// ── Shopping list (phone-synced card) ──
//
// One card flagged as #einkauf can be "active" at a time. Its body
// is pushed to the relay on every sync.tick; the relay serves a
// phone-friendly checklist at /shopping. Phone taps toggle items in
// place on the relay; hyprcrd pulls those toggles back on the next
// tick and patches the local card.
//
// Phone never changes item text — only check state. Text edits stay
// in hyprcrd, which keeps conflict resolution trivial (last-writer
// wins by timestamp; near-simultaneous edits are extremely unlikely
// for a shopping list).

import { $, api, esc, getCsrf } from './util.js';
import { state } from './state.js';

const ACTIVE_KEY = 'hyprcrd-shopping-active-id';
const LAST_PUSHED_KEY = 'hyprcrd-shopping-last-pushed-ts';
const LAST_SERVER_KEY = 'hyprcrd-shopping-last-server-ts';

function hasEinkaufTag(card) {
    const tags = (card.tags || '').split(',').map(s => s.trim());
    return tags.includes('einkauf') || tags.includes('shopping');
}

function getActiveId() {
    const v = localStorage.getItem(ACTIVE_KEY);
    return v ? String(v) : null;
}

function setActiveId(id) {
    if (id === null || id === '') localStorage.removeItem(ACTIVE_KEY);
    else localStorage.setItem(ACTIVE_KEY, String(id));
    // Reset timestamp cursors so the switch pushes fresh on next tick.
    localStorage.removeItem(LAST_PUSHED_KEY);
    localStorage.removeItem(LAST_SERVER_KEY);
}

function getActiveCard() {
    const id = getActiveId();
    if (!id) return null;
    return state.cards.find(c => String(c.id) === id) || null;
}

// ── Dialog ────────────────────────────────────────────────────────

function openDialog() {
    document.querySelector('.shopping-picker-overlay')?.remove();

    const overlay = document.createElement('div');
    overlay.className = 'shopping-picker-overlay';
    overlay.style.cssText = 'position:fixed;inset:0;background:var(--t-overlay,rgba(0,0,0,0.6));z-index:200;display:flex;align-items:center;justify-content:center;padding:24px;';

    const panel = document.createElement('div');
    panel.style.cssText = 'background:var(--t-surface);border:1px solid var(--t-border);box-shadow:0 8px 32px rgba(0,0,0,0.6);width:100%;max-width:520px;max-height:80vh;display:flex;flex-direction:column;';
    panel.innerHTML = `
        <div class="flex items-center gap-3 px-5 py-3 border-b border-t-border">
            <i class="ph ph-shopping-cart text-t-accent text-base"></i>
            <h2 class="font-pixel text-sm text-t-accent flex-1">Einkaufsliste</h2>
            <button class="shopping-picker-close text-t-muted hover:text-t-danger"><i class="ph ph-x text-sm"></i></button>
        </div>
        <div class="px-5 py-3 text-[11px] text-t-muted leading-relaxed">
            Karten mit Tag <span class="text-t-accent">#einkauf</span> oder
            <span class="text-t-accent">#shopping</span> können als aktive Liste fürs Telefon
            gewählt werden. Nur eine ist aktiv; ihr Body wird bei jedem Sync zum Relay geschickt
            und unter <span class="text-t-accent">/shopping</span> angezeigt.
        </div>
        <div class="flex-1 overflow-y-auto px-2 py-2" id="shopping-picker-list"></div>
        <div class="flex items-center gap-2 px-5 py-3 border-t border-t-border">
            <span id="shopping-picker-status" class="font-pixel text-[10px] text-t-dim flex-1"></span>
            <button class="shopping-picker-cancel px-3 py-1.5 text-xs border border-t-border text-t-muted hover:border-t-danger hover:text-t-danger"><span class="font-pixel text-[10px]">Close</span></button>
            <button class="shopping-picker-save px-3 py-1.5 text-xs border border-t-accent text-t-accent hover:bg-t-accent/10"><span class="font-pixel text-[10px]">Save</span></button>
        </div>
    `;
    overlay.appendChild(panel);
    document.body.appendChild(overlay);

    const list = panel.querySelector('#shopping-picker-list');
    const status = panel.querySelector('#shopping-picker-status');
    const close = () => overlay.remove();
    panel.querySelector('.shopping-picker-close').addEventListener('click', close);
    panel.querySelector('.shopping-picker-cancel').addEventListener('click', close);
    overlay.addEventListener('click', (e) => { if (e.target === overlay) close(); });
    document.addEventListener('keydown', function esc(e) {
        if (e.key === 'Escape') { close(); document.removeEventListener('keydown', esc); }
    });

    const candidates = state.cards.filter(hasEinkaufTag);
    const currentActive = getActiveId();
    let selectedId = currentActive;

