package main

import (
	"bufio"
	"bytes"
	"encoding/binary"
)

const (
	AdminPacketAdminJoin            = 0
	AdminPacketAdminQuit            = 1
	AdminPacketAdminUpdateFrequency = 2
	AdminPacketAdminPoll            = 3
	AdminPacketAdminChat            = 4
	AdminPacketAdminRCon            = 5
	AdminPacketAdminGamescript      = 6
	AdminPacketAdminPing            = 7
	AdminPacketServerFull           = 100
	AdminPacketServerBanned         = 101
	AdminPacketServerError          = 102
	AdminPacketServerProtocol       = 103
	AdminPacketServerWelcome        = 104
	AdminPacketServerNewgame        = 105
	AdminPacketServerShutdown       = 106
	AdminPacketServerDate           = 107
	AdminPacketServerClientJoin     = 108
	AdminPacketServerClientInfo     = 109
	AdminPacketServerClientUpdate   = 110
	AdminPacketServerClientQuit     = 111
	AdminPacketServerClientError    = 112
	AdminPacketServerCompanyNew     = 113
	AdminPacketServerCompanyInfo    = 114
	AdminPacketServerCompanyUpdate  = 115
	AdminPacketServerCompanyRemove  = 116
	AdminPacketServerCompanyEconomy = 117
	AdminPacketServerCompanyStats   = 118
	AdminPacketServerChat           = 119
	AdminPacketServerRCon           = 120
	AdminPacketServerConsole        = 121
	AdminPacketServerCmdNames       = 122
	AdminPacketServerCmdLogging     = 123
	AdminPacketServerGamescript     = 124
	AdminPacketServerRConEnd        = 125
	AdminPacketServerPong           = 126
	InvalidAdminPacket              = 255

	AdminUpdateDate           = 0
	AdminUpdateClientInfo     = 1
	AdminUpdateCompanyInfo    = 2
	AdminUpdateCompanyEconomy = 3
	AdminUpdateCompanyStats   = 4
	AdminUpdateChat           = 5
	AdminUpdateConsole        = 6
	AdminUpdateCmdNames       = 7
	AdminUpdateCmdLogging     = 8
	AdminUpdateGamescript     = 9
	AdminUpdateEnd            = 10

	AdminFrequencyPoll      = 0x01
	AdminFrequencyDaily     = 0x02
	AdminFrequencyWeekly    = 0x04
	AdminFrequencyMonthly   = 0x08
	AdminFrequencyQuarterly = 0x10
	AdminFrequencyAnnually  = 0x20
	AdminFrequencyAutomatic = 0x40
)

type Packet struct {
	PLength uint16
	PType   uint8
}

type PacketAdminJoin struct {
	Packet
	Password   string
	AppName    string
	AppVersion string
}

type PacketAdminServerProtocol struct {
	Packet
	ProtocolVersion    uint8
	FurtherData        bool
	UpdatePacketType   uint16
	FrequenciesAllowed uint16
}

type PacketAdminServerWelcome struct {
	Packet
	ServerName     string
	OpenTTDVersion string
	Dedicated      bool
	MapName        string
	MapSeed        uint32
	MapLandscape   uint8
	MapStartDate   uint32
	MapX           uint16
	MapY           uint16
}

type PacketAdminUpdateFrequency struct {
	Packet
	UpdateType      uint16
	UpdateFrequency uint16
}

func (p *PacketAdminJoin) Bytes() []byte {
	buf := new(bytes.Buffer)
	p.PLength = uint16(len(p.Password) + len(p.AppName) + len(p.AppVersion) + 6)

	binary.Write(buf, binary.LittleEndian, p.PLength)
	binary.Write(buf, binary.LittleEndian, p.PType)
	buf.WriteString(p.Password)
	buf.WriteByte(0)
	buf.WriteString(p.AppName)
	buf.WriteByte(0)
	buf.WriteString(p.AppVersion)
	buf.WriteByte(0)

	return buf.Bytes()
}

func (p *PacketAdminUpdateFrequency) Bytes() []byte {
	buf := new(bytes.Buffer)
	p.PLength = 7
	binary.Write(buf, binary.LittleEndian, p.PLength)
	binary.Write(buf, binary.LittleEndian, p.PType)
	binary.Write(buf, binary.LittleEndian, p.UpdateType)
	binary.Write(buf, binary.LittleEndian, p.UpdateFrequency)

	return buf.Bytes()
}

func (p *PacketAdminServerWelcome) Read(b []byte) {
	r := bufio.NewReader(bytes.NewReader(b))
	r.Discard(3)
	p.ServerName, _ = r.ReadString(0)
	p.OpenTTDVersion, _ = r.ReadString(0)
	c, _ := r.ReadByte()
	if c > 0 {
		p.Dedicated = true
	} else {
		p.Dedicated = false
	}
	p.MapName, _ = r.ReadString(0)
	bs := make([]byte, 13)
	_, _ = r.Read(bs)
	p.MapSeed = binary.LittleEndian.Uint32(bs[0:])
	r.Discard(4)
	c, _ = r.ReadByte()
	p.MapLandscape = uint8(c)
	p.MapStartDate = binary.LittleEndian.Uint32(bs[5:])
	p.MapX = binary.LittleEndian.Uint16(bs[9:])
	p.MapY = binary.LittleEndian.Uint16(bs[11:])
}

func (p *PacketAdminServerProtocol) Read(b []byte) {
	r := bufio.NewReader(bytes.NewReader(b))
	r.Discard(3)
	c, _ := r.ReadByte()
	p.ProtocolVersion = uint8(c)
	c, _ = r.ReadByte()
	if c > 0 {
		p.FurtherData = true
	} else {
		p.FurtherData = false
	}
	bs := make([]byte, 13)
	_, _ = r.Read(bs)
	p.UpdatePacketType = binary.LittleEndian.Uint16(bs[0:])
	p.FrequenciesAllowed = binary.LittleEndian.Uint16(bs[2:])
}

func readPacket(p Packet, b []byte) {

}