#!/bin/sh
# SecuBox WireGuard Control CLI
# Manages WireGuard interfaces and uplink failover
# Copyright (C) 2026 CyberMind.fr

. /lib/functions.sh

UPLINK_LIB="/usr/lib/wireguard-dashboard/uplink.sh"
UPLINK_CONFIG="wireguard_uplink"
RUNTIME_STATE="/var/run/wireguard-uplinks.json"

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

log_info() { echo -e "${GREEN}[INFO]${NC} $*"; }
log_warn() { echo -e "${YELLOW}[WARN]${NC} $*"; }
log_error() { echo -e "${RED}[ERROR]${NC} $*" >&2; }

# Load uplink library if available
load_uplink_lib() {
    if [ -f "$UPLINK_LIB" ]; then
        . "$UPLINK_LIB"
        return 0
    fi
    return 1
}

# UCI helpers
uci_get() { uci -q get ${UPLINK_CONFIG}.$1; }
uci_set() { uci set ${UPLINK_CONFIG}.$1="$2" && uci commit ${UPLINK_CONFIG}; }

usage() {
    cat <<'EOF'
SecuBox WireGuard Control CLI

Usage: wgctl <command> [options]

Interface Commands:
  status              Show all WireGuard interfaces
  show <iface>        Show details for interface
  up <iface>          Bring interface up
  down <iface>        Bring interface down

Uplink Commands (Multi-WAN Failover):
  uplink list         List available uplink peers from mesh
  uplink add <peer>   Add peer as backup uplink
  uplink remove <peer> Remove peer uplink
  uplink status       Show uplink failover status
  uplink test <peer>  Test connectivity through peer
  uplink failover <enable|disable>
                      Enable/disable automatic failover
  uplink priority <peer> <weight>
                      Set peer priority (lower = less preferred)
  uplink offer        Advertise this node as uplink provider
  uplink withdraw     Stop advertising as uplink provider

Examples:
  wgctl status
  wgctl uplink list
  wgctl uplink add nodeA
  wgctl uplink failover enable

Configuration:
  /etc/config/wireguard_uplink

EOF
}

# ============================================================
# Interface Commands
# ============================================================

cmd_status() {
    if ! command -v wg >/dev/null 2>&1; then
        log_error "wireguard-tools not installed"
        exit 1
    fi

    local interfaces=$(wg show interfaces 2>/dev/null)

    if [ -z "$interfaces" ]; then
        echo "No WireGuard interfaces configured"
        return 0
    fi

    echo "WireGuard Interfaces"
    echo "===================="
    echo ""

    for iface in $interfaces; do
        local pubkey=$(wg show "$iface" public-key 2>/dev/null)
        local port=$(wg show "$iface" listen-port 2>/dev/null)
        local peers=$(wg show "$iface" peers 2>/dev/null | wc -l)
        local state="down"
        ip link show "$iface" 2>/dev/null | grep -q "UP" && state="up"

        local ip=$(ip -4 addr show "$iface" 2>/dev/null | grep -oE 'inet [0-9.]+' | cut -d' ' -f2)

        printf "${BLUE}%s${NC}\n" "$iface"
        printf "  State:       %s\n" "$([ "$state" = "up" ] && echo -e "${GREEN}UP${NC}" || echo -e "${RED}DOWN${NC}")"
        printf "  Address:     %s\n" "${ip:-N/A}"
        printf "  Listen Port: %s\n" "${port:-N/A}"
        printf "  Public Key:  %s\n" "${pubkey:0:20}..."
        printf "  Peers:       %d\n" "$peers"

        # Check if this is an uplink interface
        local is_uplink=$(uci -q get network.${iface}.secubox_uplink)
        if [ "$is_uplink" = "1" ]; then
            local peer_id=$(uci -q get network.${iface}.secubox_peer_id)
            printf "  ${YELLOW}Uplink:${NC}      %s\n" "${peer_id:-yes}"
        fi
        echo ""
    done

