Revert "Move behavior from component into view model for change-list-view"

This reverts commit c8a096deb789a0cabb41a7d8a40ce47823988b28.

Reason for revert: Files are not shown on change page when not logged in.

Change-Id: I9c5dafe4e76e0d34c0233b2a76c29d6645937dc3

17 files changed, 306 insertions, 371 deletions

diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view.ts b/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view.ts
index 6b74921ccb..a58c7bb14d 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view.ts
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view.ts
@@ -7,6 +7,7 @@ import '../gr-change-list/gr-change-list';
 import '../gr-repo-header/gr-repo-header';
 import '../gr-user-header/gr-user-header';
 import {page} from '../../../utils/page-wrapper-utils';
+import {navigationToken} from '../../core/gr-navigation/gr-navigation';
 import {
   AccountDetailInfo,
   AccountId,
@@ -25,9 +26,20 @@ import {ValueChangedEvent} from '../../../types/events';
 import {
   createSearchUrl,
   searchViewModelToken,
+  SearchViewState,
 } from '../../../models/views/search';
 import {resolve} from '../../../models/dependency';
 import {subscribe} from '../../lit/subscription-controller';
+import {createChangeUrl} from '../../../models/views/change';
+import {debounce, DelayedTask} from '../../../utils/async-util';
+
+const GET_CHANGES_DEBOUNCE_INTERVAL_MS = 10;
+
+const LOOKUP_QUERY_PATTERNS: RegExp[] = [
+  /^\s*i?[0-9a-f]{7,40}\s*$/i, // CHANGE_ID
+  /^\s*[1-9][0-9]*\s*$/g, // CHANGE_NUM
+  /[0-9a-f]{40}/, // COMMIT
+];
 
 const USER_QUERY_PATTERN = /^owner:\s?("[^"]+"|[^ ]+)$/;
 
@@ -48,6 +60,21 @@ export class GrChangeListView extends LitElement {
 
   @query('#nextArrow') protected nextArrow?: HTMLAnchorElement;
 
+  private _viewState?: SearchViewState;
+
+  @state()
+  get viewState() {
+    return this._viewState;
+  }
+
+  set viewState(viewState: SearchViewState | undefined) {
+    if (this._viewState === viewState) return;
+    const oldViewState = this._viewState;
+    this._viewState = viewState;
+    this.viewStateChanged();
+    this.requestUpdate('viewState', oldViewState);
+  }
+
   // private but used in test
   @state() account?: AccountDetailInfo;
 
@@ -64,19 +91,19 @@ export class GrChangeListView extends LitElement {
   @state() query = '';
 
   // private but used in test
-  @state() offset = 0;
+  @state() offset?: number;
 
   // private but used in test
-  @state() changes: ChangeInfo[] = [];
+  @state() changes?: ChangeInfo[];
 
   // private but used in test
   @state() loading = true;
 
   // private but used in test
-  @state() userId?: AccountId | EmailAddress;
+  @state() userId: AccountId | EmailAddress | null = null;
 
   // private but used in test
-  @state() repo?: RepoName;
+  @state() repo: RepoName | null = null;
 
   @state() selectedIndex = 0;
 
@@ -88,30 +115,17 @@ export class GrChangeListView extends LitElement {
 
   private readonly getViewModel = resolve(this, searchViewModelToken);
 
+  private readonly getNavigation = resolve(this, navigationToken);
+
   constructor() {
     super();
     this.addEventListener('next-page', () => this.handleNextPage());
     this.addEventListener('previous-page', () => this.handlePreviousPage());
-
-    subscribe(
-      this,
-      () => this.getViewModel().query$,
-      x => (this.query = x)
-    );
-    subscribe(
-      this,
-      () => this.getViewModel().offsetNumber$,
-      x => (this.offset = x)
-    );
+    this.addEventListener('reload', () => this.reload());
     subscribe(
       this,
-      () => this.getViewModel().loading$,
-      x => (this.loading = x)
-    );
-    subscribe(
-      this,
-      () => this.getViewModel().changes$,
-      x => (this.changes = x)
+      () => this.getViewModel().state$,
+      x => (this.viewState = x)
     );
     subscribe(
       this,
@@ -125,16 +139,22 @@ export class GrChangeListView extends LitElement {
     );
     subscribe(
       this,
-      () => this.userModel.preferenceChangesPerPage$,
-      x => (this.changesPerPage = x)
-    );
-    subscribe(
-      this,
       () => this.userModel.preferences$,
-      x => (this.preferences = x)
+      x => {
+        this.preferences = x;
+        if (this.changesPerPage !== x.changes_per_page) {
+          this.changesPerPage = x.changes_per_page;
+          this.debouncedGetChanges();
+        }
+      }
     );
   }
 
+  override disconnectedCallback() {
+    this.getChangesTask?.flush();
+    super.disconnectedCallback();
+  }
+
   static override get styles() {
     return [
       sharedStyles,
@@ -262,10 +282,63 @@ export class GrChangeListView extends LitElement {
     }
   }
 
