fix: allow booking the free part of a partly booked day

src/Booking/BoardPresenter.php

@@ -73,11 +73,18 @@ final readonly class BoardPresenter
 
         $byResource = [];
         foreach ($this->bookings->findForDate($selected, $time, $type) as $booking) {
-            // Several bookings can overlap the span on one resource once times are in play; the
-            // first is enough to colour the shape, and the tooltip lists them all.
             $byResource[$booking->getResource()->getId()][] = $booking;
         }
 
+        // One Spot per resource, carrying its own state and what is still free of the span --
+        // several bookings can overlap the span on one resource once times are in play.
+        $resources = $this->resources->findActiveByType($type);
+
+        $spots = [];
+        foreach ($resources as $resource) {
+            $spots[$resource->getId()] = Spot::for($resource, $byResource[$resource->getId()] ?? [], $time, $user);
+        }
+
         return [
             'type' => $type,
             'selected_date' => $selected,
@@ -85,8 +92,8 @@ final readonly class BoardPresenter
             'month_start' => $monthStart,
             'weeks' => $weeks,
             'is_past' => $selected < $today,
-            'resources' => $this->resources->findActiveByType($type),
-            'bookings_by_resource' => $byResource,
+            'resources' => $resources,
+            'spots' => $spots,
             'my_bookings_today' => $mine[$selected->format('Y-m-d')] ?? [],
         ];
     }

src/Booking/Spot.php

@@ -0,0 +1,95 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Booking;
+
+use App\Entity\Booking;
+use App\Entity\Resource;
+use App\Entity\User;
+
+/**
+ * One shape on the floor plan: a resource, what is booked on it within the board's span, and
+ * what is still free.
+ *
+ * The state decision lives here rather than in Twig so it can be tested directly -- it was wrong
+ * in the template once already.
+ */
+final readonly class Spot
+{
+    /**
+     * @param list<Booking>   $bookings overlapping the span, in start order
+     * @param list<TimeRange> $free     what is left of the span
+     */
+    private function __construct(
+        public Resource $resource,
+        public array $bookings,
+        public ?Booking $own,
+        public array $free,
+        public SpotState $state,
+    ) {
+    }
+
+    /**
+     * @param list<Booking> $bookings everything booked on this resource that overlaps $span
+     */
+    public static function for(Resource $resource, array $bookings, TimeRange $span, User $viewer): self
+    {
+        $own = null;
+        foreach ($bookings as $booking) {
+            if ($booking->belongsTo($viewer)) {
+                $own = $booking;
+
+                break;
+            }
+        }
+
+        $free = TimeRange::remaining($span, array_map(
+            static fn (Booking $booking): TimeRange => $booking->getTimeRange(),
+            $bookings,
+        ));
+
+        // Yours wins over partly-free: clicking your own booking should open it, and the same
+        // person can still take another window on the same resource from the edit modal's day.
+        $state = match (true) {
+            null !== $own => SpotState::MINE,
+            [] === $bookings => SpotState::FREE,
+            [] === $free => SpotState::TAKEN,
+            default => SpotState::PARTLY,
+        };
+
+        return new self($resource, $bookings, $own, $free, $state);
+    }
+
+    /**
+     * The longest free window, which is what the booking modal prefills -- so the suggested span
+     * is always one that can actually be booked.
+     */
+    public function suggested(): ?TimeRange
+    {
+        $longest = null;
+
+        foreach ($this->free as $range) {
+            if (null === $longest || $range->durationInMinutes() > $longest->durationInMinutes()) {
+                $longest = $range;
+            }
+        }
+
+        return $longest;
+    }
+
+    /** Whether a NEW booking can start here -- i.e. any of the span is still free. */
+    public function isBookable(): bool
+    {
+        return $this->state->isBookable();
+    }
+
+    /**
+     * Whether clicking the shape does anything. Wider than isBookable(): your own booking is
+     * clickable too, it just opens the edit modal instead of the create one.
+     */
+    public function isActionable(): bool
+    {
+        return SpotState::MINE === $this->state || $this->isBookable();
+    }
+}

