[PM-32237] Add back functionality to email OTP auth flow (#19024)

* add back functionality to OTP auth flow

* respond to review comments

* hoist email value to parent component

---------

Co-authored-by: Alex Dragovich <46065570+itsadrago@users.noreply.github.com>

apps/web/src/app/tools/send/send-access/send-access-email.component.html

@@ -20,16 +20,18 @@
     <bit-label>{{ "verificationCode" | i18n }}</bit-label>
     <input bitInput type="text" [formControl]="otp" required appInputVerbatim appAutofocus />
   </bit-form-field>
-  <div class="tw-flex">
-    <button
-      bitButton
-      bitFormButton
-      type="submit"
-      buttonType="primary"
-      [loading]="loading()"
-      [block]="true"
-    >
-      <span>{{ "viewSend" | i18n }} </span>
-    </button>
-  </div>
+  <button
+    bitButton
+    bitFormButton
+    type="submit"
+    buttonType="primary"
+    [loading]="loading()"
+    [block]="true"
+    class="tw-mb-3"
+  >
+    <span>{{ "viewSend" | i18n }} </span>
+  </button>
+  <button bitButton type="button" buttonType="secondary" [block]="true" (click)="onBackClick()">
+    <span>{{ "back" | i18n }}</span>
+  </button>
 }

apps/web/src/app/tools/send/send-access/send-access-email.component.ts

@@ -1,6 +1,14 @@
 // FIXME: Update this file to be type safe and remove this and next line
 // @ts-strict-ignore
-import { ChangeDetectionStrategy, Component, input, OnDestroy, OnInit } from "@angular/core";
+import {
+  ChangeDetectionStrategy,
+  Component,
+  effect,
+  input,
+  OnDestroy,
+  OnInit,
+  output,
+} from "@angular/core";
 import { FormControl, FormGroup, Validators } from "@angular/forms";
 
 import { SharedModule } from "../../../shared";
@@ -18,18 +26,45 @@ export class SendAccessEmailComponent implements OnInit, OnDestroy {
   protected otp: FormControl;
 
   readonly loading = input.required<boolean>();
+  readonly backToEmail = output<void>();
 
   constructor() {}
 
   ngOnInit() {
     this.email = new FormControl("", Validators.required);
-    this.otp = new FormControl("", Validators.required);
+    this.otp = new FormControl("");
     this.formGroup().addControl("email", this.email);
     this.formGroup().addControl("otp", this.otp);
-  }
 
+    // Update validators when enterOtp changes
+    effect(() => {
+      const isOtpMode = this.enterOtp();
+      if (isOtpMode) {
+        // In OTP mode: email is not required (already entered), otp is required
+        this.email.clearValidators();
+        this.otp.setValidators([Validators.required]);
+      } else {
+        // In email mode: email is required, otp is not required
+        this.email.setValidators([Validators.required]);
+        this.otp.clearValidators();
+      }
+      this.email.updateValueAndValidity();
+      this.otp.updateValueAndValidity();
+    });
+  }
   ngOnDestroy() {
     this.formGroup().removeControl("email");
     this.formGroup().removeControl("otp");
   }
+
+  onBackClick() {
+    this.backToEmail.emit();
+    if (this.otp) {
+      this.otp.clearValidators();
+      this.otp.setValue("");
+      this.otp.setErrors(null);
+      this.otp.markAsUntouched();
+      this.otp.markAsPristine();
+    }
+  }
 }

apps/web/src/app/tools/send/send-access/send-auth.component.html

@@ -31,6 +31,7 @@
           [formGroup]="sendAccessForm"
           [enterOtp]="enterOtp()"
           [loading]="loading()"
+          (backToEmail)="onBackToEmail()"
         ></app-send-access-email>
       }
     }

apps/web/src/app/tools/send/send-access/send-auth.component.ts

@@ -90,6 +90,11 @@ export class SendAuthComponent implements OnInit {
     this.loading.set(false);
   }
 
+  onBackToEmail() {
+    this.enterOtp.set(false);
+    this.updatePageTitle();
+  }
+
   private async attemptV1Access() {
     try {
       const accessRequest = new SendAccessRequest();
@@ -247,10 +252,12 @@ export class SendAuthComponent implements OnInit {
       if (this.enterOtp()) {
         this.anonLayoutWrapperDataService.setAnonLayoutWrapperData({
           pageTitle: { key: "enterTheCodeSentToYourEmail" },
+          pageSubtitle: this.sendAccessForm.value.email ?? null,
         });
       } else {
         this.anonLayoutWrapperDataService.setAnonLayoutWrapperData({
           pageTitle: { key: "verifyYourEmailToViewThisSend" },
+          pageSubtitle: null,
         });
       }
     } else if (authType === AuthType.Password) {