Allow admins to send service notifications (#38)

* Allow admins to send service notifications

Closes #33

* Fix test

bot/controller.go

@@ -57,6 +57,8 @@ const (
 	CMD_DELETE_ALL  = "deleteAll"
 	CMD_SUGGEST     = "suggestions"
 	CMD_CURRENCY    = "currency"
+
+	CMD_ADM_NOTIFY = "admin_notify"
 )
 
 func (bc *BotController) commandMappings() []*CMD {
@@ -70,6 +72,8 @@ func (bc *BotController) commandMappings() []*CMD {
 		{Command: CMD_CURRENCY, Handler: bc.commandCurrency, Help: "Set the currency to use globally for subsequent transactions"},
 		{Command: CMD_ARCHIVE_ALL, Handler: bc.commandArchiveTransactions, Help: "Archive recorded transactions"},
 		{Command: CMD_DELETE_ALL, Handler: bc.commandDeleteTransactions, Help: "Permanently delete recorded transactions"},
+
+		{Command: CMD_ADM_NOTIFY, Handler: bc.commandAdminNofify, Help: "Send notification to user(s): /" + CMD_ADM_NOTIFY + " [chatId] \"<message>\""},
 	}
 }
 
@@ -86,10 +90,15 @@ func (bc *BotController) commandStart(m *tb.Message) {
 func (bc *BotController) commandHelp(m *tb.Message) {
 	log.Printf("Sending help to %s (ChatID: %d)", m.Chat.Username, m.Chat.ID)
 	helpMsg := ""
+	adminCommands := []*CMD{}
 	for i, cmd := range bc.commandMappings() {
 		if cmd.Help == "" {
 			continue
 		}
+		if strings.HasPrefix(cmd.Command, "admin") {
+			adminCommands = append(adminCommands, cmd)
+			continue
+		}
 		if i != 0 {
 			helpMsg += "\n"
 		}
@@ -99,6 +108,12 @@ func (bc *BotController) commandHelp(m *tb.Message) {
 		}
 		helpMsg += fmt.Sprintf("/%s%s - %s", cmd.Command, optional, cmd.Help)
 	}
+	if len(adminCommands) > 0 && bc.Repo.UserIsAdmin(m) {
+		helpMsg += "\n\n** ADMIN COMMANDS **"
+		for _, cmd := range adminCommands {
+			helpMsg += fmt.Sprintf("\n/%s - %s", cmd.Command, cmd.Help)
+		}
+	}
 	bc.Bot.Send(m.Sender, helpMsg, clearKeyboard())
 }
 
@@ -200,6 +215,58 @@ func (bc *BotController) commandCurrency(m *tb.Message) {
 	bc.Bot.Send(m.Sender, fmt.Sprintf("For all future transactions the currency '%s' will be used.", currency))
 }
 
+type ReceiverImpl struct {
+	chatId string
+}
+
+func (r ReceiverImpl) Recipient() string {
+	return r.chatId
+}
+
+func (bc *BotController) commandAdminNofify(m *tb.Message) {
+	isAdmin := bc.Repo.UserIsAdmin(m)
+	if !isAdmin {
+		log.Printf("Received admin command from non-admin user (%s, %d). Ignoring (treating as normal text input).", m.Chat.Username, m.Chat.ID)
+		bc.handleTextState(m)
+		return
+	}
+	text := strings.Split(m.Text, "\"")
+	var notificationMessage string
+	if len(text) >= 2 {
+		notificationMessage = text[1]
+	}
+	if len(text) == 0 || len(notificationMessage) == 0 {
+		bc.Bot.Send(m.Sender, "Something went wrong splitting your command parameters. Did you specify a text in double quotes (\")?")
+		return
+	}
+	// text[0] = /command [chatId]
+	command := strings.Split(strings.TrimRight(text[0], " "), " ")
+
+	if len(command) == 0 || len(command) >= 3 {
+		// invalid argument count
+		bc.Bot.Send(m.Sender, "Please check the command syntax")
+		return
+	}
+
+	var target string
+	if len(command) == 2 {
+		target = command[1]
+	}
+
+	receivers := bc.Repo.IndividualsWithNotifications(m.Chat.ID, target)
+	if len(receivers) == 0 {
+		bc.Bot.Send(m.Sender, "No receivers found to send notification to (you being excluded).")
+		return
+	}
+
+	for _, recipient := range receivers {
+		bc.Bot.Send(ReceiverImpl{chatId: recipient}, "*** Service notification ***\n\n"+notificationMessage)
+		log.Printf("Sent notification to %s", recipient)
+		// TODO: Add message like 'If you don't want to receive further service notifications, you can turn them off in the /settings with '/settings notif off'.'
+		//  GitHub-issue: #28
+	}
+}
+
 func (bc *BotController) handleTextState(m *tb.Message) {
 	tx := bc.State.Get(m)
 	if tx == nil {