src/Booking/SpotState.php

@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Booking;
+
+/**
+ * How one resource looks on the floor plan, for the day and span the board is showing.
+ *
+ * PARTLY exists because of a real bug: with only "free" and "taken", a desk booked 09:00-13:00
+ * looked identical to one booked all day on an all-day board, and was equally unclickable -- so
+ * nobody could book the afternoon without first knowing to narrow the span by hand.
+ */
+enum SpotState
+{
+    case FREE;
+    case PARTLY;
+    case TAKEN;
+    case MINE;
+
+    public function isBookable(): bool
+    {
+        return self::FREE === $this || self::PARTLY === $this;
+    }
+}

src/Booking/TimeRange.php

@@ -103,6 +103,52 @@ final readonly class TimeRange implements \Stringable
         return $this->startMinute < $other->endMinute && $other->startMinute < $this->endMinute;
     }
 
+    public function durationInMinutes(): int
+    {
+        return $this->endMinute - $this->startMinute;
+    }
+
+    /**
+     * What is left of $within once every range in $taken is removed.
+     *
+     * This is what makes a partly-booked resource bookable: the floor plan needs to know not
+     * "is anything booked here" but "is anything still free here", and the booking modal needs a
+     * span it can actually prefill without colliding.
+     *
+     * @param list<self> $taken may overlap each other and may reach outside $within
+     *
+     * @return list<self> the free sub-ranges, in order; empty when nothing is left
+     */
+    public static function remaining(self $within, array $taken): array
+    {
+        usort($taken, static fn (self $a, self $b): int => $a->startMinute <=> $b->startMinute);
+
+        $free = [];
+        $cursor = $within->startMinute;
+
+        foreach ($taken as $range) {
+            if ($range->endMinute <= $cursor) {
+                continue;
+            }
+
+            if ($range->startMinute > $cursor) {
+                $free[] = new self($cursor, min($range->startMinute, $within->endMinute));
+            }
+
+            $cursor = max($cursor, $range->endMinute);
+
+            if ($cursor >= $within->endMinute) {
+                return $free;
+            }
+        }
+
+        if ($cursor < $within->endMinute) {
+            $free[] = new self($cursor, $within->endMinute);
+        }
+
+        return $free;
+    }
+
     public function equals(self $other): bool
     {
         return $this->startMinute === $other->startMinute && $this->endMinute === $other->endMinute;

src/Controller/BookingController.php

@@ -9,6 +9,7 @@ use App\Booking\BoardPresenter;
 use App\Booking\BookingManager;
 use App\Booking\DateParam;
 use App\Booking\ResourceAlreadyBookedException;
+use App\Booking\Spot;
 use App\Booking\SeriesResult;
 use App\Booking\TimeRange;
 use App\Entity\Booking;
@@ -70,9 +71,17 @@ final class BookingController extends AbstractController
         $selected = DateParam::parseOrToday($date);
         $boardTime = BoardController::timeOf($request);
 
-        // Prefilled from whatever span the board is showing, so narrowing the board and then
-        // clicking a desk books exactly what was on screen.
-        $data = new BookingRequest($selected, $boardTime);
+        // Prefilled with the longest window still free inside the board's span -- NOT the span
+        // itself. On an all-day board a resource booked 09:00-13:00 would otherwise be offered
+        // as 00:00-24:00, collide with itself on submit, and leave the user exactly as stuck as
+        // before. Falls back to the board's span when nothing is booked at all.
+        $spot = Spot::for(
+            $resource,
+            $this->repository->findOverlapping($resource, $selected, $boardTime),
+            $boardTime,
+            $this->currentUser(),
+        );
+        $data = new BookingRequest($selected, $spot->suggested() ?? $boardTime);
 
         $form = $this->createForm(BookingType::class, $data, [
             'action' => $this->generateUrl('app_booking_new', ['id' => $resource->getId(), 'date' => $date] + $this->timeParameters($boardTime)),

src/Form/BookingRequest.php

@@ -37,20 +37,30 @@ final class BookingRequest
     {
         $this->date = $date;
 
