/**
 * salestax-view.js — manuelle Sales-Tax-Verwaltung
 *
 * Aus accounting-view.js herausgelöst (vormals Sektion "Sales Tax" dort).
 * Logik unverändert übernommen; angepasst wurden ausschließlich:
 *   - der onclick-Namespace: window.accountingView.X() → window.salesTaxView.X()
 *   - Helper kommen jetzt aus ../utils/report-helpers.js statt modul-lokal
 *   - der Sektions-Klapper makeCollapsible('Sales Tax', …) entfällt ersatzlos
 *
 * Hinweis: openTaxPeriodDetail() ruft API.accounting.getTaxSummary() auf —
 * dieselbe QBO-Schnittstelle, die der Report "Sales Tax (QBO)" auf dem
 * Reports-Tab nutzt. Die Abhängigkeit liegt auf API-Ebene, die Trennung der
 * beiden Oberflächen berührt sie nicht.
 *
 * Maßgeblichkeit der Beträge: Sobald eine Periode in sales_tax_periods steht,
 * ist der dort gespeicherte QBO-Snapshot (tax_collected & Co.) der angezeigte
 * Grundbetrag. Der Live-Abruf liefert dann nur noch die Distrikt-Aufschlüsselung.
 * Nur für eine noch nicht gespeicherte Periode kommen die Kennzahlen live.
 */

import '../utils/api.js';
import { formatDate } from '../utils/helpers.js';
import {
    fmtMoney, escapeHtml, showError, showLoading,
    todayISO, firstOfMonthISO, lastOfMonthISO, prevMonthISO,
    renderQboReport
} from '../utils/report-helpers.js';

// ────────────────────────────────────────────────────────────────────
// State (modul-lokal)
// ────────────────────────────────────────────────────────────────────

let stPeriods = [];
let stEditingPeriodId = null;  // current period in detail dialog, null = new
let stCurrentTaxData = null;   // parsed data for the open detail dialog

// ────────────────────────────────────────────────────────────────────
// Sales Tax Periods
// ────────────────────────────────────────────────────────────────────

export function injectSalesTaxSection() {
    const c = document.getElementById('salestax-content');
    if (!c) return;
    c.innerHTML = `
        <div class="bg-white rounded-lg shadow-sm border border-gray-200 overflow-hidden">
            <div class="px-4 py-3 border-b bg-gray-50 flex flex-wrap items-center gap-3">
                <h3 class="font-semibold text-gray-800 text-sm">Period Overview</h3>
                <div class="ml-auto flex gap-2">
                    <button onclick="window.salesTaxView.openNewTaxPeriod()"
                            class="px-3 py-1.5 bg-blue-600 text-white rounded-md text-sm font-medium hover:bg-blue-700">
                        + New Period
                    </button>
                </div>
            </div>
            <div id="sales-tax-periods-table"></div>
        </div>
        <div id="sales-tax-detail" class="mt-4 hidden"></div>`;
}

export async function loadTaxPeriods() {
    try {
        stPeriods = await window.API.accounting.getTaxPeriods() || [];
    } catch (e) {
        stPeriods = [];
        console.error('Failed to load tax periods:', e.message);
    }
    renderTaxPeriodsTable();
}

function renderTaxPeriodsTable() {
    const el = document.getElementById('sales-tax-periods-table');
    if (!el) return;

    if (!stPeriods.length) {
        el.innerHTML = `<div class="p-4 text-gray-500 text-sm">No sales tax periods recorded yet. Click "+ New Period" to get started.</div>`;
        return;
    }

    const rows = stPeriods.map(p => {
        const pStatus = p.status || (p.qbo_journal_entry_id ? 'booked' : 'open');
        let statusHtml, statusColor;
        if (pStatus === 'booked')      { statusHtml = 'Booked';   statusColor = 'bg-green-100 text-green-800'; }
        else if (pStatus === 'external' || pStatus === 'paid') { statusHtml = 'Paid'; statusColor = 'bg-green-100 text-green-800'; }
        else                            { statusHtml = 'Open';     statusColor = 'bg-yellow-100 text-yellow-800'; }

