PLT-1598 Slash command works in RHS (#4367)

* PLT-1598 Slash command works in RHS

* fix UserProfile in the reply for Slash Command

* fix some problem about the system messages in RHS
* system message in RHS isn't displayed as comment for root message

* remove status indicator for system message in RHS

* system message in RHS is colored to grey

* system messages don't count as commented post

* fix bug about cleaning draft in RHS

* remove unnecessary function

* implement new model for executing command

35 files changed, 186 insertions, 79 deletions

diff --git a/api/command.go b/api/command.go
index 3ae379819..a6c3ea201 100644
--- a/api/command.go
+++ b/api/command.go
@@ -20,7 +20,7 @@ import (
 type CommandProvider interface {
 	GetTrigger() string
 	GetCommand(c *Context) *model.Command
-	DoCommand(c *Context, channelId string, message string) *model.CommandResponse
+	DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse
 }
 
 var commandProviders = make(map[string]CommandProvider)
@@ -88,30 +88,28 @@ func listCommands(c *Context, w http.ResponseWriter, r *http.Request) {
 }
 
 func executeCommand(c *Context, w http.ResponseWriter, r *http.Request) {
-	props := model.MapFromJson(r.Body)
-	command := strings.TrimSpace(props["command"])
-	channelId := strings.TrimSpace(props["channelId"])
+	commandArgs := model.CommandArgsFromJson(r.Body)
 
-	if len(command) <= 1 || strings.Index(command, "/") != 0 {
+	if len(commandArgs.Command) <= 1 || strings.Index(commandArgs.Command, "/") != 0 {
 		c.Err = model.NewLocAppError("executeCommand", "api.command.execute_command.start.app_error", nil, "")
 		return
 	}
 
-	if len(channelId) > 0 {
-		if !HasPermissionToChannelContext(c, channelId, model.PERMISSION_USE_SLASH_COMMANDS) {
+	if len(commandArgs.ChannelId) > 0 {
+		if !HasPermissionToChannelContext(c, commandArgs.ChannelId, model.PERMISSION_USE_SLASH_COMMANDS) {
 			return
 		}
 	}
 
-	parts := strings.Split(command, " ")
+	parts := strings.Split(commandArgs.Command, " ")
 	trigger := parts[0][1:]
 	trigger = strings.ToLower(trigger)
 	message := strings.Join(parts[1:], " ")
 	provider := GetCommandProvider(trigger)
 
 	if provider != nil {
-		response := provider.DoCommand(c, channelId, message)
-		handleResponse(c, w, response, channelId, provider.GetCommand(c), true)
+		response := provider.DoCommand(c, commandArgs, message)
+		handleResponse(c, w, response, commandArgs, provider.GetCommand(c), true)
 		return
 	} else {
 
@@ -121,7 +119,7 @@ func executeCommand(c *Context, w http.ResponseWriter, r *http.Request) {
 			return
 		}
 
-		chanChan := Srv.Store.Channel().Get(channelId)
+		chanChan := Srv.Store.Channel().Get(commandArgs.ChannelId)
 		teamChan := Srv.Store.Team().Get(c.TeamId)
 		userChan := Srv.Store.User().Get(c.Session.UserId)
 
@@ -166,7 +164,7 @@ func executeCommand(c *Context, w http.ResponseWriter, r *http.Request) {
 					p.Set("team_id", cmd.TeamId)
 					p.Set("team_domain", team.Name)
 
-					p.Set("channel_id", channelId)
+					p.Set("channel_id", commandArgs.ChannelId)
 					p.Set("channel_name", channel.Name)
 
 					p.Set("user_id", c.Session.UserId)
@@ -200,7 +198,7 @@ func executeCommand(c *Context, w http.ResponseWriter, r *http.Request) {
 							if response == nil {
 								c.Err = model.NewLocAppError("command", "api.command.execute_command.failed_empty.app_error", map[string]interface{}{"Trigger": trigger}, "")
 							} else {
-								handleResponse(c, w, response, channelId, cmd, false)
+								handleResponse(c, w, response, commandArgs, cmd, false)
 							}
 						} else {
 							defer resp.Body.Close()
@@ -219,10 +217,11 @@ func executeCommand(c *Context, w http.ResponseWriter, r *http.Request) {
 	c.Err = model.NewLocAppError("command", "api.command.execute_command.not_found.app_error", map[string]interface{}{"Trigger": trigger}, "")
 }
 
