From 7b4c95678e202176e0bc5085db7b6d31a25f662d Mon Sep 17 00:00:00 2001
From: Gabriel De Los Rios <gab.dlr3012@gmail.com>
Date: Sun, 21 Dec 2025 20:06:18 -0300
Subject: [PATCH] feat; add multi language support

---
 .../components/contact-form/contact-form.html | 12 +--
 .../components/contact-form/contact-form.ts   |  4 +-
 .../contact-list-table.html                   |  8 +-
 .../contact-list-table/contact-list-table.ts  |  4 +-
 .../components/contact-list/contact-list.html |  4 +-
 .../components/contact-list/contact-list.ts   |  4 +-
 .../contact-search-bar.html                   |  2 +-
 .../contact-search-bar/contact-search-bar.ts  |  9 ++-
 .../components/notification/notification.html |  2 +-
 .../components/notification/notification.ts   |  3 +-
 .../name-and-company-field.ts                 |  8 +-
 src/app/errors-dictionaries/phone-field.ts    |  8 +-
 src/app/pages/edit/contact-resolver.spec.ts   |  3 +
 src/app/pages/edit/edit.html                  |  8 +-
 src/app/pages/edit/edit.ts                    |  4 +-
 src/app/pages/main/main.html                  |  8 +-
 src/app/pages/main/main.ts                    |  4 +-
 src/app/services/contact.service.spec.ts      |  8 +-
 src/app/services/contact.service.ts           | 16 ++--
 src/app/services/language-manager.spec.ts     | 27 +++++++
 src/app/services/language-manager.ts          | 16 ++++
 src/app/strings.ts                            | 75 +++++++++++++------
 src/app/types/Language.type.ts                |  3 +
 23 files changed, 163 insertions(+), 77 deletions(-)
 create mode 100644 src/app/services/language-manager.spec.ts
 create mode 100644 src/app/services/language-manager.ts
 create mode 100644 src/app/types/Language.type.ts

diff --git a/src/app/components/contact-form/contact-form.html b/src/app/components/contact-form/contact-form.html
index 341d887..42c2ada 100644
--- a/src/app/components/contact-form/contact-form.html
+++ b/src/app/components/contact-form/contact-form.html
@@ -5,20 +5,20 @@
         <app-form-field 
             [errorsDictionary]="companyAndNameErrorsDictionary"
             formControlName="name"
-            [label]="(strings.name|upperfirst) + ':'"
-            [placeholder]="strings.contactsName|upperfirst"
+            [label]="(languageManager.strings.name|upperfirst) + ':'"
+            [placeholder]="languageManager.strings.contactsName|upperfirst"
         />
         <app-form-field 
             [errorsDictionary]="companyAndNameErrorsDictionary"
             formControlName="company"
-            [label]="(strings.company|upperfirst) + ':'"
-            [placeholder]="strings.contactsCompany|upperfirst"
+            [label]="(languageManager.strings.company|upperfirst) + ':'"
+            [placeholder]="languageManager.strings.contactsCompany|upperfirst"
         />
         <app-form-field
             [errorsDictionary]="phoneErrorsDictionary"
             formControlName="phone"
-            [label]="(strings.phone|upperfirst) +':'"
-            [placeholder]="strings.contactsPhone|upperfirst"
+            [label]="(languageManager.strings.phone|upperfirst) +':'"
+            [placeholder]="languageManager.strings.contactsPhone|upperfirst"
             type="tel"
         />
     </div>
diff --git a/src/app/components/contact-form/contact-form.ts b/src/app/components/contact-form/contact-form.ts
index c66fbbf..2db682a 100644
--- a/src/app/components/contact-form/contact-form.ts
+++ b/src/app/components/contact-form/contact-form.ts
@@ -1,7 +1,6 @@
 import { Component, inject, input, output } from '@angular/core';
 import { ReactiveFormsModule } from '@angular/forms';
 import { FormField } from '../form-field/form-field';
-import { STRINGS_INJECTOR } from '../../app.config';
 import { SquaredBtn } from '../squared-btn/squared-btn';
 import { NameAndCompanyFieldsErrorsDictionary } from '../../errors-dictionaries/name-and-company-field';
 import { PhoneFieldErroresDictionary } from '../../errors-dictionaries/phone-field';
@@ -9,6 +8,7 @@ import { UpperfirstPipe } from '../../pipes/upperfirst-pipe';
 import { ContactDTO } from '../../models/ContactDTO';
 import { ContactFormValue } from '../../types/ContactFormValue.type';
 import { FormGroupContact } from '../../utils/form-group-contact';
+import { LanguageManager } from '../../services/language-manager';
 