-  override updated(changedProperties: PropertyValues) {
-    if (changedProperties.has('query')) {
-      fireTitleChange(this, this.query);
+  reload() {
+    if (!this.loading) this.debouncedGetChanges();
+  }
+
+  // private, but visible for testing
+  viewStateChanged() {
+    if (!this.viewState) return;
+
+    let offset = Number(this.viewState.offset);
+    if (isNaN(offset)) offset = 0;
+    const query = this.viewState.query ?? '';
+
+    if (this.query !== query) this.selectedIndex = 0;
+    this.loading = true;
+    this.query = query;
+    this.offset = offset;
+
+    // NOTE: This method may be called before attachment. Fire title-change
+    // in an async so that attachment to the DOM can take place first.
+    setTimeout(() => fireTitleChange(this, this.query));
+
+    this.debouncedGetChanges(true);
+  }
+
+  private getChangesTask?: DelayedTask;
+
+  private debouncedGetChanges(shouldSingleMatchRedirect = false) {
+    this.getChangesTask = debounce(
+      this.getChangesTask,
+      () => {
+        this.getChanges(shouldSingleMatchRedirect);
+      },
+      GET_CHANGES_DEBOUNCE_INTERVAL_MS
+    );
+  }
+
+  async getChanges(shouldSingleMatchRedirect = false) {
+    this.loading = true;
+    const changes =
+      (await this.restApiService.getChanges(
+        this.changesPerPage,
+        this.query,
+        this.offset
+      )) ?? [];
+    if (shouldSingleMatchRedirect && this.query && changes.length === 1) {
+      for (const queryPattern of LOOKUP_QUERY_PATTERNS) {
+        if (this.query.match(queryPattern)) {
+          // "Back"/"Forward" buttons work correctly only with replaceUrl()
+          this.getNavigation().replaceUrl(
+            createChangeUrl({change: changes[0]})
+          );
+          return;
+        }
+      }
     }
+    this.changes = changes;
+    this.loading = false;
   }
 
   // private but used in test
@@ -299,12 +372,14 @@ export class GrChangeListView extends LitElement {
   }
 
   private changesChanged() {
-    this.selectedIndex = 0;
-    this.userId = undefined;
-    this.repo = undefined;
-    if (this.changes.length === 0) return;
+    this.userId = null;
+    this.repo = null;
+    const changes = this.changes;
+    if (!changes || !changes.length) {
+      return;
+    }
     if (USER_QUERY_PATTERN.test(this.query)) {
-      const owner = this.changes[0].owner;
+      const owner = changes[0].owner;
       const userId = owner._account_id ? owner._account_id : owner.email;
       if (userId) {
         this.userId = userId;
@@ -312,7 +387,7 @@ export class GrChangeListView extends LitElement {
       }
     }
     if (REPO_QUERY_PATTERN.test(this.query)) {
-      this.repo = this.changes[0].project;
+      this.repo = changes[0].project;
     }
   }
 
diff --git a/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view_test.ts b/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view_test.ts
index 4dc3701cb0..b003b66f9d 100644
--- a/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view_test.ts
+++ b/polygerrit-ui/app/elements/change-list/gr-change-list-view/gr-change-list-view_test.ts
@@ -7,20 +7,45 @@ import '../../../test/common-test-setup';
 import './gr-change-list-view';
 import {GrChangeListView} from './gr-change-list-view';
 import {page} from '../../../utils/page-wrapper-utils';
-import {query, queryAndAssert} from '../../../test/test-utils';
+import {navigationToken} from '../../core/gr-navigation/gr-navigation';
+import {
+  query,
+  stubRestApi,
+  queryAndAssert,
+  stubFlags,
+} from '../../../test/test-utils';
 import {createChange} from '../../../test/test-data-generators';
-import {ChangeInfo, EmailAddress, RepoName} from '../../../api/rest-api';
+import {
+  ChangeInfo,
+  EmailAddress,
+  NumericChangeId,
+  RepoName,
+} from '../../../api/rest-api';
 import {fixture, html, waitUntil, assert} from '@open-wc/testing';
+import {GerritView} from '../../../services/router/router-model';
+import {testResolver} from '../../../test/common-test-setup';
+import {SinonFakeTimers, SinonStub} from 'sinon';
 import {GrChangeList} from '../gr-change-list/gr-change-list';
 import {GrChangeListSection} from '../gr-change-list-section/gr-change-list-section';
 import {GrChangeListItem} from '../gr-change-list-item/gr-change-list-item';
 
+const CHANGE_ID = 'IcA3dAB3edAB9f60B8dcdA6ef71A75980e4B7127';
+const COMMIT_HASH = '12345678';
+
 suite('gr-change-list-view tests', () => {
   let element: GrChangeListView;
+  let changes: ChangeInfo[] | undefined = [];
+  let clock: SinonFakeTimers;
 
   setup(async () => {
+    clock = sinon.useFakeTimers();
+    stubRestApi('getChanges').callsFake(() => Promise.resolve(changes));
     element = await fixture(html`<gr-change-list-view></gr-change-list-view>`);
-    element.query = 'test-query';
+    element.viewState = {
+      view: GerritView.SEARCH,
+      query: 'test-query',
+      offset: '0',
+    };
     await element.updateComplete;
   });
 
@@ -50,9 +75,11 @@ suite('gr-change-list-view tests', () => {
 
   suite('bulk actions', () => {
     setup(async () => {
+      stubFlags('isEnabled').returns(true);
+      changes = [createChange()];
       element.loading = false;
-      element.changes = [createChange()];
-      await element.updateComplete;
+      element.reload();
+      clock.tick(100);
       await element.updateComplete;
       await waitUntil(() => element.loading === false);
     });
@@ -80,9 +107,8 @@ suite('gr-change-list-view tests', () => {
       checkbox.click();
       await waitUntil(() => checkbox.checked);
 