-func handleResponse(c *Context, w http.ResponseWriter, response *model.CommandResponse, channelId string, cmd *model.Command, builtIn bool) {
-
+func handleResponse(c *Context, w http.ResponseWriter, response *model.CommandResponse, commandArgs *model.CommandArgs, cmd *model.Command, builtIn bool) {
 	post := &model.Post{}
-	post.ChannelId = channelId
+	post.ChannelId = commandArgs.ChannelId
+	post.RootId = commandArgs.RootId
+	post.ParentId = commandArgs.ParentId
 
 	if !builtIn {
 		post.AddProp("from_webhook", "true")
@@ -258,6 +257,7 @@ func handleResponse(c *Context, w http.ResponseWriter, response *model.CommandRe
 		post.Message = response.Text
 		post.CreateAt = model.GetMillis()
 		post.UserId = c.Session.UserId
+		post.ParentId = ""
 		SendEphemeralPost(
 			c.TeamId,
 			c.Session.UserId,
diff --git a/api/command_away.go b/api/command_away.go
index 55ce7846e..6d6540320 100644
--- a/api/command_away.go
+++ b/api/command_away.go
@@ -31,7 +31,7 @@ func (me *AwayProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *AwayProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *AwayProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	rmsg := c.T("api.command_away.success")
 	if len(message) > 0 {
 		rmsg = message + " " + rmsg
diff --git a/api/command_echo.go b/api/command_echo.go
index 997ee0751..4f6f6e33a 100644
--- a/api/command_echo.go
+++ b/api/command_echo.go
@@ -39,7 +39,7 @@ func (me *EchoProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *EchoProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *EchoProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	maxThreads := 100
 
 	delay := 0
@@ -75,7 +75,9 @@ func (me *EchoProvider) DoCommand(c *Context, channelId string, message string)
 	go func() {
 		defer func() { <-echoSem }()
 		post := &model.Post{}
-		post.ChannelId = channelId
+		post.ChannelId = args.ChannelId
+		post.RootId = args.RootId
+		post.ParentId = args.ParentId
 		post.Message = message
 		post.UserId = c.Session.UserId
 
diff --git a/api/command_echo_test.go b/api/command_echo_test.go
index 26fba007c..71a378242 100644
--- a/api/command_echo_test.go
+++ b/api/command_echo_test.go
@@ -17,7 +17,7 @@ func TestEchoCommand(t *testing.T) {
 
 	echoTestString := "/echo test"
 
-	r1 := Client.Must(Client.Command(channel1.Id, echoTestString, false)).Data.(*model.CommandResponse)
+	r1 := Client.Must(Client.Command(channel1.Id, echoTestString)).Data.(*model.CommandResponse)
 	if r1 == nil {
 		t.Fatal("Echo command failed to execute")
 	}
diff --git a/api/command_expand_collapse.go b/api/command_expand_collapse.go
index ee018cf8f..afd17a6fc 100644
--- a/api/command_expand_collapse.go
+++ b/api/command_expand_collapse.go
@@ -49,11 +49,11 @@ func (me *CollapseProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *ExpandProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *ExpandProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	return setCollapsePreference(c, "false")
 }
 
-func (me *CollapseProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *CollapseProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	return setCollapsePreference(c, "true")
 }
 
diff --git a/api/command_expand_collapse_test.go b/api/command_expand_collapse_test.go
index 2303b2fed..bad5ef6c4 100644
--- a/api/command_expand_collapse_test.go
+++ b/api/command_expand_collapse_test.go
@@ -15,7 +15,7 @@ func TestExpandCommand(t *testing.T) {
 	Client := th.BasicClient
 	channel := th.BasicChannel
 
-	r1 := Client.Must(Client.Command(channel.Id, "/expand", false)).Data.(*model.CommandResponse)
+	r1 := Client.Must(Client.Command(channel.Id, "/expand")).Data.(*model.CommandResponse)
 	if r1 == nil {
 		t.Fatal("Command failed to execute")
 	}
@@ -33,7 +33,7 @@ func TestCollapseCommand(t *testing.T) {
 	Client := th.BasicClient
 	channel := th.BasicChannel
 
-	r1 := Client.Must(Client.Command(channel.Id, "/collapse", false)).Data.(*model.CommandResponse)
+	r1 := Client.Must(Client.Command(channel.Id, "/collapse")).Data.(*model.CommandResponse)
 	if r1 == nil {
 		t.Fatal("Command failed to execute")
 	}
diff --git a/api/command_invite_people.go b/api/command_invite_people.go
index 93f8f85eb..ca2a2633a 100644
--- a/api/command_invite_people.go
+++ b/api/command_invite_people.go
@@ -35,7 +35,7 @@ func (me *InvitePeopleProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *InvitePeopleProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *InvitePeopleProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	if !utils.Cfg.EmailSettings.SendEmailNotifications {
 		return &model.CommandResponse{ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL, Text: c.T("api.command.invite_people.email_off")}
 	}
diff --git a/api/command_invite_people_test.go b/api/command_invite_people_test.go
index 3efc87e60..d4f579c4d 100644
--- a/api/command_invite_people_test.go
+++ b/api/command_invite_people_test.go
@@ -14,17 +14,17 @@ func TestInvitePeopleCommand(t *testing.T) {
 	Client := th.BasicClient
 	channel := th.BasicChannel
 
