            # Append section header if it doesn't exist
            if ! sudo grep -q "^${SECTION_COMMENT}$" "${HOSTS_FILE}"; then
                echo "" | sudo tee -a "${HOSTS_FILE}" > /dev/null
                echo "${SECTION_COMMENT}" | sudo tee -a "${HOSTS_FILE}" > /dev/null
            fi
            echo "${BLOCK_IP} ${domain}" | sudo tee -a "${HOSTS_FILE}" > /dev/null
        fi
    done

    NEW_STATE="BLOCKED"
    STATE_COLOR="${RED}"
    STATE_MSG="Apple software updates are now ${RED}${BOLD}BLOCKED${RESET}."
    STATE_DETAIL="Your Mac cannot reach Apple's update servers."
fi

# ── Result ────────────────────────────────────────────────────────────────────
echo ""
echo -e "${BOLD}+----------------------------------------------+${RESET}"
printf "${BOLD}|${RESET}  New state: ${STATE_COLOR}%-33s${RESET}${BOLD}|${RESET}\n" "${NEW_STATE}"
echo -e "${BOLD}+----------------------------------------------+${RESET}"
echo ""
echo -e "  ${STATE_MSG}"
echo -e "  ${STATE_DETAIL}"
echo ""
echo -e "  Domains affected:"
for domain in "${APPLE_DOMAINS[@]}"; do
    echo -e "    ${STATE_COLOR}•${RESET} ${domain}"
done
echo ""
echo -e "  A backup of your previous hosts file was saved as:"
echo -e "  ${BOLD}${HOSTS_FILE}.bak${RESET}"
echo ""