import {
  listGroupedStockEntries,
  listKitchenChanges,
  listStockEntries,
  updateStockItem,
  useStockItem,
} from '../../api/stock.js';
import { fetchLocations } from '../../api/locations.js';
import { createAsyncState } from '../shared/ui-state.js';
import { formatDate } from '../shared/date-utils.js';

const LEVEL_LABELS = {
  plenty: 'Plenty',
  good: 'Good',
  some: 'Some',
  low: 'Low',
  trace: 'Trace',
  gone: 'Gone',
};

const LEVEL_OPTIONS = [
  { value: 'plenty', label: 'Plenty' },
  { value: 'good', label: 'Good' },
  { value: 'some', label: 'Some' },
  { value: 'low', label: 'Low' },
  { value: 'trace', label: 'Trace' },
  { value: 'gone', label: 'Gone' },
];

const EXPIRATION_LEGEND = [
  { key: 'expired', label: 'Expired', description: 'The expiration date has already passed.' },
  { key: 'use-first', label: 'Use first', description: 'Still within date, but should be prioritized soonest for consumption.' },
  { key: 'upcoming', label: 'Upcoming expiration', description: 'Within date, but approaching expiration in the near term.' },
  { key: 'within-date', label: 'Within date', description: 'Still within the expected shelf-life window.' },
  { key: 'none', label: 'No expiration', description: 'No expiration date is assigned.' },
];

const EXPIRATION_KEYS = EXPIRATION_LEGEND.map((state) => state.key);
const GROUPED_PAGE_SIZE = 24;
const CHANGE_POLL_INTERVAL_MS = 60 * 1000;

function todayAtMidnight() {
  const now = new Date();
  return new Date(now.getFullYear(), now.getMonth(), now.getDate());
}

function parseDateValue(value) {
  if (!value) {
    return null;
  }

  const [year, month, day] = value.split('-').map(Number);
  if (!year || !month || !day) {
    return null;
  }

  return new Date(year, month - 1, day);
}

function expirationInfo(entry) {
  const expireDateValue =
    Array.isArray(entry.items) && (entry.first_expire_date || entry.first_expire_in !== undefined)
      ? entry.first_expire_date || entry.expire_date
      : entry.expire_date;
  const expireInValue =
    Array.isArray(entry.items) && entry.first_expire_in !== undefined
      ? entry.first_expire_in
      : entry.expire_in;

  if (!expireDateValue) {
    return {
      key: 'none',
      label: 'No expiration date',
      detail: 'No expiration date',
      sortRank: 4,
    };
  }

  const today = todayAtMidnight();
  const expireDate = parseDateValue(expireDateValue);
  const expireIn =
    typeof expireInValue === 'number'
      ? expireInValue
      : expireDate
        ? Math.round((expireDate - today) / (24 * 60 * 60 * 1000))
        : null;

  if (expireIn < 0) {
    return {
      key: 'expired',
      label: 'Expired',
      detail: `Expired ${Math.abs(expireIn)} day${Math.abs(expireIn) === 1 ? '' : 's'} ago`,
      sortRank: 0,
    };
  }

  if (expireIn <= 2) {
    return {
      key: 'use-first',
      label: expireIn === 0 ? 'Use today' : 'Use first',
      detail:
        expireIn === 0
          ? 'Expires today'
          : `Expires in ${expireIn} day${expireIn === 1 ? '' : 's'}`,
      sortRank: 1,
    };
  }

  if (expireIn <= 7) {
    return {
      key: 'upcoming',
      label: 'Upcoming expiration',
      detail: `Expires in ${expireIn} days`,
      sortRank: 2,
    };
  }

  return {
    key: 'within-date',
    label: 'Within date',
    detail: `Expires in ${expireIn} days`,
    sortRank: 3,
  };
}

function sortEntries(entries) {
  return [...entries].sort((left, right) => {
    const leftExpiration = expirationInfo(left);
    const rightExpiration = expirationInfo(right);

    if (leftExpiration.sortRank !== rightExpiration.sortRank) {
      return leftExpiration.sortRank - rightExpiration.sortRank;
    }

    const leftExpire = left.expire_date || '9999-12-31';
    const rightExpire = right.expire_date || '9999-12-31';
    if (leftExpire !== rightExpire) {
      return leftExpire.localeCompare(rightExpire);
    }

    return (left.name || '').localeCompare(right.name || '');
  });
}

function sortGroupedEntries(groups) {
  return [...groups].sort((left, right) => {
    const leftExpiration = expirationInfo(left);
    const rightExpiration = expirationInfo(right);

    if (leftExpiration.sortRank !== rightExpiration.sortRank) {
      return leftExpiration.sortRank - rightExpiration.sortRank;
    }

    const leftExpire = left.first_expire_date || left.expire_date || '9999-12-31';
    const rightExpire = right.first_expire_date || right.expire_date || '9999-12-31';
    if (leftExpire !== rightExpire) {
      return leftExpire.localeCompare(rightExpire);
    }

    return (left.name || '').localeCompare(right.name || '');
  });
}

function quantityLabel(entry) {
  if (entry.stock_type === 'binary') {
    return entry.level === 'gone' ? 'Gone' : 'Available';
  }

  const numeric = entry.quantity ?? null;
  const uom = entry.uom_symbol || '';
  const measured = numeric !== null && numeric !== undefined ? `${numeric} ${uom}`.trim() : '';
  const level = entry.level ? LEVEL_LABELS[entry.level] || entry.level : '';

  if (entry.stock_type === 'descriptive') {
    return level || 'No stock level';
  }

  if (measured && level) {
    return `${measured} • ${level}`;
  }

  return measured || level || 'No quantity';
}

function resolveLocationLabel(entry, locationMap) {
  if (!entry.location_initial_uuid_b64) {
    return 'No location assigned';
  }

  return locationMap[entry.location_initial_uuid_b64] || 'Location not resolved';
}

function searchBlob(entry, locationMap) {
  return [
    entry.name,
    entry.description,
    entry.level,
    entry.stock_type,
    resolveLocationLabel(entry, locationMap),
    entry.uuid_b64,
  ]
    .filter(Boolean)
    .join(' ')
    .toLowerCase();
}

function groupSearchBlob(group, locationMap) {
  return [
    searchBlob(group, locationMap),
    ...(group.items || []).map((item) => searchBlob(item, locationMap)),
  ]
    .filter(Boolean)
    .join(' ')
    .toLowerCase();
}

function groupedPrimaryDate(group) {
  return group.date;
}

function groupedFirstProductionDate(group) {
  return group.first_production_date || group.date;
}

function groupedFirstExpireDate(group) {
  return group.first_expire_date || group.expire_date;
}

function shortDescription(value, maxLength = 24) {
  if (!value) {
    return 'No description';
  }

  if (value.length <= maxLength) {
    return value;
  }

  return `${value.slice(0, maxLength).trimEnd()}...`;
}

export function renderStockListPage() {
  return `
    <section class="container-xxl py-4 py-lg-5" x-data="stockListPage()" x-init="init()">
      <div class="d-flex flex-column flex-lg-row justify-content-between gap-3 align-items-lg-end mb-4">
        <div>
          <p class="eyebrow mb-2">Stock Review</p>
          <h1 class="h3 mb-1">Review stock and act quickly</h1>
          <p class="text-body-secondary mb-0">
            Focus on expiration, stock state, and location without leaving the overview.
          </p>
        </div>
        <a href="#/labels/new" class="btn btn-primary">New stock label</a>
      </div>