-	r1 := Client.Must(Client.Command(channel.Id, "/invite_people test@example.com", false)).Data.(*model.CommandResponse)
+	r1 := Client.Must(Client.Command(channel.Id, "/invite_people test@example.com")).Data.(*model.CommandResponse)
 	if r1 == nil {
 		t.Fatal("Command failed to execute")
 	}
 
-	r2 := Client.Must(Client.Command(channel.Id, "/invite_people test1@example.com test2@example.com", false)).Data.(*model.CommandResponse)
+	r2 := Client.Must(Client.Command(channel.Id, "/invite_people test1@example.com test2@example.com")).Data.(*model.CommandResponse)
 	if r2 == nil {
 		t.Fatal("Command failed to execute")
 	}
 
-	r3 := Client.Must(Client.Command(channel.Id, "/invite_people", false)).Data.(*model.CommandResponse)
+	r3 := Client.Must(Client.Command(channel.Id, "/invite_people")).Data.(*model.CommandResponse)
 	if r3 == nil {
 		t.Fatal("Command failed to execute")
 	}
diff --git a/api/command_join.go b/api/command_join.go
index 0499d503d..3c997dffd 100644
--- a/api/command_join.go
+++ b/api/command_join.go
@@ -32,7 +32,7 @@ func (me *JoinProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *JoinProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *JoinProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	if result := <-Srv.Store.Channel().GetByName(c.TeamId, message); result.Err != nil {
 		return &model.CommandResponse{Text: c.T("api.command_join.list.app_error"), ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL}
 	} else {
diff --git a/api/command_join_test.go b/api/command_join_test.go
index a1dbace41..cce837ceb 100644
--- a/api/command_join_test.go
+++ b/api/command_join_test.go
@@ -29,12 +29,12 @@ func TestJoinCommands(t *testing.T) {
 
 	channel3 := Client.Must(Client.CreateDirectChannel(user2.Id)).Data.(*model.Channel)
 
-	rs5 := Client.Must(Client.Command(channel0.Id, "/join "+channel2.Name, false)).Data.(*model.CommandResponse)
+	rs5 := Client.Must(Client.Command(channel0.Id, "/join "+channel2.Name)).Data.(*model.CommandResponse)
 	if !strings.HasSuffix(rs5.GotoLocation, "/"+team.Name+"/channels/"+channel2.Name) {
 		t.Fatal("failed to join channel")
 	}
 
-	rs6 := Client.Must(Client.Command(channel0.Id, "/join "+channel3.Name, false)).Data.(*model.CommandResponse)
+	rs6 := Client.Must(Client.Command(channel0.Id, "/join "+channel3.Name)).Data.(*model.CommandResponse)
 	if strings.HasSuffix(rs6.GotoLocation, "/"+team.Name+"/channels/"+channel3.Name) {
 		t.Fatal("should not have joined direct message channel")
 	}
diff --git a/api/command_loadtest.go b/api/command_loadtest.go
index 8f5163a66..ed3fc37ba 100644
--- a/api/command_loadtest.go
+++ b/api/command_loadtest.go
@@ -84,7 +84,8 @@ func (me *LoadTestProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *LoadTestProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *LoadTestProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
+	channelId := args.ChannelId
 
 	//This command is only available when EnableTesting is true
 	if !utils.Cfg.ServiceSettings.EnableTesting {
diff --git a/api/command_loadtest_test.go b/api/command_loadtest_test.go
index 9371e5960..091e05831 100644
--- a/api/command_loadtest_test.go
+++ b/api/command_loadtest_test.go
@@ -25,7 +25,7 @@ func TestLoadTestHelpCommands(t *testing.T) {
 
 	utils.Cfg.ServiceSettings.EnableTesting = true
 
-	rs := Client.Must(Client.Command(channel.Id, "/loadtest help", false)).Data.(*model.CommandResponse)
+	rs := Client.Must(Client.Command(channel.Id, "/loadtest help")).Data.(*model.CommandResponse)
 	if !strings.Contains(rs.Text, "Mattermost load testing commands to help") {
 		t.Fatal(rs.Text)
 	}
@@ -46,7 +46,7 @@ func TestLoadTestSetupCommands(t *testing.T) {
 
 	utils.Cfg.ServiceSettings.EnableTesting = true
 
-	rs := Client.Must(Client.Command(channel.Id, "/loadtest setup fuzz 1 1 1", false)).Data.(*model.CommandResponse)
+	rs := Client.Must(Client.Command(channel.Id, "/loadtest setup fuzz 1 1 1")).Data.(*model.CommandResponse)
 	if rs.Text != "Created enviroment" {
 		t.Fatal(rs.Text)
 	}
@@ -67,7 +67,7 @@ func TestLoadTestUsersCommands(t *testing.T) {
 