    # Show uplink summary if enabled
    local uplink_enabled=$(uci_get uplink.enabled)
    if [ "$uplink_enabled" = "1" ]; then
        echo "Uplink Failover: ${GREEN}ENABLED${NC}"
        local active_uplinks=$(cat "$RUNTIME_STATE" 2>/dev/null | jsonfilter -e '@.active_uplinks' 2>/dev/null || echo "0")
        echo "Active Uplinks:  $active_uplinks"
    fi
}

cmd_show() {
    local iface="$1"

    if [ -z "$iface" ]; then
        log_error "Usage: wgctl show <interface>"
        exit 1
    fi

    if ! wg show "$iface" >/dev/null 2>&1; then
        log_error "Interface $iface not found"
        exit 1
    fi

    wg show "$iface"
}

cmd_up() {
    local iface="$1"

    if [ -z "$iface" ]; then
        log_error "Usage: wgctl up <interface>"
        exit 1
    fi

    log_info "Bringing up $iface..."
    ifup "$iface" 2>/dev/null || ip link set "$iface" up
    log_info "Interface $iface is up"
}

cmd_down() {
    local iface="$1"

    if [ -z "$iface" ]; then
        log_error "Usage: wgctl down <interface>"
        exit 1
    fi

    log_info "Bringing down $iface..."
    ifdown "$iface" 2>/dev/null || ip link set "$iface" down
    log_info "Interface $iface is down"
}

# ============================================================
# Uplink Commands
# ============================================================

uplink_list() {
    load_uplink_lib || {
        log_error "Uplink library not found"
        exit 1
    }

    echo "Available Uplink Peers"
    echo "======================"
    echo ""

    # Get peers from gossip/P2P discovery
    local peers_file="/var/run/p2p-uplink-offers.json"

    if [ ! -f "$peers_file" ]; then
        # Try to fetch from P2P gossip
        if command -v p2pctl >/dev/null 2>&1; then
            p2pctl gossip get uplink_offers > "$peers_file" 2>/dev/null
        fi
    fi

    if [ -f "$peers_file" ] && [ -s "$peers_file" ]; then
        # Parse JSON offers
        local count=0
        jsonfilter -i "$peers_file" -e '@[*]' 2>/dev/null | while read -r offer; do
            local peer_id=$(echo "$offer" | jsonfilter -e '@.peer_id' 2>/dev/null)
            local bandwidth=$(echo "$offer" | jsonfilter -e '@.capabilities.bandwidth_mbps' 2>/dev/null)
            local latency=$(echo "$offer" | jsonfilter -e '@.capabilities.latency_ms' 2>/dev/null)
            local wan_type=$(echo "$offer" | jsonfilter -e '@.capabilities.wan_type' 2>/dev/null)
            local available=$(echo "$offer" | jsonfilter -e '@.capabilities.available' 2>/dev/null)

            [ -z "$peer_id" ] && continue
            count=$((count + 1))

            local status="${GREEN}available${NC}"
            [ "$available" != "true" ] && status="${RED}unavailable${NC}"

            printf "%2d. ${BLUE}%s${NC}\n" "$count" "$peer_id"
            printf "    Status:    %b\n" "$status"
            printf "    Bandwidth: %s Mbps\n" "${bandwidth:-?}"
            printf "    Latency:   %s ms\n" "${latency:-?}"
            printf "    WAN Type:  %s\n" "${wan_type:-unknown}"
            echo ""
        done
    else
        echo "No uplink offers discovered yet."
        echo ""
        echo "Peers advertise uplink capability via gossip protocol."
        echo "Make sure P2P mesh is connected and peers have enabled uplink sharing."
    fi

    # Also show locally configured uplinks
    echo ""
    echo "Configured Uplinks"
    echo "=================="

    local found=0
    config_load network
    config_foreach _show_uplink_iface interface

    [ $found -eq 0 ] && echo "No uplinks configured. Use: wgctl uplink add <peer_id>"
}

_show_uplink_iface() {
    local cfg="$1"
    local is_uplink
    config_get is_uplink "$cfg" secubox_uplink "0"

    [ "$is_uplink" != "1" ] && return

    local peer_id proto
    config_get peer_id "$cfg" secubox_peer_id
    config_get proto "$cfg" proto

