import { fetchLocations } from '../../api/locations.js';
import { getStockEntry, listKitchenChanges } from '../../api/stock.js';
import { createAsyncState, runAsyncState } from '../shared/ui-state.js';

export function renderDashboardPage() {
  return `
    <section class="container-xxl py-4 py-lg-5" x-data="dashboardPage()" x-init="init()">
      <div class="hero-card p-4 p-lg-5 mb-4">
        <div class="row align-items-center g-4">
          <div class="col-12 col-lg-7">
            <p class="eyebrow mb-2">Kitchen stock management</p>
            <h1 class="display-6 mb-3">Keep labels, stock, and adjustments in one focused workflow.</h1>
            <p class="lead text-body-secondary mb-4">
              This MVP is shaped for fast household operations on a phone or desktop, with the Tryton backend staying in charge of business logic.
            </p>
            <div class="d-flex flex-wrap gap-2">
              <a href="#/labels/new" class="btn btn-primary btn-lg">Create label</a>
              <a href="#/scan" class="btn btn-outline-primary btn-lg">Scan item</a>
              <a href="#/stock" class="btn btn-outline-primary btn-lg">Browse stock</a>
            </div>
          </div>
          <div class="col-12 col-lg-5">
            <div class="glass-panel p-4">
              <div class="small text-uppercase text-body-secondary mb-2">Active kitchen</div>
              <div class="h4 mb-2" x-text="$store.app.activeKitchen?.name || 'Select a kitchen'"></div>
              <div class="text-body-secondary mb-3">
                Switch without signing out when you need to work across kitchens in the same Tryton database.
              </div>
              <button class="btn btn-outline-secondary" @click="showKitchenPicker = !showKitchenPicker">Switch kitchen</button>
            </div>
          </div>
        </div>
      </div>

      <template x-if="showKitchenPicker">
        <div class="mb-4">
          <div class="card border-0 shadow-sm">
            <div class="card-body p-4">
              <div class="d-flex justify-content-between align-items-center mb-3">
                <h2 class="h5 mb-0">Choose kitchen</h2>
                <button class="btn btn-sm btn-outline-secondary" @click="showKitchenPicker = false">Close</button>
              </div>
              <div class="row g-3">
                <template x-for="kitchen in $store.app.kitchens" :key="kitchen.id">
                  <div class="col-12 col-md-6 col-xl-4">
                    <button class="btn kitchen-card w-100 text-start" @click="setKitchen(kitchen)">
                      <div class="fw-semibold" x-text="kitchen.name"></div>
                      <div class="small text-body-secondary" x-text="kitchen.description || 'Kitchen workspace'"></div>
                    </button>
                  </div>
                </template>
              </div>
            </div>
          </div>
        </div>
      </template>

      <div class="row g-4">
        <div class="col-12 col-md-6 col-xl-3">
          <a class="quick-card" href="#/labels/new">
            <span class="quick-card-label">Labels</span>
            <strong>New label & stock entry</strong>
            <span class="text-body-secondary">Search an item, fill the batch fields, preview, then create.</span>
          </a>
        </div>
        <div class="col-12 col-md-6 col-xl-3">
          <a class="quick-card" href="#/stock">
            <span class="quick-card-label">Stock</span>
            <strong>Overview & filters</strong>
            <span class="text-body-secondary">Browse current entries with mobile-friendly cards and table view.</span>
          </a>
        </div>
        <div class="col-12 col-md-6 col-xl-3">
          <a class="quick-card" href="#/scan">
            <span class="quick-card-label">Scanning</span>
            <strong>Use, spoil, or inspect</strong>
            <span class="text-body-secondary">Scan a label or barcode and act on the matching item.</span>
          </a>
        </div>
        <div class="col-12 col-md-6 col-xl-3">
          <a class="quick-card" href="#/settings">
            <span class="quick-card-label">Settings</span>
            <strong>Connection details</strong>
            <span class="text-body-secondary">Update the Tryton base URL and database without leaving the app.</span>
          </a>
        </div>
      </div>

      <div class="row g-4 mt-1">
        <div class="col-12">
          <div class="card border-0 shadow-sm">
            <div class="card-body p-4">
              <div class="d-flex flex-wrap justify-content-between align-items-center gap-2 mb-3">
                <div>
                  <h2 class="h5 mb-1">Recent changes</h2>
                  <p class="text-body-secondary mb-0 small">Latest item and stock updates from the kitchen change feed.</p>
                  <p class="text-body-secondary mb-0 small">Saved means the backend created or updated a record.</p>
                </div>
                <button class="btn btn-outline-secondary btn-sm" @click="refreshChanges()" :disabled="changesState.isLoading">
                  <span x-show="!changesState.isLoading">Refresh</span>
                  <span x-show="changesState.isLoading">Refreshing...</span>
                </button>
              </div>

              <template x-if="changesState.error">
                <div class="alert alert-warning mb-0" x-text="changesState.error"></div>
              </template>

              <template x-if="!changesState.error && changesState.isLoading && !recentChanges.length">
                <div class="text-body-secondary">Loading changes...</div>
              </template>

              <template x-if="!changesState.error && !changesState.isLoading && !recentChanges.length">
                <div class="text-body-secondary">No recent changes yet.</div>
              </template>