 	utils.Cfg.ServiceSettings.EnableTesting = true
 
-	rs := Client.Must(Client.Command(channel.Id, "/loadtest users fuzz 1 2", false)).Data.(*model.CommandResponse)
+	rs := Client.Must(Client.Command(channel.Id, "/loadtest users fuzz 1 2")).Data.(*model.CommandResponse)
 	if rs.Text != "Added users" {
 		t.Fatal(rs.Text)
 	}
@@ -88,7 +88,7 @@ func TestLoadTestChannelsCommands(t *testing.T) {
 
 	utils.Cfg.ServiceSettings.EnableTesting = true
 
-	rs := Client.Must(Client.Command(channel.Id, "/loadtest channels fuzz 1 2", false)).Data.(*model.CommandResponse)
+	rs := Client.Must(Client.Command(channel.Id, "/loadtest channels fuzz 1 2")).Data.(*model.CommandResponse)
 	if rs.Text != "Added channels" {
 		t.Fatal(rs.Text)
 	}
@@ -109,7 +109,7 @@ func TestLoadTestPostsCommands(t *testing.T) {
 
 	utils.Cfg.ServiceSettings.EnableTesting = true
 
-	rs := Client.Must(Client.Command(channel.Id, "/loadtest posts fuzz 2 3 2", false)).Data.(*model.CommandResponse)
+	rs := Client.Must(Client.Command(channel.Id, "/loadtest posts fuzz 2 3 2")).Data.(*model.CommandResponse)
 	if rs.Text != "Added posts" {
 		t.Fatal(rs.Text)
 	}
diff --git a/api/command_logout.go b/api/command_logout.go
index 9fff4e2d5..474f0b58e 100644
--- a/api/command_logout.go
+++ b/api/command_logout.go
@@ -32,7 +32,7 @@ func (me *LogoutProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *LogoutProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *LogoutProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	FAIL := &model.CommandResponse{ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL, Text: c.T("api.command_logout.fail_message")}
 	SUCCESS := &model.CommandResponse{GotoLocation: "/", ResponseType: model.COMMAND_RESPONSE_TYPE_EPHEMERAL, Text: c.T("api.command_logout.success_message")}
 
diff --git a/api/command_logout_test.go b/api/command_logout_test.go
index 6d74549af..d61b30633 100644
--- a/api/command_logout_test.go
+++ b/api/command_logout_test.go
@@ -10,5 +10,5 @@ import (
 func TestLogoutTestCommand(t *testing.T) {
 	th := Setup().InitBasic()
 
-	th.BasicClient.Must(th.BasicClient.Command(th.BasicChannel.Id, "/logout", false))
+	th.BasicClient.Must(th.BasicClient.Command(th.BasicChannel.Id, "/logout"))
 }
diff --git a/api/command_me.go b/api/command_me.go
index c6147278b..a3cda472a 100644
--- a/api/command_me.go
+++ b/api/command_me.go
@@ -32,6 +32,6 @@ func (me *MeProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *MeProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *MeProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	return &model.CommandResponse{ResponseType: model.COMMAND_RESPONSE_TYPE_IN_CHANNEL, Text: "*" + message + "*"}
 }
diff --git a/api/command_me_test.go b/api/command_me_test.go
index f466f5764..0250cfb0f 100644
--- a/api/command_me_test.go
+++ b/api/command_me_test.go
@@ -17,7 +17,7 @@ func TestMeCommand(t *testing.T) {
 
 	testString := "/me hello"
 
-	r1 := Client.Must(Client.Command(channel.Id, testString, false)).Data.(*model.CommandResponse)
+	r1 := Client.Must(Client.Command(channel.Id, testString)).Data.(*model.CommandResponse)
 	if r1 == nil {
 		t.Fatal("Command failed to execute")
 	}
diff --git a/api/command_msg.go b/api/command_msg.go
index 2e0e25397..8a9949544 100644
--- a/api/command_msg.go
+++ b/api/command_msg.go
@@ -34,7 +34,7 @@ func (me *msgProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *msgProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *msgProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 
 	splitMessage := strings.SplitN(message, " ", 2)
 
diff --git a/api/command_msg_test.go b/api/command_msg_test.go
index f11fce091..ad1c8d5ce 100644
--- a/api/command_msg_test.go
+++ b/api/command_msg_test.go
@@ -21,12 +21,12 @@ func TestMsgCommands(t *testing.T) {
 	Client.Must(Client.CreateDirectChannel(user2.Id))
 	Client.Must(Client.CreateDirectChannel(user3.Id))
 
-	rs1 := Client.Must(Client.Command("", "/msg "+user2.Username, false)).Data.(*model.CommandResponse)
+	rs1 := Client.Must(Client.Command("", "/msg "+user2.Username)).Data.(*model.CommandResponse)
 	if !strings.HasSuffix(rs1.GotoLocation, "/"+team.Name+"/channels/"+user1.Id+"__"+user2.Id) && !strings.HasSuffix(rs1.GotoLocation, "/"+team.Name+"/channels/"+user2.Id+"__"+user1.Id) {
 		t.Fatal("failed to create direct channel")
 	}
 