-        if (null !== $time && !$time->isAllDay()) {
-            $this->allDay = false;
-            $this->startTime = self::timeOf($time->startMinute);
-            $this->endTime = self::timeOf($time->endMinute);
+        if (null === $time || $time->isAllDay()) {
+            return;
         }
+
+        $this->allDay = false;
+        // An edge that is open to the edge of the day is left blank rather than filled in:
+        // 24:00 has no representation in <input type="time"> at all, and a blank already means
+        // "to the end of the day" here, exactly as it does on the board's span picker.
+        $this->startTime = TimeRange::DAY_START === $time->startMinute ? null : self::timeOf($time->startMinute);
+        $this->endTime = TimeRange::DAY_END === $time->endMinute ? null : self::timeOf($time->endMinute);
     }
 
     public function timeRange(): TimeRange
     {
-        if ($this->allDay || null === $this->startTime || null === $this->endTime) {
+        if ($this->allDay || (null === $this->startTime && null === $this->endTime)) {
             return TimeRange::wholeDay();
         }
 
-        return TimeRange::fromTimes($this->startTime, $this->endTime);
+        // One-sided input is open to that edge of the day -- the same rule TimeRange::parse()
+        // applies to the board's ?from=&to= pair, so the two never disagree.
+        return TimeRange::fromMinutes(
+            null === $this->startTime ? TimeRange::DAY_START : self::minutesOf($this->startTime),
+            null === $this->endTime ? TimeRange::DAY_END : self::minutesOf($this->endTime),
+        );
     }
 
     public function repeats(): bool
@@ -66,10 +76,10 @@ final class BookingRequest
     public function validate(ExecutionContextInterface $context): void
     {
         if (!$this->allDay) {
-            foreach (['startTime' => $this->startTime, 'endTime' => $this->endTime] as $field => $value) {
-                if (null === $value) {
-                    $context->buildViolation('Bitte eine Uhrzeit angeben.')->atPath($field)->addViolation();
-                }
+            if (null === $this->startTime && null === $this->endTime) {
+                $context->buildViolation('Bitte eine Uhrzeit angeben oder „Ganzer Tag" wählen.')
+                    ->atPath('startTime')
+                    ->addViolation();
             }
 
             if (null !== $this->startTime && null !== $this->endTime

src/Form/BookingType.php

@@ -30,12 +30,14 @@ final class BookingType extends AbstractType
             ])
             ->add('startTime', TimeType::class, [
                 'label' => 'Von',
+                'help' => 'leer = ab Tagesbeginn',
                 'widget' => 'single_text',
                 'input' => 'datetime_immutable',
                 'required' => false,
             ])
             ->add('endTime', TimeType::class, [
                 'label' => 'Bis',
+                'help' => 'leer = bis Tagesende',
                 'widget' => 'single_text',
                 'input' => 'datetime_immutable',
                 'required' => false,

templates/board/_floorplan.html.twig

@@ -13,6 +13,7 @@
         <h2 class="!pb-0">{{ selected_date|format_datetime(pattern: 'EEEE, d. MMMM y') }}</h2>
         <div class="flex items-center gap-4 text-xs text-gray-500">
             <span class="flex items-center gap-1"><span class="w-3 h-3 rounded-sm bg-emerald-50 border-2 border-emerald-500"></span> frei</span>
+            <span class="flex items-center gap-1"><span class="w-3 h-3 rounded-sm bg-amber-50 border-2 border-amber-500"></span> teilweise frei</span>
             <span class="flex items-center gap-1"><span class="w-3 h-3 rounded-sm bg-gray-200 border-2 border-gray-400"></span> belegt</span>
             <span class="flex items-center gap-1"><span class="w-3 h-3 rounded-sm bg-primary border-2 border-primary-dark"></span> deine</span>
         </div>

templates/board/plan/_desk.html.twig

@@ -21,8 +21,8 @@
 
     {% for resource in resources %}
         {% if resource.svgElementId and geometry[resource.svgElementId] is defined %}
-            {{ plan.spot(resource, geometry[resource.svgElementId], 140, 70,
-                bookings_by_resource[resource.id]|default([]), selected_date, is_past, time_params) }}
+            {{ plan.spot(spots[resource.id], geometry[resource.svgElementId], 140, 70,
+                selected_date, is_past, time_params) }}
         {% endif %}
     {% endfor %}
 </svg>

