angular.json

@@ -31,7 +31,12 @@
             ],
             "styles": [
               "src/styles.scss"
+            ],
+            "stylePreprocessorOptions": {
+              "includePaths": [
+                "src/assets/styles"
               ]
+            }
           },
           "configurations": {
             "production": {

src/app/app.html

@@ -1,7 +1,11 @@
 <div class="app-container">
   <header class="app-header">
     <h1>Common Cents</h1>
-    <h2>The common sense expense tracker.</h2>
+    <div class="app-navigation">
+      @for (link of navLinks(); track link) {
+        <a matButton [href]="link.href">{{ link.text }}</a>
+      }
+    </div>
     <app-divider />
   </header>
 

src/app/app.routes.ts

@@ -1,6 +1,8 @@
 import { Routes } from '@angular/router';
 import { ExpensePage } from './pages/expenses/expense-page.component';
 import { HomePage } from './pages/home/home-page.component';
+import { MetadataPageComponent } from './pages/metadata/metadata-page.component';
+import { ReportsPageComponent } from './pages/reports/reports-page.component';
 
 export const routes: Routes = [
   {
@@ -10,5 +12,13 @@ export const routes: Routes = [
   {
     path: 'expenses',
     component: ExpensePage
+  },
+  {
+    path: 'metadata',
+    component: MetadataPageComponent
+  },
+  {
+    path: 'reports',
+    component: ReportsPageComponent
   }
 ];

src/app/app.scss

@@ -14,19 +14,13 @@
 }
 
 h1 {
-  font-size: 3.125rem;
+  font-size: 2.5rem;
   line-height: 100%;
   letter-spacing: -0.125rem;
-  font-weight: 500;
+  font-weight: 400;
   margin: 0;
-  font-family: sans-serif;
 }
 
-h2 {
-  font-size: 1.2rem;
-  line-height: 100%;
-  font-weight: 500;
-  margin: 0;
-  font-family: sans-serif;
-  font-style: italic;
+.app-navigation {
+  display: flex;
 }

src/app/app.ts

@@ -1,11 +1,36 @@
-import { Component } from '@angular/core';
+import { Component, signal } from '@angular/core';
 import { RouterOutlet } from '@angular/router';
-import { Divider } from './components/divider/divider';
+import { DividerComponent } from './components/divider/divider.component';
+import { MatButton } from '@angular/material/button';
+
+interface NavLink {
+  text: string;
+  href: string;
+}
 
 @Component({
   selector: 'app-root',
-  imports: [RouterOutlet, Divider],
+  imports: [RouterOutlet, DividerComponent, MatButton],
   templateUrl: './app.html',
   styleUrl: './app.scss'
 })
-export class App { }
+export class App {
+  public navLinks = signal<NavLink[]>([
+    {
+      text: 'Home',
+      href: '/'
+    },
+    {
+      text: 'Expenses',
+      href: '/expenses'
+    },
+    {
+      text: 'Metadata',
+      href: '/metadata'
+    },
+    {
+      text: 'Reports',
+      href: '/reports'
+    }
+  ]);
+}

src/app/components/divider/divider.component.ts

@@ -0,0 +1,9 @@
+import { Component } from '@angular/core';
+
+@Component({
+  selector: 'app-divider',
+  imports: [],
+  templateUrl: './divider.component.html',
+  styleUrl: './divider.component.scss'
+})
+export class DividerComponent { }

src/app/components/divider/divider.ts

@@ -1,9 +0,0 @@
-import { Component } from '@angular/core';
-
-@Component({
-  selector: 'app-divider',
-  imports: [],
-  templateUrl: './divider.html',
-  styleUrl: './divider.scss'
-})
-export class Divider { }

src/app/components/expense-list/expense-list.component.scss

@@ -12,9 +12,8 @@
   p {
     font-size: 1.8rem;
     line-height: 100%;
-    font-weight: 200;
+    font-weight: 400;
     margin: 0;
-    font-family: sans-serif;
   }
 
   app-divider {
@@ -25,5 +24,5 @@
 .expense-list {
   display: grid;
   gap: 1rem;
-  justify-content: center;
+  justify-content: stretch;
 }

src/app/components/expense-list/expense-list.component.ts

@@ -3,11 +3,11 @@ import { ExpenseService } from '../../services/expense.service';
 import { MatTableModule } from '@angular/material/table';
 import { MatCardModule } from '@angular/material/card';
 import { ExpenseComponent } from '../expense/expense.component';
-import {Divider} from '../divider/divider';
+import { DividerComponent } from '../divider/divider.component';
 