-	rs2 := Client.Must(Client.Command("", "/msg "+user3.Username+" foobar", false)).Data.(*model.CommandResponse)
+	rs2 := Client.Must(Client.Command("", "/msg "+user3.Username+" foobar")).Data.(*model.CommandResponse)
 	if !strings.HasSuffix(rs2.GotoLocation, "/"+team.Name+"/channels/"+user1.Id+"__"+user3.Id) && !strings.HasSuffix(rs2.GotoLocation, "/"+team.Name+"/channels/"+user3.Id+"__"+user1.Id) {
 		t.Fatal("failed to create second direct channel")
 	}
@@ -34,7 +34,7 @@ func TestMsgCommands(t *testing.T) {
 		t.Fatalf("post did not get sent to direct message")
 	}
 
-	rs3 := Client.Must(Client.Command("", "/msg "+user2.Username, false)).Data.(*model.CommandResponse)
+	rs3 := Client.Must(Client.Command("", "/msg "+user2.Username)).Data.(*model.CommandResponse)
 	if !strings.HasSuffix(rs3.GotoLocation, "/"+team.Name+"/channels/"+user1.Id+"__"+user2.Id) && !strings.HasSuffix(rs3.GotoLocation, "/"+team.Name+"/channels/"+user2.Id+"__"+user1.Id) {
 		t.Fatal("failed to go back to existing direct channel")
 	}
diff --git a/api/command_offline.go b/api/command_offline.go
index a9e2123d3..1349ac18f 100644
--- a/api/command_offline.go
+++ b/api/command_offline.go
@@ -31,7 +31,7 @@ func (me *OfflineProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *OfflineProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *OfflineProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	rmsg := c.T("api.command_offline.success")
 	if len(message) > 0 {
 		rmsg = message + " " + rmsg
diff --git a/api/command_online.go b/api/command_online.go
index 71ada5b7a..887aa2c47 100644
--- a/api/command_online.go
+++ b/api/command_online.go
@@ -31,7 +31,7 @@ func (me *OnlineProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *OnlineProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *OnlineProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	rmsg := c.T("api.command_online.success")
 	if len(message) > 0 {
 		rmsg = message + " " + rmsg
diff --git a/api/command_shortcuts.go b/api/command_shortcuts.go
index dfbb7071d..f75b419b1 100644
--- a/api/command_shortcuts.go
+++ b/api/command_shortcuts.go
@@ -35,7 +35,7 @@ func (me *ShortcutsProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *ShortcutsProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *ShortcutsProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	shortcutIds := [4]string{
 		"api.command_shortcuts.nav",
 		"api.command_shortcuts.files",
diff --git a/api/command_shortcuts_test.go b/api/command_shortcuts_test.go
index 01c56b465..049175ec9 100644
--- a/api/command_shortcuts_test.go
+++ b/api/command_shortcuts_test.go
@@ -14,12 +14,12 @@ func TestShortcutsCommand(t *testing.T) {
 	Client := th.BasicClient
 	channel := th.BasicChannel
 
-	rs := Client.Must(Client.Command(channel.Id, "/shortcuts ", false)).Data.(*model.CommandResponse)
+	rs := Client.Must(Client.Command(channel.Id, "/shortcuts ")).Data.(*model.CommandResponse)
 	if !strings.Contains(rs.Text, "CTRL") {
 		t.Fatal("failed to display shortcuts")
 	}
 
-	rs = Client.Must(Client.Command(channel.Id, "/shortcuts mac", false)).Data.(*model.CommandResponse)
+	rs = Client.Must(Client.Command(channel.Id, "/shortcuts mac")).Data.(*model.CommandResponse)
 	if !strings.Contains(rs.Text, "CMD") {
 		t.Fatal("failed to display Mac shortcuts")
 	}
diff --git a/api/command_shrug.go b/api/command_shrug.go
index 8fb5bc200..899fcab33 100644
--- a/api/command_shrug.go
+++ b/api/command_shrug.go
@@ -32,7 +32,7 @@ func (me *ShrugProvider) GetCommand(c *Context) *model.Command {
 	}
 }
 
-func (me *ShrugProvider) DoCommand(c *Context, channelId string, message string) *model.CommandResponse {
+func (me *ShrugProvider) DoCommand(c *Context, args *model.CommandArgs, message string) *model.CommandResponse {
 	rmsg := `¯\\\_(ツ)\_/¯`
 	if len(message) > 0 {
 		rmsg = message + " " + rmsg
diff --git a/api/command_shrug_test.go b/api/command_shrug_test.go
index 99c10d191..e64f4c4b1 100644
--- a/api/command_shrug_test.go
+++ b/api/command_shrug_test.go
@@ -17,7 +17,7 @@ func TestShrugCommand(t *testing.T) {
 
 	testString := "/shrug"
 
