package describer

import (
    "encoding/hex"
    "eruhs/core/parser"
    "fmt"
)

type IPv4Describer struct {
    IPv4 *parser.IPv4
}

func (i *IPv4Describer) GetHeader() []byte {
    return i.IPv4.Header
}

func (i *IPv4Describer) GetDetailDescribe() Describe {
    optionDescribe := make([]map[string]string, 0)
    for _, option := range i.IPv4.Options {
        optionDescribe = append(optionDescribe, map[string]string{
            "类型": fmt.Sprintf("%d", option.OptionType),
            "长度": fmt.Sprintf("%d", option.OptionLength),
            "数据": hex.EncodeToString(option.OptionData),
        })
    }

    protoName := ""
    switch i.IPv4.Protocol {
    case parser.IPv4ProtoICMP:
        protoName = "ICMP"
    case parser.IPv4ProtoIGMP:
        protoName = "IGMP"
    case parser.IPv4ProtoTCP:
        protoName = "TCP"
    case parser.IPv4ProtoUDP:
        protoName = "UDP"
    case parser.IPv4ProtoENCAP:
        protoName = "ENCAP"
    case parser.IPv4ProtoOSPF:
        protoName = "OSPF"
    case parser.IPv4ProtoSCTP:
        protoName = "SCTP"
    }

    return Describe{
        1:  {"版本", fmt.Sprintf("%d", i.IPv4.Version)},
        2:  {"首部长度", fmt.Sprintf("%d", i.IPv4.IHL)},
        3:  {"区分服务", fmt.Sprintf("%d", i.IPv4.DS)},
        4:  {"总长", fmt.Sprintf("%d", i.IPv4.TotalLength)},
        5:  {"标识符", fmt.Sprintf("%d", i.IPv4.Id)},
        6:  {"标志", fmt.Sprintf("%d", i.IPv4.Flags)},
        7:  {"分片偏移", fmt.Sprintf("%d", i.IPv4.FragOffset)},
        8:  {"存活时间", fmt.Sprintf("%d", i.IPv4.TTL)},
        9:  {"应用层协议", protoName},
        10: {"首部校验和", fmt.Sprintf("%d", i.IPv4.Checksum)},
        11: {"源地址", i.IPv4.SrcIP.String()},
        12: {"目的地址", i.IPv4.DstIP.String()},
        13: {"选项字段", fmt.Sprintf("%+v", optionDescribe)},
        14: {"填充", fmt.Sprintf("%d Byte", len(i.IPv4.Padding))},
    }
}