templates/board/plan/_parking.html.twig

@@ -18,8 +18,8 @@
 
     {% for resource in resources %}
         {% if resource.svgElementId and geometry[resource.svgElementId] is defined %}
-            {{ plan.spot(resource, geometry[resource.svgElementId], 200, 55,
-                bookings_by_resource[resource.id]|default([]), selected_date, is_past, time_params) }}
+            {{ plan.spot(spots[resource.id], geometry[resource.svgElementId], 200, 55,
+                selected_date, is_past, time_params) }}
         {% endif %}
     {% endfor %}
 </svg>

templates/board/plan/_spot.html.twig

@@ -1,59 +1,69 @@
 {#
     The shared shape a plan is drawn from. Imported by each board/plan/_<type>.html.twig, so the
-    per-type partials carry geometry only and free/taken/yours looks identical everywhere.
+    per-type partials carry geometry only and the states look identical everywhere.
 
-    Clicking always opens a modal: the create modal when free, the edit modal when it is yours
-    (which is where changing the times and releasing live). Nothing else is clickable, so the SVG
-    carries no confirm dialogs or inline CSRF tokens.
+    The state comes from App\Booking\Spot, not from counting bookings here. That distinction is
+    the fix for a real bug: a desk booked 09:00-13:00 used to render exactly like one booked all
+    day on an all-day board, and carried no hx-get either -- so a second person could not book the
+    afternoon at all unless they happened to narrow the span by hand first.
+
+    Clicking always opens a modal: the create modal when anything is still free, the edit modal
+    when it is yours (which is where changing the times and releasing live). Nothing else is
+    clickable, so the SVG carries no confirm dialogs or inline CSRF tokens.
 #}
-{% macro spot(resource, geometry, width, height, bookings, selected_date, is_past, time_params) %}
-    {% set own = bookings|filter(b => b.user.id == app.user.id)|first|default(null) %}
-    {% set mine = own is not null %}
+{% macro spot(spot, geometry, width, height, selected_date, is_past, time_params) %}
+    {% set state = spot.state.name %}
 
-    {% if mine %}
+    {% if state == 'MINE' %}
         {% set fill = 'fill-primary' %}{% set stroke = 'stroke-primary-dark' %}{% set text = 'fill-white' %}
-    {% elseif bookings is not empty %}
+    {% elseif state == 'TAKEN' %}
         {% set fill = 'fill-gray-200' %}{% set stroke = 'stroke-gray-400' %}{% set text = 'fill-gray-600' %}
+    {% elseif state == 'PARTLY' %}
+        {% set fill = 'fill-amber-50' %}{% set stroke = 'stroke-amber-500' %}{% set text = 'fill-amber-900' %}
     {% else %}
         {% set fill = 'fill-emerald-50' %}{% set stroke = 'stroke-emerald-500' %}{% set text = 'fill-emerald-900' %}
     {% endif %}
 
-    {% set interactive = not is_past and (mine or bookings is empty) %}
+    {% set interactive = not is_past and spot.actionable %}
 
-    {# Several bookings can overlap the board's span once part-day bookings exist, so the shape
-       counts them and the tooltip spells them out. #}
-    {% if mine %}
-        {% set caption = own.timeRange.allDay ? 'du' : 'du ' ~ own.timeRange %}
-    {% elseif bookings|length > 1 %}
-        {% set caption = bookings|length ~ ' Buchungen' %}
-    {% elseif bookings is not empty %}
-        {% set caption = bookings|first.user.name %}
+    {# The second line: what you would be told at a glance. For a partly-free spot that is the
+       window still available, because that is the reason to click it. #}
+    {% if state == 'MINE' %}
+        {% set caption = spot.own.timeRange.allDay ? 'du' : 'du ' ~ spot.own.timeRange %}
+    {% elseif state == 'PARTLY' %}
+        {% set caption = 'frei ' ~ spot.suggested %}
+    {% elseif spot.bookings|length > 1 %}
+        {% set caption = spot.bookings|length ~ ' Buchungen' %}
+    {% elseif spot.bookings is not empty %}
+        {% set caption = spot.bookings|first.user.name %}
     {% else %}
         {% set caption = null %}
     {% endif %}
 
