#!/usr/bin/env zsh
# SPDX-FileCopyrightText: © 2026 David Parsons
# SPDX-License-Identifier: MIT

# tanoe.sh - Manage gdmf.apple.com in /etc/hosts
# Usage: ./tanoe [on|off|status]

# Enable debug mode if DEBUG environment variable is set to any non-empty value
[[ -n "$DEBUG" ]] && set -x

HOSTS_FILE="/etc/hosts"
HOST_ENTRY="127.0.0.1 gdmf.apple.com"
COMMENT="# Managed by tanoe"

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

# Function to check if entry exists
check_status() {
    if grep -q "^127\.0\.0\.1[[:space:]]*gdmf\.apple\.com" "$HOSTS_FILE" 2>/dev/null; then
        return 0  # Entry exists
    else
        return 1  # Entry does not exist
    fi
}

# Function to display current status
show_status() {
    if check_status; then
        echo "${GREEN}✓ Status: ENABLED${NC}"
        echo "  Entry '${HOST_ENTRY}' is present in ${HOSTS_FILE}"
    else
        echo "${YELLOW}✗ Status: DISABLED${NC}"
        echo "  Entry '${HOST_ENTRY}' is not present in ${HOSTS_FILE}"
    fi
}


# Function to check auto updates
auto_update_off() {
    auto=$(defaults read /Library/Preferences/com.apple.SoftwareUpdate AutomaticDownload)
    if [[ $auto -eq 1 ]]; then
        echo "${YELLOW}macOS automatic updates are enabled.${NC}"
        echo -e "${YELLOW}Do you want to disable automatic software updates? (y/n):${NC} \c"
        read -r response
        if [[ "$response" =~ ^[Yy]$ ]]; then
            open "x-apple.systempreferences:com.apple.Software-Update-Settings.extension"
            exit
        else
            echo "${RED}Tanoe will not run until auto updates are disabled${NC}"
            exit
        fi
    else
        return
    fi
}

# Function to add entry
add_entry() {
    if check_status; then
        echo "${YELLOW}Entry already exists in ${HOSTS_FILE}${NC}"
        return 0
    fi
    
    echo "Adding entry to ${HOSTS_FILE}..."
    
    # Create backup in current directory
    BACKUP_FILE="./hosts.backup.$(date +%Y%m%d_%H%M%S)"
    sudo cp "$HOSTS_FILE" "$BACKUP_FILE"
    echo "Backup created: $BACKUP_FILE"
    
    # Check if file ends with newline, if not add one
    if [ -n "$(tail -c 1 "$HOSTS_FILE")" ]; then
        echo "" | sudo tee -a "$HOSTS_FILE" > /dev/null
    fi
    
    # Add entry with comment on same line to avoid orphaned comments
    echo "$HOST_ENTRY  $COMMENT" | sudo tee -a "$HOSTS_FILE" > /dev/null
    
    if check_status; then
        echo "${GREEN}✓ Successfully added entry${NC}"
        # Flush DNS cache
        echo "Flushing DNS cache..."
        sudo dscacheutil -flushcache
        sudo killall -HUP mDNSResponder 2>/dev/null
        echo "Updating available updates..."
        softwareupdate --list
        return 0
    else
        echo "${RED}✗ Failed to add entry${NC}"
        return 1
    fi
}

# Function to remove entry
remove_entry() {
    if ! check_status; then
        echo "${YELLOW}Entry does not exist in ${HOSTS_FILE}${NC}"
        return 0
    fi
    
    echo "Removing entry from ${HOSTS_FILE}..."
    
    # Create backup
    sudo cp "$HOSTS_FILE" "${HOSTS_FILE}.backup.$(date +%Y%m%d_%H%M%S)"
    
    # Remove entry (handles both inline comment and separate comment line formats)
    sudo sed -i.tmp '/^127\.0\.0\.1[[:space:]]*gdmf\.apple\.com/d' "$HOSTS_FILE"
    # Also remove standalone comment line if it exists
    sudo sed -i.tmp '/^# Managed by hosts-manager\.zsh$/d' "$HOSTS_FILE"
    sudo rm -f "${HOSTS_FILE}.tmp"
    
    if ! check_status; then
        echo "${GREEN}✓ Successfully removed entry${NC}"
        # Flush DNS cache
        echo "Flushing DNS cache..."
        sudo dscacheutil -flushcache
        sudo killall -HUP mDNSResponder 2>/dev/null
        echo "Updating available updates..."
        softwareupdate --list
        return 0
    else
        echo "${RED}✗ Failed to remove entry${NC}"
        return 1
    fi
}

# Function to show usage
show_usage() {
    echo "Usage: $0 [on|off|status]"
    echo ""
    echo "Commands:"
    echo "  on      - Add '${HOST_ENTRY}' to ${HOSTS_FILE}"
    echo "  off     - Remove '${HOST_ENTRY}' from ${HOSTS_FILE}"
    echo "  status  - Show current status of the entry"
    echo ""
    echo "Note: This script requires sudo privileges to modify ${HOSTS_FILE}"
}

# Main script logic
auto_update_off
case "${1:-}" in
    on)
        add_entry
        ;;
    off)
        remove_entry
        ;;
    status)
        show_status
        ;;
    *)
        show_usage
        if [[ -n "${1:-}" ]]; then
            echo ""
            echo "${RED}Error: Unknown command '${1}'${NC}"
            exit 1
        fi
        exit 0
        ;;
esac