      <div class="card border-0 shadow-sm mb-4">
        <div class="card-body p-3">
          <div class="d-flex flex-column flex-xl-row justify-content-between align-items-xl-center gap-3">
            <div class="stock-view-switch-wrap">
              <div class="small text-body-secondary fw-semibold mb-2">Stock view mode</div>
              <div class="stock-view-switch" role="tablist" aria-label="Stock view mode">
                <button
                  class="stock-view-tab"
                  type="button"
                  role="tab"
                  :class="viewMode === 'grouped' ? 'stock-view-tab-active' : ''"
                  :aria-selected="viewMode === 'grouped'"
                  @click="switchView('grouped')"
                >
                  <span class="stock-view-tab-title">Grouped stock</span>
                  <span class="stock-view-tab-subtitle">Fast overview by product group</span>
                </button>
                <button
                  class="stock-view-tab"
                  type="button"
                  role="tab"
                  :class="viewMode === 'items' ? 'stock-view-tab-active' : ''"
                  :aria-selected="viewMode === 'items'"
                  @click="switchView('items')"
                >
                  <span class="stock-view-tab-title">Individual items</span>
                  <span class="stock-view-tab-subtitle">Detailed per-item adjustments</span>
                </button>
              </div>
            </div>
            <div>
              <button
                class="btn btn-outline-secondary"
                type="button"
                @click="refreshCurrentView()"
                :disabled="state.isLoading || state.isRefreshing"
              >
                <span x-show="!state.isLoading && !state.isRefreshing">Refresh</span>
                <span x-show="state.isLoading || state.isRefreshing">Refreshing...</span>
              </button>
            </div>
          </div>
          <div class="small text-body-secondary mt-2" x-show="state.isRefreshing && !state.isLoading">
            Updating in background...
          </div>
        </div>
      </div>

      <div class="row g-4 stock-workspace">
        <aside class="col-12 col-xl-4 col-xxl-3 stock-filter-rail">
          <div class="card border-0 shadow-sm stock-filter-hub">
            <div class="card-body p-4">
              <div class="d-flex flex-column gap-2 mb-3">
                <div>
                  <h2 class="h5 mb-1">Search and filters</h2>
                  <p class="text-body-secondary small mb-0">
                    Focus the stock list with one control panel.
                  </p>
                </div>
                <div class="d-flex justify-content-between align-items-center">
                  <button class="btn btn-link p-0 text-decoration-none stock-filter-reset" type="button" @click="clearFilters()">Reset all</button>
                  <div class="small text-body-secondary text-end">
                    <span class="fw-semibold text-body" x-text="visibleResultCount"></span>
                    <span x-text="viewMode === 'grouped' ? 'group(s)' : 'item(s)'"></span>
                  </div>
                </div>
              </div>

              <div class="mb-3">
                <label class="form-label mb-1">Search stock</label>
                <input
                  class="form-control"
                  type="text"
                  x-model.debounce.250ms="filters.search"
                  placeholder="Search by item, description, location, or id"
                />
              </div>

              <div class="stock-filter-summary mb-3">
                <div class="small text-body-secondary mb-2">Active scope</div>
                <div class="d-grid gap-1">
                  <div class="small"><span class="fw-semibold">Expiration:</span> <span x-text="expirationFilterSummary()"></span></div>
                  <div class="small"><span class="fw-semibold">Location:</span> <span x-text="locationFilterSummary()"></span></div>
                </div>
              </div>

              <div
                class="d-grid gap-3 stock-filter-panels"
                :class="{ 'stock-filter-panels-single-open': openOverviewCount() > 0 }"
              >
                <details
                  class="overview-panel stock-filter-panel-card"
                  x-ref="expirationOverview"
                  @toggle="setOverviewOpen('expiration', $event.target.open)"
                >
                  <summary class="p-3 overview-summary">
                    <div class="d-flex justify-content-between align-items-start gap-3">
                      <div>
                        <h3 class="h6 mb-1">Expiration overview</h3>
                        <p class="text-body-secondary small mb-0">Tap to focus expiration states.</p>
                      </div>
                      <button class="btn btn-link p-0 text-decoration-none stock-filter-reset" type="button" @click.prevent.stop="toggleAllExpirationFilters()">Show all</button>
                    </div>
                  </summary>
                  <div class="pt-0 px-3 pb-3">
                    <div class="overview-list">
                      <template x-for="stateInfo in expirationLegend" :key="stateInfo.key">
                        <button
                          class="overview-option text-start"
                          type="button"
                          :class="legendClass(stateInfo.key)"
                          @click="toggleExpirationOverviewFilter(stateInfo.key)"
                          :aria-pressed="isExpirationFilterActive(stateInfo.key)"
                        >
                          <div class="d-flex justify-content-between align-items-start gap-3 mb-1">
                            <div class="fw-semibold" x-text="stateInfo.label"></div>
                            <div class="small fw-semibold" x-text="expirationCount(stateInfo.key)"></div>
                          </div>
                          <div class="small" x-text="stateInfo.description"></div>
                        </button>
                      </template>
                    </div>
                  </div>
                </details>

                <details
                  class="overview-panel stock-filter-panel-card"
                  x-ref="locationOverview"
                  @toggle="setOverviewOpen('location', $event.target.open)"
                >
                  <summary class="p-3 overview-summary">
                    <div class="d-flex justify-content-between align-items-start gap-3">
                      <div>
                        <h3 class="h6 mb-1">Location overview</h3>
                        <p class="text-body-secondary small mb-0">Parent locations include children.</p>
                      </div>
                      <button class="btn btn-link p-0 text-decoration-none stock-filter-reset" type="button" @click.prevent.stop="toggleAllLocations()">Show all</button>
                    </div>
                  </summary>
                  <div class="pt-0 px-3 pb-3">
                    <template x-if="isOnlyOverviewOpen('location')">
                      <div class="overview-list overview-list-locations location-overview-columns">
                        <template x-for="(columnGroups, columnIndex) in balancedLocationOverviewColumns()" :key="columnIndex">
                          <div class="location-overview-column">
                            <template x-for="group in columnGroups" :key="group.parent.id">
                              <div class="location-overview-group">
                                <template x-for="location in group.items" :key="location.id">
                                  <button
                                    class="overview-option overview-option-location text-start"
                                    type="button"
                                    :class="locationOverviewClass(location)"
                                    :style="locationOverviewStyle(location)"
                                    @click="toggleLocationOverviewFilter(location.uuid_b64)"
                                    :aria-pressed="isLocationFilterActive(location.uuid_b64)"
                                  >
                                    <span class="stock-filter-location-rail" x-show="location.depth"></span>
                                    <div class="d-flex justify-content-between align-items-start gap-3">
                                      <div class="fw-semibold" :class="location.depth ? 'small mb-0' : ''" x-text="location.name"></div>
                                      <div class="small fw-semibold" x-text="locationCount(location.uuid_b64)"></div>
                                    </div>
                                  </button>
                                </template>
                              </div>
                            </template>
                          </div>
                        </template>
                      </div>
                    </template>
                    <template x-if="!isOnlyOverviewOpen('location')">
                      <div class="overview-list overview-list-locations">
                        <template x-for="group in locationOverviewGroups()" :key="group.parent.id">
                          <div class="location-overview-group">
                            <template x-for="location in group.items" :key="location.id">
                              <button
                                class="overview-option overview-option-location text-start"
                                type="button"
                                :class="locationOverviewClass(location)"
                                :style="locationOverviewStyle(location)"
                                @click="toggleLocationOverviewFilter(location.uuid_b64)"
                                :aria-pressed="isLocationFilterActive(location.uuid_b64)"
                              >
                                <span class="stock-filter-location-rail" x-show="location.depth"></span>
                                <div class="d-flex justify-content-between align-items-start gap-3">
                                  <div class="fw-semibold" :class="location.depth ? 'small mb-0' : ''" x-text="location.name"></div>
                                  <div class="small fw-semibold" x-text="locationCount(location.uuid_b64)"></div>
                                </div>
                              </button>
                            </template>
                          </div>
                        </template>
                      </div>
                    </template>
                  </div>
                </details>
              </div>
            </div>
          </div>
        </aside>