-      element.changes = [createChange()];
+      element.reload();
       await element.updateComplete;
-
       checkbox = queryAndAssert<HTMLInputElement>(
         query(
           query(query(element, 'gr-change-list'), 'gr-change-list-section'),
@@ -196,7 +222,7 @@ suite('gr-change-list-view tests', () => {
   });
 
   test('userId query', async () => {
-    assert.isUndefined(element.userId);
+    assert.isNull(element.userId);
     element.query = 'owner: foo@bar';
     element.changes = [
       {...createChange(), owner: {email: 'foo@bar' as EmailAddress}},
@@ -209,19 +235,19 @@ suite('gr-change-list-view tests', () => {
       {...createChange(), owner: {email: 'foo@bar' as EmailAddress}},
     ];
     await element.updateComplete;
-    assert.isUndefined(element.userId);
+    assert.isNull(element.userId);
   });
 
   test('userId query without email', async () => {
-    assert.isUndefined(element.userId);
+    assert.isNull(element.userId);
     element.query = 'owner: foo@bar';
     element.changes = [{...createChange(), owner: {}}];
     await element.updateComplete;
-    assert.isUndefined(element.userId);
+    assert.isNull(element.userId);
   });
 
   test('repo query', async () => {
-    assert.isUndefined(element.repo);
+    assert.isNull(element.repo);
     element.query = 'project: test-repo';
     element.changes = [
       {
@@ -238,11 +264,11 @@ suite('gr-change-list-view tests', () => {
       {...createChange(), owner: {email: 'foo@bar' as EmailAddress}},
     ];
     await element.updateComplete;
-    assert.isUndefined(element.repo);
+    assert.isNull(element.repo);
   });
 
   test('repo query with open status', async () => {
-    assert.isUndefined(element.repo);
+    assert.isNull(element.repo);
     element.query = 'project:test-repo status:open';
     element.changes = [
       {
@@ -259,6 +285,74 @@ suite('gr-change-list-view tests', () => {
       {...createChange(), owner: {email: 'foo@bar' as EmailAddress}},
     ];
     await element.updateComplete;
-    assert.isUndefined(element.repo);
+    assert.isNull(element.repo);
+  });
+
+  suite('query based navigation', () => {
+    let replaceUrlStub: SinonStub;
+    setup(() => {
+      replaceUrlStub = sinon.stub(testResolver(navigationToken), 'replaceUrl');
+    });
+
+    teardown(async () => {
+      await element.updateComplete;
+      sinon.restore();
+    });
+
+    test('Searching for a change ID redirects to change', async () => {
+      const change = {...createChange(), _number: 1 as NumericChangeId};
+      changes = [change];
+
+      element.viewState = {view: GerritView.SEARCH, query: CHANGE_ID};
+      clock.tick(100);
+      await element.updateComplete;
+
+      assert.isTrue(replaceUrlStub.called);
+      assert.equal(replaceUrlStub.lastCall.firstArg, '/c/test-project/+/1');
+    });
+
+    test('Searching for a change num redirects to change', async () => {
+      const change = {...createChange(), _number: 1 as NumericChangeId};
+      changes = [change];
+
+      element.viewState = {view: GerritView.SEARCH, query: '1'};
+      clock.tick(100);
+      await element.updateComplete;
+
+      assert.isTrue(replaceUrlStub.called);
+      assert.equal(replaceUrlStub.lastCall.firstArg, '/c/test-project/+/1');
+    });
+
+    test('Commit hash redirects to change', async () => {
+      const change = {...createChange(), _number: 1 as NumericChangeId};
+      changes = [change];
+
+      element.viewState = {view: GerritView.SEARCH, query: COMMIT_HASH};
+      clock.tick(100);
+      await element.updateComplete;
+
+      assert.isTrue(replaceUrlStub.called);
+      assert.equal(replaceUrlStub.lastCall.firstArg, '/c/test-project/+/1');
+    });
+
+    test('Searching for an invalid change ID searches', async () => {
+      changes = [];
+
+      element.viewState = {view: GerritView.SEARCH, query: CHANGE_ID};
+      clock.tick(100);
+      await element.updateComplete;
+
+      assert.isFalse(replaceUrlStub.called);
+    });
+
+    test('Change ID with multiple search results searches', async () => {
+      changes = undefined;
+
+      element.viewState = {view: GerritView.SEARCH, query: CHANGE_ID};
+      clock.tick(100);
+      await element.updateComplete;
+
+      assert.isFalse(replaceUrlStub.called);
+    });
   });
 });
diff --git a/polygerrit-ui/app/elements/core/gr-router/gr-router.ts b/polygerrit-ui/app/elements/core/gr-router/gr-router.ts
index e40a1619a1..762f6b70ce 100644
--- a/polygerrit-ui/app/elements/core/gr-router/gr-router.ts
+++ b/polygerrit-ui/app/elements/core/gr-router/gr-router.ts
@@ -1292,8 +1292,6 @@ export class GrRouter implements Finalizable, NavigationService {
       view: GerritView.SEARCH,
       query: ctx.params[0],
       offset: ctx.params[2],
-      changes: [],
-      loading: false,
     };
     this.setState(state);
     this.searchViewModel.setState(state);
@@ -1306,8 +1304,6 @@ export class GrRouter implements Finalizable, NavigationService {
     const state: SearchViewState = {
       view: GerritView.SEARCH,
       query: ctx.params[0],
-      changes: [],
-      loading: false,
     };
     this.setState(state);
     this.searchViewModel.setState(state);
diff --git a/polygerrit-ui/app/elements/core/gr-router/gr-router_test.ts b/polygerrit-ui/app/elements/core/gr-router/gr-router_test.ts
index 6c29336476..ce3ed0d68b 100644
--- a/polygerrit-ui/app/elements/core/gr-router/gr-router_test.ts
+++ b/polygerrit-ui/app/elements/core/gr-router/gr-router_test.ts
@@ -403,8 +403,6 @@ suite('gr-router tests', () => {
         view: GerritView.SEARCH,
         query: 'project:foo/bar/baz',
         offset: undefined,
-        changes: [],
-        loading: false,
       });
 
       ctx.params[1] = '123';
@@ -413,8 +411,6 @@ suite('gr-router tests', () => {
         view: GerritView.SEARCH,
         query: 'project:foo/bar/baz',
         offset: '123',
-        changes: [],
-        loading: false,
       });
     });
 