db/crud/auth_user.go

@@ -2,6 +2,7 @@ package crud
 
 import (
 	"log"
+	"strconv"
 	"time"
 
 	tb "gopkg.in/tucnak/telebot.v2"
@@ -112,6 +113,63 @@ func (r *Repo) UserGetCurrency(m *tb.Message) string {
 	return DEFAULT_CURRENCY
 }
 
+func (r *Repo) UserIsAdmin(m *tb.Message) bool {
+	rows, err := r.db.Query(`
+		SELECT "isAdmin"
+		FROM "auth::user"
+		WHERE "tgChatId" = $1 AND "tgUserId" = "tgChatId" -- is a private chat
+	`, m.Chat.ID)
+	if err != nil {
+		log.Printf("Encountered error while getting user currency (user: %d): %s", m.Chat.ID, err.Error())
+	}
+	defer rows.Close()
+
+	isAdmin := false
+	if rows.Next() {
+		err = rows.Scan(&isAdmin)
+		if err != nil {
+			log.Printf("Encountered error while scanning user isAdmin into var (user: %d): %s", m.Chat.ID, err.Error())
+			return false
+		}
+	}
+	return isAdmin
+}
+
+func (r *Repo) IndividualsWithNotifications(myChatId int64, chatId string) (recipients []string) {
+	query := `
+		SELECT "tgChatId"
+		FROM "auth::user"
+		WHERE "tgUserId" = "tgChatId" -- is a private chat
+			AND "tgChatId" != $1
+	`
+	params := []interface{}{myChatId}
+
+	if chatId != "" {
+		i, err := strconv.ParseInt(chatId, 10, 64)
+		if err != nil {
+			log.Printf("Error while parsing chatId to int64: %s", err.Error())
+		}
+		query += `AND "tgChatId" = $2`
+		params = append(params, i)
+	}
+	rows, err := r.db.Query(query, params...)
+	if err != nil {
+		log.Printf("Encountered error while getting user currency: %s", err.Error())
+	}
+	defer rows.Close()
+
+	var rec string
+	if rows.Next() {
+		err = rows.Scan(&rec)
+		if err != nil {
+			log.Printf("Encountered error while scanning into var: %s", err.Error())
+			return []string{}
+		}
+		recipients = append(recipients, rec)
+	}
+	return
+}
+
 func (r *Repo) UserSetCurrency(m *tb.Message, currency string) error {
 	_, err := r.db.Exec(`
 		UPDATE "auth::user"

db/migrations/controller.go

@@ -13,6 +13,7 @@ func Migrate(db *sql.DB) {
 	migrationWrapper(v1, 1)(db)
 	migrationWrapper(v2, 2)(db)
 	migrationWrapper(v3, 3)(db)
+	migrationWrapper(v4, 4)(db)
 
 	fmt.Println("Migrations ran through. Schema version:", schema(db))
 }

db/migrations/v4.go

@@ -0,0 +1,21 @@
+package migrations
+
+import (
+	"database/sql"
+	"log"
+)
+
+func v4(db *sql.Tx) {
+	v4UserAdmin(db)
+}
+
+func v4UserAdmin(db *sql.Tx) {
+	sqlStatement := `
+	ALTER TABLE "auth::user"
+	ADD "isAdmin" BOOLEAN DEFAULT FALSE NOT NULL;
+	`
+	_, err := db.Exec(sqlStatement)
+	if err != nil {
+		log.Fatal(err)
+	}
+}