-	r1 := Client.Must(Client.Command(channel.Id, testString, false)).Data.(*model.CommandResponse)
+	r1 := Client.Must(Client.Command(channel.Id, testString)).Data.(*model.CommandResponse)
 	if r1 == nil {
 		t.Fatal("Command failed to execute")
 	}
diff --git a/api/command_statuses_test.go b/api/command_statuses_test.go
index 73c6354f4..47628de3f 100644
--- a/api/command_statuses_test.go
+++ b/api/command_statuses_test.go
@@ -22,7 +22,7 @@ func commandAndTest(t *testing.T, th *TestHelper, status string) {
 	channel := th.BasicChannel
 	user := th.BasicUser
 
-	r1 := Client.Must(Client.Command(channel.Id, "/"+status, false)).Data.(*model.CommandResponse)
+	r1 := Client.Must(Client.Command(channel.Id, "/"+status)).Data.(*model.CommandResponse)
 	if r1 == nil {
 		t.Fatal("Command failed to execute")
 	}
diff --git a/api/command_test.go b/api/command_test.go
index 45268a9a5..726a9cb9b 100644
--- a/api/command_test.go
+++ b/api/command_test.go
@@ -246,7 +246,7 @@ func TestTestCommand(t *testing.T) {
 
 	cmd1 = Client.Must(Client.CreateCommand(cmd1)).Data.(*model.Command)
 
-	r1 := Client.Must(Client.Command(channel1.Id, "/test", false)).Data.(*model.CommandResponse)
+	r1 := Client.Must(Client.Command(channel1.Id, "/test")).Data.(*model.CommandResponse)
 	if r1 == nil {
 		t.Fatal("Test command failed to execute")
 	}
@@ -266,7 +266,7 @@ func TestTestCommand(t *testing.T) {
 
 	cmd2 = Client.Must(Client.CreateCommand(cmd2)).Data.(*model.Command)
 
-	r2 := Client.Must(Client.Command(channel1.Id, "/test2", false)).Data.(*model.CommandResponse)
+	r2 := Client.Must(Client.Command(channel1.Id, "/test2")).Data.(*model.CommandResponse)
 	if r2 == nil {
 		t.Fatal("Test2 command failed to execute")
 	}
diff --git a/model/client.go b/model/client.go
index 510ba461f..951b3388a 100644
--- a/model/client.go
+++ b/model/client.go
@@ -826,12 +826,9 @@ func (c *Client) EmailToLDAP(m map[string]string) (*Result, *AppError) {
 	}
 }
 
-func (c *Client) Command(channelId string, command string, suggest bool) (*Result, *AppError) {
-	m := make(map[string]string)
-	m["command"] = command
-	m["channelId"] = channelId
-	m["suggest"] = strconv.FormatBool(suggest)
-	if r, err := c.DoApiPost(c.GetTeamRoute()+"/commands/execute", MapToJson(m)); err != nil {
+func (c *Client) Command(channelId string, command string) (*Result, *AppError) {
+	args := &CommandArgs{ChannelId: channelId, Command: command}
+	if r, err := c.DoApiPost(c.GetTeamRoute()+"/commands/execute", args.ToJson()); err != nil {
 		return nil, err
 	} else {
 		defer closeBody(r)
diff --git a/model/command_args.go b/model/command_args.go
new file mode 100644
index 000000000..4da5dc760
--- /dev/null
+++ b/model/command_args.go
@@ -0,0 +1,36 @@
+// Copyright (c) 2016 Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package model
+
+import (
+	"encoding/json"
+	"io"
+)
+
+type CommandArgs struct {
+	ChannelId string `json:"channel_id"`
+	RootId    string `json:"root_id"`
+	ParentId  string `json:"parent_id"`
+	Command   string `json:"command"`
+}
+
+func (o *CommandArgs) ToJson() string {
+	b, err := json.Marshal(o)
+	if err != nil {
+		return ""
+	} else {
+		return string(b)
+	}
+}
+
+func CommandArgsFromJson(data io.Reader) *CommandArgs {
+	decoder := json.NewDecoder(data)
+	var o CommandArgs
+	err := decoder.Decode(&o)
+	if err == nil {
+		return &o
+	} else {
+		return nil
+	}
+}
diff --git a/webapp/actions/channel_actions.jsx b/webapp/actions/channel_actions.jsx
index b108633d7..12e58177d 100644
--- a/webapp/actions/channel_actions.jsx
+++ b/webapp/actions/channel_actions.jsx
@@ -32,7 +32,7 @@ export function goToChannel(channel) {
     }
 }
 
-export function executeCommand(channelId, message, suggest, success, error) {
+export function executeCommand(message, args, success, error) {
     let msg = message;
 
     msg = msg.substring(0, msg.indexOf(' ')).toLowerCase() + msg.substring(msg.indexOf(' '), msg.length);
@@ -48,8 +48,7 @@ export function executeCommand(channelId, message, suggest, success, error) {
             msg = '/shortcuts';
         }
     }
-
-    Client.executeCommand(channelId, msg, suggest, success, error);
+    Client.executeCommand(msg, args, success, error);
 }
 
 export function setChannelAsRead(channelIdParam) {
diff --git a/webapp/client/client.jsx b/webapp/client/client.jsx
index d8218490e..398ce4f83 100644
--- a/webapp/client/client.jsx
+++ b/webapp/client/client.jsx
@@ -1494,13 +1494,13 @@ export default class Client {
             end(this.handleResponse.bind(this, 'listCommands', success, error));
     }
 