@@ -433,8 +429,6 @@ suite('gr-router tests', () => {
       assertctxToParams(ctx, 'handleChangeIdQueryRoute', {
         view: GerritView.SEARCH,
         query: 'I0123456789abcdef0123456789abcdef01234567',
-        changes: [],
-        loading: false,
       });
     });
 
diff --git a/polygerrit-ui/app/models/change/change-model.ts b/polygerrit-ui/app/models/change/change-model.ts
index b4f16abcc8..5cfe670fbc 100644
--- a/polygerrit-ui/app/models/change/change-model.ts
+++ b/polygerrit-ui/app/models/change/change-model.ts
@@ -14,7 +14,15 @@ import {
   RevisionPatchSetNum,
 } from '../../types/common';
 import {DefaultBase} from '../../constants/constants';
-import {combineLatest, from, fromEvent, Observable, forkJoin, of} from 'rxjs';
+import {
+  combineLatest,
+  from,
+  fromEvent,
+  Observable,
+  Subscription,
+  forkJoin,
+  of,
+} from 'rxjs';
 import {
   map,
   filter,
@@ -253,6 +261,8 @@ export class ChangeModel extends Model<ChangeState> implements Finalizable {
     ([change, account]) => isOwner(change, account)
   );
 
+  private subscriptions: Subscription[] = [];
+
   // For usage in `combineLatest` we need `startWith` such that reload$ has an
   // initial value.
   readonly reload$: Observable<unknown> = fromEvent(document, 'reload').pipe(
@@ -306,6 +316,13 @@ export class ChangeModel extends Model<ChangeState> implements Finalizable {
     ];
   }
 
+  override finalize() {
+    for (const s of this.subscriptions) {
+      s.unsubscribe();
+    }
+    this.subscriptions = [];
+  }
+
   // Temporary workaround until path is derived in the model itself.
   updatePath(diffPath?: string) {
     this.updateState({diffPath});
diff --git a/polygerrit-ui/app/models/change/files-model.ts b/polygerrit-ui/app/models/change/files-model.ts
index 6922f6dce5..31e42a6090 100644
--- a/polygerrit-ui/app/models/change/files-model.ts
+++ b/polygerrit-ui/app/models/change/files-model.ts
@@ -12,7 +12,7 @@ import {
   PatchSetNumber,
   RevisionPatchSetNum,
 } from '../../types/common';
-import {combineLatest, of, from} from 'rxjs';
+import {combineLatest, Subscription, of, from} from 'rxjs';
 import {switchMap, map} from 'rxjs/operators';
 import {RestApiService} from '../../services/gr-rest-api/gr-rest-api';
 import {Finalizable} from '../../services/registry';
@@ -131,6 +131,8 @@ export class FilesModel extends Model<FilesState> implements Finalizable {
     state => state.filesRightBase
   );
 
+  private subscriptions: Subscription[] = [];
+
   constructor(
     readonly changeModel: ChangeModel,
     readonly commentsModel: CommentsModel,
@@ -196,4 +198,11 @@ export class FilesModel extends Model<FilesState> implements Finalizable {
         this.updateState(state);
       });
   }
+
+  override finalize() {
+    for (const s of this.subscriptions) {
+      s.unsubscribe();
+    }
+    this.subscriptions = [];
+  }
 }
diff --git a/polygerrit-ui/app/models/checks/checks-model.ts b/polygerrit-ui/app/models/checks/checks-model.ts
index 61c2f77ad7..bb46f278de 100644
--- a/polygerrit-ui/app/models/checks/checks-model.ts
+++ b/polygerrit-ui/app/models/checks/checks-model.ts
@@ -20,6 +20,7 @@ import {
   Observable,
   of,
   Subject,
+  Subscription,
   timer,
 } from 'rxjs';
 import {
@@ -207,6 +208,8 @@ export class ChecksModel extends Model<ChecksState> implements Finalizable {
 
   private readonly visibilityChangeListener: () => void;
 
+  private subscriptions: Subscription[] = [];
+
   public checksSelectedPatchsetNumber$ = select(
     this.state$,
     state => state.patchsetNumberSelected
@@ -480,7 +483,10 @@ export class ChecksModel extends Model<ChecksState> implements Finalizable {
       'visibilitychange',
       this.visibilityChangeListener
     );
-    super.finalize();
+    for (const s of this.subscriptions) {
+      s.unsubscribe();
+    }
+    this.subscriptions = [];
   }
 
   // Must only be used by the checks service or whatever is in control of this
diff --git a/polygerrit-ui/app/models/comments/comments-model.ts b/polygerrit-ui/app/models/comments/comments-model.ts
index 8ed4b69cc7..39d9eaaabf 100644
--- a/polygerrit-ui/app/models/comments/comments-model.ts
+++ b/polygerrit-ui/app/models/comments/comments-model.ts
@@ -30,7 +30,7 @@ import {select} from '../../utils/observable-util';
 import {RouterModel} from '../../services/router/router-model';
 import {Finalizable} from '../../services/registry';
 import {define} from '../dependency';
-import {combineLatest, forkJoin, from, Observable} from 'rxjs';
+import {combineLatest, forkJoin, from, Observable, Subscription} from 'rxjs';
 import {fire, fireAlert, fireEvent} from '../../utils/event-util';
 import {CURRENT} from '../../utils/patch-set-util';
 import {RestApiService} from '../../services/gr-rest-api/gr-rest-api';
@@ -370,6 +370,8 @@ export class CommentsModel extends Model<CommentState> implements Finalizable {
 
   private readonly reloadListener: () => void;
 
+  private readonly subscriptions: Subscription[] = [];
+
   private drafts: {[path: string]: DraftInfo[]} = {};
 
   private draftToastTask?: DelayedTask;
@@ -419,7 +421,10 @@ export class CommentsModel extends Model<CommentState> implements Finalizable {
 
   override finalize() {
     document.removeEventListener('reload', this.reloadListener);
-    super.finalize();
+    for (const s of this.subscriptions) {
+      s.unsubscribe();
+    }
+    this.subscriptions.splice(0, this.subscriptions.length);
   }
 