              <template x-if="recentChanges.length">
                <div class="list-group list-group-flush">
                  <template x-for="(change, index) in recentChanges" :key="change.timestamp || index">
                    <div class="list-group-item px-0">
                      <div class="d-flex flex-wrap justify-content-between align-items-center gap-2">
                        <div class="fw-semibold" x-text="changeHeadline(change)"></div>
                        <div class="small text-body-secondary" x-text="formatChangeTimestamp(change.timestamp)"></div>
                      </div>
                      <div class="small text-body-secondary mt-1" x-text="changeStateLine(change)"></div>
                    </div>
                  </template>
                </div>
              </template>
            </div>
          </div>
        </div>
      </div>
    </section>
  `;
}

export function dashboardPageData(store) {
  return {
    showKitchenPicker: false,
    changesState: createAsyncState(),
    recentChanges: [],
    locationLabelByUuid: {},
    itemByUuid: {},
    async init() {
      if (!store.isConnected) {
        return;
      }

      await this.refreshChanges();
    },
    async refreshChanges() {
      await runAsyncState(this.changesState, async () => {
        const payload = await listKitchenChanges(store, { limit: 10 });
        this.recentChanges = payload.changes;
        await this.loadContextForChanges(payload.changes);
      }).catch(() => {});
    },
    async loadContextForChanges(changes) {
      const stockItemUuids = Array.from(new Set(
        changes
          .map((change) => change?.stock?.item_uuid_b64)
          .filter(Boolean),
      ));
      const missingItemUuids = stockItemUuids.filter((uuid) => !this.itemByUuid[uuid]);

      if (missingItemUuids.length) {
        const results = await Promise.allSettled(
          missingItemUuids.map(async (uuid) => {
            try {
              return await getStockEntry(store, uuid);
            } catch (error) {
              const status = error?.status || error?.cause?.status;
              if (status !== 404) {
                throw error;
              }

              return getStockEntry(store, uuid, { allowInactive: true });
            }
          }),
        );

        results.forEach((result) => {
          if (result.status !== 'fulfilled' || !result.value?.uuid_b64) {
            return;
          }

          this.itemByUuid[result.value.uuid_b64] = result.value;
        });
      }

      if (Object.keys(this.locationLabelByUuid).length) {
        return;
      }

      try {
        const { flat } = await fetchLocations(store);
        this.locationLabelByUuid = Object.fromEntries(
          flat
            .filter((location) => location.uuid_b64)
            .map((location) => [location.uuid_b64, location.pathLabel || location.name]),
        );
      } catch {
        this.locationLabelByUuid = {};
      }
    },
    setKitchen(kitchen) {
      store.setActiveKitchen(kitchen);
      this.showKitchenPicker = false;
      store.addAlert({ type: 'success', message: `Working in ${kitchen.name}.` });
      this.locationLabelByUuid = {};
      this.itemByUuid = {};
      this.refreshChanges();
    },
    resolveItemForChange(change) {
      if (change?.item?.uuid_b64) {
        return change.item;
      }

      const stockItemUuid = change?.stock?.item_uuid_b64;
      if (!stockItemUuid) {
        return null;
      }

      return this.itemByUuid[stockItemUuid] || null;
    },
    humanStockType(value) {
      if (!value) {
        return null;
      }

      return value.charAt(0).toUpperCase() + value.slice(1);
    },
    formatQuantity(quantity, uomSymbol) {
      if (quantity === null || quantity === undefined || quantity === '') {
        return null;
      }

      return `${quantity}${uomSymbol ? ` ${uomSymbol}` : ''}`;
    },
    formatLevel(level) {
      if (!level) {
        return null;
      }

      return level.charAt(0).toUpperCase() + level.slice(1);
    },
    formatShortDate(value) {
      if (!value) {
        return null;
      }

      const date = new Date(value);
      if (Number.isNaN(date.getTime())) {
        return String(value);
      }

      return date.toLocaleDateString();
    },
    resolveLocationLabel(change, item) {
      const locationUuid =
        change?.stock?.location_uuid_b64 ||
        item?.location_initial_uuid_b64 ||
        null;
      if (!locationUuid) {
        return null;
      }

      return this.locationLabelByUuid[locationUuid] || locationUuid;
    },
    changeHeadline(change) {
      const item = this.resolveItemForChange(change);
      const itemName = item?.name || 'Unknown item';
      const type = String(change?.type || 'change');
      const action = String(change?.action || 'updated');

      if (action === 'upsert' && type === 'item') {
        return `Item saved: ${itemName}`;
      }

      if (action === 'upsert' && type === 'stock') {
        return `Stock saved: ${itemName}`;
      }

      return `${type} ${action}: ${itemName}`;
    },
    changeStateLine(change) {
      const item = this.resolveItemForChange(change);
      const stock = change?.stock || {};
      const state = [];

      const stockType = this.humanStockType(item?.stock_type);
      if (stockType) {
        state.push(`Type: ${stockType}`);
      }

      const quantity = this.formatQuantity(
        stock.quantity ?? item?.quantity,
        stock.uom_symbol || item?.uom_symbol,
      );
      if (quantity) {
        state.push(`Quantity: ${quantity}`);
      }

      const level = this.formatLevel(stock.level || item?.level);
      if (level) {
        state.push(`Level: ${level}`);
      }

      const expiry = this.formatShortDate(item?.expire_date);
      if (expiry) {
        state.push(`Expires: ${expiry}`);
      }

      const location = this.resolveLocationLabel(change, item);
      if (location) {
        state.push(`Location: ${location}`);
      }

      if (!state.length) {
        return 'Saved (created or updated).';
      }

      return state.join(' • ');
    },
    formatChangeTimestamp(value) {
      if (!value) {
        return 'Unknown time';
      }

      const date = new Date(value);
      if (Number.isNaN(date.getTime())) {
        return String(value);
      }

      return date.toLocaleString();
    },
  };
}