        const [py, pm] = String(p.period_start).split('T')[0].split('-');
        const monthLabel = new Date(Number(py), Number(pm) - 1).toLocaleDateString('en-US', { year: 'numeric', month: 'long', timeZone: 'UTC' });
        const adj = parseFloat(p.adjustment_amount) || 0;
        const adjStr = adj !== 0 ? (adj > 0 ? `−$${adj.toFixed(2)}` : `+$${Math.abs(adj).toFixed(2)}`) : '—';
        const netPaid = parseFloat(p.net_paid) || parseFloat(p.tax_collected) || 0;
        const paidOn = (pStatus === 'external' || pStatus === 'paid' || pStatus === 'booked')
            ? (p.booked_at ? formatDate(p.booked_at) : '—') : '—';

        return `
            <tr class="border-t hover:bg-gray-50">
                <td class="px-3 py-2 text-sm font-medium text-gray-800">${monthLabel}</td>
                <td class="px-3 py-2 text-sm">
                    <span class="inline-flex items-center px-2 py-0.5 rounded-full text-xs font-semibold ${statusColor}">${statusHtml}</span>
                </td>
                <td class="px-3 py-2 text-sm text-right">${fmtMoney(parseFloat(p.tax_collected) || 0)}</td>
                <td class="px-3 py-2 text-sm text-right">${adjStr}</td>
                <td class="px-3 py-2 text-sm text-right font-semibold">${fmtMoney(netPaid)}</td>
                <td class="px-3 py-2 text-sm text-gray-500">${paidOn}</td>
                <td class="px-3 py-2 text-sm text-center">
                    <button onclick="window.salesTaxView.openTaxPeriod(${p.id})"
                            class="text-blue-600 hover:text-blue-800 text-xs font-medium">View summary</button>
                </td>
            </tr>`;
    }).join('');

    el.innerHTML = `
        <div class="overflow-x-auto">
            <table class="min-w-full text-sm">
                <thead class="bg-gray-50">
                    <tr>
                        <th class="px-3 py-2 text-left font-medium text-gray-700">Period</th>
                        <th class="px-3 py-2 text-left font-medium text-gray-700">Status</th>
                        <th class="px-3 py-2 text-right font-medium text-gray-700">Tax Amount</th>
                        <th class="px-3 py-2 text-right font-medium text-gray-700">Adjustment</th>
                        <th class="px-3 py-2 text-right font-medium text-gray-700">Net Due</th>
                        <th class="px-3 py-2 text-left font-medium text-gray-700">Paid On</th>
                        <th class="px-3 py-2 text-center font-medium text-gray-700">Actions</th>
                    </tr>
                </thead>
                <tbody>${rows}</tbody>
            </table>
            <div class="px-3 py-2 text-xs text-gray-500 border-t bg-gray-50">${stPeriods.length} period${stPeriods.length === 1 ? '' : 's'}</div>
        </div>`;
}

export async function openNewTaxPeriod() {
    const [y, m] = prevMonthISO().split('-').map(Number);
    const startDate = firstOfMonthISO(y, m - 1);
    const endDate = lastOfMonthISO(y, m - 1);
    await openTaxPeriodDetail(startDate, endDate, null);
}

export async function openTaxPeriod(periodId) {
    const period = stPeriods.find(p => p.id === periodId);
    if (!period) return alert('Period not found.');
    await openTaxPeriodDetail(period.period_start, period.period_end, period);
}

async function openTaxPeriodDetail(startDate, endDate, existingPeriod) {
    const detailEl = document.getElementById('sales-tax-detail');
    if (!detailEl) return;

    stEditingPeriodId = existingPeriod ? existingPeriod.id : null;

    if (existingPeriod && existingPeriod.status === 'paid') {
        const [py, pm] = String(existingPeriod.period_start).split('T')[0].split('-');
        const MONTHS = ['January','February','March','April','May','June','July','August','September','October','November','December'];
        const mLabel = MONTHS[Number(pm) - 1] + ' ' + py;
        const adj = parseFloat(existingPeriod.adjustment_amount) || 0;
        const adjStr = adj > 0 ? `−${fmtMoney(adj)}` : adj < 0 ? `+$${Math.abs(adj).toFixed(2)}` : '—';
        const paidOn = formatDate(existingPeriod.booked_at);