     <g class="{{ interactive ? 'cursor-pointer' : 'cursor-default' }}"
-       {%- if interactive and mine %}
-           hx-get="{{ path('app_booking_edit', { id: own.id }|merge(time_params)) }}"
+       {%- if interactive and state == 'MINE' %}
+           hx-get="{{ path('app_booking_edit', { id: spot.own.id }|merge(time_params)) }}"
            hx-target="body"
            hx-swap="beforeend"
        {%- elseif interactive %}
-           {# The modal is appended to the end of <body>; closing it is Stimulus, not htmx. #}
-           hx-get="{{ path('app_booking_new', { id: resource.id, date: selected_date|date('Y-m-d') }|merge(time_params)) }}"
+           {# The modal is appended to the end of <body>; closing it is Stimulus, not htmx.
+              It prefills the free window itself -- see BookingController::create. #}
+           hx-get="{{ path('app_booking_new', { id: spot.resource.id, date: selected_date|date('Y-m-d') }|merge(time_params)) }}"
            hx-target="body"
            hx-swap="beforeend"
        {%- endif %}>
         <title>
-            {{- resource.label }}
-            {%- if bookings is empty %} — frei
+            {{- spot.resource.label }}
+            {%- if spot.bookings is empty %} — frei
             {%- else %}
-                {%- for booking in bookings %} — {{ booking.user.id == app.user.id ? 'du' : booking.user.name }} {{ booking.timeRange }}{% endfor %}
+                {%- for booking in spot.bookings %} — {{ booking.user.id == app.user.id ? 'du' : booking.user.name }} {{ booking.timeRange }}{% endfor %}
+                {%- for window in spot.free %} — frei {{ window }}{% endfor %}
             {%- endif -%}
         </title>
         <rect x="{{ geometry.x }}" y="{{ geometry.y }}" width="{{ width }}" height="{{ height }}" rx="6"
               class="{{ fill }} {{ stroke }}" stroke-width="2"></rect>
         <text x="{{ geometry.x + width / 2 }}" y="{{ geometry.y + (caption ? height / 2 - 4 : height / 2 + 4) }}"
-              text-anchor="middle" class="{{ text }} text-xs font-semibold">{{ resource.label }}</text>
+              text-anchor="middle" class="{{ text }} text-xs font-semibold">{{ spot.resource.label }}</text>
         {% if caption %}
             <text x="{{ geometry.x + width / 2 }}" y="{{ geometry.y + height / 2 + 12 }}"
                   text-anchor="middle" class="{{ text }} text-[10px]">{{ caption }}</text>

templates/security/login.html.twig

@@ -7,23 +7,22 @@
         <div class="w-full max-w-md text-center">
             <img class="h-8 w-auto mx-auto mb-8" src="{{ asset('images/logo_ep.svg') }}" alt="ephub">
 
-            <h1>Anmelden</h1>
-            <p class="subline pb-8">Schreibtische und Parkplätze buchen.</p>
+            <h1>
+                Login E&P Hub
+            </h1>
+            <p class="subline pb-8">
+                Schreibtische und Parkplätze buchen.
+            </p>
 
-            {% if oauth2_configured %}
-                <a class="button button--primary w-full" href="{{ path('app_auth_init') }}">
-                    Mit myep anmelden
-                </a>
-            {% else %}
-                <div class="rounded-md border border-amber-300 bg-amber-50 px-4 py-3 text-sm text-left">
-                    <strong>Anmeldung noch nicht eingerichtet.</strong>
-                    Für ephub muss auf myep erst ein OAuth2-Client registriert werden.
-                </div>
-            {% endif %}
+            <a class="button button--primary w-full" href="{{ path('app_auth_init') }}">
+                Mit myep anmelden
+            </a>
 