        <div class="col-12 col-xl-8 col-xxl-9 stock-results-pane">
      <template x-if="showInitialLoader()">
        <div class="alert alert-secondary">Loading stock review...</div>
      </template>

      <template x-if="state.error">
        <div class="alert alert-danger d-flex justify-content-between align-items-center gap-3">
          <span x-text="state.error"></span>
          <button class="btn btn-sm btn-outline-danger" type="button" @click="init()">Retry</button>
        </div>
      </template>

      <template x-if="!state.isLoading && !state.error && viewMode === 'items' && !filteredEntries.length">
        <div class="card border-0 shadow-sm">
          <div class="card-body p-4 text-center">
            <h2 class="h5">No stock items to show</h2>
            <p class="text-body-secondary mb-0">
              Try clearing the filters or create a new stock label.
            </p>
          </div>
        </div>
      </template>

      <template x-if="!state.isLoading && !state.error && viewMode === 'items' && filteredEntries.length">
        <div>
          <div class="d-none d-xl-block">
            <div class="card border-0 shadow-sm overflow-hidden">
              <div class="table-responsive">
                <table class="table align-middle mb-0 stock-review-table">
                  <thead class="table-light">
                    <tr>
                      <th>Item</th>
                      <th>Expiration</th>
                      <th>Quantity / level</th>
                      <th>Location</th>
                      <th>Dates</th>
                      <th>Quick actions</th>
                    </tr>
                  </thead>
                  <tbody>
                    <template x-for="entry in filteredEntries" :key="entry.id">
                      <tr :class="rowClass(entry)">
                        <td>
                          <div class="fw-semibold" x-text="entry.name"></div>
                          <div class="small text-body-secondary" x-text="entry.description || 'No description'"></div>
                          <div class="small font-monospace text-body-secondary" x-text="shortId(entry)"></div>
                          <a class="small text-decoration-none fw-semibold" :href="detailHref(entry)">View item</a>
                        </td>
                        <td>
                          <div class="d-flex align-items-center gap-2 mb-1">
                            <span class="badge rounded-pill" :class="badgeClass(entry)" x-text="expirationFor(entry).label"></span>
                          </div>
                          <div class="small text-body-secondary" x-text="expirationFor(entry).detail"></div>
                        </td>
                        <td>
                          <div class="fw-semibold" x-text="quantityLabel(entry)"></div>
                          <div class="small text-body-secondary" x-text="stockTypeDetail(entry)"></div>
                        </td>
                        <td x-text="locationLabel(entry)"></td>
                        <td>
                          <div class="small"><span class="text-body-secondary">Made:</span> <span x-text="formatDate(entry.date)"></span></div>
                          <div class="small"><span class="text-body-secondary">Expires:</span> <span x-text="formatDate(entry.expire_date)"></span></div>
                        </td>
                        <td>
                          <div class="quick-edit-stack">
                            <template x-if="entry.stock_type === 'binary'">
                              <div class="d-flex flex-wrap gap-2">
                                <button class="btn btn-sm btn-outline-danger" type="button" @click="updateBinary(entry, 'gone')">Mark gone</button>
                              </div>
                            </template>
                            <template x-if="entry.stock_type === 'descriptive'">
                              <div class="d-flex flex-wrap gap-2 align-items-center">
                                <select class="form-select form-select-sm quick-select" x-model="editForms[entry.id].level">
                                  <template x-for="option in levelOptions" :key="option.value">
                                    <option :value="option.value" x-text="option.label"></option>
                                  </template>
                                </select>
                                <button class="btn btn-sm btn-primary" type="button" @click="saveLevel(entry)">Save</button>
                                <button class="btn btn-sm btn-outline-danger" type="button" @click="markGone(entry)">Mark gone</button>
                              </div>
                            </template>
                            <template x-if="entry.stock_type === 'measured'">
                              <div class="d-flex flex-wrap gap-2 align-items-center">
                                <input class="form-control form-control-sm quick-number" type="number" step="0.01" min="0" x-model="editForms[entry.id].quantity" />
                                <button class="btn btn-sm btn-primary" type="button" @click="saveQuantity(entry)">Save qty</button>
                                <button class="btn btn-sm btn-outline-danger" type="button" @click="markGone(entry)">Mark gone</button>
                              </div>
                            </template>
                            <template x-if="editErrors[entry.id]">
                              <div class="small text-danger" x-text="editErrors[entry.id]"></div>
                            </template>
                          </div>
                        </td>
                      </tr>
                    </template>
                  </tbody>
                </table>
              </div>
            </div>
          </div>

          <div class="d-grid gap-3 d-xl-none">
            <template x-for="entry in filteredEntries" :key="entry.id">
              <div class="card border-0 shadow-sm stock-review-card" :class="rowClass(entry)">
                <div class="card-body p-4">
                  <div class="d-flex justify-content-between gap-3 align-items-start mb-3">
                    <div>
                      <div class="fw-semibold fs-5" x-text="entry.name"></div>
                      <div class="text-body-secondary small" x-text="entry.description || 'No description'"></div>
                      <div class="text-body-secondary small font-monospace" x-text="shortId(entry)"></div>
                      <a class="small text-decoration-none fw-semibold" :href="detailHref(entry)">View item</a>
                    </div>
                    <span class="badge rounded-pill" :class="badgeClass(entry)" x-text="expirationFor(entry).label"></span>
                  </div>

                  <div class="row g-3 small mb-3">
                    <div class="col-6">
                      <div class="text-body-secondary">Quantity / level</div>
                      <div class="fw-semibold" x-text="quantityLabel(entry)"></div>
                    </div>
                    <div class="col-6">
                      <div class="text-body-secondary">Location</div>
                      <div class="fw-semibold" x-text="locationLabel(entry)"></div>
                    </div>
                    <div class="col-6">
                      <div class="text-body-secondary">Production date</div>
                      <div x-text="formatDate(entry.date)"></div>
                    </div>
                    <div class="col-6">
                      <div class="text-body-secondary">Expiration</div>
                      <div x-text="expirationFor(entry).detail"></div>
                    </div>
                  </div>

                  <div class="quick-edit-stack">
                    <template x-if="entry.stock_type === 'binary'">
                      <div class="d-flex flex-wrap gap-2">
                        <button class="btn btn-sm btn-outline-danger" type="button" @click="updateBinary(entry, 'gone')">Mark gone</button>
                      </div>
                    </template>
                    <template x-if="entry.stock_type === 'descriptive'">
                      <div class="d-grid gap-2">
                        <select class="form-select form-select-sm" x-model="editForms[entry.id].level">
                          <template x-for="option in levelOptions" :key="option.value">
                            <option :value="option.value" x-text="option.label"></option>
                          </template>
                        </select>
                        <div class="d-flex flex-wrap gap-2">
                          <button class="btn btn-sm btn-primary" type="button" @click="saveLevel(entry)">Save stock level</button>
                          <button class="btn btn-sm btn-outline-danger" type="button" @click="markGone(entry)">Mark gone</button>
                        </div>
                      </div>
                    </template>
                    <template x-if="entry.stock_type === 'measured'">
                      <div class="d-grid gap-2">
                        <input class="form-control form-control-sm" type="number" step="0.01" min="0" x-model="editForms[entry.id].quantity" />
                        <div class="d-flex flex-wrap gap-2">
                          <button class="btn btn-sm btn-primary" type="button" @click="saveQuantity(entry)">Save quantity</button>
                          <button class="btn btn-sm btn-outline-danger" type="button" @click="markGone(entry)">Mark gone</button>
                        </div>
                      </div>
                    </template>
                    <template x-if="editErrors[entry.id]">
                      <div class="small text-danger mt-2" x-text="editErrors[entry.id]"></div>
                    </template>
                  </div>
                </div>
              </div>
            </template>
          </div>
        </div>
      </template>

