#!/bin/bash
# install.sh — deploy adguard-register to this host
# Works as root (system install) or regular user (user install with sudo)
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

if [ "$(id -u)" -eq 0 ]; then
    # Root: system-wide install
    BIN_PATH="/usr/local/bin/adguard-register"
    SERVICE_PATH="/etc/systemd/system/adguard-register.service"
    SERVICE_TYPE="system"
else
    # Non-root: user install, try sudo for systemd, fall back to cron
    BIN_PATH="${HOME}/.local/bin/adguard-register"
    mkdir -p "${HOME}/.local/bin"
    SERVICE_TYPE="user"

    # Check if we can sudo
    if sudo -n true 2>/dev/null; then
        HAS_SUDO=1
    else
        HAS_SUDO=0
    fi
fi

echo "=== Installing adguard-register (${SERVICE_TYPE}) ==="

# Copy script
if [ "$(id -u)" -eq 0 ]; then
    cp "${SCRIPT_DIR}/adguard-register.sh" "${BIN_PATH}"
else
    # May need sudo for the copy if dir is protected
    cp "${SCRIPT_DIR}/adguard-register.sh" "${BIN_PATH}" 2>/dev/null || \
        sudo cp "${SCRIPT_DIR}/adguard-register.sh" "${BIN_PATH}"
fi
chmod +x "${BIN_PATH}"
echo "→ Installed ${BIN_PATH}"

# Install service
if [ "${SERVICE_TYPE}" = "system" ]; then
    # System service (root)
    cat > "${SERVICE_PATH}" << 'SERVICEOF'
[Unit]
Description=Register host with AdGuard Home DNS
After=network-online.target
Wants=network-online.target

[Service]
Type=oneshot
ExecStart=/usr/local/bin/adguard-register
RemainAfterExit=yes

[Install]
WantedBy=multi-user.target
SERVICEOF
    echo "→ Created ${SERVICE_PATH}"
    systemctl daemon-reload
    systemctl enable adguard-register.service
    echo "→ Enabled adguard-register.service"
    systemctl start adguard-register.service 2>&1 || true
    echo "→ Registration result:"
    systemctl status adguard-register.service --no-pager --lines=5 2>&1 || true

elif [ "${HAS_SUDO}" -eq 1 ]; then
    # User with sudo — install system service via sudo
    sudo tee "${SERVICE_PATH:-/etc/systemd/system/adguard-register.service}" > /dev/null << 'SERVICEOF'
[Unit]
Description=Register host with AdGuard Home DNS
After=network-online.target
Wants=network-online.target

[Service]
Type=oneshot
ExecStart=/usr/local/bin/adguard-register
RemainAfterExit=yes

[Install]
WantedBy=multi-user.target
SERVICEOF
    sudo cp "${BIN_PATH}" /usr/local/bin/adguard-register
    sudo chmod +x /usr/local/bin/adguard-register
    BIN_PATH="/usr/local/bin/adguard-register"
    sudo systemctl daemon-reload
    sudo systemctl enable adguard-register.service
    echo "→ Enabled adguard-register.service (system via sudo)"
    sudo systemctl start adguard-register.service 2>&1 || true
    sudo systemctl status adguard-register.service --no-pager --lines=5 2>&1 || true

else
    # User without sudo — try user systemd, then crontab, then just run once
    INSTALLED=0

    # Attempt 1: user systemd service (works if lingering is enabled)
    if command -v systemctl &>/dev/null && systemctl --user daemon-reload 2>/dev/null; then
        mkdir -p ~/.config/systemd/user
        cat > ~/.config/systemd/user/adguard-register.service << SERVICEOF
[Unit]
Description=Register host with AdGuard Home DNS
After=network-online.target

[Service]
Type=oneshot
ExecStart=${BIN_PATH}
RemainAfterExit=yes

[Install]
WantedBy=default.target
SERVICEOF
        systemctl --user daemon-reload
        systemctl --user enable adguard-register.service 2>/dev/null && {
            echo "→ Enabled user systemd service"
            systemctl --user start adguard-register.service 2>&1 || true
            INSTALLED=1
        }
    fi

    # Attempt 2: crontab
    if [ "$INSTALLED" -eq 0 ] && command -v crontab &>/dev/null; then
        (crontab -l 2>/dev/null | grep -v 'adguard-register' || true) > /tmp/adguard-crontab
        echo "@reboot ${BIN_PATH}" >> /tmp/adguard-crontab
        crontab /tmp/adguard-crontab 2>/dev/null && {
            echo "→ Added @reboot cron job"
            INSTALLED=1
        }
        rm -f /tmp/adguard-crontab
    fi

    # Run once now regardless
    echo "→ Running registration..."
    bash "${BIN_PATH}" 2>&1 || true

    if [ "$INSTALLED" -eq 0 ]; then
        echo ""
        echo "⚠️  Could not set up auto-start (no sudo, no systemd --user, no crontab)."
        echo "   The script is installed at ${BIN_PATH}"
        echo "   Run it manually or set up auto-start yourself."
    fi
fi

echo ""
echo "=== Installation complete ==="
echo "The agent will auto-run on every boot."
echo "To manually re-register: ${BIN_PATH}"