#!/bin/bash
# Name: ipfn
# Version: 1.0.5
# Date: 2026-01-22
# Description: Added asterisk highlight for new handles and forced delete (-df).

# sudo権限チェック
if [ "$(id -u)" -ne 0 ]; then
    exec sudo "$0" "$@"
fi

TABLE_NAME="ipf_wrapper"
QUIET=false
PROTO="tcp"
FORCE_DELETE=false

# --- 初期化 ---
init_nft() {
    nft add table inet ${TABLE_NAME} 2>/dev/null
    nft add chain inet ${TABLE_NAME} prerouting { type nat hook prerouting priority -100 \; } 2>/dev/null
    nft add chain inet ${TABLE_NAME} output { type nat hook output priority -100 \; } 2>/dev/null
    nft add chain inet ${TABLE_NAME} postrouting { type nat hook postrouting priority 100 \; } 2>/dev/null
    nft add chain inet ${TABLE_NAME} forward { type filter hook forward priority 0 \; policy accept \; } 2>/dev/null
}

# --- ルール表示 (アスタリスク強調対応) ---
list_rules() {
    local highlight_uuid=$1
    init_nft
    echo "Forwarding Rules (ipfn):"
    printf "%-10s %-6s %-20s %-20s %-10s\n" "HANDLE" "PROTO" "LOCAL" "TARGET" "UUID"
    echo "-----------------------------------------------------------------------------------"
    
    nft -a list chain inet ${TABLE_NAME} prerouting | grep "dnat" | while read -r line; do
        handle=$(echo "$line" | grep -o 'handle [0-9]*' | awk '{print $2}')
        proto=$(echo "$line" | grep -q "udp" && echo "udp" || echo "tcp")
        target=$(echo "$line" | grep -oE '[0-9.]*:[0-9]+' | head -n 1)
        lport=$(echo "$line" | grep -o 'dport [0-9]*' | awk '{print $2}')
        full_uuid=$(echo "$line" | grep -o 'ipf-id:[a-z0-9-]*' | cut -d':' -f2)
        short_uuid="${full_uuid:0:8}"

        if [[ -n "$highlight_uuid" && "$full_uuid" == "$highlight_uuid" ]]; then
            # 新規ルールは HANDLE の前に * を付け、シアン太字で表示
            printf "\e[1;36m*%-9s %-6s %-20s %-20s %-10s\e[0m\n" "$handle" "$proto" ":$lport" "$target" "$short_uuid"
        else
            printf "%-10s %-6s %-20s %-20s %-10s\n" "$handle" "$proto" ":$lport" "$target" "$short_uuid"
        fi
    done
}

# --- ルール追加 ---
add_rule() {
    init_nft
    local port_ip_port=$1
    local local_port=$(echo "$port_ip_port" | cut -d':' -f1)
    local target_ip=$(echo "$port_ip_port" | cut -d':' -f2)
    local target_port=$(echo "$port_ip_port" | cut -d':' -f3)

    local raw_uuid=$(cat /proc/sys/kernel/random/uuid)
    local uuid="ipf-id:$raw_uuid"
    local comment="comment \"$uuid\""
    local family="ip"
    [[ "$target_ip" =~ : ]] && family="ip6"

    nft add rule inet ${TABLE_NAME} prerouting "$PROTO" dport "$local_port" dnat $family to "$target_ip:$target_port" "$comment"
    nft add rule inet ${TABLE_NAME} output "$PROTO" dport "$local_port" dnat $family to "$target_ip:$target_port" "$comment"
    nft add rule inet ${TABLE_NAME} forward iifname "lo" accept "$comment"
    nft add rule inet ${TABLE_NAME} forward $family daddr "$target_ip" "$PROTO" dport "$target_port" ct state new,established,related accept "$comment"
    nft add rule inet ${TABLE_NAME} forward $family saddr "$target_ip" "$PROTO" sport "$target_port" ct state established,related accept "$comment"
    nft add rule inet ${TABLE_NAME} postrouting $family daddr "$target_ip" "$PROTO" dport "$target_port" masquerade "$comment"

    if [[ $QUIET == false ]]; then
        echo "ipfn: Rule added."
        echo ""
        list_rules "$raw_uuid"
    fi
}