 @Component({
   selector: 'app-contact-form',
@@ -20,7 +20,7 @@ export class ContactForm {
   contact = output<ContactDTO>();
   form = input(new FormGroupContact());
   submitText = input('');
-  protected strings = inject(STRINGS_INJECTOR);
+  protected languageManager = inject(LanguageManager);
   protected companyAndNameErrorsDictionary =
     new NameAndCompanyFieldsErrorsDictionary().getDictionary();
   protected phoneErrorsDictionary = new PhoneFieldErroresDictionary().getDictionary();
diff --git a/src/app/components/contact-list-table/contact-list-table.html b/src/app/components/contact-list-table/contact-list-table.html
index e3c452c..1e36b9f 100644
--- a/src/app/components/contact-list-table/contact-list-table.html
+++ b/src/app/components/contact-list-table/contact-list-table.html
@@ -2,10 +2,10 @@
 <table class="contact-list">
     <thead>
         <tr>
-            <th>{{strings.name}}</th>
-            <th>{{strings.company}}</th> 
-            <th>{{strings.phone}}</th> 
-            <th>{{strings.actions}}</th>   
+            <th>{{languageManager.strings.name}}</th>
+            <th>{{languageManager.strings.company}}</th> 
+            <th>{{languageManager.strings.phone}}</th> 
+            <th>{{languageManager.strings.actions}}</th>   
         </tr>
     </thead>
     <tbody>
diff --git a/src/app/components/contact-list-table/contact-list-table.ts b/src/app/components/contact-list-table/contact-list-table.ts
index faee43c..d912db0 100644
--- a/src/app/components/contact-list-table/contact-list-table.ts
+++ b/src/app/components/contact-list-table/contact-list-table.ts
@@ -1,9 +1,9 @@
 import { Component, inject, input } from '@angular/core';
-import { STRINGS_INJECTOR } from '../../app.config';
 import { ContactDTO } from '../../models/ContactDTO';
 import { ContactActionsBar } from '../contact-actions-bar/contact-actions-bar';
 import { ContactService } from '../../services/contact.service';
 import { Router } from '@angular/router';
+import { LanguageManager } from '../../services/language-manager';
 
 @Component({
   selector: 'app-contact-list-table',
@@ -13,7 +13,7 @@ import { Router } from '@angular/router';
 })
 export class ContactListTable {
   contactList = input<ContactDTO[]>([]);
-  protected readonly strings = inject(STRINGS_INJECTOR);
+  protected readonly languageManager = inject(LanguageManager);
   private readonly contactService = inject(ContactService);
   private readonly router = inject(Router);
 
diff --git a/src/app/components/contact-list/contact-list.html b/src/app/components/contact-list/contact-list.html
index f342901..21196b2 100644
--- a/src/app/components/contact-list/contact-list.html
+++ b/src/app/components/contact-list/contact-list.html
@@ -1,10 +1,10 @@
 <div class="contact-list">
     <div class="contact-list__container">
-        <h2>{{strings.contacts|upperfirst}}</h2>
+        <h2>{{languageManager.strings.contacts|upperfirst}}</h2>
         <app-contact-search-bar (contactSearch)="filter=$event"/>
         <app-counter 
             [count]="(this.contacts$|async)?.length ?? 0"
-            item="{{strings.contacts}}"
+            item="{{languageManager.strings.contacts}}"
         />
         <app-contact-list-table [contactList]="(this.contacts$|async)|contactsFilter:filter"/>
     </div>
diff --git a/src/app/components/contact-list/contact-list.ts b/src/app/components/contact-list/contact-list.ts
index b71cf50..092dfec 100644
--- a/src/app/components/contact-list/contact-list.ts
+++ b/src/app/components/contact-list/contact-list.ts
@@ -1,5 +1,4 @@
 import { Component, inject, OnInit } from '@angular/core';
-import { STRINGS_INJECTOR } from '../../app.config';
 import { UpperfirstPipe } from '../../pipes/upperfirst-pipe';
 import { ContactSearchBar } from '../contact-search-bar/contact-search-bar';
 import { ContactListTable } from '../contact-list-table/contact-list-table';
@@ -7,6 +6,7 @@ import { ContactService } from '../../services/contact.service';
 import { AsyncPipe } from '@angular/common';
 import { Counter } from '../counter/counter';
 import { ContactsFilterPipe } from '../../pipes/contacts-filter-pipe';
+import { LanguageManager } from '../../services/language-manager';
 
