// libnmdc project UserInfo.go
package libnmdc

import (
	"errors"
	"fmt"
	"regexp"
	"strconv"
	"strings"
)

type UserFlag byte

const (
	FLAG_NORMAL          UserFlag = 1
	FLAG_AWAY_1          UserFlag = 2
	FLAG_AWAY_2          UserFlag = 3
	FLAG_SERVER_1        UserFlag = 4
	FLAG_SERVER_2        UserFlag = 5
	FLAG_SERVER_AWAY_1   UserFlag = 6
	FLAG_SERVER_AWAY_2   UserFlag = 7
	FLAG_FIREBALL_1      UserFlag = 8
	FLAG_FIREBALL_2      UserFlag = 9
	FLAG_FIREBALL_AWAY_1 UserFlag = 10
	FLAG_FIREBALL_AWAY_2 UserFlag = 11
)

type ConnectionMode rune

const (
	CONNECTIONMODE_ACTIVE  ConnectionMode = 'A' // 65
	CONNECTIONMODE_PASSIVE ConnectionMode = 'P' // 49
	CONNECTIONMODE_SOCKS5  ConnectionMode = '5' // 53
)

func (this ConnectionMode) String() string {
	switch this {
	case CONNECTIONMODE_ACTIVE:
		return "Active"

	case CONNECTIONMODE_PASSIVE:
		return "Passive"

	case CONNECTIONMODE_SOCKS5:
		return "SOCKS5"

	default:
		return fmt.Sprintf("ConnectionMode(\"%s\")", string(this))
	}
}

// This structure represents a user connected to a hub.
type UserInfo struct {
	Nick             string
	Description      string
	ClientTag        string
	ClientVersion    string
	Email            string
	ShareSize        uint64
	ConnectionMode   ConnectionMode
	Flag             UserFlag
	Slots            uint64
	Speed            string
	HubsUnregistered uint64
	HubsRegistered   uint64
	HubsOperator     uint64
	IsOperator       bool
}

var rx_myinfo *regexp.Regexp
var rx_myinfo_notag *regexp.Regexp

func init() {
	// $ALL <nick> <description>$ $<connection><flag>$<e-mail>$<sharesize>$

	HEAD := `(?ms)^\$ALL ([^ ]+) `
	FOOT := `\$.\$([^$]+)\$([^$]*)\$([0-9]*)\$$`

	rx_myinfo = regexp.MustCompile(HEAD + `([^<]*)<(.+?) V:([^,]+),M:(.),H:([0-9]+)/([0-9]+)/([0-9]+),S:([0-9]+)>` + FOOT)
	rx_myinfo_notag = regexp.MustCompile(HEAD + `([^$]*)` + FOOT) // Fallback for no tag
}

func NewUserInfo(username string) *UserInfo {
	return &UserInfo{
		Nick:             username,
		ConnectionMode:   CONNECTIONMODE_PASSIVE,
		HubsUnregistered: 1,
	}
}

func maybeParse(str string, dest *uint64, default_val uint64) {
	sz, err := strconv.ParseUint(str, 10, 64)
	if err == nil {
		*dest = sz
	} else {
		*dest = default_val
	}
}

func (this *UserInfo) fromMyINFO(protomsg string) error {

	// Normal format (with tag in exact V/M/H/S order)
	matches := rx_myinfo.FindStringSubmatch(protomsg)
	if matches != nil {
		this.Nick = matches[1]
		this.Description = NMDCUnescape(matches[2])
		this.ClientTag = NMDCUnescape(matches[3])
		this.ClientVersion = matches[4]
		this.ConnectionMode = ConnectionMode(matches[4][0])
		maybeParse(matches[6], &this.HubsUnregistered, 0)
		maybeParse(matches[7], &this.HubsRegistered, 0)
		maybeParse(matches[8], &this.HubsOperator, 0)
		maybeParse(matches[9], &this.Slots, 0)
		if len(matches[10]) > 1 {
			this.Speed = matches[10][:len(matches[10])-2]
		} else {
			this.Speed = ""
		}
		this.Flag = UserFlag(matches[10][len(matches[10])-1])
		this.Email = NMDCUnescape(matches[11])
		maybeParse(matches[12], &this.ShareSize, 0)

		return nil
	}

	// No-tag format, used in early connection
	matches = rx_myinfo_notag.FindStringSubmatch(protomsg)
	if matches != nil {
		this.Nick = matches[1]
		this.Description = NMDCUnescape(matches[2])
		this.ClientTag = ""
		this.ClientVersion = "0"
		this.ConnectionMode = CONNECTIONMODE_PASSIVE
		this.HubsUnregistered = 0
		this.HubsRegistered = 0
		this.HubsOperator = 0
		this.Slots = 0

		if len(matches[3]) > 1 {
			this.Speed = matches[3][:len(matches[3])-2]
		} else {
			this.Speed = ""
		}
		this.Flag = UserFlag(matches[3][len(matches[3])-1])
		this.Email = NMDCUnescape(matches[4])
		maybeParse(matches[5], &this.ShareSize, 0)

		return nil
	}

	// Couldn't get anything out of it...
	return errors.New("Malformed MyINFO")
}

// Returns the MyINFO command, WITH leading $MyINFO, and WITHOUT trailing pipe
func (this *UserInfo) toMyINFO() string {
	return fmt.Sprintf(
		"$MyINFO $ALL %s %s<%s V:%s,M:%c,H:%d/%d/%d,S:%d>$ $%s%c$%s$%d$",
		this.Nick,
		this.Description,
		this.ClientTag,
		strings.Replace(this.ClientVersion, ",", "-", -1), // just in case
		this.ConnectionMode,
		this.HubsUnregistered,
		this.HubsRegistered,
		this.HubsOperator,
		this.Slots,
		this.Speed,
		this.Flag,
		this.Email,
		this.ShareSize,
	)
}