// vim:ts=4:sts=4:sw=4:noet:tw=72

package ircd

import (
	"fmt"
	"strings"

	"code.dnix.de/an/irc"
	"code.dnix.de/an/xlog"
)

type commandHook struct {
	HookFn    func(sv *Server, msg *irc.Message)
	MinArgs   int
	NeedTrail bool
	NeedMode  string
}

var svCommandHooks = map[string]commandHook{
	"PRIVMSG": {handleCmdPrivmsg, 1, true, ""},
	"JOIN":    {handleCmdJoin, 1, false, ""},
	"PART":    {handleCmdPart, 1, false, ""},
	"QUIT":    {handleCmdQuit, 0, false, ""},
	"MODE":    {handleCmdMode, 1, false, ""},
	"TOPIC":   {handleCmdTopic, 1, false, ""},
	"KICK":    {handleCmdKick, 2, false, ""},
	"NAMES":   {handleCmdNames, 1, false, ""},
	"WHO":     {handleCmdWho, 1, false, ""},
	"WHOIS":   {handleCmdWhois, 0, false, ""},
	"PING":    {handleCmdPing, 1, false, ""},
	"PONG":    {handleCmdPong, 0, false, ""},
	"REHASH":  {handleCmdRehash, 0, false, "ao"},
	"KILL":    {handleCmdKill, 0, false, "ao"},
	/*
		"LIST":     {handleCmdList, 0, false, false},
		"VERSION":  {handleCmdVersion, 0, false, false},
		"STATS":    {handleCmdStats, 0, false, false},
		"TIME":     {handleCmdTime, 0, false, false},
		"OPER":     {handleCmdOper, 1, false, false},
		"ADMIN":    {handleCmdAdmin, 0, false, false},
		"INFO":     {handleCmdInfo, 0, false, false},
		"WHO":      {handleCmdWho, 0, false, false},
		"WHOWAS":   {handleCmdWhowas, 0, false, false},
		"PONG":     {handleCmdPong, 0, false, false},
		"ERROR":    {handleCmdError, 0, false, false},
		"AWAY":     {handleCmdAway, 0, false, false},
		"RESTART":  {handleCmdRestart, 0, false, false},
		"SUMMON":   {handleCmdSummon, 0, false, false},
		"USERS":    {handleCmdUsers, 0, false, false},
		"USERHOST": {handleCmdUserhost, 0, false, false},
		"ISON":     {handleCmdIson, 0, false, false},
	*/
}

func handleCmdPrivmsg(sv *Server, msg *irc.Message) {
	if strings.HasPrefix(msg.Args[0], "#") {
		clid := strings.ToLower(msg.Pre)
		chid := strings.ToLower(msg.Args[0])
		if sv.channelCheckMode(chid, "m") &&
			!sv.channelCheckPerm(chid, clid, "ohv") {
			sv.sendReply(clid, ERR_CANNOTSENDTOCHAN, chid, "Cannot send to channel")
			return
		}
		if _, exists := sv.chUsers[chid][clid]; !exists {
			sv.sendReply(clid, ERR_CANNOTSENDTOCHAN, chid, "Cannot send to channel")
			return
		}
	}
	sv.sendMsg(msg)
}

func handleCmdJoin(sv *Server, msg *irc.Message) {
	first := false
	clid := strings.ToLower(msg.Pre)
	chid := strings.ToLower(msg.Args[0])
	if !strings.HasPrefix(chid, "#") {
		sv.sendReply(msg.Pre, ERR_NOSUCHCHANNEL, msg.Args[0], "No such channel")
		return
	}
	if _, exists := sv.chUsers[chid]; !exists {
		sv.chUsers[chid] = make(map[string]string)
		sv.chTopics[chid] = ""
		sv.chModes[chid] = make(map[string]bool)
		first = true
	}
	if _, exists := sv.chUsers[chid][clid]; exists {
		return
	}
	sv.chUsers[chid][clid] = ""
	sv.sendMsg(msg)
	// dont proceed further if message was sent by remote origin
	if !sv.localOrigin(msg) {
		return
	}
	sv.cluster.Subscribe(chid, sv.remoteq)
	sv.sendReply(msg.Pre, RPL_TOPIC, msg.Args[0], sv.chTopics[msg.Args[0]])
	sv.channelNames(msg.Pre, msg.Args[0])
	m, isoper := sv.opers[clid]
	if isoper {
		mode := "o " + clid
		sv.chModes[chid][mode] = true
		sv.sendMsg(irc.M(sv.host, "MODE", chid+" +o "+clid, ""))
		if m == "a" {
			sv.sendMsg(irc.M(sv.host, "PRIVMSG", chid, clid+" is a server administrator"))
		}
		if m == "o" {
			sv.sendMsg(irc.M(sv.host, "PRIVMSG", chid, clid+" is a server operator"))
		}
		return
	}
	if first {
		mode := "o " + clid
		sv.chModes[chid][mode] = true
		sv.sendMsg(irc.M(sv.host, "MODE", chid+" +o "+clid, ""))
	}
}