             {% if app.environment == 'dev' %}
                 <p class="pt-6 text-sm">
-                    <a class="underline text-gray-500" href="{{ path('app_dev_login') }}">Entwickler-Login</a>
+                    <a class="underline text-gray-500" href="{{ path('app_dev_login') }}">
+                        Entwickler-Login
+                    </a>
                 </p>
             {% endif %}
 

tests/Booking/SpotTest.php

@@ -0,0 +1,166 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Tests\Booking;
+
+use App\Booking\Spot;
+use App\Booking\SpotState;
+use App\Booking\TimeRange;
+use App\Entity\Booking;
+use App\Entity\Resource;
+use App\Entity\ResourceType;
+use App\Entity\User;
+use PHPUnit\Framework\TestCase;
+
+class SpotTest extends TestCase
+{
+    public function testAResourceWithNothingBookedIsFree(): void
+    {
+        $spot = $this->spot([]);
+
+        self::assertSame(SpotState::FREE, $spot->state);
+        self::assertTrue($spot->isBookable());
+        self::assertNull($spot->own);
+    }
+
+    /**
+     * The reported bug: somebody else holds 09:00-13:00, the board shows the whole day, and the
+     * afternoon is still bookable. This used to come out as TAKEN and carried no link at all.
+     */
+    public function testAResourceBookedForPartOfTheDayIsStillBookable(): void
+    {
+        $spot = $this->spot([$this->booking($this->someoneElse(), 540, 780)]);
+
+        self::assertSame(SpotState::PARTLY, $spot->state);
+        self::assertTrue($spot->isBookable());
+        self::assertTrue($spot->isActionable());
+    }
+
+    public function testTheSuggestedWindowIsTheLongestFreeOne(): void
+    {
+        // Taken 09:00-13:00 leaves 00:00-09:00 (9h) and 13:00-24:00 (11h).
+        $spot = $this->spot([$this->booking($this->someoneElse(), 540, 780)]);
+
+        self::assertSame('13:00–24:00', (string) $spot->suggested());
+    }
+
+    public function testTheSuggestedWindowIsAlwaysBookable(): void
+    {
+        $taken = $this->booking($this->someoneElse(), 540, 780);
+        $spot = $this->spot([$taken]);
+
+        // The whole point of suggesting a gap rather than the board's span: submitting it must
+        // not collide with what is already there.
+        self::assertFalse($spot->suggested()->overlaps($taken->getTimeRange()));
+    }
+
+    public function testAResourceBookedAllDayIsTaken(): void
+    {
+        $spot = $this->spot([$this->booking($this->someoneElse(), 0, 1440)]);
+
+        self::assertSame(SpotState::TAKEN, $spot->state);
+        self::assertFalse($spot->isBookable());
+        self::assertFalse($spot->isActionable());
+        self::assertNull($spot->suggested());
+    }
+
+    public function testSeveralBookingsCanLeaveNothingFree(): void
+    {
+        $spot = $this->spot([
+            $this->booking($this->someoneElse(), 0, 720),
+            $this->booking($this->someoneElse(), 720, 1440),
+        ]);
+
+        self::assertSame(SpotState::TAKEN, $spot->state);
+    }
+
+    public function testSeveralBookingsCanStillLeaveAGapBetweenThem(): void
+    {
+        $spot = $this->spot([
+            $this->booking($this->someoneElse(), 0, 540),
+            $this->booking($this->someoneElse(), 780, 1440),
+        ]);
+
+        self::assertSame(SpotState::PARTLY, $spot->state);
+        self::assertSame('09:00–13:00', (string) $spot->suggested());
+    }
+
+    public function testYourOwnBookingWinsOverEverythingElse(): void
+    {
+        $viewer = $this->viewer();
+        $spot = Spot::for(
+            $this->resource(),
+            [$this->booking($viewer, 540, 780)],
+            TimeRange::wholeDay(),
+            $viewer,
+        );
+
+        self::assertSame(SpotState::MINE, $spot->state);
+        // Clicking opens the edit modal rather than the create one, so it is actionable but not
+        // offered as a new booking.
+        self::assertTrue($spot->isActionable());
+        self::assertNotNull($spot->own);
+    }
+
+    /**
+     * A narrowed board only asks about its own window, so what happens outside it is irrelevant.
+     */
+    public function testStateIsJudgedWithinTheBoardsSpanOnly(): void
+    {
+        $spot = Spot::for(
+            $this->resource(),
+            [],
+            TimeRange::fromMinutes(780, 1020),
+            $this->viewer(),
+        );
+
+        self::assertSame(SpotState::FREE, $spot->state);
+        self::assertSame('13:00–17:00', (string) $spot->suggested());
+    }
+
+    /**
+     * @param list<Booking> $bookings
+     */
+    private function spot(array $bookings): Spot
+    {
+        return Spot::for($this->resource(), $bookings, TimeRange::wholeDay(), $this->viewer());
+    }
+
+    private function booking(User $user, int $start, int $end): Booking
+    {
+        return new Booking($user, $this->resource(), new \DateTimeImmutable('2026-10-01'), TimeRange::fromMinutes($start, $end));
+    }
+
+    private function resource(): Resource
+    {
+        return new Resource(ResourceType::DESK, 'D1', 'desk-01');
+    }
+
+    private function viewer(): User
+    {
+        return new UserWithId('[email protected]', 'Anna', 1);
+    }
+
+    private function someoneElse(): User
+    {
+        return new UserWithId('[email protected]', 'Bea', 2);
+    }
+}
+
+/**
+ * Spot compares users by id, and an unpersisted User has none -- which would make every booking
+ * look like everyone's. This gives the fixtures stable ids without touching the database.
+ */
+class UserWithId extends User
+{
+    public function __construct(string $email, string $name, private readonly int $fixedId)
+    {
+        parent::__construct($email, $name);
+    }
+
+    public function getId(): ?int
+    {
+        return $this->fixedId;
+    }
+}

