import {
    INGREDIENTS,
    CATEGORY_LABELS,
    pantryQtyStep,
} from '../data/catalog.js';
import { addIngredientToKitchenList, categoryLabel, loadPantry, setPantryQty } from '../services/pantryShopping.js';
import { showAppToast } from '../ui/toast.js';

/* ── helpers ── */

function esc(s) {
    return String(s).replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;');
}

function unitLabel(u) {
    return u === 'szt' ? 'szt.' : u;
}

function normalizeSearch(q) {
    return String(q).trim().toLowerCase();
}

const CATEGORY_ICONS = {
    pieczywo: 'fa-bread-slice',
    nabial: 'fa-cheese',
    mieso_ryby: 'fa-drumstick-bite',
    warzywa: 'fa-carrot',
    owoce: 'fa-apple-whole',
    suche: 'fa-wheat-awn',
    przyprawy: 'fa-leaf',
    inne: 'fa-jar',
};

/* ── state ── */

let showOnlyStock = false;
let editingId = null;
/** @type {Set<string>} */
const selectedCategories = new Set();

let editShopStep = 1;
let editShopUsesPacks = false;

const BOTTOM = '5.25rem';
const HIDDEN_Y = `translateY(calc(100% + ${BOTTOM}))`;

/* ══════════════════════ HTML SHELL ══════════════════════ */

export function getPantryHTML() {
    return `
    <div id="pantry-view" class="hidden flex flex-col h-full absolute inset-0 overflow-hidden bg-gray-50 z-10 pb-24">
        <div class="shrink-0 bg-white border-b border-gray-100 mt-3 px-4 pt-2 pb-2.5 space-y-2">
            <div class="flex items-center gap-2.5 bg-gray-100 rounded-2xl px-3.5 py-2.5 focus-within:ring-2 focus-within:ring-gray-900/10 transition-all">
                <i class="fas fa-search text-gray-400 text-xs"></i>
                <input type="search" id="pantry-search" autocomplete="off" placeholder="Szukaj produktu…"
                    class="flex-1 bg-transparent outline-none text-sm text-gray-800 placeholder-gray-400" />
            </div>
            <div id="pantry-category-chips" class="flex gap-2 overflow-x-auto no-scrollbar -mx-1 px-1 pb-0.5"></div>
            <div class="flex items-center justify-end">
                <label class="flex items-center gap-2 cursor-pointer select-none">
                    <span class="text-xs font-medium text-gray-500">Tylko na stanie</span>
                    <button type="button" id="pantry-stock-toggle" role="switch" aria-checked="false"
                        class="relative w-10 h-[22px] rounded-full bg-gray-200 transition-colors duration-200 shrink-0">
                        <span class="absolute left-0.5 top-0.5 w-[18px] h-[18px] bg-white rounded-full shadow-sm transition-transform duration-200"></span>
                    </button>
                </label>
            </div>
        </div>

        <div id="pantry-scroll" class="flex-1 overflow-y-auto no-scrollbar">
            <div id="pantry-board" class="px-4 pt-3 pb-4 space-y-2"></div>
        </div>

        <!-- ── product sheet ── -->
        <div id="pv2-edit-bg" class="absolute inset-0 z-[38] bg-black/40 hidden opacity-0 transition-opacity duration-200"></div>
        <div id="pv2-edit-sheet" class="absolute left-0 right-0 z-[40] bg-white rounded-t-3xl shadow-[0_-10px_40px_rgba(0,0,0,0.12)] px-5 pt-2 pb-4 flex flex-col gap-2.5 max-h-[75%] min-h-0 overflow-y-auto no-scrollbar"
            style="bottom:${BOTTOM};transform:${HIDDEN_Y};transition:transform 300ms cubic-bezier(.32,.72,0,1)">
            <div class="w-10 h-1 bg-gray-200 rounded-full mx-auto shrink-0"></div>

            <div class="shrink-0">
                <h2 id="pv2-edit-name" class="text-[15px] font-bold text-gray-900 leading-snug"></h2>
                <p id="pv2-edit-meta" class="text-[11px] text-gray-500"></p>
            </div>

