Handle automatic timezone override

refs https://github.com/TryGhost/Ghost/pull/7142, https://github.com/TryGhost/Ghost/pull/7143
- moves timezone selection template and logic into a component
- detect if the current `activeTimezone` is not in our pre-defined list of timezones, if it isn't:
  - add a line indicating that there has been an override with the current `activeTimezone` value
  - add a blank option to the timezone select list

ghost/admin/app/components/gh-timezone-select.js

@@ -0,0 +1,61 @@
+import Component from 'ember-component';
+import computed, {mapBy} from 'ember-computed';
+import injectService from 'ember-service/inject';
+import {invokeAction} from 'ember-invoke-action';
+
+export default Component.extend({
+    classNames: ['form-group', 'for-select'],
+
+    activeTimezone: null,
+    availableTimezones: null,
+
+    clock: injectService(),
+
+    availableTimezoneNames: mapBy('availableTimezones', 'name'),
+
+    hasTimezoneOverride: computed('activeTimezone', 'availableTimezoneNames', function () {
+        let activeTimezone = this.get('activeTimezone');
+        let availableTimezoneNames = this.get('availableTimezoneNames');
+
+        return !availableTimezoneNames.contains(activeTimezone);
+    }),
+
+    selectedTimezone: computed('activeTimezone', 'availableTimezones', 'hasTimezoneOverride', function () {
+        let hasTimezoneOverride = this.get('hasTimezoneOverride');
+        let activeTimezone = this.get('activeTimezone');
+        let availableTimezones = this.get('availableTimezones');
+
+        if (hasTimezoneOverride) {
+            return {name: '', label: ''};
+        }
+
+        return availableTimezones
+            .filterBy('name', activeTimezone)
+            .get('firstObject');
+    }),
+
+    selectableTimezones: computed('availableTimezones', 'hasTimezoneOverride', function () {
+        let hasTimezoneOverride = this.get('hasTimezoneOverride');
+        let availableTimezones = this.get('availableTimezones');
+
+        if (hasTimezoneOverride) {
+            return [{name: '', label: ''}, ...availableTimezones];
+        }
+
+        return availableTimezones;
+    }),
+
+    localTime: computed('hasTimezoneOverride', 'activeTimezone', 'selectedTimezone', 'clock.second', function () {
+        let hasTimezoneOverride = this.get('hasTimezoneOverride');
+        let timezone = hasTimezoneOverride ? this.get('activeTimezone') : this.get('selectedTimezone.name');
+
+        this.get('clock.second');
+        return timezone ? moment().tz(timezone).format('HH:mm:ss') : moment().utc().format('HH:mm:ss');
+    }),
+
+    actions: {
+        setTimezone(timezone) {
+            invokeAction(this, 'update', timezone);
+        }
+    }
+});

ghost/admin/app/controllers/settings/general.js

@@ -17,7 +17,6 @@ export default Controller.extend(SettingsSaveMixin, {
     config: injectService(),
     _scratchFacebook: null,
     _scratchTwitter: null,
-    clock: injectService(),
 
     selectedTheme: computed('model.activeTheme', 'themes', function () {
         let activeTheme = this.get('model.activeTheme');
@@ -33,15 +32,6 @@ export default Controller.extend(SettingsSaveMixin, {
         return selectedTheme;
     }),
 
-    selectedTimezone: computed('model.activeTimezone', 'availableTimezones', function () {
-        let activeTimezone = this.get('model.activeTimezone');
-        let availableTimezones = this.get('availableTimezones');
-
-        return availableTimezones
-            .filterBy('name', activeTimezone)
-            .get('firstObject');
-    }),
-
     logoImageSource: computed('model.logo', function () {
         return this.get('model.logo') || '';
     }),
@@ -50,12 +40,6 @@ export default Controller.extend(SettingsSaveMixin, {
         return this.get('model.cover') || '';
     }),
 