tests/Booking/TimeRangeTest.php

@@ -83,6 +83,57 @@ class TimeRangeTest extends TestCase
         yield 'out of range is rejected' => ['25:00', '26:00', null];
     }
 
+    public function testRemainingIsTheWholeSpanWhenNothingIsTaken(): void
+    {
+        $free = TimeRange::remaining(TimeRange::wholeDay(), []);
+
+        self::assertSame(['00:00–24:00'], self::render($free));
+    }
+
+    public function testRemainingSplitsAroundABookingInTheMiddle(): void
+    {
+        $free = TimeRange::remaining(TimeRange::wholeDay(), [TimeRange::fromMinutes(540, 780)]);
+
+        self::assertSame(['00:00–09:00', '13:00–24:00'], self::render($free));
+    }
+
+    public function testRemainingIsEmptyWhenTheSpanIsFullyCovered(): void
+    {
+        self::assertSame([], TimeRange::remaining(TimeRange::wholeDay(), [TimeRange::wholeDay()]));
+    }
+
+    public function testRemainingHandlesOverlappingAndUnsortedInput(): void
+    {
+        // Bookings on one resource cannot overlap, but the span may be covered by several that
+        // touch, and nothing guarantees the order they arrive in.
+        $free = TimeRange::remaining(TimeRange::wholeDay(), [
+            TimeRange::fromMinutes(780, 1020),
+            TimeRange::fromMinutes(540, 900),
+        ]);
+
+        self::assertSame(['00:00–09:00', '17:00–24:00'], self::render($free));
+    }
+
+    public function testRemainingIgnoresWhatFallsOutsideTheSpan(): void
+    {
+        $free = TimeRange::remaining(TimeRange::fromMinutes(780, 1020), [TimeRange::fromMinutes(0, 540)]);
+
+        self::assertSame(['13:00–17:00'], self::render($free));
+    }
+
+    public function testRemainingClipsABookingThatOverhangsTheSpan(): void
+    {
+        $free = TimeRange::remaining(TimeRange::fromMinutes(480, 1080), [TimeRange::fromMinutes(0, 600)]);
+
+        self::assertSame(['10:00–18:00'], self::render($free));
+    }
+
+    public function testDurationIsInMinutes(): void
+    {
+        self::assertSame(240, TimeRange::fromMinutes(540, 780)->durationInMinutes());
+        self::assertSame(1440, TimeRange::wholeDay()->durationInMinutes());
+    }
+
     /**
      * Regression guard for a trap that cost real debugging time: Twig resolves `range.allDay` by
      * looking for a method literally named `allDay` BEFORE it tries `isAllDay()`, and it happily
@@ -97,4 +148,14 @@ class TimeRangeTest extends TestCase
         self::assertSame('no', $twig->render('t', ['range' => TimeRange::fromMinutes(9 * 60, 13 * 60)]));
         self::assertSame('yes', $twig->render('t', ['range' => TimeRange::wholeDay()]));
     }
+
+    /**
+     * @param list<TimeRange> $ranges
+     *
+     * @return list<string>
+     */
+    private static function render(array $ranges): array
+    {
+        return array_map(static fn (TimeRange $range): string => $range->start().'–'.$range->end(), $ranges);
+    }
 }