   // Note that this does *not* reload ported comments.
diff --git a/polygerrit-ui/app/models/config/config-model.ts b/polygerrit-ui/app/models/config/config-model.ts
index 6e374d1ca2..c4bd637885 100644
--- a/polygerrit-ui/app/models/config/config-model.ts
+++ b/polygerrit-ui/app/models/config/config-model.ts
@@ -4,7 +4,7 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 import {ConfigInfo, RepoName, ServerInfo} from '../../types/common';
-import {from, of} from 'rxjs';
+import {from, of, Subscription} from 'rxjs';
 import {switchMap} from 'rxjs/operators';
 import {Finalizable} from '../../services/registry';
 import {RestApiService} from '../../services/gr-rest-api/gr-rest-api';
@@ -50,6 +50,8 @@ export class ConfigModel extends Model<ConfigState> implements Finalizable {
     url => url
   );
 
+  private subscriptions: Subscription[];
+
   constructor(
     readonly changeModel: ChangeModel,
     readonly restApiService: RestApiService
@@ -81,4 +83,11 @@ export class ConfigModel extends Model<ConfigState> implements Finalizable {
   updateServerConfig(serverConfig?: ServerInfo) {
     this.updateState({serverConfig});
   }
+
+  override finalize() {
+    for (const s of this.subscriptions) {
+      s.unsubscribe();
+    }
+    this.subscriptions = [];
+  }
 }
diff --git a/polygerrit-ui/app/models/model.ts b/polygerrit-ui/app/models/model.ts
index c44c0bf4f8..7cd8b2a9a5 100644
--- a/polygerrit-ui/app/models/model.ts
+++ b/polygerrit-ui/app/models/model.ts
@@ -3,7 +3,7 @@
  * Copyright 2021 Google LLC
  * SPDX-License-Identifier: Apache-2.0
  */
-import {BehaviorSubject, Observable, Subscription} from 'rxjs';
+import {BehaviorSubject, Observable} from 'rxjs';
 import {Finalizable} from '../services/registry';
 
 /**
@@ -25,8 +25,6 @@ export abstract class Model<T> implements Finalizable {
 
   public state$: Observable<T>;
 
-  protected subscriptions: Subscription[] = [];
-
   constructor(initialState: T) {
     this.subject$ = new BehaviorSubject(initialState);
     this.state$ = this.subject$.asObservable();
@@ -46,9 +44,5 @@ export abstract class Model<T> implements Finalizable {
 
   finalize() {
     this.subject$.complete();
-    for (const s of this.subscriptions) {
-      s.unsubscribe();
-    }
-    this.subscriptions = [];
   }
 }
diff --git a/polygerrit-ui/app/models/user/user-model.ts b/polygerrit-ui/app/models/user/user-model.ts
index bb607e9271..b69c7150e7 100644
--- a/polygerrit-ui/app/models/user/user-model.ts
+++ b/polygerrit-ui/app/models/user/user-model.ts
@@ -3,8 +3,8 @@
  * Copyright 2021 Google LLC
  * SPDX-License-Identifier: Apache-2.0
  */
-import {from, of, Observable} from 'rxjs';
-import {filter, switchMap} from 'rxjs/operators';
+import {from, of, Observable, Subscription} from 'rxjs';
+import {switchMap} from 'rxjs/operators';
 import {
   DiffPreferencesInfo as DiffPreferencesInfoAPI,
   DiffViewMode,
@@ -26,62 +26,24 @@ import {DiffPreferencesInfo} from '../../types/diff';
 import {Finalizable} from '../../services/registry';
 import {select} from '../../utils/observable-util';
 import {Model} from '../model';
-import {isDefined} from '../../utils/common-util';
 
 export interface UserState {
   /**
    * Keeps being defined even when credentials have expired.
-   *
-   * `undefined` can mean that the app is still starting up and we have not
-   * tried loading an account object yet. If you want to wait until the
-   * `account` is known, then use `accountLoaded` below.
    */
   account?: AccountDetailInfo;
-  /**
-   * Starts as `false` and switches to `true` after the first `getAccount` call.
-   * A common use case for this is to wait with loading or doing something until
-   * we know whether the user is logged in or not, see `loadedAccount$` below.
-   *
-   * This value cannot change back to `false` once it has become `true`.
-   *
-   * This value does *not* indicate whether the user is logged in or whether an
-   * `account` object is available. If the first `getAccount()` call returns
-   * `undefined`, then `accountLoaded` still becomes true, even if `account`
-   * stays `undefined`.
-   */
-  accountLoaded: boolean;
-  preferences?: PreferencesInfo;
-  diffPreferences?: DiffPreferencesInfo;
-  editPreferences?: EditPreferencesInfo;
+  preferences: PreferencesInfo;
+  diffPreferences: DiffPreferencesInfo;
+  editPreferences: EditPreferencesInfo;
   capabilities?: AccountCapabilityInfo;
 }
 
 export class UserModel extends Model<UserState> implements Finalizable {
-  /**
-   * Note that the initially emitted `undefined` value can mean "not loaded
-   * the account into object yet" or "user is not logged in". Consider using
-   * `loadedAccount$` below.
-   *
-   * TODO: Maybe consider changing all usages to `loadedAccount$`.
-   */
   readonly account$: Observable<AccountDetailInfo | undefined> = select(
     this.state$,
     userState => userState.account
   );
 