    [ "$proto" != "wireguard" ] && return

    found=1
    printf "  - %s (peer: %s)\n" "$cfg" "${peer_id:-unknown}"
}

uplink_add() {
    local peer_id="$1"

    if [ -z "$peer_id" ]; then
        log_error "Usage: wgctl uplink add <peer_id>"
        exit 1
    fi

    load_uplink_lib || {
        log_error "Uplink library not found"
        exit 1
    }

    log_info "Adding uplink peer: $peer_id"

    # Get peer info from gossip
    local peer_info
    peer_info=$(get_peer_uplink_offer "$peer_id")

    if [ -z "$peer_info" ]; then
        log_error "Peer $peer_id not found in uplink offers"
        log_info "Make sure the peer is advertising uplink capability"
        exit 1
    fi

    # Extract endpoint info
    local endpoint_host=$(echo "$peer_info" | jsonfilter -e '@.endpoint.host' 2>/dev/null)
    local endpoint_port=$(echo "$peer_info" | jsonfilter -e '@.endpoint.port' 2>/dev/null)
    local public_key=$(echo "$peer_info" | jsonfilter -e '@.endpoint.public_key' 2>/dev/null)

    if [ -z "$public_key" ]; then
        log_error "Could not get public key for peer $peer_id"
        exit 1
    fi

    # Create WireGuard interface for uplink
    local iface_name="wg_uplink_${peer_id}"

    log_info "Creating interface $iface_name..."

    # Generate private key if needed
    local priv_key=$(wg genkey)
    local pub_key=$(echo "$priv_key" | wg pubkey)

    # Create network interface
    uci set network.${iface_name}=interface
    uci set network.${iface_name}.proto='wireguard'
    uci set network.${iface_name}.private_key="$priv_key"
    uci add_list network.${iface_name}.addresses='10.99.0.2/24'
    uci set network.${iface_name}.secubox_uplink='1'
    uci set network.${iface_name}.secubox_peer_id="$peer_id"

    # Add peer config
    local peer_section=$(uci add network wireguard_${iface_name})
    uci set network.${peer_section}.public_key="$public_key"
    uci set network.${peer_section}.endpoint_host="$endpoint_host"
    uci set network.${peer_section}.endpoint_port="${endpoint_port:-51820}"
    uci add_list network.${peer_section}.allowed_ips='0.0.0.0/0'
    uci add_list network.${peer_section}.allowed_ips='::/0'
    uci set network.${peer_section}.persistent_keepalive='25'
    uci set network.${peer_section}.route_allowed_ips='0'

    uci commit network

    # Add to mwan3 if enabled
    local auto_failover=$(uci_get uplink.auto_failover)
    if [ "$auto_failover" = "1" ]; then
        add_uplink_to_mwan3 "$iface_name" "$peer_id"
    fi

    # Bring up interface
    ifup "$iface_name"

    log_info "Uplink $peer_id added successfully"
    log_info "Your public key (share with peer): $pub_key"
}

uplink_remove() {
    local peer_id="$1"

    if [ -z "$peer_id" ]; then
        log_error "Usage: wgctl uplink remove <peer_id>"
        exit 1
    fi

    local iface_name="wg_uplink_${peer_id}"

    log_info "Removing uplink peer: $peer_id"

    # Bring down interface
    ifdown "$iface_name" 2>/dev/null

    # Remove from mwan3
    remove_uplink_from_mwan3 "$iface_name"

    # Remove network config
    uci delete network.${iface_name} 2>/dev/null

    # Remove peer configs
    local idx=0
    while uci -q get network.@wireguard_${iface_name}[$idx] >/dev/null 2>&1; do
        uci delete network.@wireguard_${iface_name}[$idx]
    done

    uci commit network

    log_info "Uplink $peer_id removed"
}

uplink_status() {
    load_uplink_lib || {
        log_error "Uplink library not found"
        exit 1
    }

    echo "Uplink Failover Status"
    echo "======================"
    echo ""

    local enabled=$(uci_get uplink.enabled)
    local auto_failover=$(uci_get uplink.auto_failover)
    local check_interval=$(uci_get uplink.check_interval)

    printf "Enabled:        %s\n" "$([ "$enabled" = "1" ] && echo -e "${GREEN}yes${NC}" || echo -e "${RED}no${NC}")"
    printf "Auto Failover:  %s\n" "$([ "$auto_failover" = "1" ] && echo -e "${GREEN}yes${NC}" || echo -e "${RED}no${NC}")"
    printf "Check Interval: %ss\n" "${check_interval:-30}"
    echo ""