 @Component({
   selector: 'app-contact-list',
@@ -23,7 +23,7 @@ import { ContactsFilterPipe } from '../../pipes/contacts-filter-pipe';
 })
 export class ContactList implements OnInit {
   private readonly contactService = inject(ContactService);
-  protected readonly strings = inject(STRINGS_INJECTOR);
+  protected readonly languageManager = inject(LanguageManager);
   protected contacts$ = this.contactService.contacts$;
   protected filter = '';
 
diff --git a/src/app/components/contact-search-bar/contact-search-bar.html b/src/app/components/contact-search-bar/contact-search-bar.html
index 83b3e49..adf7c94 100644
--- a/src/app/components/contact-search-bar/contact-search-bar.html
+++ b/src/app/components/contact-search-bar/contact-search-bar.html
@@ -1,5 +1,5 @@
 <input 
     (input)="contactSearch.emit($event.target.value)" 
     class="search-bar shadow"
-    placeholder="{{strings.searchContactPlaceholder}}" 
+    placeholder="{{languageManager.strings.searchContactPlaceholder|upperfirst}}" 
     type="text">
\ No newline at end of file
diff --git a/src/app/components/contact-search-bar/contact-search-bar.ts b/src/app/components/contact-search-bar/contact-search-bar.ts
index 5645058..83b4c5d 100644
--- a/src/app/components/contact-search-bar/contact-search-bar.ts
+++ b/src/app/components/contact-search-bar/contact-search-bar.ts
@@ -1,13 +1,14 @@
 import { Component, inject, output } from '@angular/core';
-import { STRINGS_INJECTOR } from '../../app.config';
+import { LanguageManager } from '../../services/language-manager';
+import { UpperfirstPipe } from '../../pipes/upperfirst-pipe';
 
 @Component({
   selector: 'app-contact-search-bar',
-  imports: [],
+  imports: [UpperfirstPipe],
   templateUrl: './contact-search-bar.html',
   styleUrl: './contact-search-bar.scss',
 })
 export class ContactSearchBar {
-  contactSearch = output<string>()
-  protected readonly strings = inject(STRINGS_INJECTOR);
+  contactSearch = output<string>();
+  protected readonly languageManager = inject(LanguageManager);
 }
diff --git a/src/app/components/notification/notification.html b/src/app/components/notification/notification.html
index 93256e0..4eb5710 100644
--- a/src/app/components/notification/notification.html
+++ b/src/app/components/notification/notification.html
@@ -1,6 +1,6 @@
 @if(notification$(); as notification) {
     <div class="notification notification--{{notification.type}} notification--fade-in-out">
-        <p>{{ notification.message  }}</p>
+        <p>{{ notification.message|upperfirst  }}</p>
     </div>
 }
 
diff --git a/src/app/components/notification/notification.ts b/src/app/components/notification/notification.ts
index 488c161..f0814ad 100644
--- a/src/app/components/notification/notification.ts
+++ b/src/app/components/notification/notification.ts
@@ -1,9 +1,10 @@
 import { Component, inject } from '@angular/core';
 import { Notifier } from '../../services/notifier';
+import { UpperfirstPipe } from '../../pipes/upperfirst-pipe';
 