        detailEl.innerHTML = `
            <div class="bg-white rounded-lg shadow-sm border border-gray-200 p-4">
                <div class="flex items-center justify-between mb-3">
                    <h3 class="font-semibold text-gray-800">${mLabel} — Sales Tax Detail (Paid)</h3>
                    <button onclick="window.salesTaxView.closeTaxPeriodDetail()" class="px-2 py-1 text-gray-400 hover:text-gray-600 text-lg leading-none">&times;</button>
                </div>
                <p class="text-sm text-green-700 font-semibold mb-4">✅ Paid on ${paidOn}</p>
                <table class="min-w-full text-sm border border-gray-200 rounded">
                    <tbody>
                        <tr class="border-t"><td class="px-3 py-2 text-gray-600">Total Sales</td><td class="px-3 py-2 text-right font-medium">${fmtMoney(parseFloat(existingPeriod.total_sales) || 0)}</td></tr>
                        <tr class="border-t"><td class="px-3 py-2 text-gray-600">Nontaxable Sales</td><td class="px-3 py-2 text-right font-medium">${fmtMoney(parseFloat(existingPeriod.nontaxable_sales) || 0)}</td></tr>
                        <tr class="border-t"><td class="px-3 py-2 text-gray-600">Taxable Sales</td><td class="px-3 py-2 text-right font-medium">${fmtMoney(parseFloat(existingPeriod.taxable_sales) || 0)}</td></tr>
                        <tr class="border-t"><td class="px-3 py-2 text-gray-600">Tax Collected</td><td class="px-3 py-2 text-right font-medium">${fmtMoney(parseFloat(existingPeriod.tax_collected) || 0)}</td></tr>
                        <tr class="border-t"><td class="px-3 py-2 text-gray-600">Adjustment</td><td class="px-3 py-2 text-right font-medium ${adj !== 0 ? 'text-red-600' : ''}">${adjStr}</td></tr>
                        ${existingPeriod.adjustment_reason ? `<tr class="border-t"><td class="px-3 py-2 text-gray-500 text-xs pl-8" colspan="2">Reason: ${escapeHtml(existingPeriod.adjustment_reason)}</td></tr>` : ''}
                        <tr class="border-t bg-gray-50 font-semibold"><td class="px-3 py-2">Net Paid</td><td class="px-3 py-2 text-right">${fmtMoney(parseFloat(existingPeriod.net_paid) || 0)}</td></tr>
                    </tbody>
                </table>
            </div>`;
        detailEl.classList.remove('hidden');
        detailEl.scrollIntoView({ behavior: 'smooth' });
        return;
    }

    showLoading('sales-tax-detail', 'Loading tax summary from QBO…');
    let taxData = null;
    try {
        taxData = await window.API.accounting.getTaxSummary(startDate, endDate, 'Accrual');
    } catch (e) {
        // Für eine gespeicherte Periode ist der Live-Abruf nur Beiwerk: die
        // Kennzahlen stehen in der DB-Zeile, also weiter mit dem Snapshot.
        if (!existingPeriod) {
            showError('sales-tax-detail', e.message || 'Failed to load tax summary');
            return;
        }
        console.error('Tax summary fetch failed, showing saved snapshot:', e.message);
    }

    // Gespeicherte Periode → DB-Snapshot ist maßgeblich; der Live-Abruf liefert
    // nur die Distrikt-Zeilen. Neue Periode → live geladene Werte.
    const liveParsed = parseTaxDataFromReport(taxData);
    const useSnapshot = !!existingPeriod;
    const parsed = useSnapshot ? snapshotFromPeriod(existingPeriod, liveParsed) : liveParsed;

    const reportData = useSnapshot ? withSnapshotGrandTotal(taxData, parsed) : taxData;
    const reportHtml = reportData?.Rows
        ? renderQboReport(reportData)
        : `<p class="text-sm text-gray-500">No tax data for this period.</p>`;
    const snapshotNote = useSnapshot
        ? `<p class="mt-2 text-xs text-gray-500">Grand total shown is the saved QBO snapshot for this period${existingPeriod.updated_at ? ` (last saved ${formatDate(existingPeriod.updated_at)})` : ''}. The district rows above are recalculated live and may differ in detail.</p>`
        : '';

    stCurrentTaxData = { ...parsed, startDate, endDate };
    const taxCollected = parsed.taxCollected;
    const totalSales = parsed.totalSales;
    const nontaxable = parsed.nontaxableSales;
    const taxable = parsed.taxableSales;
    const adjustments = existingPeriod?.adjustment_amount != null ? parseFloat(existingPeriod.adjustment_amount) || 0 : 0;
    const adjReason = existingPeriod?.adjustment_reason || '';
    const netPaid = taxCollected - adjustments;
    const periodStatus = existingPeriod?.status || (existingPeriod?.qbo_journal_entry_id ? 'booked' : 'open');
    const isOpen = periodStatus === 'open';
    const isEditable = isOpen;