            <div class="shrink-0 flex items-center gap-2">
                <span class="text-[10px] font-semibold uppercase tracking-wider text-gray-400 w-[3.2rem] shrink-0">Zapas</span>
                <button type="button" id="pv2-edit-minus" class="w-9 h-9 rounded-xl bg-gray-100 text-gray-700 hover:bg-gray-200 flex items-center justify-center transition-colors active:scale-95 shrink-0">
                    <i class="fas fa-minus text-xs"></i>
                </button>
                <div class="flex items-baseline gap-0.5">
                    <input type="number" id="pv2-edit-qty" min="0" step="1" inputmode="decimal"
                        class="w-14 text-center text-lg font-bold tabular-nums bg-transparent outline-none" value="0" />
                    <span id="pv2-edit-unit" class="text-xs text-gray-400 font-medium"></span>
                </div>
                <button type="button" id="pv2-edit-plus" class="w-9 h-9 rounded-xl bg-gray-100 text-gray-700 hover:bg-gray-200 flex items-center justify-center transition-colors active:scale-95 shrink-0">
                    <i class="fas fa-plus text-xs"></i>
                </button>
            </div>

            <div class="border-t border-gray-100 shrink-0"></div>

            <div class="shrink-0 space-y-1">
                <div class="flex items-center gap-2">
                    <span class="text-[10px] font-semibold uppercase tracking-wider text-gray-400 w-[3.2rem] shrink-0">Lista</span>
                    <button type="button" id="pv2-shop-minus" class="w-9 h-9 rounded-xl bg-gray-100 text-gray-700 hover:bg-gray-200 flex items-center justify-center transition-colors active:scale-95 shrink-0">
                        <i class="fas fa-minus text-xs"></i>
                    </button>
                    <div class="flex items-baseline gap-0.5">
                        <input type="number" id="pv2-shop-qty" min="1" step="1" inputmode="numeric"
                            class="w-14 text-center text-lg font-bold tabular-nums bg-transparent outline-none" value="1" />
                        <span id="pv2-shop-unit" class="text-xs text-gray-400 font-medium"></span>
                    </div>
                    <button type="button" id="pv2-shop-plus" class="w-9 h-9 rounded-xl bg-gray-100 text-gray-700 hover:bg-gray-200 flex items-center justify-center transition-colors active:scale-95 shrink-0">
                        <i class="fas fa-plus text-xs"></i>
                    </button>
                    <button type="button" id="pv2-shop-add" class="ml-auto shrink-0 px-3.5 py-2 rounded-xl bg-gray-900 text-white text-[11px] font-semibold hover:bg-black transition-colors active:scale-95">
                        <i class="fas fa-cart-plus text-[9px] mr-1"></i>Dodaj
                    </button>
                </div>
                <p id="pv2-shop-hint" class="text-[10px] text-gray-400 pl-[3.5rem]"></p>
            </div>

            <div id="pv2-edit-nutrition" class="shrink-0"></div>
        </div>
    </div>`;
}

/* ══════════════════════ CATEGORY CHIPS (multi-select) ══════════════════════ */

function allCategoryKeys() {
    const s = new Set();
    Object.values(INGREDIENTS).forEach(d => s.add(d.category));
    return [...s].sort((a, b) => categoryLabel(a).localeCompare(categoryLabel(b)));
}

function renderCategoryChips() {
    const wrap = document.getElementById('pantry-category-chips');
    if (!wrap) return;

    const keys = allCategoryKeys();
    wrap.innerHTML = keys.map(k => {
        const active = selectedCategories.has(k);
        const icon = CATEGORY_ICONS[k] || 'fa-jar';
        const cls = active
            ? 'shrink-0 inline-flex items-center gap-1.5 px-3.5 py-2 rounded-full text-xs font-semibold bg-gray-900 text-white transition-colors'
            : 'shrink-0 inline-flex items-center gap-1.5 px-3.5 py-2 rounded-full text-xs font-semibold bg-gray-100 text-gray-600 hover:bg-gray-200 transition-colors';
        return `<button type="button" data-cat="${esc(k)}" class="pv2-cat-chip ${cls}"><i class="fas ${icon} text-[10px]"></i>${esc(categoryLabel(k))}</button>`;
    }).join('');

    wrap.querySelectorAll('.pv2-cat-chip').forEach(btn => {
        btn.addEventListener('click', () => {
            const cat = btn.dataset.cat;
            if (selectedCategories.has(cat)) selectedCategories.delete(cat);
            else selectedCategories.add(cat);
            renderCategoryChips();
            renderBoard();
        });
    });
}