-    localTime: computed('selectedTimezone', 'clock.second', function () {
-        let timezone = this.get('selectedTimezone.name');
-        this.get('clock.second');
-        return timezone ? moment().tz(timezone).format('HH:mm:ss') : moment().utc().format('HH:mm:ss');
-    }),
-
     isDatedPermalinks: computed('model.permalinks', {
         set(key, value) {
             this.set('model.permalinks', value ? '/:year/:month/:day/:slug/' : '/:slug/');

ghost/admin/app/templates/components/gh-timezone-select.hbs

@@ -0,0 +1,16 @@
+<label for="activeTimezone">Timezone</label>
+<span class="gh-select" data-select-text="{{selectedTimezone.label}}" tabindex="0">
+    {{gh-select-native
+        id="activeTimezone"
+        name="general[activeTimezone]"
+        content=selectableTimezones
+        optionValuePath="name"
+        optionLabelPath="label"
+        selection=selectedTimezone
+        action="setTimezone"
+    }}
+</span>
+{{#if hasTimezoneOverride}}
+    <p>Your timezone has been automatically set to {{activeTimezone}}.</p>
+{{/if}}
+<p>The local time here is currently {{localTime}}</p>

ghost/admin/app/templates/settings/general.hbs

@@ -113,21 +113,10 @@
                     {{/gh-form-group}}
                 </div>
 
-                <div class="form-group for-select">
-                    <label for="activeTimezone">Timezone</label>
-                    <span class="gh-select" data-select-text="{{selectedTimezone.label}}" tabindex="0">
-                        {{gh-select-native
-                            id="activeTimezone"
-                            name="general[activeTimezone]"
-                            content=availableTimezones
-                            optionValuePath="name"
-                            optionLabelPath="label"
-                            selection=selectedTimezone
-                            action="setTimezone"
-                        }}
-                    </span>
-                    <p>The local time here is currently {{localTime}}</p>
-                </div>
+                {{gh-timezone-select
+                        activeTimezone=model.activeTimezone
+                        availableTimezones=availableTimezones
+                        update=(action "setTimezone")}}
 
                 <div class="form-group for-checkbox">
                     <label for="isPrivate">Make this blog private</label>

ghost/admin/tests/integration/components/gh-timezone-select-test.js

@@ -0,0 +1,78 @@
+/* jshint expr:true */
+import { expect } from 'chai';
+import {
+    describeComponent,
+    it
+} from 'ember-mocha';
+import hbs from 'htmlbars-inline-precompile';
+import run from 'ember-runloop';
+import wait from 'ember-test-helpers/wait';
+import sinon from 'sinon';
+
+describeComponent(
+    'gh-timezone-select',
+    'Integration: Component: gh-timezone-select',
+    {
+        integration: true
+    },
+    function() {
+        beforeEach(function () {
+            this.set('availableTimezones', [
+                {name: 'Pacific/Pago_Pago', label: '(GMT -11:00) Midway Island, Samoa'},
+                {name: 'Etc/UTC', label: '(GMT) UTC'},
+                {name: 'Pacific/Kwajalein', label: '(GMT +12:00) International Date Line West'}
+            ]);
+            this.set('activeTimezone', 'Etc/UTC');
+        });
+
+        it('renders', function () {
+            this.render(hbs`{{gh-timezone-select
+                availableTimezones=availableTimezones
+                activeTimezone=activeTimezone}}`);
+
+            expect(this.$(), 'top-level elements').to.have.length(1);
+            expect(this.$('option'), 'number of options').to.have.length(3);
+            expect(this.$('select').val(), 'selected option value').to.equal('Etc/UTC');
+        });
+
+        it('handles an unknown timezone', function () {
+            this.set('activeTimezone', 'Europe/London');
+
+            this.render(hbs`{{gh-timezone-select
+                availableTimezones=availableTimezones
+                activeTimezone=activeTimezone}}`);
+
+            // we have an additional blank option at the top
+            expect(this.$('option'), 'number of options').to.have.length(4);
+            // blank option is selected
+            expect(this.$('select').val(), 'selected option value').to.equal('');
+            // we indicate the manual override
+            expect(this.$('p').text()).to.match(/Your timezone has been automatically set to Europe\/London/);
+        });
+
+        it('triggers update action on change', function (done) {
+            let update = sinon.spy();
+            this.set('update', update);
+
+            this.render(hbs`{{gh-timezone-select
+                availableTimezones=availableTimezones
+                activeTimezone=activeTimezone
+                update=(action update)}}`);
+
+            run(() => {
+                this.$('select').val('Pacific/Pago_Pago').change();
+            });
+
+            wait().then(() => {
+                expect(update.calledOnce, 'update was called once').to.be.true;
+                expect(update.firstCall.args[0].name, 'update was passed new timezone')
+                    .to.equal('Pacific/Pago_Pago');
+                done();
+            });
+        });
+
+        // TODO: mock clock service, fake the time, test we have the correct
+        // local time and it changes alongside selection changes
+        it('renders local time');
+    }
+);