      <template x-if="!state.isLoading && !state.error && viewMode === 'grouped' && !filteredGroupedEntries.length">
        <div class="card border-0 shadow-sm">
          <div class="card-body p-4 text-center">
            <h2 class="h5">No grouped stock items to show</h2>
            <p class="text-body-secondary mb-0">
              Try clearing the filters or create a new stock label.
            </p>
          </div>
        </div>
      </template>

      <template x-if="!state.isLoading && !state.error && viewMode === 'grouped' && filteredGroupedEntries.length">
        <div class="d-grid gap-3">
          <template x-for="group in visibleGroupedEntries" :key="group.id">
            <details
              class="card border-0 shadow-sm grouped-stock-card"
              :class="rowClass(group)"
              :data-group-id="String(group.id)"
              @toggle="handleGroupedToggle($event)"
            >
              <summary class="card-body p-3 grouped-stock-summary">
                <div class="d-flex flex-column flex-xl-row justify-content-between gap-2 grouped-stock-summary-row">
                  <div>
                    <div class="fw-semibold grouped-stock-summary-title" x-text="group.name"></div>
                    <div class="text-body-secondary small grouped-stock-summary-description" x-show="group.description" x-text="group.description"></div>
                    <div class="d-flex flex-wrap gap-3 small grouped-stock-summary-meta">
                      <span><span class="fw-semibold text-body" x-text="groupItemCount(group)"></span> item(s)</span>
                      <span><span class="text-body-secondary">Latest location:</span> <span class="fw-semibold text-body" x-text="locationLabel(group)"></span></span>
                      <span><span class="text-body-secondary">Latest quantity:</span> <span class="fw-semibold text-body" x-text="quantityLabel(group)"></span></span>
                    </div>
                  </div>
                  <div class="grouped-stock-summary-status">
                    <span class="badge rounded-pill" :class="badgeClass(group)" x-text="expirationFor(group).label"></span>
                    <div class="small text-body-secondary">
                      <span class="text-body-secondary">First expires:</span>
                      <span x-text="expirationFor(group).detail"></span>
                    </div>
                    <div class="small fw-semibold grouped-stock-toggle-label">Items</div>
                  </div>
                </div>
              </summary>
              <div class="card-body pt-0 px-4 pb-3">
                <div class="grouped-stock-secondary-details mb-3">
                  <details class="grouped-stock-secondary-toggle">
                    <summary class="small fw-semibold">More dates and metadata</summary>
                    <div class="row g-3 small mt-1 grouped-stock-meta">
                      <div class="col-6 col-xl-4">
                        <div class="text-body-secondary">Latest added</div>
                        <div x-text="formatDate(groupedPrimaryDate(group))"></div>
                      </div>
                      <div class="col-6 col-xl-4">
                        <div class="text-body-secondary">First production date</div>
                        <div x-text="formatDate(groupedFirstProductionDate(group))"></div>
                      </div>
                      <div class="col-6 col-xl-4">
                        <div class="text-body-secondary">First expiration date</div>
                        <div x-text="formatDate(groupedFirstExpireDate(group))"></div>
                      </div>
                    </div>
                  </details>
                </div>

                <template x-if="isGroupedCardOpen(group.id)">
                  <div>
                    <template x-if="group.items?.length">
                      <div class="grouped-stock-items">
                        <template x-for="item in group.items" :key="item.id">
                          <div class="grouped-stock-item" :class="groupedItemClass(item)">
                            <div class="grouped-stock-item-row">
                              <div class="grouped-stock-item-main">
                                <div class="grouped-stock-item-title-line">
                                  <div class="fw-semibold grouped-stock-item-name" x-text="item.name"></div>
                                  <span class="font-monospace grouped-stock-item-id" x-text="shortId(item)"></span>
                                </div>
                                <div class="small text-body-secondary grouped-stock-item-subline">
                                  <span x-text="locationLabel(item)"></span>
                                  <span class="grouped-stock-subline-separator" aria-hidden="true">•</span>
                                  <span x-text="shortDescription(item.description)"></span>
                                </div>
                              </div>
                              <div class="small text-body-secondary grouped-stock-item-aux">
                                <span x-text="quantityLabel(item)"></span>
                                <span class="grouped-stock-date-pair">
                                  <span x-text="formatDate(item.date)"></span>
                                  <span class="grouped-stock-date-separator" aria-hidden="true">→</span>
                                  <span x-text="formatDate(item.expire_date)"></span>
                                </span>
                              </div>
                              <div class="grouped-stock-item-actions">
                                <a class="text-decoration-none fw-semibold grouped-stock-item-link" :href="detailHref(item)">Details</a>
                                <button class="btn btn-sm btn-outline-danger grouped-stock-mark-gone" type="button" @click="markGoneFromGroup(item, group)">Mark gone</button>
                              </div>
                            </div>
                            <template x-if="editErrors[item.id]">
                              <div class="small text-danger mt-2" x-text="editErrors[item.id]"></div>
                            </template>
                          </div>
                        </template>
                      </div>
                    </template>
                    <template x-if="!group.items?.length && groupedHydrating">
                      <div class="small text-body-secondary py-2">Loading grouped items...</div>
                    </template>
                    <template x-if="!group.items?.length && !groupedHydrating">
                      <div class="small text-body-secondary py-2">No items currently available in this group.</div>
                    </template>
                  </div>
                </template>

                <div class="grouped-stock-close-row">
                  <button
                    class="btn btn-link text-decoration-none grouped-stock-close"
                    type="button"
                    @click.prevent="closeGroupedCard($el.closest('details'))"
                  >
                    Collapse group
                  </button>
                </div>
              </div>
            </details>
          </template>
          <template x-if="hasMoreGroupedEntries">
            <div class="d-flex justify-content-center">
              <button class="btn btn-outline-secondary" type="button" @click="showMoreGroups()">
                Show more groups
              </button>
            </div>
          </template>
        </div>
      </template>
        </div>
      </div>
    </section>
  `;
}

export function stockListPageData(store) {
  return {
    state: {
      ...createAsyncState(),
      isRefreshing: false,
    },
    viewMode: 'grouped',
    entries: [],
    entriesVersion: 0,
    itemsLoaded: false,
    groupedEntries: [],
    groupedVersion: 0,
    groupedLoaded: false,
    groupedHydrated: false,
    groupedHydrating: false,
    groupedPageSize: GROUPED_PAGE_SIZE,
    groupedVisibleLimit: GROUPED_PAGE_SIZE,
    openGroupedCards: {},
    refreshActivityCount: 0,
    locations: [],
    locationsVersion: 0,
    locationMap: {},
    locationDescendants: {},
    locationLineage: {},
    editForms: {},
    editErrors: {},
    levelOptions: LEVEL_OPTIONS,
    expirationLegend: EXPIRATION_LEGEND,
    overviewOpen: {
      expiration: false,
      location: false,
    },
    filters: {
      search: '',
      expiration: [],
      location: [],
    },
    memo: {
      filteredEntriesSig: '',
      filteredEntries: [],
      filteredGroupedEntriesSig: '',
      filteredGroupedEntries: [],
      expirationCountsSig: '',
      expirationCounts: {},
      locationCountsSig: '',
      locationCounts: {},
    },
    changeCursor: null,
    changePollTimer: null,
    routeChangeHandler: null,
    isPollingChanges: false,
    async init() {
      if (!store.isConnected) {
        return;
      }

      this.registerRouteCleanup();
      await Promise.all([
        this.loadLocations(),
        this.loadGroupedEntries({ expanded: 0, resetVisible: true }),
      ]);