 @Component({
   selector: 'app-notification',
-  imports: [],
+  imports: [UpperfirstPipe],
   templateUrl: './notification.html',
   styleUrl: './notification.scss',
 })
diff --git a/src/app/errors-dictionaries/name-and-company-field.ts b/src/app/errors-dictionaries/name-and-company-field.ts
index 3087467..ce4da5c 100644
--- a/src/app/errors-dictionaries/name-and-company-field.ts
+++ b/src/app/errors-dictionaries/name-and-company-field.ts
@@ -1,14 +1,14 @@
 import { inject } from '@angular/core';
 import { Dictionary } from '../interfaces/dictionary.interface';
-import { STRINGS_INJECTOR } from '../app.config';
+import { LanguageManager } from '../services/language-manager';
 
 export class NameAndCompanyFieldsErrorsDictionary implements Dictionary {
-  private readonly strings = inject(STRINGS_INJECTOR);
+  private readonly languageManager = inject(LanguageManager);
   private readonly maxlen: string;
-  private readonly required = this.strings.errorMessageRequired;
+  private readonly required = this.languageManager.strings.errorMessageRequired;
 
   constructor() {
-    this.maxlen = this.strings.errorMessageMaxLength(120);
+    this.maxlen = this.languageManager.strings.errorMessageMaxLength(120);
   }
 
   getDictionary(): { [key: string]: string } {
diff --git a/src/app/errors-dictionaries/phone-field.ts b/src/app/errors-dictionaries/phone-field.ts
index 0bddeea..b283f22 100644
--- a/src/app/errors-dictionaries/phone-field.ts
+++ b/src/app/errors-dictionaries/phone-field.ts
@@ -1,11 +1,11 @@
 import { inject } from '@angular/core';
 import { Dictionary } from '../interfaces/dictionary.interface';
-import { STRINGS_INJECTOR } from '../app.config';
+import { LanguageManager } from '../services/language-manager';
 
 export class PhoneFieldErroresDictionary implements Dictionary {
-  strings = inject(STRINGS_INJECTOR);
-  pattern = this.strings.errorMessagePhonePattern;
-  required = this.strings.errorMessageRequired;
+  languageManager = inject(LanguageManager);
+  pattern = this.languageManager.strings.errorMessagePhonePattern;
+  required = this.languageManager.strings.errorMessageRequired;
 
   getDictionary(): { [key: string]: string } {
     const { required, pattern } = this;
diff --git a/src/app/pages/edit/contact-resolver.spec.ts b/src/app/pages/edit/contact-resolver.spec.ts
index 8dc84a8..f3ab2cf 100644
--- a/src/app/pages/edit/contact-resolver.spec.ts
+++ b/src/app/pages/edit/contact-resolver.spec.ts
@@ -6,6 +6,8 @@ import { ContactDTO } from '../../models/ContactDTO';
 import { provideHttpClient } from '@angular/common/http';
 import { HttpTestingController, provideHttpClientTesting } from '@angular/common/http/testing';
 import { environment } from '../../../environments/environment';
+import { STRINGS_INJECTOR } from '../../app.config';
+import { strings } from '../../strings';
 
 describe('contactResolver', () => {
   let httpTestingController: HttpTestingController;
@@ -31,6 +33,7 @@ describe('contactResolver', () => {
         provideHttpClient(),
         provideHttpClientTesting(),
         { provide: Router, useValue: router },
+        { provide: STRINGS_INJECTOR, useValue: strings },
       ],
     });
     httpTestingController = TestBed.inject(HttpTestingController);
diff --git a/src/app/pages/edit/edit.html b/src/app/pages/edit/edit.html
index e65a556..2dccab3 100644
--- a/src/app/pages/edit/edit.html
+++ b/src/app/pages/edit/edit.html
@@ -1,11 +1,11 @@
 <app-main-header
-    [title]="strings.editContact"
+    [title]="languageManager.strings.editContact"
 >
     <app-rounded-btn
         (keydown)="goBack()"  
         (click)="goBack()"
         slot="action-button"
-        text="Go back"
+        text={{languageManager.strings.goBack|upperfirst}}
     />
 </app-main-header>
 <app-card bgColor="var(--secondary)">
@@ -14,9 +14,9 @@
             class="form" 
             (contact)="edit(form.value)"
             [form]="form"
-            [submitText]="strings.save"
+            [submitText]="languageManager.strings.save"
         ><app-form-header 
-                [title]="strings.editTheContact|upperfirst" 
+                [title]="languageManager.strings.editTheContact|upperfirst" 
                 slot="header"
             />
         </app-contact-form>
diff --git a/src/app/pages/edit/edit.ts b/src/app/pages/edit/edit.ts
index 2cdaebb..223e7d7 100644
--- a/src/app/pages/edit/edit.ts
+++ b/src/app/pages/edit/edit.ts
@@ -1,6 +1,5 @@
 import { Component, inject } from '@angular/core';
 import { MainHeader } from '../../components/main-header/main-header';
-import { STRINGS_INJECTOR } from '../../app.config';
 import { RoundedBtn } from '../../components/rounded-btn/rounded-btn';
 import { ActivatedRoute, Router } from '@angular/router';
 import { Card } from '../../components/card/card';
@@ -13,6 +12,7 @@ import { FormGroupContact } from '../../utils/form-group-contact';
 import { AsyncPipe } from '@angular/common';
 import { ContactService } from '../../services/contact.service';
 import { ContactFormValue } from '../../types/ContactFormValue.type';
+import { LanguageManager } from '../../services/language-manager';
 