    # Show primary WAN status
    echo "Primary WAN:"
    local wan_status=$(ping -c 1 -W 2 8.8.8.8 >/dev/null 2>&1 && echo "up" || echo "down")
    printf "  Status: %s\n" "$([ "$wan_status" = "up" ] && echo -e "${GREEN}UP${NC}" || echo -e "${RED}DOWN${NC}")"
    echo ""

    # Show uplink interfaces
    echo "Uplink Interfaces:"
    config_load network

    local uplink_count=0
    for iface in $(uci show network 2>/dev/null | grep 'secubox_uplink=.1' | cut -d'.' -f2); do
        uplink_count=$((uplink_count + 1))
        local peer_id=$(uci -q get network.${iface}.secubox_peer_id)
        local state="down"
        ip link show "$iface" 2>/dev/null | grep -q "UP" && state="up"

        # Test connectivity through this uplink
        local reachable="no"
        if [ "$state" = "up" ]; then
            # Ping through specific interface
            local gw=$(ip route show dev "$iface" 2>/dev/null | grep default | awk '{print $3}')
            if [ -n "$gw" ]; then
                ping -c 1 -W 2 -I "$iface" 8.8.8.8 >/dev/null 2>&1 && reachable="yes"
            fi
        fi

        printf "  %s (%s):\n" "$iface" "${peer_id:-unknown}"
        printf "    State:     %s\n" "$([ "$state" = "up" ] && echo -e "${GREEN}UP${NC}" || echo -e "${RED}DOWN${NC}")"
        printf "    Reachable: %s\n" "$([ "$reachable" = "yes" ] && echo -e "${GREEN}yes${NC}" || echo -e "${RED}no${NC}")"
    done

    [ $uplink_count -eq 0 ] && echo "  No uplinks configured"
    echo ""

    # Show current routing
    if command -v mwan3 >/dev/null 2>&1; then
        echo "mwan3 Status:"
        mwan3 status 2>/dev/null | head -20
    fi
}

uplink_test() {
    local peer_id="$1"

    if [ -z "$peer_id" ]; then
        log_error "Usage: wgctl uplink test <peer_id>"
        exit 1
    fi

    local iface_name="wg_uplink_${peer_id}"

    log_info "Testing connectivity through $peer_id..."

    # Check interface exists
    if ! ip link show "$iface_name" >/dev/null 2>&1; then
        log_error "Interface $iface_name not found"
        exit 1
    fi

    # Ping through uplink
    echo "Pinging 8.8.8.8 through $iface_name..."
    if ping -c 3 -W 5 -I "$iface_name" 8.8.8.8; then
        echo ""
        log_info "Uplink $peer_id is ${GREEN}WORKING${NC}"
    else
        echo ""
        log_error "Uplink $peer_id is ${RED}NOT REACHABLE${NC}"
        exit 1
    fi
}

uplink_failover() {
    local action="$1"

    case "$action" in
        enable)
            log_info "Enabling uplink failover..."
            uci_set uplink.enabled '1'
            uci_set uplink.auto_failover '1'

            # Setup mwan3 for all configured uplinks
            setup_mwan3_failover

            log_info "Uplink failover enabled"
            ;;
        disable)
            log_info "Disabling uplink failover..."
            uci_set uplink.enabled '0'
            uci_set uplink.auto_failover '0'

            # Remove mwan3 config for uplinks
            cleanup_mwan3_failover

            log_info "Uplink failover disabled"
            ;;
        *)
            log_error "Usage: wgctl uplink failover <enable|disable>"
            exit 1
            ;;
    esac
}

uplink_priority() {
    local peer_id="$1"
    local weight="$2"

    if [ -z "$peer_id" ] || [ -z "$weight" ]; then
        log_error "Usage: wgctl uplink priority <peer_id> <weight>"
        log_info "Lower weight = lower priority (backup)"
        exit 1
    fi

    local iface_name="wg_uplink_${peer_id}"

    # Update mwan3 member weight
    local member="${iface_name}_member"
    uci set mwan3.${member}.weight="$weight"
    uci commit mwan3