 @Component({
   selector: 'app-expense-list',
-  imports: [MatTableModule, MatCardModule, ExpenseComponent, Divider],
+  imports: [MatTableModule, MatCardModule, ExpenseComponent, DividerComponent],
   templateUrl: './expense-list.component.html',
   styleUrl: './expense-list.component.scss'
 })

src/app/components/expense/expense-form/expense-form.component.scss

@@ -1,3 +1,5 @@
+@use "variables";
+
 .expense-form-container {
   display: grid;
 
@@ -6,14 +8,14 @@
   }
 }
 
-@media (min-width: 550px) {
+@media (min-width: variables.$mid-screen) {
   .expense-form-container {
     grid-template-columns: 1fr 1fr;
     gap: 1rem;
   }
 }
 
-@media (min-width: 800px) {
+@media (min-width: variables.$wide-screen) {
   .expense-form-container {
     grid-template-columns: 1fr 1fr 1fr;
   }

src/app/components/expense/expense-form/expense-form.component.ts

@@ -48,13 +48,18 @@ export class ExpenseFormComponent implements OnInit {
               private readonly merchantService: MerchantService,
               private readonly tagService: TagService) {
     effect(() => {
+      const form = this.form().value();
       const valid = this.formValid();
       const dirty = this.formDirty();
-      const value = this.form().value();
+      const value = {
+        ...form,
+        merchant: Boolean(form.merchant) ? form.merchant : null,
+        note: Boolean(form.note) ? form.note : null
+      };
 
       this.valid.emit(valid);
       this.dirty.emit(dirty);
-      this.value.emit(value);
+      this.value.emit(value as ExpenseForm);
       this.lastDate.set(value.date);
     });
   }
@@ -98,8 +103,8 @@ export class ExpenseFormComponent implements OnInit {
         date: new Date(year, month, day),
         cents: expense.cents,
         category: expense.category,
-        merchant: expense.merchant ?? {},
-        note: expense.note ?? '',
+        merchant: expense.merchant ?? null,
+        note: expense.note,
         tags: expense.tags ?? []
       } as ExpenseForm;
     }

src/app/components/expense/expense.component.scss

@@ -1,3 +1,5 @@
+@use "variables";
+
 .expense-container {
   width: 100%;
   display: flex;
@@ -5,7 +7,7 @@
   align-items: center;
 
   mat-card {
-    max-width: 800px;
+    max-width: variables.$wide-screen;
     width: 100%;
   }
 }

src/app/components/expense/expense.component.ts

@@ -38,15 +38,16 @@ export class ExpenseComponent {
     const postExpense: CreateExpense = {
       date: this.dateToPlainDate(form.date),
       cents: form.cents,
-      categoryId: form.category.id,
-      note: !!form.note ? form.note : undefined,
-      merchantId: !!form.merchant ? form.merchant.id : undefined,
-      tagIds: form.tags.map(tag => tag.id)
+      category: form.category,
+      merchant: form.merchant,
+      note: form.note,
+      tags: form.tags
     };
     this.savingExpense.set(true);
     const snackId = this.snackBar.staticBar('Tracking new expense...');
     try {
-      await this.expenseService.postExpense(postExpense);
+      await this.expenseService.create(postExpense);
+      await this.expenseService.fetch();
       this.resetForm();
       this.snackBar.dismiss(snackId);
       this.snackBar.autoBar('Expense tracked!');
@@ -70,15 +71,15 @@ export class ExpenseComponent {
       id: this.expense()!.id,
       date: this.dateToPlainDate(form.date),
       cents: form.cents,
-      categoryId: form.category.id,
-      note: !!form.note ? form.note : undefined,
-      merchantId: !!form.merchant ? form.merchant.id : undefined,
-      tagIds: form.tags.map(tag => tag.id)
+      category: form.category,
+      merchant: form.merchant,
+      note: form.note,
+      tags: form.tags
     };
     this.savingExpense.set(true);
     const snackId = this.snackBar.staticBar('Updating expense...');
     try {
-      const expense = await this.expenseService.updateExpense(putExpense);
+      const expense = await this.expenseService.update(putExpense);
       this.expense.set(expense);
       this.form()?.refresh(expense);
       this.editingExpense.set(false);