      await this.$nextTick();
      this.hydrateGroupedEntriesInBackground().catch(() => {});
      await this.primeChangeCursor();
      this.startChangePolling();
    },
    registerRouteCleanup() {
      if (this.routeChangeHandler) {
        return;
      }

      this.routeChangeHandler = () => {
        if (!this.isStockListRoute()) {
          this.stopChangePolling();
          window.removeEventListener('hashchange', this.routeChangeHandler);
          this.routeChangeHandler = null;
        }
      };

      window.addEventListener('hashchange', this.routeChangeHandler);
    },
    isStockListRoute() {
      const route = (window.location.hash || '#/').replace(/^#/, '') || '/';
      return route === '/stock';
    },
    async primeChangeCursor() {
      try {
        const payload = await listKitchenChanges(store, { limit: 1 });
        this.changeCursor = payload.nextCursor || payload.since || this.changeCursor;
      } catch {
        this.changeCursor = this.changeCursor || null;
      }
    },
    startChangePolling() {
      if (this.changePollTimer) {
        return;
      }

      this.changePollTimer = window.setInterval(() => {
        this.pollKitchenChanges().catch(() => {});
      }, CHANGE_POLL_INTERVAL_MS);
    },
    stopChangePolling() {
      if (this.changePollTimer) {
        window.clearInterval(this.changePollTimer);
        this.changePollTimer = null;
      }
    },
    async pollKitchenChanges() {
      if (this.isPollingChanges || !store.isConnected || !this.isStockListRoute()) {
        return;
      }

      this.isPollingChanges = true;

      try {
        const payload = await listKitchenChanges(store, {
          since: this.changeCursor || undefined,
          limit: 25,
        });
        this.changeCursor = payload.nextCursor || payload.since || this.changeCursor;

        if (!payload.changes.length) {
          return;
        }

        await this.refreshCurrentView({ background: true });
      } finally {
        this.isPollingChanges = false;
      }
    },
    showInitialLoader() {
      if (!this.state.isLoading) {
        return false;
      }

      return this.viewMode === 'grouped' ? !this.groupedLoaded : !this.itemsLoaded;
    },
    beginBackgroundRefresh() {
      this.refreshActivityCount += 1;
      this.state.isRefreshing = true;
    },
    endBackgroundRefresh() {
      this.refreshActivityCount = Math.max(0, this.refreshActivityCount - 1);
      this.state.isRefreshing = this.refreshActivityCount > 0;
    },
    invalidateMemo() {
      this.memo.filteredEntriesSig = '';
      this.memo.filteredGroupedEntriesSig = '';
      this.memo.expirationCountsSig = '';
      this.memo.locationCountsSig = '';
    },
    indexEntry(entry) {
      const indexed = { ...entry };
      indexed._searchBlob = searchBlob(indexed, this.locationMap);
      return indexed;
    },
    indexGroup(group) {
      const indexedItems = Array.isArray(group.items)
        ? group.items.map((item) => this.indexEntry(item))
        : [];
      const indexed = {
        ...group,
        items: indexedItems,
      };
      indexed._searchBlob = groupSearchBlob(indexed, this.locationMap);
      return indexed;
    },
    reindexSearchData() {
      if (this.entries.length) {
        this.entries = this.entries.map((entry) => this.indexEntry(entry));
        this.entriesVersion += 1;
      }
      if (this.groupedEntries.length) {
        this.groupedEntries = this.groupedEntries.map((group) => this.indexGroup(group));
        this.groupedVersion += 1;
      }
      this.invalidateMemo();
    },
    syncEditFormsFromEntries() {
      this.editForms = Object.fromEntries(
        this.entries.map((entry) => [
          entry.id,
          {
            level: entry.level || 'plenty',
            quantity: entry.quantity ?? '',
          },
        ]),
      );
      this.editErrors = {};
    },
    async switchView(mode) {
      this.viewMode = mode;

      if (mode === 'grouped') {
        if (!this.groupedLoaded) {
          await this.loadGroupedEntries({ expanded: 0, resetVisible: true });
        }
        this.hydrateGroupedEntriesInBackground().catch(() => {});
        return;
      }

      if (!this.itemsLoaded) {
        await this.loadEntries();
      }
    },
    async refreshCurrentView({ background = false } = {}) {
      const useBackground = background || (this.viewMode === 'grouped'
        ? this.groupedLoaded
        : this.itemsLoaded);

      if (this.viewMode === 'grouped') {
        await this.loadGroupedEntries({ expanded: 0, background: useBackground });
        this.hydrateGroupedEntriesInBackground({ force: true }).catch(() => {});
        return;
      }

      await this.loadEntries({ background: useBackground });
    },
    async loadEntries({ background = false } = {}) {
      if (!store.isConnected) {
        return;
      }

      const shouldBlock = !background && !this.itemsLoaded;
      if (background) {
        this.beginBackgroundRefresh();
      } else if (shouldBlock) {
        this.state.isLoading = true;
        this.state.error = '';
      }

      try {
        const loadedEntries = await listStockEntries(store);
        this.entries = sortEntries(loadedEntries.map((entry) => this.indexEntry(entry)));
        this.itemsLoaded = true;
        this.entriesVersion += 1;
        this.syncEditFormsFromEntries();
        this.invalidateMemo();
      } catch (error) {
        if (!background) {
          this.state.error = error.message || 'Could not load stock items.';
        }
      } finally {
        if (background) {
          this.endBackgroundRefresh();
        } else if (shouldBlock) {
          this.state.isLoading = false;
        }
      }
    },
    applyGroupedSummary(loadedGroups, { resetVisible = false } = {}) {
      const existingById = new Map(this.groupedEntries.map((group) => [group.id, group]));
      const nextGroups = loadedGroups.map((group) => {
        const existing = existingById.get(group.id);
        const preservedItems = Array.isArray(group.items) ? group.items : existing?.items || [];
        return this.indexGroup({
          ...existing,
          ...group,
          items: preservedItems,
        });
      });

      this.groupedEntries = sortGroupedEntries(nextGroups);
      this.groupedLoaded = true;
      this.groupedHydrated = false;
      this.groupedVersion += 1;
      this.pruneOpenGroupedCards();
      this.invalidateMemo();

      if (resetVisible) {
        this.resetGroupedVisibleLimit();
      }
    },
    applyGroupedHydration(loadedGroups) {
      const existingById = new Map(this.groupedEntries.map((group) => [group.id, group]));
      const nextGroups = loadedGroups.map((group) => {
        const existing = existingById.get(group.id);
        const mergedItems = Array.isArray(group.items) ? group.items : existing?.items || [];
        return this.indexGroup({
          ...existing,
          ...group,
          items: mergedItems,
        });
      });

      this.groupedEntries = sortGroupedEntries(nextGroups);
      this.groupedLoaded = true;
      this.groupedHydrated = true;
      this.groupedVersion += 1;
      this.pruneOpenGroupedCards();
      this.invalidateMemo();
    },
    async loadGroupedEntries({ expanded = 1, background = false, resetVisible = false } = {}) {
      if (!store.isConnected) {
        return;
      }

      const shouldBlock = !background && !this.groupedLoaded;
      if (background) {
        this.beginBackgroundRefresh();
      } else if (shouldBlock) {
        this.state.isLoading = true;
        this.state.error = '';
      }

      try {
        const loadedGroups = await listGroupedStockEntries(store, { expanded });
        if (expanded === 0) {
          this.applyGroupedSummary(loadedGroups, { resetVisible });
          return;
        }

        this.applyGroupedHydration(loadedGroups);
      } catch (error) {
        if (!background) {
          this.state.error = error.message || 'Could not load grouped stock.';
        }
      } finally {
        if (background) {
          this.endBackgroundRefresh();
        } else if (shouldBlock) {
          this.state.isLoading = false;
        }
      }
    },
    async hydrateGroupedEntriesInBackground({ force = false } = {}) {
      if (!this.groupedLoaded || this.groupedHydrating) {
        return;
      }

