[MM-43337] Updating email templates for trial will end and trial ended emails (#19976)

* Updating email templates for trial will end and trial will end emails

* put back variable

* Rebuilding

* fix tests

* Updates

* [MM-43339] Add Cloud Subscription Upgrade Confirmation Email (#19989)

* Add Cloud Upgrade Confirmation email

* Updates

* String change

* i18n-extract

* Updates

* make email-mocks

* Appease linter

* Add a test

* GMAIL NEVER RENDERS RIGHT

* Important EVERYWHERE because gmail just cant deal

* l

* Last one

* Update image

* Update tests

* Fix tests

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

app/cloud.go

@@ -4,7 +4,9 @@
 package app
 
 import (
+	"fmt"
 	"net/http"
+	"time"
 
 	"github.com/mattermost/mattermost-server/v6/model"
 	"github.com/mattermost/mattermost-server/v6/shared/mlog"
@@ -35,6 +37,50 @@ func (a *App) SendPaymentFailedEmail(failedPayment *model.FailedPayment) *model.
 	return nil
 }
 
+func (a *App) SendUpgradeConfirmationEmail() *model.AppError {
+	sysAdmins, e := a.getSysAdminsEmailRecipients()
+	if e != nil {
+		return e
+	}
+
+	if len(sysAdmins) == 0 {
+		return model.NewAppError("app.SendCloudUpgradeConfirmationEmail", "app.user.send_emails.app_error", nil, "", http.StatusInternalServerError)
+	}
+
+	subscription, err := a.Cloud().GetSubscription("")
+	if err != nil {
+		return model.NewAppError("app.SendCloudUpgradeConfirmationEmail", "app.user.send_emails.app_error", nil, "", http.StatusInternalServerError)
+	}
+
+	// Build readable trial end date
+	endTimeStamp := subscription.TrialEndAt
+	t := time.Unix(endTimeStamp, 0)
+	trialEndDate := fmt.Sprintf("%s %d, %d", t.Month(), t.Day(), t.Year())
+
+	// we want to at least have one email sent out to an admin
+	countNotOks := 0
+
+	for _, admin := range sysAdmins {
+		name := admin.FirstName
+		if name == "" {
+			name = admin.Username
+		}
+
+		err := a.Srv().EmailService.SendCloudUpgradeConfirmationEmail(admin.Email, name, trialEndDate, admin.Locale, *a.Config().ServiceSettings.SiteURL, subscription.GetWorkSpaceNameFromDNS())
+		if err != nil {
+			a.Log().Error("Error sending trial ended email to", mlog.String("email", admin.Email), mlog.Err(err))
+			countNotOks++
+		}
+	}
+
+	// if not even one admin got an email, we consider that this operation errored
+	if countNotOks == len(sysAdmins) {
+		return model.NewAppError("app.SendCloudUpgradeConfirmationEmail", "app.user.send_emails.app_error", nil, "", http.StatusInternalServerError)
+	}
+
+	return nil
+}
+
 // SendNoCardPaymentFailedEmail
 func (a *App) SendNoCardPaymentFailedEmail() *model.AppError {
 	sysAdmins, err := a.getSysAdminsEmailRecipients()