From 610fc5068d662990bbab07256742316a554d7f56 Mon Sep 17 00:00:00 2001
From: Shivaram Lingamneni <slingamn@cs.stanford.edu>
Date: Mon, 26 Oct 2020 23:08:05 -0400
Subject: [PATCH] refactor DEOP

DEOP is now pure syntactic sugar for /mode #channel -o nick,
the change is attributed to the originating user and not to ChanServ.
---
 irc/chanserv.go | 59 +++++++++++++++++++++++++------------------------
 1 file changed, 30 insertions(+), 29 deletions(-)

diff --git a/irc/chanserv.go b/irc/chanserv.go
index cf9eb6fb..c221eb44 100644
--- a/irc/chanserv.go
+++ b/irc/chanserv.go
@@ -42,10 +42,9 @@ this command if you're the founder of the channel.`,
 
 DEOP removes the given nickname, or yourself, the channel admin. You can only use
 this command if you're the founder of the channel.`,
-			helpShort:    `$bDEOP$b removes the given user (or yourself) from a channel admin.`,
-			authRequired: true,
-			enabled:      chanregEnabled,
-			minParams:    1,
+			helpShort: `$bDEOP$b removes the given user (or yourself) from a channel admin.`,
+			enabled:   chanregEnabled,
+			minParams: 1,
 		},
 		"register": {
 			handler: csRegisterHandler,
@@ -194,7 +193,6 @@ func csNotice(rb *ResponseBuffer, text string) {
 	rb.Add(nil, chanservMask, "NOTICE", rb.target.Nick(), text)
 }
 
-
 func csAmodeHandler(server *Server, client *Client, command string, params []string, rb *ResponseBuffer) {
 	channelName := params[0]
 
@@ -325,16 +323,13 @@ func csOpHandler(server *Server, client *Client, command string, params []string
 }
 
 func csDeopHandler(server *Server, client *Client, command string, params []string, rb *ResponseBuffer) {
-	channelInfo := server.channels.Get(params[0])
-	if channelInfo == nil {
+	channel := server.channels.Get(params[0])
+	if channel == nil {
 		csNotice(rb, client.t("Channel does not exist"))
 		return
 	}
-	channelName := channelInfo.Name()
-
-	clientAccount := client.Account()
-	if clientAccount == "" || clientAccount != channelInfo.Founder() {
-		csNotice(rb, client.t("Only the channel founder can do this"))
+	if !channel.hasClient(client) {
+		csNotice(rb, client.t("You're not on that channel"))
 		return
 	}
 
@@ -349,29 +344,35 @@ func csDeopHandler(server *Server, client *Client, command string, params []stri
 		target = client
 	}
 
-	// give them privs
-	givenMode := modes.ChannelOperator
-	if clientAccount == target.Account() {
-		givenMode = modes.ChannelFounder
+	present, cumodes := channel.ClientStatus(target)
+	if !present || len(cumodes) == 0 {
+		csNotice(rb, client.t("Target has no privileges to remove"))
+		return
 	}
-	applied, change := channelInfo.applyModeToMember(client,
-		modes.ModeChange{Mode: givenMode,
-			Op:  modes.Remove,
-			Arg: target.NickCasefolded(),
-		},
-		rb)
-	if applied {
-		announceCmodeChanges(channelInfo, modes.ModeChanges{change}, chanservMask, "*", "", rb)
+
+	tnick := target.Nick()
+	modeChanges := make(modes.ModeChanges, len(cumodes))
+	for i, mode := range cumodes {
+		modeChanges[i] = modes.ModeChange{
+			Mode: mode,
+			Op:   modes.Remove,
+			Arg:  tnick,
+		}
+	}
+
+	// use the user's own permissions for the check, then announce
+	// the changes as coming from chanserv
+	applied := channel.ApplyChannelModeChanges(client, false, modeChanges, rb)
+	details := client.Details()
+	announceCmodeChanges(channel, applied, details.nickMask, details.accountName, details.account, rb)
+
+	if len(applied) == 0 {
+		return
 	}
 
 	csNotice(rb, client.t("Successfully removed operator privileges"))
-	
-	tnick := target.Nick()
-	server.logger.Info("services", fmt.Sprintf("Client %s deop'd [%s] in channel %s", client.Nick(), tnick, channelName))
-	server.snomasks.Send(sno.LocalChannels, fmt.Sprintf(ircfmt.Unescape("Client $c[grey][$r%s$c[grey]] CS deOP'd $c[grey][$r%s$c[grey]] in channel $c[grey][$r%s$c[grey]]"), client.NickMaskString(), tnick, channelName))
 }
 
-
 func csRegisterHandler(server *Server, client *Client, command string, params []string, rb *ResponseBuffer) {
 	if server.Config().Channels.Registration.OperatorOnly && !client.HasRoleCapabs("chanreg") {
 		csNotice(rb, client.t("Channel registration is restricted to server operators"))