src/app/components/metadata/categories/categories.component.html

@@ -0,0 +1,24 @@
+<div class="categories-container">
+  <mat-card appearance="outlined">
+    <mat-card-header>
+      <mat-card-title>Categories</mat-card-title>
+    </mat-card-header>
+
+    <mat-card-content>
+      <div class="new-category">
+        <app-metadata-form (newMetaData)="createCategory($event.name)" [editing]="true" [label]="'New Category'"/>
+      </div>
+
+      <div class="category-list">
+        @for (category of categories(); track category.id) {
+          <app-metadata-form [metadata]="category" (newMetaData)="updateCategory($event)" />
+        }
+        @if (!categories().length) {
+          <div>
+            No categories to display
+          </div>
+        }
+      </div>
+    </mat-card-content>
+  </mat-card>
+</div>

src/app/components/metadata/categories/categories.component.scss

@@ -0,0 +1,21 @@
+@use "variables";
+
+.categories-container {
+  padding-top: 0.5rem;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+
+  mat-card {
+    max-width: variables.$wide-screen;
+    width: 100%;
+  }
+}
+
+.new-category {
+  padding-top: 0.5rem;
+}
+
+.category-list {
+  display: grid;
+}

src/app/components/metadata/categories/categories.component.ts

@@ -0,0 +1,29 @@
+import { Component, computed } from '@angular/core';
+import { Category, CategoryService } from '../../../services/category.service';
+import { MatCardModule } from '@angular/material/card';
+import { MetadataFormComponent } from '../metadata-form/metadata-form.component';
+
+@Component({
+  selector: 'app-categories',
+  imports: [
+    MatCardModule,
+    MetadataFormComponent
+  ],
+  templateUrl: './categories.component.html',
+  styleUrl: './categories.component.scss'
+})
+export class CategoriesComponent {
+  protected categories = computed(() => this.categoryService.categories());
+
+  public constructor(private readonly categoryService: CategoryService) { }
+
+  public async createCategory(name: string): Promise<void> {
+    await this.categoryService.create({ name });
+    await this.categoryService.fetch();
+  }
+
+  public async updateCategory(category: Category): Promise<void> {
+    await this.categoryService.update(category);
+    await this.categoryService.fetch();
+  }
+}

src/app/components/metadata/merchants/merchants.component.html

@@ -0,0 +1,24 @@
+<div class="merchants-container">
+  <mat-card appearance="outlined">
+    <mat-card-header>
+      <mat-card-title>Merchants</mat-card-title>
+    </mat-card-header>
+
+    <mat-card-content>
+      <div class="new-merchant">
+        <app-metadata-form (newMetaData)="createMerchant($event.name)" [editing]="true" [label]="'New Merchant'"/>
+      </div>
+
+      <div class="merchant-list">
+        @for (merchant of merchants(); track merchant.id) {
+          <app-metadata-form [metadata]="merchant" (newMetaData)="updateMerchant($event)" />
+        }
+        @if (!merchants().length) {
+          <div>
+            No merchants to display
+          </div>
+        }
+      </div>
+    </mat-card-content>
+  </mat-card>
+</div>

src/app/components/metadata/merchants/merchants.component.scss

@@ -0,0 +1,21 @@
+@use "variables";
+
+.merchants-container {
+  padding-top: 0.5rem;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+
+  mat-card {
+    max-width: variables.$wide-screen;
+    width: 100%;
+  }
+}
+
+.new-merchant {
+  padding-top: 0.5rem;
+}
+
+.merchant-list {
+  display: grid;
+}