 @Component({
   selector: 'app-edit',
@@ -21,7 +21,7 @@ import { ContactFormValue } from '../../types/ContactFormValue.type';
   styleUrl: './edit.scss',
 })
 export class Edit {
-  protected readonly strings = inject(STRINGS_INJECTOR);
+  protected readonly languageManager = inject(LanguageManager);
   private readonly activatedRoute = inject(ActivatedRoute);
   private readonly contactService = inject(ContactService);
   private readonly router = inject(Router);
diff --git a/src/app/pages/main/main.html b/src/app/pages/main/main.html
index 2cde2ad..9f6dc41 100644
--- a/src/app/pages/main/main.html
+++ b/src/app/pages/main/main.html
@@ -1,13 +1,13 @@
-<app-main-header [title]="strings.contactList"/>
+<app-main-header [title]="languageManager.strings.contactAgenda"/>
 <app-card bgColor="var(--secondary)">
     <app-contact-form 
         (contact)="save($event)"
         [form]="form"
-        [submitText]="strings.add"
+        [submitText]="languageManager.strings.add"
         class="form" 
     ><app-form-header 
-            [subtitle]="strings.allFieldRequired|upperfirst"
-            [title]="strings.addContact|upperfirst" 
+            [subtitle]="languageManager.strings.allFieldRequired|upperfirst"
+            [title]="languageManager.strings.addContact|upperfirst" 
             slot="header"
         />
     </app-contact-form>
diff --git a/src/app/pages/main/main.ts b/src/app/pages/main/main.ts
index 4d088f0..e1623e5 100644
--- a/src/app/pages/main/main.ts
+++ b/src/app/pages/main/main.ts
@@ -5,10 +5,10 @@ import { ContactList } from '../../components/contact-list/contact-list';
 import { ContactService } from '../../services/contact.service';
 import { ContactDTO } from '../../models/ContactDTO';
 import { FormHeader } from '../../components/form-header/form-header';
-import { STRINGS_INJECTOR } from '../../app.config';
 import { UpperfirstPipe } from '../../pipes/upperfirst-pipe';
 import { MainHeader } from '../../components/main-header/main-header';
 import { FormGroupContact } from '../../utils/form-group-contact';
+import { LanguageManager } from '../../services/language-manager';
 
 @Component({
   selector: 'app-main',
@@ -18,7 +18,7 @@ import { FormGroupContact } from '../../utils/form-group-contact';
 })
 export class Main {
   protected readonly form = new FormGroupContact();
-  protected readonly strings = inject(STRINGS_INJECTOR);
+  protected readonly languageManager = inject(LanguageManager);
   private readonly contactService = inject(ContactService);
 
   save(contactDTO: ContactDTO) {
diff --git a/src/app/services/contact.service.spec.ts b/src/app/services/contact.service.spec.ts
index 40437aa..8b9ba7a 100644
--- a/src/app/services/contact.service.spec.ts
+++ b/src/app/services/contact.service.spec.ts
@@ -5,6 +5,8 @@ import { provideHttpClient } from '@angular/common/http';
 import { HttpTestingController, provideHttpClientTesting } from '@angular/common/http/testing';
 import { environment } from '../../environments/environment';
 import { ContactDTO } from '../models/ContactDTO';
+import { STRINGS_INJECTOR } from '../app.config';
+import { strings } from '../strings';
 