      if (this.groupedHydrated && !force) {
        return;
      }

      this.groupedHydrating = true;
      try {
        await this.loadGroupedEntries({ expanded: 1, background: true });
      } finally {
        this.groupedHydrating = false;
      }
    },
    async refreshLoadedViewsInBackground() {
      const tasks = [];
      if (this.itemsLoaded) {
        tasks.push(this.loadEntries({ background: true }));
      }
      if (this.groupedLoaded) {
        tasks.push(
          this.loadGroupedEntries({ expanded: 0, background: true }).then(() =>
            this.hydrateGroupedEntriesInBackground({ force: true }),
          ),
        );
      }
      await Promise.allSettled(tasks);
    },
    async loadLocations() {
      if (!store.isConnected) {
        return;
      }

      try {
        const { flat } = await fetchLocations(store);
        this.locations = flat;
        this.locationMap = Object.fromEntries(
          flat.map((location) => [location.uuid_b64, location.pathLabel]),
        );
        this.locationLineage = Object.fromEntries(
          flat.map((location) => [location.uuid_b64, location.lineage_uuid_b64 || []]),
        );
        this.locationDescendants = Object.fromEntries(
          flat.map((location) => [
            location.uuid_b64,
            flat
              .filter((candidate) => candidate.lineage_uuid_b64.includes(location.uuid_b64))
              .map((candidate) => candidate.uuid_b64),
          ]),
        );
      } catch {
        this.locations = [];
        this.locationMap = {};
        this.locationLineage = {};
        this.locationDescendants = {};
      } finally {
        this.locationsVersion += 1;
        this.reindexSearchData();
      }
    },
    resetGroupedVisibleLimit() {
      this.groupedVisibleLimit = this.groupedPageSize;
    },
    showMoreGroups() {
      this.groupedVisibleLimit += this.groupedPageSize;
    },
    groupItemCount(group) {
      if (Number.isFinite(group.items_count)) {
        return group.items_count;
      }
      if (Number.isFinite(group.count)) {
        return group.count;
      }
      return Array.isArray(group.items) ? group.items.length : 0;
    },
    isGroupedCardOpen(groupId) {
      return Boolean(this.openGroupedCards[String(groupId)]);
    },
    pruneOpenGroupedCards() {
      const activeIds = new Set(this.groupedEntries.map((group) => String(group.id)));
      this.openGroupedCards = Object.fromEntries(
        Object.entries(this.openGroupedCards).filter(
          ([groupId, isOpen]) => isOpen && activeIds.has(groupId),
        ),
      );
    },
    clearFilters() {
      this.filters = {
        search: '',
        expiration: [],
        location: [],
      };
      this.resetGroupedVisibleLimit();
    },
    setOverviewOpen(key, open) {
      this.overviewOpen[key] = open;

      if (!open || !this.isCompactOverviewLayout()) {
        return;
      }

      const otherKey = key === 'expiration' ? 'location' : 'expiration';
      this.overviewOpen[otherKey] = false;

      const otherPanel =
        otherKey === 'expiration'
          ? this.$refs.expirationOverview
          : this.$refs.locationOverview;

      if (otherPanel?.open) {
        otherPanel.open = false;
      }
    },
    isCompactOverviewLayout() {
      return window.matchMedia('(max-width: 1199.98px)').matches;
    },
    openOverviewCount() {
      return Number(this.overviewOpen.expiration) + Number(this.overviewOpen.location);
    },
    isOnlyOverviewOpen(key) {
      return this.openOverviewCount() === 1 && this.overviewOpen[key];
    },
    overviewRowClass() {
      return this.openOverviewCount() === 1 ? 'overview-row-single-open' : '';
    },
    overviewColClass(key) {
      if (this.openOverviewCount() === 1) {
        return 'col-xl-12';
      }

      return key === 'expiration' ? 'col-xl-5' : 'col-xl-7';
    },
    isAllExpirationSelected() {
      return (
        this.filters.expiration.length === 0
        || this.filters.expiration.length === EXPIRATION_KEYS.length
      );
    },
    effectiveExpirationFilters() {
      if (this.isAllExpirationSelected()) {
        return [];
      }
      return [...new Set(this.filters.expiration)];
    },
    effectiveLocationFilters() {
      const unique = [...new Set(this.filters.location)];
      if (unique.length === 0 || (this.locations.length > 0 && unique.length === this.locations.length)) {
        return [];
      }
      return unique;
    },
    expirationFilterSummary() {
      const active = this.effectiveExpirationFilters();
      if (!active.length) {
        return 'All states';
      }

      if (active.length === 1) {
        return this.expirationLegend.find((state) => state.key === active[0])?.label || '1 state';
      }

      return `${active.length} states selected`;
    },
    locationFilterSummary() {
      const active = this.effectiveLocationFilters();
      if (!active.length) {
        return 'All locations';
      }

      if (active.length === 1) {
        return this.locationMap[active[0]] || '1 location selected';
      }

      return `${active.length} locations selected`;
    },
    normalizedSearchTerm() {
      return String(this.filters.search || '').trim().toLowerCase();
    },
    toggleAllExpirationFilters() {
      this.filters.expiration = [];
      this.resetGroupedVisibleLimit();
    },
    toggleExpirationOverviewFilter(key) {
      if (this.isAllExpirationSelected()) {
        this.filters.expiration = [key];
        this.resetGroupedVisibleLimit();
        return;
      }

      this.toggleExpirationFilter(key);
    },
    toggleExpirationFilter(key) {
      if (this.filters.expiration.includes(key)) {
        this.filters.expiration = this.filters.expiration.filter((value) => value !== key);
      } else {
        this.filters.expiration = [...this.filters.expiration, key];
      }
      this.resetGroupedVisibleLimit();
    },
    isAllLocationsSelected() {
      return (
        this.filters.location.length === 0
        || (this.locations.length > 0 && this.filters.location.length === this.locations.length)
      );
    },
    toggleAllLocations() {
      this.filters.location = [];
      this.resetGroupedVisibleLimit();
    },
    toggleLocationFilter(uuid) {
      const subtree = this.locationSubtree(uuid);

      if (this.filters.location.includes(uuid)) {
        this.filters.location = this.filters.location.filter((value) => !subtree.includes(value));
      } else {
        this.filters.location = [...new Set([...this.filters.location, ...subtree])];
      }
      this.resetGroupedVisibleLimit();
    },
    selectedLocationSummary() {
      if (this.isAllLocationsSelected()) {
        return '';
      }
      return `${this.filters.location.length} selected`;
    },
    locationOverviewGroups() {
      return this.locations
        .filter((location) => location.depth === 0)
        .map((parent) => ({
          parent,
          items: this.locations.filter(
            (location) => location.lineage_uuid_b64[0] === parent.uuid_b64,
          ),
        }));
    },
    balancedLocationOverviewColumns() {
      const columns = [[], []];
      const sizes = [0, 0];

      this.locationOverviewGroups().forEach((group) => {
        const groupSize = group.items.length;
        const targetIndex = sizes[0] <= sizes[1] ? 0 : 1;
        columns[targetIndex].push(group);
        sizes[targetIndex] += groupSize;
      });

      return columns;
    },
    get filteredEntries() {
      const searchTerm = this.normalizedSearchTerm();
      const expirationFilters = this.effectiveExpirationFilters().slice().sort().join(',');
      const locationFilters = this.effectiveLocationFilters().slice().sort().join(',');
      const signature = [
        this.entriesVersion,
        this.locationsVersion,
        searchTerm,
        expirationFilters,
        locationFilters,
      ].join('|');