    # Reload mwan3
    /etc/init.d/mwan3 reload 2>/dev/null

    log_info "Priority for $peer_id set to weight $weight"
}

uplink_offer() {
    load_uplink_lib || {
        log_error "Uplink library not found"
        exit 1
    }

    log_info "Advertising this node as uplink provider..."

    advertise_uplink_offer

    log_info "Uplink offer advertised via gossip"
}

uplink_withdraw() {
    load_uplink_lib || {
        log_error "Uplink library not found"
        exit 1
    }

    log_info "Withdrawing uplink offer..."

    withdraw_uplink_offer

    log_info "Uplink offer withdrawn"
}

# ============================================================
# mwan3 Integration Helpers
# ============================================================

add_uplink_to_mwan3() {
    local iface="$1"
    local peer_id="$2"

    # Check if mwan3 is available
    [ ! -f /etc/config/mwan3 ] && return

    log_info "Adding $iface to mwan3..."

    # Add interface
    uci set mwan3.${iface}=interface
    uci set mwan3.${iface}.enabled='1'
    uci set mwan3.${iface}.family='ipv4'
    uci set mwan3.${iface}.reliability='1'
    uci set mwan3.${iface}.track_method='ping'
    uci add_list mwan3.${iface}.track_ip='8.8.8.8'

    # Add member with low weight (backup)
    local member="${iface}_member"
    uci set mwan3.${member}=member
    uci set mwan3.${member}.interface="$iface"
    uci set mwan3.${member}.weight='10'
    uci set mwan3.${member}.metric='10'

    # Add to failover policy
    uci add_list mwan3.failover_policy.use_member="$member"

    uci commit mwan3
    /etc/init.d/mwan3 reload 2>/dev/null
}

remove_uplink_from_mwan3() {
    local iface="$1"

    [ ! -f /etc/config/mwan3 ] && return

    local member="${iface}_member"

    uci delete mwan3.${iface} 2>/dev/null
    uci delete mwan3.${member} 2>/dev/null
    uci del_list mwan3.failover_policy.use_member="$member" 2>/dev/null

    uci commit mwan3
    /etc/init.d/mwan3 reload 2>/dev/null
}

setup_mwan3_failover() {
    [ ! -f /etc/config/mwan3 ] && return

    # Ensure failover policy exists
    if ! uci -q get mwan3.failover_policy >/dev/null; then
        uci set mwan3.failover_policy=policy
        uci add_list mwan3.failover_policy.use_member='wan_member'
    fi

    # Add all uplink interfaces
    config_load network
    for iface in $(uci show network 2>/dev/null | grep 'secubox_uplink=.1' | cut -d'.' -f2); do
        local peer_id=$(uci -q get network.${iface}.secubox_peer_id)
        add_uplink_to_mwan3 "$iface" "$peer_id"
    done
}

cleanup_mwan3_failover() {
    [ ! -f /etc/config/mwan3 ] && return

    # Remove all uplink interfaces from mwan3
    for iface in $(uci show network 2>/dev/null | grep 'secubox_uplink=.1' | cut -d'.' -f2); do
        remove_uplink_from_mwan3 "$iface"
    done
}

# ============================================================
# Main
# ============================================================

case "${1:-}" in
    status)
        shift; cmd_status "$@" ;;
    show)
        shift; cmd_show "$@" ;;
    up)
        shift; cmd_up "$@" ;;
    down)
        shift; cmd_down "$@" ;;
    uplink)
        shift
        case "${1:-}" in
            list)     shift; uplink_list "$@" ;;
            add)      shift; uplink_add "$@" ;;
            remove)   shift; uplink_remove "$@" ;;
            status)   shift; uplink_status "$@" ;;
            test)     shift; uplink_test "$@" ;;
            failover) shift; uplink_failover "$@" ;;
            priority) shift; uplink_priority "$@" ;;
            offer)    shift; uplink_offer "$@" ;;
            withdraw) shift; uplink_withdraw "$@" ;;
            *)        log_error "Unknown uplink command: $1"; usage; exit 1 ;;
        esac
        ;;
    -h|--help|help)
        usage ;;
    *)
        usage ;;
esac