 describe('ContactService', () => {
   let service: ContactService;
@@ -16,7 +18,11 @@ describe('ContactService', () => {
   beforeEach(() => {
     TestBed.configureTestingModule({
       imports: [],
-      providers: [provideHttpClient(), provideHttpClientTesting()],
+      providers: [
+        provideHttpClient(),
+        provideHttpClientTesting(),
+        { provide: STRINGS_INJECTOR, useValue: strings },
+      ],
     });
     service = TestBed.inject(ContactService);
     httpTestingController = TestBed.inject(HttpTestingController);
diff --git a/src/app/services/contact.service.ts b/src/app/services/contact.service.ts
index 6b2143d..363747f 100644
--- a/src/app/services/contact.service.ts
+++ b/src/app/services/contact.service.ts
@@ -5,7 +5,7 @@ import { ContactDTO } from '../models/ContactDTO';
 import { Response } from '../models/Response';
 import { BehaviorSubject, map, switchMap, tap } from 'rxjs';
 import { ResponseStateNotification } from './ResponseStateNotificatio';
-import { strings } from '../strings';
+import { LanguageManager } from './language-manager';
 
 @Injectable({
   providedIn: 'root',
@@ -14,7 +14,7 @@ export class ContactService {
   private readonly httpClient = inject(HttpClient);
   private readonly responseStateNotification = inject(ResponseStateNotification);
   private readonly contacts = new BehaviorSubject<ContactDTO[]>([]);
-
+  private readonly languageManager = inject(LanguageManager);
   readonly contacts$ = this.contacts.asObservable();
 
   delete(id: number) {
@@ -22,8 +22,8 @@ export class ContactService {
       (r) =>
         this.responseStateNotification.handleResponse(
           r,
-          strings.deleteContactSuccessNotification,
-          strings.errorNotification
+          this.languageManager.strings.deleteContactSuccessNotification,
+          this.languageManager.strings.errorNotification
         ),
       switchMap(() => this.getAll())
     );
@@ -47,8 +47,8 @@ export class ContactService {
       (r) =>
         this.responseStateNotification.handleResponse(
           r,
-          strings.createContactSuccessNotification,
-          strings.errorNotification
+          this.languageManager.strings.createContactSuccessNotification,
+          this.languageManager.strings.errorNotification
         ),
 