-  /**
-   * Only emits once we have tried to actually load the account. Note that
-   * this does not initially emit a value.
-   *
-   * So if this emits `undefined`, then you actually know that the user is not
-   * logged in. And for logged in users you will never get an initial
-   * `undefined` emission.
-   */
-  readonly loadedAccount$: Observable<AccountDetailInfo | undefined> = select(
-    this.state$.pipe(filter(s => s.accountLoaded)),
-    userState => userState.account
-  );
-
   /** Note that this may still be true, even if credentials have expired. */
   readonly loggedIn$: Observable<boolean> = select(
     this.account$,
@@ -99,17 +61,17 @@ export class UserModel extends Model<UserState> implements Finalizable {
   readonly preferences$: Observable<PreferencesInfo> = select(
     this.state$,
     userState => userState.preferences
-  ).pipe(filter(isDefined));
+  );
 
   readonly diffPreferences$: Observable<DiffPreferencesInfo> = select(
     this.state$,
     userState => userState.diffPreferences
-  ).pipe(filter(isDefined));
+  );
 
   readonly editPreferences$: Observable<EditPreferencesInfo> = select(
     this.state$,
     userState => userState.editPreferences
-  ).pipe(filter(isDefined));
+  );
 
   readonly preferenceDiffViewMode$: Observable<DiffViewMode> = select(
     this.preferences$,
@@ -121,14 +83,13 @@ export class UserModel extends Model<UserState> implements Finalizable {
     preference => preference.theme
   );
 
-  readonly preferenceChangesPerPage$: Observable<number> = select(
-    this.preferences$,
-    preference => preference.changes_per_page
-  );
+  private subscriptions: Subscription[] = [];
 
   constructor(readonly restApiService: RestApiService) {
     super({
-      accountLoaded: false,
+      preferences: createDefaultPreferences(),
+      diffPreferences: createDefaultDiffPrefs(),
+      editPreferences: createDefaultEditPrefs(),
     });
     this.subscriptions = [
       from(this.restApiService.getAccount()).subscribe(
@@ -136,7 +97,7 @@ export class UserModel extends Model<UserState> implements Finalizable {
           this.setAccount(account);
         }
       ),
-      this.loadedAccount$
+      this.account$
         .pipe(
           switchMap(account => {
             if (!account) return of(createDefaultPreferences());
@@ -146,7 +107,7 @@ export class UserModel extends Model<UserState> implements Finalizable {
         .subscribe((preferences?: PreferencesInfo) => {
           this.setPreferences(preferences ?? createDefaultPreferences());
         }),
-      this.loadedAccount$
+      this.account$
         .pipe(
           switchMap(account => {
             if (!account) return of(createDefaultDiffPrefs());
@@ -156,7 +117,7 @@ export class UserModel extends Model<UserState> implements Finalizable {
         .subscribe((diffPrefs?: DiffPreferencesInfoAPI) => {
           this.setDiffPreferences(diffPrefs ?? createDefaultDiffPrefs());
         }),
-      this.loadedAccount$
+      this.account$
         .pipe(
           switchMap(account => {
             if (!account) return of(createDefaultEditPrefs());
@@ -166,7 +127,7 @@ export class UserModel extends Model<UserState> implements Finalizable {
         .subscribe((editPrefs?: EditPreferencesInfo) => {
           this.setEditPreferences(editPrefs ?? createDefaultEditPrefs());
         }),
-      this.loadedAccount$
+      this.account$
         .pipe(
           switchMap(account => {
             if (!account) return of(undefined);
@@ -179,6 +140,13 @@ export class UserModel extends Model<UserState> implements Finalizable {
     ];
   }
 
+  override finalize() {
+    for (const s of this.subscriptions) {
+      s.unsubscribe();
+    }
+    this.subscriptions = [];
+  }
+
   updatePreferences(prefs: Partial<PreferencesInfo>) {
     return this.restApiService
       .savePreferences(prefs)
@@ -237,6 +205,6 @@ export class UserModel extends Model<UserState> implements Finalizable {
   }
 
   setAccount(account?: AccountDetailInfo) {
-    this.updateState({account, accountLoaded: true});
+    this.updateState({account});
   }
 }
diff --git a/polygerrit-ui/app/models/views/search.ts b/polygerrit-ui/app/models/views/search.ts
index d601488287..58cb8f7ab5 100644
--- a/polygerrit-ui/app/models/views/search.ts
+++ b/polygerrit-ui/app/models/views/search.ts
@@ -3,61 +3,18 @@
  * Copyright 2022 Google LLC
  * SPDX-License-Identifier: Apache-2.0
  */
-import {combineLatest, fromEvent, Observable} from 'rxjs';
-import {
-  filter,
-  map,
-  startWith,
-  switchMap,
-  tap,
-  withLatestFrom,
-} from 'rxjs/operators';
-import {RepoName, BranchName, TopicName, ChangeInfo} from '../../api/rest-api';
-import {NavigationService} from '../../elements/core/gr-navigation/gr-navigation';
-import {RestApiService} from '../../services/gr-rest-api/gr-rest-api';
+import {RepoName, BranchName, TopicName} from '../../api/rest-api';
 import {GerritView} from '../../services/router/router-model';
-import {select} from '../../utils/observable-util';
 import {addQuotesWhen} from '../../utils/string-util';
 import {encodeURL} from '../../utils/url-util';
 import {define} from '../dependency';
 import {Model} from '../model';
-import {UserModel} from '../user/user-model';
 import {ViewState} from './base';
-import {createChangeUrl} from './change';
-
-const LOOKUP_QUERY_PATTERNS: RegExp[] = [
-  /^\s*i?[0-9a-f]{7,40}\s*$/i, // CHANGE_ID
-  /^\s*[1-9][0-9]*\s*$/g, // CHANGE_NUM
-  /[0-9a-f]{40}/, // COMMIT
-];
 
 export interface SearchViewState extends ViewState {
   view: GerritView.SEARCH;
-  /**
-   * The query for searching changes.
-   *
-   * Changing this to something non-empty will trigger search.
-   */
-  query: string;
-  /**
-   * How many initial search results should be skipped? This is for showing
-   * more than one search result page. This must be a non-negative number.
-   * If the string is not provided or cannot be parsed as expected, then the
-   * offset falls back to 0.
-   *
-   * TODO: Consider converting from string to number before writing to the
-   * state object.
-   */
+  query?: string;
   offset?: string;
-
-  /**
-   * Is a search API call currrently in progress?
-   */
-  loading: boolean;
-  /**
-   * The search results for the current query.
-   */
-  changes: ChangeInfo[];
 }
 
 export interface SearchUrlOptions {
@@ -129,108 +86,8 @@ export function createSearchUrl(params: SearchUrlOptions): string {
 export const searchViewModelToken =
   define<SearchViewModel>('search-view-model');
 