    const today = todayISO();
    const [y, m] = startDate.split('-').map(Number);
    const monthLabel = new Date(y, m - 1).toLocaleDateString('en-US', { year: 'numeric', month: 'long', timeZone: 'UTC' });

    detailEl.innerHTML = `
        <div class="bg-white rounded-lg shadow-sm border border-gray-200 p-4">
            <div class="flex items-center justify-between mb-3">
                <h3 class="font-semibold text-gray-800">${monthLabel} — Sales Tax Detail</h3>
                <button onclick="window.salesTaxView.closeTaxPeriodDetail()"
                        class="px-2 py-1 text-gray-400 hover:text-gray-600 text-lg leading-none">&times;</button>
            </div>
            ${reportHtml}
            ${snapshotNote}

            <div class="mt-4 border-t pt-4">
                <div class="flex items-center gap-4 text-sm mb-3" id="st-summary-bar">
                    <span><strong>Tax Collected:</strong> ${fmtMoney(taxCollected)}${useSnapshot ? ' <span class="text-xs text-gray-400">(saved)</span>' : ''}</span>
                    <span id="st-adj-display" class="${adjustments !== 0 ? 'text-red-600' : ''}"><strong>Adjustment:</strong> ${adjustments > 0 ? `−${fmtMoney(adjustments)}` : adjustments < 0 ? `+$${Math.abs(adjustments).toFixed(2)}` : '—'}</span>
                    <span id="st-net-due" class="text-lg font-bold text-gray-900"><strong>Net Due:</strong> ${fmtMoney(netPaid)}</span>
                </div>

                ${isEditable ? `
                <div class="grid grid-cols-1 md:grid-cols-3 gap-3 mb-3">
                    <div>
                        <label class="block text-xs font-medium text-gray-700 mb-1">Adjustment Amount</label>
                        <input type="number" step="0.01" id="st-adjustment" value="${adjustments !== 0 ? adjustments : ''}" placeholder="e.g. 6.15 (discount)"
                               oninput="window.salesTaxView.updateTaxPreview()"
                               class="w-full px-3 py-1.5 border border-gray-300 rounded-md text-sm">
                        <p class="text-xs text-gray-400 mt-0.5">Positive = discount (reduces net due)</p>
                    </div>
                    <div>
                        <label class="block text-xs font-medium text-gray-700 mb-1">Reason</label>
                        <input type="text" id="st-adjustment-reason" value="${escapeHtml(adjReason)}" placeholder="e.g. Timely filing discount"
                               class="w-full px-3 py-1.5 border border-gray-300 rounded-md text-sm">
                    </div>
                    <div>
                        <label class="block text-xs font-medium text-gray-700 mb-1">Paid Date (QBO)</label>
                        <input type="date" id="st-paid-date" value="${today}"
                               class="w-full px-3 py-1.5 border border-gray-300 rounded-md text-sm">
                    </div>
                </div>

                <div class="flex items-center justify-between border-t pt-3 mt-1">
                    <div id="st-je-lines">
                        <p class="text-sm"><strong>Summary:</strong></p>
                        <p class="text-xs text-gray-500">Tax Collected: ${fmtMoney(taxCollected)}</p>
                        ${adjustments > 0 ? `<p class="text-xs text-gray-500">Discount: −${fmtMoney(adjustments)}</p>` : ''}
                        ${adjustments < 0 ? `<p class="text-xs text-gray-500">Penalty: +$${Math.abs(adjustments).toFixed(2)}</p>` : ''}
                        <p class="text-xs text-gray-500 font-semibold">Net Due: ${fmtMoney(netPaid)}</p>
                    </div>
                    <div class="flex gap-2">
                        <button onclick="window.salesTaxView.saveTaxPeriodDraft()"
                                class="px-3 py-1.5 bg-gray-100 hover:bg-gray-200 text-gray-700 rounded-md text-sm font-medium border border-gray-300">
                            💾 Save Draft
                        </button>
                        <button onclick="window.salesTaxView.markPeriodPaid()"
                                class="px-4 py-2 bg-green-600 text-white rounded-md text-sm font-semibold hover:bg-green-700">
                            ✅ Mark as Paid
                        </button>
                    </div>
                </div>
                ` : periodStatus === 'booked' ? `
                <div class="border-t pt-3 mt-1">
                    <p class="text-sm text-green-700 font-semibold">✅ Booked — Journal Entry #${escapeHtml(existingPeriod.qbo_journal_entry_id)} on ${formatDate(existingPeriod.booked_at)}</p>
                </div>
                ` : `
                <div class="border-t pt-3 mt-1">
                    <p class="text-sm text-green-700 font-semibold">✅ Paid on ${formatDate(existingPeriod.booked_at)}</p>
                </div>
                `}
            </div>
        </div>`;