# --- ルール削除 (強制削除フラグ対応) ---
delete_rule() {
    init_nft
    local handle=$1
    local rule_info=$(nft -a list chain inet ${TABLE_NAME} prerouting | grep "handle $handle")
    if [[ -z "$rule_info" ]]; then
        echo "Error: Rule handle $handle not found."
        exit 1
    fi

    local uuid=$(echo "$rule_info" | grep -o 'ipf-id:[a-z0-9-]*' | head -n 1)
    local lport=$(echo "$rule_info" | grep -o 'dport [0-9]*' | awk '{print $2}')
    local target=$(echo "$rule_info" | grep -oE '[0-9.]*:[0-9]+' | head -n 1)

    local do_delete=false
    if [[ "$FORCE_DELETE" == true ]]; then
        do_delete=true
    else
        echo "About to delete rule group:"
        echo "  Handle: $handle"
        echo "  Local:  :$lport"
        echo "  Target: $target"
        echo -n "Are you sure? (y/N): "
        read -r confirm
        [[ "$confirm" =~ ^[yY]$ ]] && do_delete=true
    fi

    if [[ "$do_delete" == true ]]; then
        for chain in prerouting output forward postrouting; do
            nft -a list chain inet ${TABLE_NAME} "$chain" | grep "$uuid" | grep -o 'handle [0-9]*' | awk '{print $2}' | while read -r h; do
                nft delete rule inet ${TABLE_NAME} "$chain" handle "$h"
            done
        done
        echo "ipfn: Rule handle $handle deleted."
        echo ""
        list_rules
    else
        echo "Aborted."
    fi
}

# --- メイン処理 ---
# 引数の前処理 (強制削除フラグの検出)
TEMP_ARGS=()
while [[ $# -gt 0 ]]; do
    case "$1" in
        -df) FORCE_DELETE=true; TEMP_ARGS+=("-d") ;;
        -f)  # 削除コンテキストでのみ強制フラグとして動作
             FORCE_DELETE=true ;; 
        *)   TEMP_ARGS+=("$1") ;;
    esac
    shift
done
set -- "${TEMP_ARGS[@]}"

while [[ $# -gt 0 ]]; do
    case "$1" in
        -L|-l) list_rules; exit 0 ;;
        -d)    [[ -z "$2" ]] && { echo "Error: Handle required."; exit 1; }
               delete_rule "$2"; exit 0 ;;
        -t)    # 疎通確認ロジック (ver 1.0.4と同様)
               local handle=$2
               local rule_line=$(nft -a list chain inet ${TABLE_NAME} prerouting | grep "handle $handle")
               if [[ -z "$rule_line" ]]; then echo "Error: Handle $handle not found."; exit 1; fi
               local lp=$(echo "$rule_line" | grep -o 'dport [0-9]*' | awk '{print $2}')
               echo "Testing :$lp..."
               nc -z -v -w 3 127.0.0.1 "$lp" 2>&1 | grep -E "succeeded|connected" && echo -e "\e[32mSuccess\e[0m" || echo -e "\e[31mFailed\e[0m"
               exit 0 ;;
        -p)    PROTO="$2"; shift 2 ;;
        -q)    QUIET=true; shift ;;
        -f_sys) # 内部用: 以前の -f (sysctl) は -f_sys またはメインループ外で処理
            sysctl -w net.ipv4.ip_forward=1 >/dev/null
            sysctl -w net.ipv4.conf.all.route_localnet=1 >/dev/null
            echo "Kernel parameters updated."; exit 0 ;;
        -v)    nft list table inet ${TABLE_NAME}; exit 0 ;;
        *)     break ;;
    esac
    shift
done

# 初期設定 (-f 単体で実行された場合などの互換性維持)
if [[ "$FORCE_DELETE" == true && $# -eq 0 ]]; then
    # -f 単体ならカーネル設定を行う
    sysctl -w net.ipv4.ip_forward=1
    sysctl -w net.ipv4.conf.all.route_localnet=1
    exit 0
fi

if [[ -n "$1" ]]; then
    add_rule "$1"
else
    echo "Usage: ipfn [PORT:IP:PORT | -L | -d HANDLE | -df HANDLE | -t HANDLE]"
fi