-/**
- * This is the view model for the search page.
- *
- * It keeps track of the overall search view state and provides selectors for
- * subscribing to certain slices of the state.
- *
- * It manages loading the changes to be shown on the search page by providing
- * `changes` in its state. Changes to the view state or certain user preferences
- * will automatically trigger reloading the changes.
- */
 export class SearchViewModel extends Model<SearchViewState | undefined> {
-  public readonly query$ = select(this.state$, s => s?.query ?? '');
-
-  private readonly offset$ = select(this.state$, s => s?.offset ?? '0');
-
-  /**
-   * Convenience selector for getting the `offset` as a number.
-   *
-   * TODO: Consider changing the type of `offset$` and `state.offset` to
-   * `number`.
-   */
-  public readonly offsetNumber$ = select(this.offset$, offset => {
-    const offsetNumber = Number(offset);
-    return Number.isFinite(offsetNumber) ? offsetNumber : 0;
-  });
-
-  public readonly changes$ = select(this.state$, s => s?.changes ?? []);
-
-  public readonly loading$ = select(this.state$, s => s?.loading ?? false);
-
-  // For usage in `combineLatest` we need `startWith` such that reload$ has an
-  // initial value.
-  private readonly reload$: Observable<unknown> = fromEvent(
-    document,
-    'reload'
-  ).pipe(startWith(undefined));
-
-  private readonly reloadChangesTrigger$ = combineLatest([
-    this.reload$,
-    this.query$,
-    this.offsetNumber$,
-    this.userModel.preferenceChangesPerPage$,
-  ]).pipe(
-    map(([_reload, query, offsetNumber, changesPerPage]) => {
-      const params: [string, number, number] = [
-        query,
-        offsetNumber,
-        changesPerPage,
-      ];
-      return params;
-    })
-  );
-
-  constructor(
-    private readonly restApiService: RestApiService,
-    private readonly userModel: UserModel,
-    private readonly getNavigation: () => NavigationService
-  ) {
+  constructor() {
     super(undefined);
-    this.subscriptions = [
-      this.reloadChangesTrigger$
-        .pipe(
-          switchMap(a => this.reloadChanges(a)),
-          tap(changes => this.updateState({changes, loading: false}))
-        )
-        .subscribe(),
-      this.changes$
-        .pipe(
-          filter(changes => changes.length === 1),
-          withLatestFrom(this.query$)
-        )
-        .subscribe(([changes, query]) =>
-          this.redirectSingleResult(query, changes)
-        ),
-    ];
-  }
-
-  private async reloadChanges([query, offset, changesPerPage]: [
-    string,
-    number,
-    number
-  ]): Promise<ChangeInfo[]> {
-    if (this.getState() === undefined) return [];
-    if (query.trim().length === 0) return [];
-    this.updateState({loading: true});
-    const changes = await this.restApiService.getChanges(
-      changesPerPage,
-      query,
-      offset
-    );
-    return changes ?? [];
-  }
-
-  // visible for testing
-  redirectSingleResult(query: string, changes: ChangeInfo[]): void {
-    if (changes.length !== 1) return;
-    for (const queryPattern of LOOKUP_QUERY_PATTERNS) {
-      if (query.match(queryPattern)) {
-        // "Back"/"Forward" buttons work correctly only with replaceUrl()
-        this.getNavigation().replaceUrl(createChangeUrl({change: changes[0]}));
-        return;
-      }
-    }
   }
 }
diff --git a/polygerrit-ui/app/models/views/search_test.ts b/polygerrit-ui/app/models/views/search_test.ts
index bb2c0e33f5..138ce1ec09 100644
--- a/polygerrit-ui/app/models/views/search_test.ts
+++ b/polygerrit-ui/app/models/views/search_test.ts
@@ -4,26 +4,9 @@
  * SPDX-License-Identifier: Apache-2.0
  */
 import {assert} from '@open-wc/testing';
-import {SinonStub} from 'sinon';
-import {
-  BranchName,
-  NumericChangeId,
-  RepoName,
-  TopicName,
-} from '../../api/rest-api';
-import {navigationToken} from '../../elements/core/gr-navigation/gr-navigation';
+import {BranchName, RepoName, TopicName} from '../../api/rest-api';
 import '../../test/common-test-setup';
-import {testResolver} from '../../test/common-test-setup';
-import {createChange} from '../../test/test-data-generators';
-import {
-  createSearchUrl,
-  SearchUrlOptions,
-  SearchViewModel,
-  searchViewModelToken,
-} from './search';
-
-const CHANGE_ID = 'IcA3dAB3edAB9f60B8dcdA6ef71A75980e4B7127';
-const COMMIT_HASH = '12345678';
+import {createSearchUrl, SearchUrlOptions} from './search';
 