-    executeCommand(channelId, command, suggest, success, error) {
+    executeCommand(command, commandArgs, success, error) {
         request.
             post(`${this.getCommandsRoute()}/execute`).
             set(this.defaultHeaders).
             type('application/json').
             accept('application/json').
-            send({channelId, command, suggest: String(suggest)}).
+            send({command, ...commandArgs}).
             end(this.handleResponse.bind(this, 'executeCommand', success, error));
 
         this.track('api', 'api_integrations_used');
diff --git a/webapp/components/create_comment.jsx b/webapp/components/create_comment.jsx
index a235691b4..3bd8d5d1c 100644
--- a/webapp/components/create_comment.jsx
+++ b/webapp/components/create_comment.jsx
@@ -4,6 +4,7 @@
 import $ from 'jquery';
 import ReactDOM from 'react-dom';
 import AppDispatcher from '../dispatcher/app_dispatcher.jsx';
+import * as ChannelActions from 'actions/channel_actions.jsx';
 import EmojiStore from 'stores/emoji_store.jsx';
 import UserStore from 'stores/user_store.jsx';
 import PostDeletedModal from './post_deleted_modal.jsx';
@@ -22,6 +23,7 @@ import * as PostActions from 'actions/post_actions.jsx';
 import Constants from 'utils/constants.jsx';
 
 import {FormattedMessage} from 'react-intl';
+import {browserHistory} from 'react-router/es6';
 
 const ActionTypes = Constants.ActionTypes;
 const KeyCodes = Constants.KeyCodes;
@@ -121,7 +123,6 @@ export default class CreateComment extends React.Component {
         }
 
         MessageHistoryStore.storeMessageInHistory(message);
-
         if (message.trim().length === 0 && this.state.fileInfos.length === 0) {
             return;
         }
@@ -129,6 +130,8 @@ export default class CreateComment extends React.Component {
         const isReaction = REACTION_PATTERN.exec(message);
         if (isReaction && EmojiStore.has(isReaction[2])) {
             this.handleSubmitReaction(isReaction);
+        } else if (message.indexOf('/') === 0) {
+            this.handleSubmitCommand(message);
         } else {
             this.handleSubmitPost(message);
         }
@@ -146,6 +149,36 @@ export default class CreateComment extends React.Component {
         this.focusTextbox(forceFocus);
     }
 
+    handleSubmitCommand(message) {
+        PostStore.storeCommentDraft(this.props.rootId, null);
+        this.setState({message: '', postError: null, fileInfos: []});
+
+        const args = {};
+        args.channel_id = this.props.channelId;
+        args.root_id = this.props.rootId;
+        args.parent_id = this.props.rootId;
+        ChannelActions.executeCommand(
+            message,
+            args,
+            (data) => {
+                this.setState({submitting: false});
+                if (data.goto_location && data.goto_location.length > 0) {
+                    browserHistory.push(data.goto_location);
+                }
+            },
+            (err) => {
+                if (err.sendMessage) {
+                    this.handleSubmitPost(message);
+                } else {
+                    const state = {};
+                    state.serverError = err.message;
+                    state.submitting = false;
+                    this.setState(state);
+                }
+            }
+        );
+    }
+
     handleSubmitPost(message) {
         const userId = UserStore.getCurrentId();
         const time = Utils.getTimestamp();
@@ -444,7 +477,6 @@ export default class CreateComment extends React.Component {
                                 onBlur={this.handleBlur}
                                 createMessage={Utils.localizeMessage('create_comment.addComment', 'Add a comment...')}
                                 initialText=''
-                                supportsCommands={false}
                                 channelId={this.props.channelId}
                                 id='reply_textbox'
                                 ref='textbox'
diff --git a/webapp/components/create_post.jsx b/webapp/components/create_post.jsx
index 6bd5f0293..24ebd60b5 100644
--- a/webapp/components/create_post.jsx
+++ b/webapp/components/create_post.jsx
@@ -112,10 +112,11 @@ export default class CreatePost extends React.Component {
             PostStore.storeDraft(this.state.channelId, null);
             this.setState({message: '', postError: null, fileInfos: []});
 
+            const args = {};
+            args.channel_id = this.state.channelId;
             ChannelActions.executeCommand(
-                this.state.channelId,
                 post.message,
-                false,
+                args,
                 (data) => {
                     this.setState({submitting: false});
 