src/app/components/metadata/merchants/merchants.component.ts

@@ -0,0 +1,29 @@
+import { Component, computed } from '@angular/core';
+import { Merchant, MerchantService } from '../../../services/merchant.service';
+import { MatCardModule } from '@angular/material/card';
+import { MetadataFormComponent } from '../metadata-form/metadata-form.component';
+
+@Component({
+  selector: 'app-merchants',
+  imports: [
+    MatCardModule,
+    MetadataFormComponent
+  ],
+  templateUrl: './merchants.component.html',
+  styleUrl: './merchants.component.scss'
+})
+export class MerchantsComponent {
+  protected merchants = computed(() => this.merchantService.merchants());
+
+  public constructor(private readonly merchantService: MerchantService) { }
+
+  public async createMerchant(name: string): Promise<void> {
+    await this.merchantService.create({ name });
+    await this.merchantService.fetch();
+  }
+
+  public async updateMerchant(merchant: Merchant): Promise<void> {
+    await this.merchantService.update(merchant);
+    await this.merchantService.fetch();
+  }
+}

src/app/components/metadata/metadata-form/metadata-form.component.html

@@ -0,0 +1,28 @@
+<div class="metadata-form-container">
+  @if (!editing()) {
+    <div>{{ metadata()?.name }}</div>
+
+    <button matIconButton (click)="editing.set(true)">
+      <mat-icon>edit</mat-icon>
+    </button>
+  } @else {
+    <div class="metadata-edit">
+      <mat-form-field appearance="outline">
+        @if (label()) {
+          <mat-label>{{ label() }}</mat-label>
+        }
+        <input type="text" matInput [(ngModel)]="name">
+      </mat-form-field>
+
+      <div class="metadata-edit-buttons">
+        <button matIconButton (click)="reset()">
+          <mat-icon>undo</mat-icon>
+        </button>
+
+        <button matIconButton (click)="saveMetaData()" [disabled]="!nameValid()">
+          <mat-icon>save</mat-icon>
+        </button>
+      </div>
+    </div>
+  }
+</div>

src/app/components/metadata/metadata-form/metadata-form.component.scss

@@ -0,0 +1,16 @@
+.metadata-form-container {
+  display: flex;
+  gap: 0.5rem;
+  align-items: center;
+}
+
+.metadata-edit {
+  display: flex;
+  gap: 0.5rem;
+
+  .metadata-edit-buttons {
+    padding-top: 0.5rem;
+    display: flex;
+    gap: 0.5rem;
+  }
+}

src/app/components/metadata/metadata-form/metadata-form.component.ts

@@ -0,0 +1,53 @@
+import { Component, computed, input, model, OnInit, output } from '@angular/core';
+import { MatIconModule } from '@angular/material/icon';
+import { MatButtonModule } from '@angular/material/button';
+import { MatInputModule } from '@angular/material/input';
+import { FormsModule } from '@angular/forms';
+
+interface MetaData {
+  id: string;
+  name: string;
+}
+
+@Component({
+  selector: 'app-metadata-form',
+  imports: [
+    MatIconModule,
+    MatButtonModule,
+    MatInputModule,
+    FormsModule,
+  ],
+  templateUrl: './metadata-form.component.html',
+  styleUrl: './metadata-form.component.scss'
+})
+export class MetadataFormComponent implements OnInit {
+  public editing = model(false);
+  public label = input<string>();
+  public metadata = input<MetaData>();
+  public newMetaData = output<MetaData>();
+
+  public name = model('');
+  public nameValid = computed(() => {
+    const existingName = this.metadata()?.name;
+    const newName = this.name();
+
+    return !!newName && newName !== existingName;
+  });
+
+  public ngOnInit(): void {
+    this.reset();
+  }
+
+  public saveMetaData(): void {
+    this.newMetaData.emit({
+      ...this.metadata()!,
+      name: this.name()
+    });
+    this.reset();
+  }
+
+  public reset(): void {
+    this.name.set(this.metadata()?.name ?? '');
+    this.editing.set(!this.metadata());
+  }
+}