      if (this.memo.filteredEntriesSig === signature) {
        return this.memo.filteredEntries;
      }

      const activeExpirationFilters = this.effectiveExpirationFilters();
      const activeLocationFilters = this.effectiveLocationFilters();
      const filtered = this.entries.filter((entry) => {
        if (searchTerm && !(entry._searchBlob || '').includes(searchTerm)) {
          return false;
        }
        if (
          activeExpirationFilters.length
          && !activeExpirationFilters.includes(expirationInfo(entry).key)
        ) {
          return false;
        }
        if (
          activeLocationFilters.length
          && !this.locationMatchesAnyFilter(entry.location_initial_uuid_b64, activeLocationFilters)
        ) {
          return false;
        }
        return true;
      });

      this.memo.filteredEntriesSig = signature;
      this.memo.filteredEntries = filtered;
      return filtered;
    },
    get filteredGroupedEntries() {
      const searchTerm = this.normalizedSearchTerm();
      const expirationFilters = this.effectiveExpirationFilters().slice().sort().join(',');
      const locationFilters = this.effectiveLocationFilters().slice().sort().join(',');
      const signature = [
        this.groupedVersion,
        this.locationsVersion,
        searchTerm,
        expirationFilters,
        locationFilters,
      ].join('|');

      if (this.memo.filteredGroupedEntriesSig === signature) {
        return this.memo.filteredGroupedEntries;
      }

      const activeExpirationFilters = this.effectiveExpirationFilters();
      const activeLocationFilters = this.effectiveLocationFilters();
      const filtered = this.groupedEntries.filter((group) => {
        if (searchTerm && !(group._searchBlob || '').includes(searchTerm)) {
          return false;
        }
        if (
          activeExpirationFilters.length
          && !activeExpirationFilters.includes(expirationInfo(group).key)
        ) {
          return false;
        }
        if (
          activeLocationFilters.length
          && !this.groupMatchesLocationFilters(group, activeLocationFilters)
        ) {
          return false;
        }
        return true;
      });

      this.memo.filteredGroupedEntriesSig = signature;
      this.memo.filteredGroupedEntries = filtered;
      return filtered;
    },
    get visibleGroupedEntries() {
      return this.filteredGroupedEntries.slice(0, this.groupedVisibleLimit);
    },
    get hasMoreGroupedEntries() {
      return this.filteredGroupedEntries.length > this.visibleGroupedEntries.length;
    },
    get visibleResultCount() {
      return this.viewMode === 'grouped'
        ? this.filteredGroupedEntries.length
        : this.filteredEntries.length;
    },
    expirationFor(entry) {
      return expirationInfo(entry);
    },
    isExpirationFilterActive(key) {
      return this.isAllExpirationSelected() || this.filters.expiration.includes(key);
    },
    rowClass(entry) {
      return `expiration-${expirationInfo(entry).key}`;
    },
    badgeClass(entry) {
      return `expiration-badge-${expirationInfo(entry).key}`;
    },
    groupedItemClass(entry) {
      return `expiration-soft-${expirationInfo(entry).key}`;
    },
    legendClass(key) {
      const hasActiveFilters = !this.isAllExpirationSelected();
      return [
        `legend-${key}`,
        hasActiveFilters && this.isExpirationFilterActive(key) ? 'legend-card-active' : '',
        hasActiveFilters && !this.isExpirationFilterActive(key) ? 'legend-card-inactive' : '',
      ]
        .filter(Boolean)
        .join(' ');
    },
    getExpirationCounts() {
      const searchTerm = this.normalizedSearchTerm();
      const locationFilters = this.effectiveLocationFilters().slice().sort().join(',');
      const sourceVersion = this.viewMode === 'grouped' ? this.groupedVersion : this.entriesVersion;
      const signature = [
        this.viewMode,
        sourceVersion,
        this.locationsVersion,
        searchTerm,
        locationFilters,
      ].join('|');

      if (this.memo.expirationCountsSig === signature) {
        return this.memo.expirationCounts;
      }

      const counts = Object.fromEntries(EXPIRATION_KEYS.map((key) => [key, 0]));
      const activeLocationFilters = this.effectiveLocationFilters();
      const source = this.viewMode === 'grouped' ? this.groupedEntries : this.entries;
      source.forEach((entry) => {
        const blob = entry._searchBlob || '';
        if (searchTerm && !blob.includes(searchTerm)) {
          return;
        }

        const matchesLocation = this.viewMode === 'grouped'
          ? this.groupMatchesLocationFilters(entry, activeLocationFilters)
          : this.locationMatchesAnyFilter(entry.location_initial_uuid_b64, activeLocationFilters);
        if (!matchesLocation) {
          return;
        }

        const key = expirationInfo(entry).key;
        counts[key] += 1;
      });

      this.memo.expirationCountsSig = signature;
      this.memo.expirationCounts = counts;
      return counts;
    },
    expirationCount(key) {
      return this.getExpirationCounts()[key] || 0;
    },
    shortId(entry) {
      return entry.uuid_b64 ? entry.uuid_b64.slice(0, 10) : 'No id';
    },
    locationLabel(entry) {
      return resolveLocationLabel(entry, this.locationMap);
    },
    isLocationFilterActive(uuid) {
      return this.isAllLocationsSelected() || this.filters.location.includes(uuid);
    },
    toggleLocationOverviewFilter(uuid) {
      if (this.isAllLocationsSelected()) {
        this.filters.location = [...this.locationSubtree(uuid)];
        this.resetGroupedVisibleLimit();
        return;
      }

      this.toggleLocationFilter(uuid);
    },
    locationOverviewClass(location) {
      const hasActiveFilters = !this.isAllLocationsSelected();
      return [
        'location-overview',
        `location-type-${location.type || 'unknown'}`,
        location.depth ? 'location-overview-child' : 'location-overview-parent',
        hasActiveFilters && this.isLocationFilterActive(location.uuid_b64) ? 'legend-card-active' : '',
        hasActiveFilters && !this.isLocationFilterActive(location.uuid_b64) ? 'legend-card-inactive' : '',
      ]
        .filter(Boolean)
        .join(' ');
    },
    locationOverviewStyle(location) {
      const offset = location.depth;
      return `margin-left: ${offset}rem; width: calc(100% - ${offset}rem);`;
    },
    locationAncestors(locationUuid) {
      if (!locationUuid) {
        return [];
      }

      return this.locationLineage[locationUuid] || [locationUuid];
    },
    groupLocationAncestors(group) {
      const allLocations = new Set();
      if (group.location_initial_uuid_b64) {
        allLocations.add(group.location_initial_uuid_b64);
      }
      (group.items || []).forEach((item) => {
        if (item.location_initial_uuid_b64) {
          allLocations.add(item.location_initial_uuid_b64);
        }
      });

      const ancestors = new Set();
      allLocations.forEach((locationUuid) => {
        this.locationAncestors(locationUuid).forEach((ancestor) => ancestors.add(ancestor));
      });
      return [...ancestors];
    },
    getLocationCounts() {
      const searchTerm = this.normalizedSearchTerm();
      const expirationFilters = this.effectiveExpirationFilters().slice().sort().join(',');
      const sourceVersion = this.viewMode === 'grouped' ? this.groupedVersion : this.entriesVersion;
      const signature = [
        this.viewMode,
        sourceVersion,
        this.locationsVersion,
        searchTerm,
        expirationFilters,
      ].join('|');

      if (this.memo.locationCountsSig === signature) {
        return this.memo.locationCounts;
      }

      const counts = Object.fromEntries(this.locations.map((location) => [location.uuid_b64, 0]));
      const activeExpirationFilters = this.effectiveExpirationFilters();
      const source = this.viewMode === 'grouped' ? this.groupedEntries : this.entries;