tests/Controller/BookingControllerTest.php

@@ -210,6 +210,56 @@ class BookingControllerTest extends WebTestCase
         self::assertCount(1, $crawler->filter(\sprintf('[hx-get="/bookings/%d/edit"]', $booking->getId())));
     }
 
+    /**
+     * The reported bug, end to end: one person holds 09:00-13:00, a second opens the board on
+     * its default all-day span, and must be able to take the rest of the day.
+     *
+     * The plan used to render that desk exactly like a fully booked one and give it no hx-get at
+     * all, so the second person could not reach the modal unless they happened to narrow the
+     * span by hand first.
+     */
+    public function testASecondPersonCanBookTheRestOfADayFromTheDefaultBoard(): void
+    {
+        $desk = $this->resource('D1', svgElementId: 'desk-01');
+        $this->em->persist(new Booking($this->user('[email protected]'), $desk, new \DateTimeImmutable('2026-10-01'), TimeRange::fromMinutes(540, 780)));
+        $this->em->flush();
+
+        $this->client->loginUser($this->user('[email protected]'));
+
+        // 1. The shape is clickable on the all-day board.
+        $crawler = $this->client->request('GET', '/book/desk?date=2026-10-01');
+        $opener = $crawler->filter(\sprintf('g[hx-get*="/bookings/new/%d/"]', $desk->getId()));
+        self::assertCount(1, $opener, 'a partly booked desk must still open the booking modal');
+
+        // 2. The modal it opens is prefilled with a window that is actually free.
+        $modal = $this->client->request('GET', $opener->attr('hx-get'), server: ['HTTP_HX-Request' => 'true']);
+        self::assertSame('13:00', $modal->filter('#booking_startTime')->attr('value'));
+        // Blank, not 24:00 -- <input type="time"> cannot hold it, and blank already means
+        // "to the end of the day" here just as it does on the board's span picker.
+        self::assertNull($modal->filter('#booking_endTime')->attr('value'));
+
+        // 3. Submitting it works.
+        $response = $this->submitBookingModal($desk, '2026-10-01', [
+            'startTime' => '13:00',
+            'endTime' => '17:00',
+        ]);
+
+        self::assertSame(Response::HTTP_OK, $response->getStatusCode());
+        self::assertCount(2, $this->em->getRepository(Booking::class)->findBy(['resource' => $desk]));
+    }
+
+    public function testAFullyBookedDeskIsNotClickable(): void
+    {
+        $desk = $this->resource('D1', svgElementId: 'desk-01');
+        $this->em->persist(new Booking($this->user('[email protected]'), $desk, new \DateTimeImmutable('2026-10-01')));
+        $this->em->flush();
+
+        $this->client->loginUser($this->user('[email protected]'));
+        $crawler = $this->client->request('GET', '/book/desk?date=2026-10-01');
+
+        self::assertCount(0, $crawler->filter(\sprintf('g[hx-get*="/bookings/new/%d/"]', $desk->getId())));
+    }
+
     public function testBookingPartOfADay(): void
     {
         $this->client->loginUser($this->user('[email protected]'));