       switchMap(() => this.getAll())
@@ -61,8 +61,8 @@ export class ContactService {
       .pipe((r) =>
         this.responseStateNotification.handleResponse(
           r,
-          strings.editContactSuccessNotification,
-          strings.errorNotification
+          this.languageManager.strings.editContactSuccessNotification,
+          this.languageManager.strings.errorNotification
         )
       );
   }
diff --git a/src/app/services/language-manager.spec.ts b/src/app/services/language-manager.spec.ts
new file mode 100644
index 0000000..13e6d8a
--- /dev/null
+++ b/src/app/services/language-manager.spec.ts
@@ -0,0 +1,27 @@
+import { TestBed } from '@angular/core/testing';
+
+import { LanguageManager } from './language-manager';
+import { strings } from '../strings';
+import { STRINGS_INJECTOR } from '../app.config';
+import { Language } from '../types/Language.type';
+
+describe('LanguageManager', () => {
+  let service: LanguageManager;
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      providers: [{ provide: STRINGS_INJECTOR, useValue: strings }],
+    });
+    service = TestBed.inject(LanguageManager);
+  });
+
+  it('should be created', () => {
+    expect(service).toBeTruthy();
+  });
+
+  it('should switch language', () => {
+    const SELECTED_LANGUAGE_MOCK: Language = 'es';
+    service.setLanguage(SELECTED_LANGUAGE_MOCK);
+    expect(service.strings).toEqual(strings[SELECTED_LANGUAGE_MOCK]);
+  });
+});
diff --git a/src/app/services/language-manager.ts b/src/app/services/language-manager.ts
new file mode 100644
index 0000000..42ad8c5
--- /dev/null
+++ b/src/app/services/language-manager.ts
@@ -0,0 +1,16 @@
+import { inject, Injectable } from '@angular/core';
+import { STRINGS_INJECTOR } from '../app.config';
+import { Language } from '../types/Language.type';
+
+@Injectable({
+  providedIn: 'root',
+})
+export class LanguageManager {
+  private readonly stringsDictionary = inject(STRINGS_INJECTOR);
+
+  strings = this.stringsDictionary.en;
+
+  setLanguage(language: Language) {
+    this.strings = this.stringsDictionary[language];
+  }
+}
diff --git a/src/app/strings.ts b/src/app/strings.ts
index 83470ca..a6ca68a 100644
--- a/src/app/strings.ts
+++ b/src/app/strings.ts
@@ -1,25 +1,54 @@
 export const strings = Object.freeze({
-  actions: 'actions',
-  add: 'add',
-  addContact: 'add a contact',
-  allFieldRequired: 'all fields are required',
-  company: 'company',
-  contacts: 'contacts',
-  contactsName: "Contact's name",
-  contactsCompany: "Contact's company",
-  contactsPhone: "Contact's phone",
-  contactList: 'contact list',
-  createContactSuccessNotification: 'Contact created successfully',
-  deleteContactSuccessNotification: 'Contact deleted successfully',
-  editContact: 'edit contact',
-  editContactSuccessNotification: 'Contact edited successfully',
-  editTheContact: 'edit the contact',
-  errorMessageMaxLength: (maxLen: number) => `Must be ${maxLen} characters or fewer.`,
-  errorMessagePhonePattern: `Valid format: + (optional) plus 12 to 15 digits`,
-  errorMessageRequired: 'This field is required.',
-  errorNotification: 'Oops, there was an error',
-  name: 'name',
-  phone: 'phone',
-  save: 'save',
-  searchContactPlaceholder: 'Search contact...',
+  en: {
+    actions: 'actions',
+    add: 'add',
+    addContact: 'add a contact',
+    allFieldRequired: 'all fields are required',
+    company: 'company',
+    contactAgenda: 'contact agenda',
+    contacts: 'contacts',
+    contactsName: "contact's name",
+    contactsCompany: "contact's company",
+    contactsPhone: "contact's phone",
+    createContactSuccessNotification: 'contact created successfully',
+    deleteContactSuccessNotification: 'contact deleted successfully',
+    editContact: 'edit contact',
+    editContactSuccessNotification: 'contact edited successfully',
+    editTheContact: 'edit the contact',
+    errorMessageMaxLength: (maxLen: number) => `Must be ${maxLen} characters or fewer.`,
+    errorMessagePhonePattern: `Valid format: + (optional) plus 12 to 15 digits`,
+    errorMessageRequired: 'This field is required.',
+    errorNotification: 'Oops, there was an error',
+    goBack: 'go back',
+    name: 'name',
+    phone: 'phone',
+    save: 'save',
+    searchContactPlaceholder: 'Search contact...',
+  },
+  es: {
+    actions: 'acciones',
+    add: 'añadir',
+    addContact: 'añada un contacto',
+    allFieldRequired: 'todos los campos son obligatorios',
+    company: 'empresa',
+    contactAgenda: 'agenda de contactos',
+    contacts: 'contactos',
+    contactsName: 'nombre contacto',
+    contactsCompany: 'empresa contacto',
+    contactsPhone: 'teléfono contacto',
+    createContactSuccessNotification: 'contacto creado correctamente',
+    deleteContactSuccessNotification: 'contacto eliminado',
+    editContact: 'editar contacto',
+    editContactSuccessNotification: 'contacto editado correctamente',
+    editTheContact: 'edite el contacto. ',
+    errorMessageMaxLength: (maxLen: number) => `Debe contener ${maxLen} caracteres or menos.`,
+    errorMessagePhonePattern: `Formato: + (opcional) y 12 a 15 digitos`,
+    errorMessageRequired: 'este campo es requerido.',
+    errorNotification: 'hubo un error',
+    goBack: 'volver',
+    name: 'nombre',
+    phone: 'teléfono',
+    save: 'guardar',
+    searchContactPlaceholder: 'buscar contactos...',
+  },
 });
diff --git a/src/app/types/Language.type.ts b/src/app/types/Language.type.ts
new file mode 100644
index 0000000..595dff2
--- /dev/null
+++ b/src/app/types/Language.type.ts
@@ -0,0 +1,3 @@
+import { strings } from '../strings';
+
+export type Language = keyof typeof strings;