// Handle user parting the channel and delete channel if last user has
// left
func handleCmdPart(sv *Server, msg *irc.Message) {
	clid := strings.ToLower(msg.Pre)
	chid := strings.ToLower(msg.Args[0])
	if _, exists := sv.chUsers[chid]; !exists {
		return
	}
	if _, exists := sv.chUsers[chid][clid]; !exists {
		return
	}
	sv.sendMsg(msg)
	sv.channelRemoveUser(chid, clid)
}

func handleCmdQuit(sv *Server, msg *irc.Message) {

}

func handleCmdMode(sv *Server, msg *irc.Message) {
	if strings.HasPrefix(msg.Args[0], "#") {
		chid := strings.ToLower(msg.Args[0])
		clid := strings.ToLower(msg.Pre)
		if _, exists := sv.chUsers[chid]; !exists {
			return
		}
		if len(msg.Args) < 2 {
			return
		}
		mode := ""
		modeSwitch := msg.Args[1]
		modeTarget := ""
		if len(modeSwitch) < 2 {
			return
		}
		if len(msg.Args) > 2 {
			modeTarget = strings.ToLower(msg.Args[2])
		}
		switch modeSwitch[1] {
		// maybe this can be done more elegant
		case 'o':
			if !sv.channelCheckPerm(chid, clid, "o") {
				goto noPerm
			}
		case 'h':
			if !sv.channelCheckPerm(chid, clid, "o") {
				goto noPerm
			}
		case 'b':
			if !sv.channelCheckPerm(chid, clid, "oh") {
				goto noPerm
			}
		case 'v':
			if !sv.channelCheckPerm(chid, clid, "oh") {
				goto noPerm
			}
		case 'm':
			if !sv.channelCheckPerm(chid, clid, "oh") {
				goto noPerm
			}
		case 't':
			if !sv.channelCheckPerm(chid, clid, "oh") {
				goto noPerm
			}
		default:
			return
		}
		mode = string(modeSwitch[1])
		if modeTarget != "" {
			mode = mode + " " + modeTarget
		}
		if modeSwitch[0] == '+' {
			sv.chModes[chid][mode] = true
		} else {
			delete(sv.chModes[chid], mode)
		}
		sv.sendMsg(msg)
		return
	noPerm:
		sv.sendReply(clid, ERR_CHANOPRIVSNEEDED, chid, "You're not channel operator")
	}
}

func handleCmdTopic(sv *Server, msg *irc.Message) {
	chid := strings.ToLower(msg.Args[0])
	clid := strings.ToLower(msg.Pre)
	if _, exists := sv.chUsers[chid]; !exists {
		sv.sendReply(msg.Pre, ERR_NOSUCHCHANNEL, chid, "No such channel")
	}
	if msg.Trail == "" {
		sv.sendReply(msg.Pre, RPL_TOPIC, chid, sv.chTopics[chid])
	} else {
		if sv.channelCheckMode(chid, "t") &&
			!sv.channelCheckPerm(chid, clid, "oh") {
			sv.sendReply(clid, ERR_CHANOPRIVSNEEDED, chid, "You're not channel operator")
			return
		}
		sv.chTopics[chid] = msg.Trail
		sv.sendMsg(msg)
		//sv.sendReply(msg.Pre, RPL_TOPIC, ch, msg.Trail)
	}
}

func handleCmdKick(sv *Server, msg *irc.Message) {
	chid := strings.ToLower(msg.Args[0])
	clid := strings.ToLower(msg.Pre)
	target := strings.ToLower(msg.Args[1])
	if !sv.channelCheckPerm(chid, clid, "oh") {
		sv.sendReply(clid, ERR_CHANOPRIVSNEEDED, chid, "You're not channel operator")
	}
	sv.sendMsg(msg)
	sv.channelRemoveUser(chid, target)
}

func handleCmdNames(sv *Server, msg *irc.Message) {
	chid := strings.ToLower(msg.Args[0])
	if _, exists := sv.chUsers[chid]; !exists {
		sv.sendReply(msg.Pre, ERR_NOSUCHCHANNEL, chid, "No such channel")
	}
	sv.channelNames(msg.Pre, chid)
}

func handleCmdWho(sv *Server, msg *irc.Message) {
	clid := strings.ToLower(msg.Args[0])
	if _, exists := sv.clients[clid]; exists {
		//	:irc.dnix.de 352 Anydin #northbrigade webuser369 -anon/guest irc.dnix.de webuser36968 H :0 webuser36968
		sv.sendReply(msg.Pre, RPL_WHOREPLY,
			fmt.Sprintf("* %s %s %s %s %s%s", clid, sv.clHosts[clid], sv.host, clid, "H", ""), "0 "+msg.Args[0])
	}
	sv.sendReply(msg.Pre, RPL_ENDOFWHO, clid, "End of /WHO list.")
}

func handleCmdWhois(sv *Server, msg *irc.Message) {
	clid := strings.ToLower(msg.Args[0])
	if _, exists := sv.clients[clid]; !exists {
		sv.sendReply(msg.Pre, ERR_NOSUCHNICK, clid, "No such nick")
		return
	}
	sv.sendReply(msg.Pre, RPL_WHOISUSER, fmt.Sprintf("%s %s %s *", clid, clid, sv.clHosts[clid]), msg.Args[0])
	m, isoper := sv.opers[clid]
	if isoper {
		if m == "a" {
			sv.sendReply(msg.Pre, RPL_WHOISOPERATOR, clid, "is a server administrator")
		}
		if m == "o" {
			sv.sendReply(msg.Pre, RPL_WHOISOPERATOR, clid, "is a server operator")
		}
	}
	sv.sendReply(msg.Pre, RPL_ENDOFWHOIS, "", "End of /WHOIS list")

}

func handleCmdPing(sv *Server, msg *irc.Message) {
	sv.sendReply(msg.Pre, "PONG", msg.Args[0], "")
}

func handleCmdPong(sv *Server, msg *irc.Message) {
}

func handleCmdRehash(sv *Server, msg *irc.Message) {
	sv.loadConfig()
	sv.sendReply(msg.Pre, RPL_REHASHING, "", "Rehashing")
	xlog.Info("Rehashing")
}

func handleCmdKill(sv *Server, msg *irc.Message) {
}