#!/bin/bash
# lib/bbr.sh - BBR TCP congestion control management

# Include guard
[[ -n "${__X_UI_BBR_INCLUDED:-}" ]] && return 0
__X_UI_BBR_INCLUDED=1

# Source dependencies
source "${LIB_DIR}/common.sh"

bbr_menu() {
    echo -e "${green}\t1.${plain} Enable BBR"
    echo -e "${green}\t2.${plain} Disable BBR"
    echo -e "${green}\t0.${plain} Back to Main Menu"
    read -rp "Choose an option: " choice
    case "$choice" in
    0)
        show_menu
        ;;
    1)
        enable_bbr
        bbr_menu
        ;;
    2)
        disable_bbr
        bbr_menu
        ;;
    *)
        echo -e "${red}Invalid option. Please select a valid number.${plain}\n"
        bbr_menu
        ;;
    esac
}

disable_bbr() {

    if ! grep -q "net.core.default_qdisc=fq" /etc/sysctl.conf || ! grep -q "net.ipv4.tcp_congestion_control=bbr" /etc/sysctl.conf; then
        echo -e "${yellow}BBR is not currently enabled.${plain}"
        before_show_menu
    fi

    # Replace BBR with CUBIC configurations
    sed -i 's/net.core.default_qdisc=fq/net.core.default_qdisc=pfifo_fast/' /etc/sysctl.conf
    sed -i 's/net.ipv4.tcp_congestion_control=bbr/net.ipv4.tcp_congestion_control=cubic/' /etc/sysctl.conf

    # Apply changes
    sysctl -p

    # Verify that BBR is replaced with CUBIC
    if [[ $(sysctl net.ipv4.tcp_congestion_control | awk '{print $3}') == "cubic" ]]; then
        echo -e "${green}BBR has been replaced with CUBIC successfully.${plain}"
    else
        echo -e "${red}Failed to replace BBR with CUBIC. Please check your system configuration.${plain}"
    fi
}

enable_bbr() {
    if grep -q "net.core.default_qdisc=fq" /etc/sysctl.conf && grep -q "net.ipv4.tcp_congestion_control=bbr" /etc/sysctl.conf; then
        echo -e "${green}BBR is already enabled!${plain}"
        before_show_menu
    fi

    # Enable BBR
    echo "net.core.default_qdisc=fq" | tee -a /etc/sysctl.conf
    echo "net.ipv4.tcp_congestion_control=bbr" | tee -a /etc/sysctl.conf

    # Apply changes
    sysctl -p

    # Verify that BBR is enabled
    if [[ $(sysctl net.ipv4.tcp_congestion_control | awk '{print $3}') == "bbr" ]]; then
        echo -e "${green}BBR has been enabled successfully.${plain}"
    else
        echo -e "${red}Failed to enable BBR. Please check your system configuration.${plain}"
    fi
}