/* ══════════════════════ BOARD RENDERING ══════════════════════ */

function getFilteredIds(searchRaw) {
    const q = normalizeSearch(searchRaw);
    return Object.keys(INGREDIENTS).filter(id => {
        const d = INGREDIENTS[id];
        if (selectedCategories.size > 0 && !selectedCategories.has(d.category)) return false;
        if (!q) return true;
        return d.name.toLowerCase().includes(q) || (CATEGORY_LABELS[d.category] || '').toLowerCase().includes(q);
    }).sort((a, b) => INGREDIENTS[a].name.localeCompare(INGREDIENTS[b].name, 'pl'));
}

function chipHtml(id, pantry) {
    const def = INGREDIENTS[id];
    const qty = Number(pantry[id]) || 0;
    const u = unitLabel(def.pantryUnit);

    if (qty > 0) {
        return `<button type="button" class="pv2-chip inline-flex flex-col items-start px-3.5 py-2.5 rounded-xl bg-emerald-50 border border-emerald-200/80 text-left hover:bg-emerald-100/80 transition-colors active:scale-[0.96]" data-id="${esc(id)}">
            <span class="text-[13px] font-semibold text-gray-900 leading-tight whitespace-nowrap">${esc(def.name)}</span>
            <span class="text-[11px] text-emerald-600 font-semibold tabular-nums leading-tight mt-0.5">${Math.round(qty)} ${esc(u)}</span>
        </button>`;
    }

    return `<button type="button" class="pv2-chip inline-flex items-center px-3.5 py-2.5 rounded-xl border border-dashed border-gray-200 text-left hover:border-gray-300 hover:bg-white transition-colors active:scale-[0.96] group" data-id="${esc(id)}">
        <span class="text-[13px] font-medium text-gray-400 group-hover:text-gray-600 whitespace-nowrap transition-colors">${esc(def.name)}</span>
        <i class="fas fa-plus text-[8px] text-gray-300 group-hover:text-gray-500 ml-1.5 transition-colors"></i>
    </button>`;
}

function groupByCategory(ids) {
    /** @type {Map<string, string[]>} */
    const groups = new Map();
    for (const id of ids) {
        const cat = INGREDIENTS[id].category;
        if (!groups.has(cat)) groups.set(cat, []);
        groups.get(cat).push(id);
    }
    return [...groups.keys()]
        .sort((a, b) => categoryLabel(a).localeCompare(categoryLabel(b)))
        .map(cat => ({ cat, ids: groups.get(cat) }));
}

function renderBoard() {
    const root = document.getElementById('pantry-board');
    if (!root) return;

    const q = document.getElementById('pantry-search')?.value || '';
    const pantry = loadPantry();
    const allFiltered = getFilteredIds(q);
    const visible = showOnlyStock
        ? allFiltered.filter(id => (Number(pantry[id]) || 0) > 0)
        : allFiltered;

    if (visible.length === 0) {
        root.innerHTML = showOnlyStock
            ? `<div class="flex flex-col items-center justify-center py-16 text-center">
                <div class="w-16 h-16 rounded-full bg-gray-100 flex items-center justify-center mb-4">
                    <i class="fas fa-box-open text-2xl text-gray-300"></i>
                </div>
                <p class="text-sm font-semibold text-gray-700">Nic na stanie</p>
                <p class="text-xs text-gray-500 mt-1 max-w-[220px] leading-relaxed">Wyłącz filtr, aby zobaczyć cały katalog produktów</p>
            </div>`
            : `<p class="text-sm text-gray-500 text-center py-10">Brak wyników — zmień wyszukiwanie lub filtry.</p>`;
        return;
    }

    const groups = groupByCategory(visible);
    let html = '';
    for (const { cat, ids } of groups) {
        const icon = CATEGORY_ICONS[cat] || 'fa-jar';
        html += `
        <div class="mb-4 last:mb-0">
            <p class="text-xs font-semibold text-gray-400 uppercase tracking-wider mb-2 px-0.5">
                <i class="fas ${icon} text-[10px] mr-1"></i>${esc(categoryLabel(cat))}
            </p>
            <div class="flex flex-wrap gap-2">${ids.map(id => chipHtml(id, pantry)).join('')}</div>
        </div>`;
    }

    root.innerHTML = html;

    root.querySelectorAll('.pv2-chip').forEach(btn => {
        btn.addEventListener('click', () => openEditSheet(btn.dataset.id));
    });
}

