// Copyright (c) 2017 Daniel Oaks <daniel@danieloaks.net>
// released under the MIT license

package irc

import (
	"fmt"
	"strings"
	"time"

	"github.com/DanielOaks/girc-go/ircmsg"
	"github.com/tidwall/buntdb"
)

// csHandler handles the /CS and /CHANSERV commands
func csHandler(server *Server, client *Client, msg ircmsg.IrcMessage) bool {
	server.chanservReceivePrivmsg(client, strings.Join(msg.Params, " "))
	return false
}

func (server *Server) chanservReceiveNotice(client *Client, message string) {
	// do nothing
}

// ChanServNotice sends the client a notice from ChanServ.
func (client *Client) ChanServNotice(text string) {
	client.Send(nil, fmt.Sprintf("ChanServ!services@%s", client.server.name), "NOTICE", client.nick, text)
}

func (server *Server) chanservReceivePrivmsg(client *Client, message string) {
	var params []string
	for _, p := range strings.Split(message, " ") {
		if len(p) > 0 {
			params = append(params, p)
		}
	}
	if len(params) < 1 {
		client.ChanServNotice("You need to run a command")
		//TODO(dan): dump CS help here
		return
	}

	command := strings.ToLower(params[0])
	server.logger.Debug("chanserv", fmt.Sprintf("Client %s ran command %s", client.nick, command))

	if command == "register" {
		if len(params) < 2 {
			client.ChanServNotice("Syntax: REGISTER <channel>")
			return
		}

		if !server.channelRegistrationEnabled {
			client.ChanServNotice("Channel registration is not enabled")
			return
		}

		server.registeredChannelsMutex.Lock()
		defer server.registeredChannelsMutex.Unlock()

		channelName := params[1]
		channelKey, err := CasefoldChannel(channelName)
		if err != nil {
			client.ChanServNotice("Channel name is not valid")
			return
		}

		channelInfo := server.channels.Get(channelKey)
		if channelInfo == nil {
			client.ChanServNotice("You must be an oper on the channel to register it")
			return
		}

		if !channelInfo.ClientIsAtLeast(client, ChannelOperator) {
			client.ChanServNotice("You must be an oper on the channel to register it")
			return
		}

		server.store.Update(func(tx *buntdb.Tx) error {
			currentChan := server.loadChannelNoMutex(tx, channelKey)
			if currentChan != nil {
				client.ChanServNotice("Channel is already registered")
				return nil
			}

			account := client.account
			if account == nil {
				client.ChanServNotice("You must be logged in to register a channel")
				return nil
			}

			chanRegInfo := RegisteredChannel{
				Name:         channelName,
				RegisteredAt: time.Now(),
				Founder:      account.Name,
				Topic:        channelInfo.topic,
				TopicSetBy:   channelInfo.topicSetBy,
				TopicSetTime: channelInfo.topicSetTime,
			}
			server.saveChannelNoMutex(tx, channelKey, chanRegInfo)

			client.ChanServNotice(fmt.Sprintf("Channel %s successfully registered", channelName))

			server.logger.Info("chanserv", fmt.Sprintf("Client %s registered channel %s", client.nick, channelName))

			channelInfo.membersMutex.Lock()
			defer channelInfo.membersMutex.Unlock()

			// give them founder privs
			change := channelInfo.applyModeMemberNoMutex(client, ChannelFounder, Add, client.nickCasefolded)
			if change != nil {
				//TODO(dan): we should change the name of String and make it return a slice here
				//TODO(dan): unify this code with code in modes.go
				args := append([]string{channelName}, strings.Split(change.String(), " ")...)
				for member := range channelInfo.members {
					member.Send(nil, fmt.Sprintf("ChanServ!services@%s", client.server.name), "MODE", args...)
				}
			}

			return nil
		})
	} else {
		client.ChanServNotice("Sorry, I don't know that command")
	}
}