    detailEl.classList.remove('hidden');
    detailEl.scrollIntoView({ behavior: 'smooth' });
}

export function closeTaxPeriodDetail() {
    const el = document.getElementById('sales-tax-detail');
    if (el) el.classList.add('hidden');
    stEditingPeriodId = null;
}

export function updateTaxPreview() {
    if (!stCurrentTaxData) return;
    const adjInput = document.getElementById('st-adjustment');
    const adj = parseFloat(adjInput?.value) || 0;
    const taxCollected = stCurrentTaxData.taxCollected;
    const netPaid = taxCollected - adj;

    const adjDisplay = document.getElementById('st-adj-display');
    if (adjDisplay) {
        adjDisplay.className = adj !== 0 ? 'text-red-600' : '';
        adjDisplay.innerHTML = adj > 0
            ? `<strong>Adjustment:</strong> −${fmtMoney(adj)}`
            : adj < 0
                ? `<strong>Adjustment:</strong> +$${Math.abs(adj).toFixed(2)}`
                : `<strong>Adjustment:</strong> —`;
    }

    const netDue = document.getElementById('st-net-due');
    if (netDue) {
        netDue.innerHTML = `<strong>Net Due:</strong> ${fmtMoney(netPaid)}`;
    }

    const jeLines = document.getElementById('st-je-lines');
    if (jeLines) {
        jeLines.innerHTML = `
            <p class="text-sm"><strong>Summary:</strong></p>
            <p class="text-xs text-gray-500">Tax Collected: ${fmtMoney(taxCollected)}</p>
            ${adj > 0 ? `<p class="text-xs text-gray-500">Discount: −${fmtMoney(adj)}</p>` : ''}
            ${adj < 0 ? `<p class="text-xs text-gray-500">Penalty: +$${Math.abs(adj).toFixed(2)}</p>` : ''}
            <p class="text-xs text-gray-500 font-semibold">Net Due: ${fmtMoney(netPaid)}</p>`;
    }
}

export async function saveTaxPeriodDraft() {
    const adjAmount = parseFloat(document.getElementById('st-adjustment').value) || 0;
    const adjReason = document.getElementById('st-adjustment-reason').value.trim();

    if (!stCurrentTaxData) return alert('No tax data loaded.');

    try {
        const period = await window.API.accounting.upsertTaxPeriod({
            period_start: stCurrentTaxData.startDate,
            period_end: stCurrentTaxData.endDate,
            total_sales: stCurrentTaxData.totalSales,
            nontaxable_sales: stCurrentTaxData.nontaxableSales,
            taxable_sales: stCurrentTaxData.taxableSales,
            tax_collected: stCurrentTaxData.taxCollected,
            adjustment_amount: adjAmount,
            adjustment_reason: adjReason || null,
            net_paid: stCurrentTaxData.taxCollected - adjAmount,
            status: 'open'
        });
        await loadTaxPeriods();
        if (period?.period_start) {
            await openTaxPeriodDetail(period.period_start, period.period_end, period);
        }
    } catch (e) {
        alert('Failed to save: ' + e.message);
    }
}

export async function markPeriodPaid() {
    const adjAmount = parseFloat(document.getElementById('st-adjustment').value) || 0;
    const adjReason = document.getElementById('st-adjustment-reason').value.trim();
    const paidDate = document.getElementById('st-paid-date').value;
    if (!paidDate) return alert('Please select a paid date.');

    if (!stCurrentTaxData) return alert('No tax data loaded.');
    if (!stEditingPeriodId) return alert('Please save the period first (Save Draft).');

    const netPaid = stCurrentTaxData.taxCollected - adjAmount;

    if (!confirm(`Mark this period as paid?\n\nPaid Date: ${paidDate}\nTax Collected: $${stCurrentTaxData.taxCollected.toFixed(2)}\nAdjustment: $${adjAmount.toFixed(2)}\nNet Paid: $${netPaid.toFixed(2)}\n\nThis does NOT write to QBO — record the payment in QBO first.`)) return;