src/app/components/metadata/metadata.component.html

@@ -0,0 +1,36 @@
+<div class="metadata-container">
+  <mat-tab-group>
+    <mat-tab>
+      <ng-template mat-tab-label>
+        <div class="metadata-tab">
+          <div class="tab-text">Categories</div>
+          <mat-icon class="material-icons-outlined">dashboard</mat-icon>
+        </div>
+      </ng-template>
+
+      <app-categories />
+    </mat-tab>
+
+    <mat-tab>
+      <ng-template mat-tab-label>
+        <div class="metadata-tab">
+          <div class="tab-text">Merchants</div>
+          <mat-icon class="material-icons-outlined">shopping_cart</mat-icon>
+        </div>
+      </ng-template>
+
+      <app-merchants />
+    </mat-tab>
+
+    <mat-tab>
+      <ng-template mat-tab-label>
+        <div class="metadata-tab">
+          <div class="tab-text">Tags</div>
+          <mat-icon class="material-icons-outlined">sell</mat-icon>
+        </div>
+      </ng-template>
+
+      <app-tags />
+    </mat-tab>
+  </mat-tab-group>
+</div>

src/app/components/metadata/metadata.component.scss

@@ -0,0 +1,17 @@
+@use "variables";
+
+.metadata-tab {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+}
+
+.tab-text {
+  display: none;
+}
+
+@media (min-width: variables.$mid-screen) {
+  .tab-text {
+    display: unset;
+  }
+}

src/app/components/metadata/metadata.component.ts

@@ -0,0 +1,22 @@
+import { Component } from '@angular/core';
+import { MatTab, MatTabGroup, MatTabLabel } from '@angular/material/tabs';
+import { MatIcon } from '@angular/material/icon';
+import { TagsComponent } from './tags/tags.component';
+import { MerchantsComponent } from './merchants/merchants.component';
+import { CategoriesComponent } from './categories/categories.component';
+
+@Component({
+  selector: 'app-metadata',
+  imports: [
+    MatTabGroup,
+    MatTab,
+    MatIcon,
+    MatTabLabel,
+    TagsComponent,
+    MerchantsComponent,
+    CategoriesComponent
+  ],
+  templateUrl: './metadata.component.html',
+  styleUrl: './metadata.component.scss'
+})
+export class MetadataComponent { }

src/app/components/metadata/tags/tags.component.html

@@ -0,0 +1,24 @@
+<div class="tags-container">
+  <mat-card appearance="outlined">
+    <mat-card-header>
+      <mat-card-title>Tags</mat-card-title>
+    </mat-card-header>
+
+    <mat-card-content>
+      <div class="new-tag">
+        <app-metadata-form (newMetaData)="createTag($event.name)" [editing]="true" [label]="'New Tag'"/>
+      </div>
+
+      <div class="tag-list">
+        @for (tag of tags(); track tag.id) {
+          <app-metadata-form [metadata]="tag" (newMetaData)="updateTag($event)" />
+        }
+        @if (!tags().length) {
+          <div>
+            No tags to display
+          </div>
+        }
+      </div>
+    </mat-card-content>
+  </mat-card>
+</div>

src/app/components/metadata/tags/tags.component.scss

@@ -0,0 +1,21 @@
+@use "variables";
+
+.tags-container {
+  padding-top: 0.5rem;
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+
+  mat-card {
+    max-width: variables.$wide-screen;
+    width: 100%;
+  }
+}
+
+.new-tag {
+  padding-top: 0.5rem;
+}
+
+.tag-list {
+  display: grid;
+}

src/app/components/metadata/tags/tags.component.ts

@@ -0,0 +1,29 @@
+import { Component, computed } from '@angular/core';
+import { Tag, TagService } from '../../../services/tag.service';
+import { MatCardModule } from '@angular/material/card';
+import { MetadataFormComponent } from '../metadata-form/metadata-form.component';
+
+@Component({
+  selector: 'app-tags',
+  imports: [
+    MatCardModule,
+    MetadataFormComponent
+  ],
+  templateUrl: './tags.component.html',
+  styleUrl: './tags.component.scss'
+})
+export class TagsComponent {
+  protected tags = computed(() => this.tagService.tags());
+
+  public constructor(private readonly tagService: TagService) { }
+
+  public async createTag(name: string): Promise<void> {
+    await this.tagService.create({ name });
+    await this.tagService.fetch();
+  }
+
+  public async updateTag(tag: Tag): Promise<void> {
+    await this.tagService.update(tag);
+    await this.tagService.fetch();
+  }
+}