      source.forEach((entry) => {
        const blob = entry._searchBlob || '';
        if (searchTerm && !blob.includes(searchTerm)) {
          return;
        }
        if (
          activeExpirationFilters.length
          && !activeExpirationFilters.includes(expirationInfo(entry).key)
        ) {
          return;
        }

        const ancestors = this.viewMode === 'grouped'
          ? this.groupLocationAncestors(entry)
          : this.locationAncestors(entry.location_initial_uuid_b64);
        ancestors.forEach((ancestorUuid) => {
          if (counts[ancestorUuid] !== undefined) {
            counts[ancestorUuid] += 1;
          }
        });
      });

      this.memo.locationCountsSig = signature;
      this.memo.locationCounts = counts;
      return counts;
    },
    locationCount(locationUuid) {
      return this.getLocationCounts()[locationUuid] || 0;
    },
    locationMatchesFilter(entryLocationUuid, selectedLocationUuid) {
      if (!selectedLocationUuid) {
        return true;
      }

      const allowed = this.locationDescendants[selectedLocationUuid] || [selectedLocationUuid];
      return allowed.includes(entryLocationUuid);
    },
    locationSubtree(selectedLocationUuid) {
      return this.locationDescendants[selectedLocationUuid] || [selectedLocationUuid];
    },
    locationMatchesAnyFilter(entryLocationUuid, selectedLocationUuids) {
      if (!selectedLocationUuids.length) {
        return true;
      }

      return selectedLocationUuids.some((selectedLocationUuid) =>
        this.locationMatchesFilter(entryLocationUuid, selectedLocationUuid),
      );
    },
    groupMatchesLocationFilter(group, selectedLocationUuid) {
      if (!selectedLocationUuid) {
        return true;
      }

      if (this.locationMatchesFilter(group.location_initial_uuid_b64, selectedLocationUuid)) {
        return true;
      }

      return (group.items || []).some((item) =>
        this.locationMatchesFilter(item.location_initial_uuid_b64, selectedLocationUuid),
      );
    },
    groupMatchesLocationFilters(group, selectedLocationUuids) {
      if (!selectedLocationUuids.length) {
        return true;
      }

      return selectedLocationUuids.some((selectedLocationUuid) =>
        this.groupMatchesLocationFilter(group, selectedLocationUuid),
      );
    },
    detailHref(entry) {
      return `#/stock/${entry.uuid_b64}`;
    },
    closeGroupedCard(details) {
      if (!details) {
        return;
      }

      details.open = false;
      if (details.dataset?.groupId) {
        this.openGroupedCards = {
          ...this.openGroupedCards,
          [String(details.dataset.groupId)]: false,
        };
      }
    },
    handleGroupedToggle(event) {
      const details = event.target;
      if (!(details instanceof HTMLDetailsElement)) {
        return;
      }

      if (details.dataset?.groupId) {
        this.openGroupedCards = {
          ...this.openGroupedCards,
          [String(details.dataset.groupId)]: details.open,
        };
      }

      if (details.open) {
        return;
      }

      const summary = details.querySelector('.grouped-stock-summary');
      if (!summary) {
        return;
      }

      requestAnimationFrame(() => {
        summary.scrollIntoView({
          block: 'start',
          behavior: 'smooth',
        });
      });
    },
    groupedPrimaryDate,
    groupedFirstProductionDate,
    groupedFirstExpireDate,
    shortDescription,
    quantityLabel,
    stockTypeDetail(entry) {
      if (entry.stock_type === 'binary') {
        return 'Binary stock';
      }
      if (entry.stock_type === 'descriptive') {
        return `Level: ${LEVEL_LABELS[entry.level] || 'Not set'}`;
      }
      return entry.uom_symbol ? `Measured in ${entry.uom_symbol}` : 'Measured stock';
    },
    formatDate,
    async updateBinary(entry) {
      await this.useEntry(entry);
    },
    async saveLevel(entry) {
      const level = this.editForms[entry.id]?.level || 'plenty';
      if (level === 'gone') {
        await this.useEntry(entry);
        return;
      }

      await this.saveEntryUpdate(
        entry,
        {
          level,
        },
        { level },
      );
    },
    async saveQuantity(entry) {
      const quantity = Number(this.editForms[entry.id]?.quantity);
      if (Number.isNaN(quantity) || quantity < 0) {
        this.editErrors[entry.id] = 'Enter a valid quantity first.';
        return;
      }

      await this.saveEntryUpdate(
        entry,
        {
          quantity,
        },
        { quantity },
      );
    },
    async markGone(entry) {
      await this.useEntry(entry);
    },
    async markGoneFromGroup(item, group) {
      this.editErrors[item.id] = '';

      try {
        const result = await useStockItem(store, item.uuid_b64);
        const alreadyGone = result.status === 'already_gone';
        this.removeGroupedItem(group.id, item.id);
        this.removeEntryLocally(item.id);
        delete this.editForms[item.id];
        delete this.editErrors[item.id];
        store.addAlert({
          type: alreadyGone ? 'info' : 'success',
          message: alreadyGone
            ? `${item.name} was already out of stock and removed from the group.`
            : `${item.name} was marked gone and removed from the group.`,
        });
        this.refreshLoadedViewsInBackground().catch(() => {});
      } catch (error) {
        this.editErrors[item.id] = error.message || 'Mark gone failed.';
      }
    },
    async saveEntryUpdate(entry, payload, localPatch) {
      this.editErrors[entry.id] = '';

      try {
        const updated = await updateStockItem(store, entry.uuid_b64, payload);
        this.replaceEntry(entry.id, { ...entry, ...localPatch, ...updated });
        store.addAlert({
          type: 'success',
          message: `${entry.name} updated successfully.`,
        });
        this.refreshLoadedViewsInBackground().catch(() => {});
      } catch (error) {
        this.editErrors[entry.id] = error.message || 'Update failed.';
      }
    },
    async useEntry(entry) {
      this.editErrors[entry.id] = '';

      try {
        const result = await useStockItem(store, entry.uuid_b64);
        const alreadyGone = result.status === 'already_gone';
        this.removeEntryLocally(entry.id);
        delete this.editForms[entry.id];
        delete this.editErrors[entry.id];
        store.addAlert({
          type: alreadyGone ? 'info' : 'success',
          message: alreadyGone
            ? `${entry.name} was already out of stock and removed from the list.`
            : `${entry.name} was marked gone and removed from the list.`,
        });
        this.refreshLoadedViewsInBackground().catch(() => {});
      } catch (error) {
        this.editErrors[entry.id] = error.message || 'Mark gone failed.';
      }
    },
    removeEntryLocally(entryId) {
      if (!this.entries.length) {
        return;
      }

      this.entries = this.entries.filter((entry) => entry.id !== entryId);
      this.entriesVersion += 1;
      this.invalidateMemo();
    },
    replaceEntry(entryId, nextEntry) {
      this.entries = sortEntries(
        this.entries.map((entry) =>
          entry.id === entryId ? this.indexEntry(nextEntry) : entry,
        ),
      );
      this.entriesVersion += 1;
      this.invalidateMemo();
      this.editForms[entryId] = {
        level: nextEntry.level || 'plenty',
        quantity: nextEntry.quantity ?? '',
      };
    },
    removeGroupedItem(groupId, itemId) {
      this.groupedEntries = sortGroupedEntries(
        this.groupedEntries
          .map((group) => {
            if (group.id !== groupId) {
              return group;
            }

            const nextItems = (group.items || []).filter((candidate) => candidate.id !== itemId);
            if (!nextItems.length) {
              return null;
            }

            return this.indexGroup({
              ...group,
              items: nextItems,
            });
          })
          .filter(Boolean),
      );
      this.groupedVersion += 1;
      this.pruneOpenGroupedCards();
      this.invalidateMemo();
    },
  };
}