@@ -357,10 +358,11 @@ export default class CreatePost extends React.Component {
     showShortcuts(e) {
         if ((e.ctrlKey || e.metaKey) && e.keyCode === Constants.KeyCodes.FORWARD_SLASH) {
             e.preventDefault();
+            const args = {};
+            args.channel_id = this.state.channelId;
             ChannelActions.executeCommand(
-                this.state.channelId,
-                '/shortcuts ',
-                false,
+                '/shortcuts',
+                args,
                 null,
                 (err) => {
                     this.setState({
diff --git a/webapp/components/post_view/components/post_list.jsx b/webapp/components/post_view/components/post_list.jsx
index 157e0dde2..b3b83dfd6 100644
--- a/webapp/components/post_view/components/post_list.jsx
+++ b/webapp/components/post_view/components/post_list.jsx
@@ -293,7 +293,7 @@ export default class PostList extends React.Component {
 
             if (commentRootId) {
                 for (const postId in posts) {
-                    if (posts[postId].root_id === commentRootId) {
+                    if (posts[postId].root_id === commentRootId && !PostUtils.isSystemMessage(posts[postId])) {
                         commentCount += 1;
                         if (posts[postId].user_id === userId) {
                             shouldHighlightThreads = true;
diff --git a/webapp/components/rhs_comment.jsx b/webapp/components/rhs_comment.jsx
index bb04480ed..8b5d56c01 100644
--- a/webapp/components/rhs_comment.jsx
+++ b/webapp/components/rhs_comment.jsx
@@ -227,6 +227,8 @@ export default class RhsComment extends React.Component {
     render() {
         const post = this.props.post;
         const flagIcon = Constants.FLAG_ICON_SVG;
+        const mattermostLogo = Constants.MATTERMOST_ICON_SVG;
+        const isSystemMessage = PostUtils.isSystemMessage(post);
 
         var currentUserCss = '';
         if (this.props.currentUser === post.user_id) {
@@ -236,10 +238,31 @@ export default class RhsComment extends React.Component {
         var timestamp = this.props.currentUser.update_at;
 
         let botIndicator;
-
+        let userProfile = (
+            <UserProfile user={this.props.user}/>
+        );
         if (post.props && post.props.from_webhook) {
+            if (post.props.override_username && global.window.mm_config.EnablePostUsernameOverride === 'true') {
+                userProfile = (
+                    <UserProfile
+                        user={this.props.user}
+                        overwriteName={post.props.override_username}
+                        disablePopover={true}
+                    />
+                );
+            }
             botIndicator = <li className='bot-indicator'>{Constants.BOT_NAME}</li>;
+        } else if (isSystemMessage) {
+            userProfile = (
+                <UserProfile
+                    user={{}}
+                    overwriteName={Constants.SYSTEM_MESSAGE_PROFILE_NAME}
+                    overwriteImage={Constants.SYSTEM_MESSAGE_PROFILE_IMAGE}
+                    disablePopover={true}
+                />
+            );
         }
+
         let loading;
         let postClass = '';
         let message = <PostMessageContainer post={post}/>;
@@ -264,6 +287,11 @@ export default class RhsComment extends React.Component {
             );
         }
 
+        let systemMessageClass = '';
+        if (isSystemMessage) {
+            systemMessageClass = 'post--system';
+        }
+
         let status = this.props.status;
         if (post.props && post.props.from_webhook === 'true') {
             status = null;
@@ -279,6 +307,15 @@ export default class RhsComment extends React.Component {
             />
         );
 
+        if (isSystemMessage) {
+            profilePic = (
+                <span
+                    className='icon'
+                    dangerouslySetInnerHTML={{__html: mattermostLogo}}
+                />
+            );
+        }
+
         let compactClass = '';
         if (this.props.compactDisplay) {
             compactClass = 'post--compact';
@@ -387,13 +424,13 @@ export default class RhsComment extends React.Component {
         };
 
         return (
-            <div className={'post post--thread ' + currentUserCss + ' ' + compactClass}>
+            <div className={'post post--thread ' + currentUserCss + ' ' + compactClass + ' ' + systemMessageClass}>
                 <div className='post__content'>
                     {profilePicContainer}
                     <div>
                         <ul className='post__header'>
                             <li className='col col__name'>
-                                <strong><UserProfile user={this.props.user}/></strong>
+                                <strong>{userProfile}</strong>
                             </li>
                             {botIndicator}
                             <li className='col'>
diff --git a/webapp/tests/client_command.test.jsx b/webapp/tests/client_command.test.jsx
index 7d39537f8..e6795e5d7 100644
--- a/webapp/tests/client_command.test.jsx
+++ b/webapp/tests/client_command.test.jsx
@@ -38,10 +38,11 @@ describe('Client.Commands', function() {
 
     it('executeCommand', function(done) {
         TestHelper.initBasic(() => {
+            const args = {};
+            args.channel_id = TestHelper.basicChannel().id;
             TestHelper.basicClient().executeCommand(
-                TestHelper.basicChannel().id,
                 '/shrug',
-                null,
+                args,
                 function(data) {
                     assert.equal(data.response_type, 'in_channel');
                     done();