src/app/pages/expenses/expense-page.component.html

@@ -1,4 +1,4 @@
-<div class="expenses-container">
+<div class="expenses-page-container">
   <app-expense />
   <app-expense-list />
 </div>

src/app/pages/expenses/expense-page.component.scss

@@ -1,4 +1,4 @@
-.expenses-container {
+.expenses-page-container {
   display: flex;
   flex-direction: column;
   gap: 1rem;

src/app/pages/expenses/expense-page.component.ts

@@ -3,7 +3,7 @@ import { ExpenseListComponent } from '../../components/expense-list/expense-list
 import { ExpenseComponent } from '../../components/expense/expense.component';
 
 @Component({
-  selector: 'app-expenses',
+  selector: 'app-expenses-page',
   imports: [
     ExpenseListComponent,
     ExpenseComponent

src/app/pages/home/home-page.component.html

@@ -1,7 +1,3 @@
-<div class="home-container">
-  <ul>
-    <li>
-      <a routerLink="expenses">ExpenseService</a>
-    </li>
-  </ul>
+<div class="home-page-container">
+  <h2>The common sense expense tracker.</h2>
 </div>

src/app/pages/home/home-page.component.scss

@@ -0,0 +1,7 @@
+h2 {
+  font-size: 1.3rem;
+  line-height: 100%;
+  font-weight: 500;
+  margin: 0;
+  font-family: sans-serif;
+}

src/app/pages/home/home-page.component.ts

@@ -1,12 +1,9 @@
 import { Component } from '@angular/core';
-import { RouterLink } from '@angular/router';
 
 @Component({
-  selector: 'app-home',
-  imports: [
-    RouterLink
-  ],
+  selector: 'app-home-page',
+  imports: [],
   templateUrl: './home-page.component.html',
-  styleUrl: './home-page.component.scss',
+  styleUrl: './home-page.component.scss'
 })
 export class HomePage { }

src/app/pages/metadata/metadata-page.component.html

@@ -0,0 +1,3 @@
+<div class="metadata-page-container">
+  <app-metadata />
+</div>

src/app/pages/metadata/metadata-page.component.ts

@@ -0,0 +1,12 @@
+import { Component } from '@angular/core';
+import { MetadataComponent } from '../../components/metadata/metadata.component';
+
+@Component({
+  selector: 'app-metadata-page',
+  imports: [
+    MetadataComponent
+  ],
+  templateUrl: './metadata-page.component.html',
+  styleUrl: './metadata-page.component.scss'
+})
+export class MetadataPageComponent { }

src/app/pages/reports/reports-page.component.html

@@ -0,0 +1,3 @@
+<div class="reports-page-container">
+  Reports page
+</div>

src/app/pages/reports/reports-page.component.ts

@@ -0,0 +1,9 @@
+import { Component } from '@angular/core';
+
+@Component({
+  selector: 'app-reports-page',
+  imports: [],
+  templateUrl: './reports-page.component.html',
+  styleUrl: './reports-page.component.scss'
+})
+export class ReportsPageComponent { }

src/app/services/category.service.ts

@@ -10,15 +10,27 @@ export class CategoryService {
   public readonly categoryPath = 'http://localhost:3000/common-cents/categories';
 
   public constructor(private readonly http: HttpService) {
-    void this.fetchCategories();
+    void this.fetch();
   }
 
-  public async fetchCategories(): Promise<void> {
+  public async fetch(): Promise<void> {
     this.internalCategories.set(await this.http.get<Category[]>(this.categoryPath));
   }
+
+  public async create(category: CreateCategory): Promise<Category> {
+    return await this.http.post<Category>(this.categoryPath, category);
+  }
+
+  public async update(category: Category): Promise<Category> {
+    return await this.http.put<Category>(this.categoryPath, category);
+  }
 }
 
 export interface Category {
   id: string;
   name: string;
 }
+
+export interface CreateCategory {
+  name: string;
+}

src/app/services/expense.service.ts

@@ -14,21 +14,18 @@ export class ExpenseService {
   public readonly expensePath = 'http://localhost:3000/common-cents/expenses'; // TODO: refactor
 
   public constructor(private readonly http: HttpService) {
-    void this.fetchExpenses();
+    void this.fetch();
   }
 