    if (!candidates.length) {
        list.innerHTML = `<div class="px-4 py-6 text-center text-[11px] text-t-dim">
            Keine Karten mit dem Tag <span class="text-t-accent">#einkauf</span>.
            Lege eine Karte mit Checkbox-Items an und gib ihr den Tag, dann erscheint sie hier.
        </div>`;
    } else {
        list.innerHTML = candidates.map(c => {
            const id = String(c.id);
            const checked = id === selectedId ? 'checked' : '';
            const items = (c.body || '').split('\n').filter(l => /^\s*-\s*\[[ xX]\]/.test(l));
            const open = items.filter(l => /^\s*-\s*\[\s\]/.test(l)).length;
            return `<label class="flex items-start gap-3 px-3 py-2 hover:bg-t-raised cursor-pointer">
                <input type="radio" name="shopping-active" value="${id}" ${checked} style="margin-top:3px;">
                <div class="flex-1 min-w-0">
                    <div class="text-xs text-t-bright font-pixel">${esc(c.title || '(untitled)')}</div>
                    <div class="text-[10px] text-t-dim font-pixel mt-0.5">${open} offen · ${items.length} gesamt</div>
                </div>
            </label>`;
        }).join('');
        // "No active" option — explicit way to stop syncing.
        list.insertAdjacentHTML('beforeend', `<label class="flex items-center gap-3 px-3 py-2 border-t border-t-border hover:bg-t-raised cursor-pointer mt-2">
            <input type="radio" name="shopping-active" value="" ${currentActive ? '' : 'checked'} style="margin-top:0;">
            <span class="text-[11px] text-t-muted italic">(keine aktive Liste)</span>
        </label>`);
        list.querySelectorAll('input[name="shopping-active"]').forEach(r => {
            r.addEventListener('change', () => { selectedId = r.value || null; });
        });
    }

    panel.querySelector('.shopping-picker-save').addEventListener('click', async () => {
        const prev = getActiveId();
        setActiveId(selectedId);
        status.textContent = 'saving…';
        try {
            if (selectedId) await pushActive();
            else await clearRemote();
            status.textContent = 'saved';
            setTimeout(close, 400);
        } catch (e) {
            status.textContent = 'error: ' + (e?.message || e);
            status.style.color = 'var(--t-danger)';
            setActiveId(prev);
        }
    });
}

// ── Sync ───────────────────────────────────────────────────────

async function pushActive() {
    const card = getActiveCard();
    if (!card) return;
    const localTs = card.updated_at || new Date().toISOString().replace('T', ' ').slice(0, 19);
    const lastPushed = localStorage.getItem(LAST_PUSHED_KEY);
    if (lastPushed && lastPushed >= localTs) return; // nothing newer
    const res = await api('api/shopping', {
        method: 'POST',
        body: { card_uid: String(card.id), title: card.title || '', body: card.body || '', updated_at: localTs },
    });
    if (res?.ok) {
        localStorage.setItem(LAST_PUSHED_KEY, localTs);
        if (res.updated_at_server) localStorage.setItem(LAST_SERVER_KEY, res.updated_at_server);
    }
}

async function pullActive() {
    const card = getActiveCard();
    if (!card) return;
    const res = await api('api/shopping', { method: 'GET' });
    if (!res?.ok || !res.state) return;
    const { card_uid, body, updated_at_server } = res.state;
    if (String(card_uid) !== String(card.id)) return; // relay still has a previous list
    const seen = localStorage.getItem(LAST_SERVER_KEY);
    if (seen && seen >= updated_at_server) return; // no news
    if ((body || '') === (card.body || '')) {
        localStorage.setItem(LAST_SERVER_KEY, updated_at_server);
        return;
    }
    // Phone toggled something — patch the local card.
    await api(`api/cards/${card.id}`, { method: 'PATCH', body: { body } });
    localStorage.setItem(LAST_SERVER_KEY, updated_at_server);
    localStorage.setItem(LAST_PUSHED_KEY, updated_at_server); // suppress immediate re-push
    await window._reloadAll?.();
}

async function clearRemote() {
    // No DELETE endpoint — send an empty list that "displaces" the
    // previous active card on the relay so the phone sees nothing.
    await api('api/shopping', {
        method: 'POST',
        body: { card_uid: '__inactive__', title: '', body: '', updated_at: new Date().toISOString().replace('T', ' ').slice(0, 19) },
    });
    localStorage.removeItem(LAST_PUSHED_KEY);
    localStorage.removeItem(LAST_SERVER_KEY);
}

async function tick() {
    if (!getActiveId()) return;
    // Pull first so phone toggles land before we overwrite with a push.
    try { await pullActive(); } catch {}
    try { await pushActive(); } catch {}
}

// ── Hamburger menu wiring ─────────────────────────────────────

function initMenu() {
    const btn = $('header-menu-btn');
    const menu = $('header-menu');
    if (!btn || !menu) return;
    btn.addEventListener('click', (e) => {
        e.stopPropagation();
        menu.classList.toggle('hidden');
    });
    document.addEventListener('click', (e) => {
        if (!menu.contains(e.target) && e.target !== btn) menu.classList.add('hidden');
    });
    $('menu-shopping')?.addEventListener('click', () => {
        menu.classList.add('hidden');
        openDialog();
    });
}

export function initShopping() {
    initMenu();
    // Hook into the shared sync heartbeat so push/pull happens on the
    // same cadence as every other poller — one timer rules them all.
    window.hyprcrd?.hooks?.on?.('sync.tick', () => { tick().catch(() => {}); });
    // Also push right after a save of the active card so the phone
    // sees edits without waiting for the next tick.
    window.addEventListener('hyprcrd:editor-close', (e) => {
        const active = getActiveId();
        if (active && String(e?.detail?.cardId) === active) {
            // Small delay so state.cards has the post-save body.
            setTimeout(() => tick().catch(() => {}), 300);
        }
    });
}