/* ══════════════════════ STOCK TOGGLE ══════════════════════ */

function updateToggleVisuals() {
    const btn = document.getElementById('pantry-stock-toggle');
    if (!btn) return;
    const thumb = btn.querySelector('span');
    btn.setAttribute('aria-checked', String(showOnlyStock));
    if (showOnlyStock) {
        btn.classList.remove('bg-gray-200');
        btn.classList.add('bg-emerald-500');
        thumb?.classList.add('translate-x-[18px]');
    } else {
        btn.classList.add('bg-gray-200');
        btn.classList.remove('bg-emerald-500');
        thumb?.classList.remove('translate-x-[18px]');
    }
}

/* ══════════════════════ EDIT BOTTOM SHEET ══════════════════════ */

function openEditSheet(ingredientId) {
    const def = INGREDIENTS[ingredientId];
    if (!def) return;
    editingId = ingredientId;

    const pantry = loadPantry();
    const qty = Number(pantry[ingredientId]) || 0;
    const u = unitLabel(def.pantryUnit);
    const step = pantryQtyStep(ingredientId);
    const pack = def.purchasePack;

    const nameEl = document.getElementById('pv2-edit-name');
    if (nameEl) nameEl.textContent = def.name;

    const metaEl = document.getElementById('pv2-edit-meta');
    if (metaEl) {
        let meta = categoryLabel(def.category);
        if (pack) meta += ` · ${pack.label || `${pack.amount} ${u}`}`;
        metaEl.textContent = meta;
    }

    const qtyEl = document.getElementById('pv2-edit-qty');
    if (qtyEl) qtyEl.value = qty > 0 ? String(Math.round(qty)) : '0';

    const unitEl = document.getElementById('pv2-edit-unit');
    if (unitEl) unitEl.textContent = u;

    editShopUsesPacks = Boolean(pack && pack.amount > 0);
    editShopStep = editShopUsesPacks ? 1 : step;

    const shopQtyEl = document.getElementById('pv2-shop-qty');
    if (shopQtyEl) shopQtyEl.value = String(editShopStep);

    const shopUnitEl = document.getElementById('pv2-shop-unit');
    if (shopUnitEl) shopUnitEl.textContent = editShopUsesPacks ? 'opak.' : u;

    const shopHintEl = document.getElementById('pv2-shop-hint');
    if (shopHintEl) {
        if (editShopUsesPacks) {
            const lab = pack.label || `${pack.amount} ${u}`;
            shopHintEl.textContent = `1 opak. = ${lab}`;
        } else {
            shopHintEl.textContent = '';
        }
    }

    renderNutritionInSheet(def);

    const bg = document.getElementById('pv2-edit-bg');
    const sheet = document.getElementById('pv2-edit-sheet');
    if (!bg || !sheet) return;
    bg.classList.remove('hidden');
    sheet.classList.remove('hidden');
    requestAnimationFrame(() => {
        bg.classList.remove('opacity-0');
        sheet.style.transform = 'translateY(0)';
    });
}

function nutritionListRow(label, valueHtml) {
    return `<li class="flex items-baseline justify-between gap-3 py-0.5 border-b border-gray-100/80 last:border-0">
        <span class="text-gray-500 shrink-0">${esc(label)}</span>
        <span class="text-right font-semibold tabular-nums text-gray-800">${valueHtml}</span>
    </li>`;
}

function renderNutritionInSheet(def) {
    const wrap = document.getElementById('pv2-edit-nutrition');
    if (!wrap) return;
    const n = def.nutritionPer100g;
    if (!n) { wrap.innerHTML = ''; return; }