-  public async fetchExpenses(): Promise<void> {
+  public async fetch(): Promise<void> {
     this.internalExpenses.set(await this.http.get(this.expensePath));
   }
 
-  public async postExpense(createExpense: CreateExpense): Promise<Expense> {
-    const createdExpense = await this.http.post<Expense>(this.expensePath, createExpense);
-    await this.fetchExpenses();
-
-    return createdExpense;
+  public async create(createExpense: CreateExpense): Promise<Expense> {
+    return await this.http.post<Expense>(this.expensePath, createExpense);
   }
 
-  public async updateExpense(updateExpense: UpdateExpense): Promise<Expense> {
+  public async update(updateExpense: UpdateExpense): Promise<Expense> {
     return await this.http.put<Expense>(this.expensePath, updateExpense);
   }
 }
@@ -38,18 +35,18 @@ export interface Expense {
   date: Date;
   cents: number;
   category: Category;
-  note?: string;
   merchant?: Merchant;
+  note?: string;
   tags: Tag[];
 }
 
 export interface CreateExpense {
   date: Temporal.PlainDate;
   cents: number;
-  categoryId: string;
+  category: Category;
+  merchant?: Merchant;
   note?: string;
-  merchantId?: string;
-  tagIds?: string[];
+  tags: Tag[];
 }
 
 export interface UpdateExpense extends CreateExpense {

src/app/services/merchant.service.ts

@@ -10,15 +10,27 @@ export class MerchantService {
   public readonly merchantPath = 'http://localhost:3000/common-cents/merchants';
 
   public constructor(private readonly http: HttpService) {
-    void this.fetchMerchants();
+    void this.fetch();
   }
 
-  public async fetchMerchants(): Promise<void> {
+  public async fetch(): Promise<void> {
     this.internalMerchants.set(await this.http.get<Merchant[]>(this.merchantPath));
   }
+
+  public async create(merchant: CreateMerchant): Promise<Merchant> {
+    return await this.http.post<Merchant>(this.merchantPath, merchant);
+  }
+
+  public async update(merchant: Merchant): Promise<Merchant> {
+    return await this.http.put<Merchant>(this.merchantPath, merchant);
+  }
 }
 
 export interface Merchant {
   id: string;
   name: string;
 }
+
+export interface CreateMerchant {
+  name: string;
+}

src/app/services/tag.service.ts

@@ -10,15 +10,27 @@ export class TagService {
   public readonly tagPath = 'http://localhost:3000/common-cents/tags';
 
   public constructor(private readonly http: HttpService) {
-    void this.fetchTags();
+    void this.fetch();
   }
 
-  public async fetchTags(): Promise<void> {
+  public async fetch(): Promise<void> {
     this.internalTags.set(await this.http.get<Tag[]>(this.tagPath));
   }
+
+  public async create(tag: CreateTag): Promise<Tag> {
+    return await this.http.post<Tag>(this.tagPath, tag);
+  }
+
+  public async update(tag: Tag): Promise<Tag> {
+    return await this.http.put<Tag>(this.tagPath, tag);
+  }
 }
 
 export interface Tag {
   id: string;
   name: string;
 }
+
+export interface CreateTag {
+  name: string;
+}

src/assets/styles/variables.scss

@@ -0,0 +1,2 @@
+$mid-screen: 500px;
+$wide-screen: 800px;

src/index.html

@@ -13,7 +13,7 @@
   <link rel="preconnect" href="https://fonts.googleapis.com">
   <link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
   <link href="https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500&display=swap" rel="stylesheet">
-  <link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
+  <link href="https://fonts.googleapis.com/icon?family=Material+Icons|Material+Icons+Outlined" rel="stylesheet">
 </head>
 <body>
   <app-root></app-root>

src/styles.scss

@@ -10,7 +10,7 @@ html {
   height: 100%;
   @include mat.theme((
     color: (
-      primary: mat.$cyan-palette,
+      primary: mat.$azure-palette,
       tertiary: mat.$orange-palette,
     ),
     typography: Roboto,