 suite('search view state tests', () => {
   test('createSearchUrl', () => {
@@ -70,60 +53,4 @@ suite('search view state tests', () => {
     options = {topic: 'test:test' as TopicName};
     assert.equal(createSearchUrl(options), '/q/topic:"test:test"');
   });
-
-  suite('query based navigation', () => {
-    let replaceUrlStub: SinonStub;
-    let model: SearchViewModel;
-
-    setup(() => {
-      model = testResolver(searchViewModelToken);
-      replaceUrlStub = sinon.stub(testResolver(navigationToken), 'replaceUrl');
-    });
-
-    teardown(() => {
-      model.finalize();
-    });
-
-    test('Searching for a change ID redirects to change', async () => {
-      const change = {...createChange(), _number: 1 as NumericChangeId};
-
-      model.redirectSingleResult(CHANGE_ID, [change]);
-
-      assert.isTrue(replaceUrlStub.called);
-      assert.equal(replaceUrlStub.lastCall.firstArg, '/c/test-project/+/1');
-    });
-
-    test('Searching for a change num redirects to change', async () => {
-      const change = {...createChange(), _number: 1 as NumericChangeId};
-
-      model.redirectSingleResult('1', [change]);
-
-      assert.isTrue(replaceUrlStub.called);
-      assert.equal(replaceUrlStub.lastCall.firstArg, '/c/test-project/+/1');
-    });
-
-    test('Commit hash redirects to change', async () => {
-      const change = {...createChange(), _number: 1 as NumericChangeId};
-
-      model.redirectSingleResult(COMMIT_HASH, [change]);
-
-      assert.isTrue(replaceUrlStub.called);
-      assert.equal(replaceUrlStub.lastCall.firstArg, '/c/test-project/+/1');
-    });
-
-    test('No results: no redirect', async () => {
-      model.redirectSingleResult(CHANGE_ID, []);
-
-      assert.isFalse(replaceUrlStub.called);
-    });
-
-    test('More than 1 result: no redirect', async () => {
-      const change1 = {...createChange(), _number: 1 as NumericChangeId};
-      const change2 = {...createChange(), _number: 2 as NumericChangeId};
-
-      model.redirectSingleResult(CHANGE_ID, [change1, change2]);
-
-      assert.isFalse(replaceUrlStub.called);
-    });
-  });
 });
diff --git a/polygerrit-ui/app/services/app-context-init.ts b/polygerrit-ui/app/services/app-context-init.ts
index f74cfdffa4..9f7a0c09bf 100644
--- a/polygerrit-ui/app/services/app-context-init.ts
+++ b/polygerrit-ui/app/services/app-context-init.ts
@@ -57,10 +57,7 @@ import {GroupViewModel, groupViewModelToken} from '../models/views/group';
 import {PluginViewModel, pluginViewModelToken} from '../models/views/plugin';
 import {RepoViewModel, repoViewModelToken} from '../models/views/repo';
 import {SearchViewModel, searchViewModelToken} from '../models/views/search';
-import {
-  NavigationService,
-  navigationToken,
-} from '../elements/core/gr-navigation/gr-navigation';
+import {navigationToken} from '../elements/core/gr-navigation/gr-navigation';
 
 /**
  * The AppContext lazy initializator for all services
@@ -134,11 +131,7 @@ export function createAppDependencies(
   dependencies.set(pluginViewModelToken, pluginViewModel);
   const repoViewModel = new RepoViewModel();
   dependencies.set(repoViewModelToken, repoViewModel);
-  const searchViewModel = new SearchViewModel(
-    appContext.restApiService,
-    appContext.userModel,
-    () => dependencies.get(navigationToken) as unknown as NavigationService
-  );
+  const searchViewModel = new SearchViewModel();
   dependencies.set(searchViewModelToken, searchViewModel);
   const settingsViewModel = new SettingsViewModel();
   dependencies.set(settingsViewModelToken, settingsViewModel);
diff --git a/polygerrit-ui/app/test/test-app-context-init.ts b/polygerrit-ui/app/test/test-app-context-init.ts
index eec5446b98..e34773eb38 100644
--- a/polygerrit-ui/app/test/test-app-context-init.ts
+++ b/polygerrit-ui/app/test/test-app-context-init.ts
@@ -138,10 +138,7 @@ export function createTestDependencies(
   dependencies.set(pluginViewModelToken, pluginViewModelCreator);
   const repoViewModelCreator = () => new RepoViewModel();
   dependencies.set(repoViewModelToken, repoViewModelCreator);
-  const searchViewModelCreator = () =>
-    new SearchViewModel(appContext.restApiService, appContext.userModel, () =>
-      resolver(navigationToken)
-    );
+  const searchViewModelCreator = () => new SearchViewModel();
   dependencies.set(searchViewModelToken, searchViewModelCreator);
   const settingsViewModelCreator = () => new SettingsViewModel();
   dependencies.set(settingsViewModelToken, settingsViewModelCreator);
diff --git a/polygerrit-ui/app/test/test-data-generators.ts b/polygerrit-ui/app/test/test-data-generators.ts
index 310fe67569..3579bb370d 100644
--- a/polygerrit-ui/app/test/test-data-generators.ts
+++ b/polygerrit-ui/app/test/test-data-generators.ts
@@ -705,8 +705,6 @@ export function createAppElementSearchViewParams(): SearchViewState {
     view: GerritView.SEARCH,
     query: TEST_NUMERIC_CHANGE_ID.toString(),
     offset: '0',
-    changes: [],
-    loading: false,
   };
 }
 
diff --git a/polygerrit-ui/app/utils/common-util.ts b/polygerrit-ui/app/utils/common-util.ts
index 6c2774eaa9..05c054b8ae 100644
--- a/polygerrit-ui/app/utils/common-util.ts
+++ b/polygerrit-ui/app/utils/common-util.ts
@@ -47,10 +47,6 @@ export function assert(
   if (!condition) throw new Error(errorMessage);
 }
 
-export function isDefined<T>(x: T): x is NonNullable<T> {
-  return x !== undefined && x !== null;
-}
-
 /**
  * Throws an error if the property is not defined.
  */