    const refLabel = def.pantryUnit === 'ml' ? '100 ml produktu' : '100 g produktu';
    wrap.innerHTML = `
    <div class="text-[10px] leading-snug mt-0.5 pt-2 border-t border-gray-100 space-y-1">
        <p class="text-[9px] font-semibold uppercase tracking-wide text-gray-500 px-0.5">${esc(refLabel)}</p>
        <ul class="space-y-0 rounded-lg bg-white/70 px-2 py-1 ring-1 ring-gray-100/90">
            ${nutritionListRow('Energia', `${n.kcal} kcal`)}
            ${nutritionListRow('Białko', `${n.protein} g`)}
            ${nutritionListRow('Tłuszcz', `${n.fat} g`)}
            ${nutritionListRow('Węglowodany', `${n.carbs} g`)}
        </ul>
    </div>`;
}

function closeEditSheet() {
    editingId = null;
    const bg = document.getElementById('pv2-edit-bg');
    const sheet = document.getElementById('pv2-edit-sheet');
    if (sheet) sheet.style.transform = HIDDEN_Y;
    if (bg) bg.classList.add('opacity-0');
    setTimeout(() => {
        bg?.classList.add('hidden');
        sheet?.classList.add('hidden');
    }, 300);
    renderBoard();
}

function getEditQty() {
    const el = document.getElementById('pv2-edit-qty');
    return Math.max(0, parseFloat(String(el?.value).replace(',', '.')) || 0);
}

function setEditQty(v) {
    const el = document.getElementById('pv2-edit-qty');
    if (el) el.value = String(Math.max(0, Math.round(v)));
}

function applyEditQty(newQty) {
    if (!editingId) return;
    const v = Math.max(0, Math.round(Number(newQty) * 1000) / 1000 || 0);
    setPantryQty(editingId, v);
    setEditQty(v);
}

function readShopQty() {
    const el = document.getElementById('pv2-shop-qty');
    return Math.max(1, Math.round(parseFloat(String(el?.value).replace(',', '.')) || 0));
}

function setShopQty(v) {
    const el = document.getElementById('pv2-shop-qty');
    if (el) el.value = String(Math.max(1, Math.round(Number(v))));
}

function bindEditSheet() {
    document.getElementById('pv2-edit-bg')?.addEventListener('click', closeEditSheet);

    document.getElementById('pv2-edit-minus')?.addEventListener('click', () => {
        if (!editingId) return;
        applyEditQty(Math.max(0, getEditQty() - pantryQtyStep(editingId)));
    });

    document.getElementById('pv2-edit-plus')?.addEventListener('click', () => {
        if (!editingId) return;
        applyEditQty(getEditQty() + pantryQtyStep(editingId));
    });

    document.getElementById('pv2-edit-qty')?.addEventListener('change', () => {
        applyEditQty(getEditQty());
    });

    document.getElementById('pv2-shop-minus')?.addEventListener('click', () => {
        setShopQty(Math.max(1, readShopQty() - editShopStep));
    });

    document.getElementById('pv2-shop-plus')?.addEventListener('click', () => {
        setShopQty(readShopQty() + editShopStep);
    });

    document.getElementById('pv2-shop-qty')?.addEventListener('change', () => {
        setShopQty(readShopQty());
    });

    document.getElementById('pv2-shop-add')?.addEventListener('click', () => {
        if (!editingId) return;
        const def = INGREDIENTS[editingId];
        if (!def) return;
        const count = readShopQty();
        const u = unitLabel(def.pantryUnit);

        if (editShopUsesPacks && def.purchasePack) {
            const packAmt = def.purchasePack.amount;
            const total = count * packAmt;
            const note = `${count}× ${def.purchasePack.label || `${packAmt} ${u}`}`;
            addIngredientToKitchenList(editingId, total, note);
            showAppToast(`Dodano ${count} op. (${total} ${u}) na listę.`);
        } else {
            addIngredientToKitchenList(editingId, count);
            showAppToast(`Dodano ${count} ${u} na listę.`);
        }
        window.refreshShopping?.();
    });
}

/* ══════════════════════ PUBLIC API ══════════════════════ */

export function refreshPantry() {
    renderCategoryChips();
    renderBoard();
}

export function setupPantry() {
    renderCategoryChips();
    renderBoard();
    bindEditSheet();

    document.getElementById('pantry-search')?.addEventListener('input', () => renderBoard());

    document.getElementById('pantry-stock-toggle')?.addEventListener('click', () => {
        showOnlyStock = !showOnlyStock;
        updateToggleVisuals();
        renderBoard();
    });

    window.refreshPantry = refreshPantry;
}