    try {
        await window.API.accounting.upsertTaxPeriod({
            period_start: stCurrentTaxData.startDate,
            period_end: stCurrentTaxData.endDate,
            total_sales: stCurrentTaxData.totalSales,
            nontaxable_sales: stCurrentTaxData.nontaxableSales,
            taxable_sales: stCurrentTaxData.taxableSales,
            tax_collected: stCurrentTaxData.taxCollected,
            adjustment_amount: adjAmount,
            adjustment_reason: adjReason || null,
            net_paid: netPaid,
            status: 'open'
        });
    } catch (e) {
        return alert('Failed to save period: ' + e.message);
    }

    try {
        await window.API.accounting.markTaxPaidExternal(stEditingPeriodId, paidDate);
        await loadTaxPeriods();
        const updated = stPeriods.find(p => p.id === stEditingPeriodId);
        if (updated) {
            await openTaxPeriodDetail(updated.period_start, updated.period_end, updated);
        }
    } catch (e) {
        alert('Failed: ' + e.message);
    }
}

function parseTaxDataFromReport(taxData) {
    if (!taxData?.Rows?.Row) return { totalSales: 0, nontaxableSales: 0, taxableSales: 0, taxCollected: 0 };
    const rows = Array.isArray(taxData.Rows.Row) ? taxData.Rows.Row : [];
    for (const row of rows) {
        if (row.type === 'Section' && row.Header?.ColData?.[0]?.value?.toLowerCase().includes('grand total')) {
            const cd = row.Summary?.ColData || [];
            return {
                totalSales: parseFloat(cd[1]?.value || '0') || 0,
                nontaxableSales: parseFloat(cd[2]?.value || '0') || 0,
                taxableSales: parseFloat(cd[3]?.value || '0') || 0,
                taxCollected: parseFloat(cd[4]?.value || '0') || 0
            };
        }
    }
    return { totalSales: 0, nontaxableSales: 0, taxableSales: 0, taxCollected: 0 };
}

/** numeric aus der DB (pg liefert NUMERIC als String) — sonst Fallback. */
function numOr(value, fallback) {
    if (value == null || value === '') return fallback;
    const n = parseFloat(value);
    return Number.isFinite(n) ? n : fallback;
}

/**
 * Kennzahlen einer gespeicherten Periode aus der DB-Zeile.
 * Fällt spaltenweise auf den Live-Wert zurück, falls die Spalte leer ist
 * (Altbestände ohne vollständigen Snapshot).
 */
function snapshotFromPeriod(period, fallback) {
    return {
        totalSales:      numOr(period.total_sales,      fallback.totalSales),
        nontaxableSales: numOr(period.nontaxable_sales, fallback.nontaxableSales),
        taxableSales:    numOr(period.taxable_sales,    fallback.taxableSales),
        taxCollected:    numOr(period.tax_collected,    fallback.taxCollected)
    };
}

/**
 * Ersetzt im live geladenen Report die GRAND-TOTAL-Zeile durch den gespeicherten
 * Snapshot, damit die Tabelle nicht einen anderen Gesamtbetrag zeigt als die
 * Summary-Leiste darunter. Die Distrikt-Zeilen bleiben unberührt (Aufschlüsselung).
 * Arbeitet auf einer flachen Kopie — taxData selbst wird nicht mutiert.
 */
function withSnapshotGrandTotal(taxData, snapshot) {
    if (!taxData?.Rows?.Row || !Array.isArray(taxData.Rows.Row)) return taxData;
    const rows = taxData.Rows.Row.map(row => {
        const label = row?.Header?.ColData?.[0]?.value;
        if (row?.type !== 'Section' || !label || !label.toLowerCase().includes('grand total')) return row;
        const cd = row.Summary?.ColData || [];
        return {
            ...row,
            Summary: {
                ColData: [
                    { value: cd[0]?.value || 'Total' },
                    { value: snapshot.totalSales.toFixed(2) },
                    { value: snapshot.nontaxableSales.toFixed(2) },
                    { value: snapshot.taxableSales.toFixed(2) },
                    { value: snapshot.taxCollected.toFixed(2) },
                    { value: cd[5]?.value || '' }
                ]
            }
        };
    });
    return { ...taxData, Rows: { ...taxData.Rows, Row: rows } };
}

// ────────────────────────────────────────────────────────────────────
// Init / Public Entry Point
// ────────────────────────────────────────────────────────────────────

export function renderSalesTaxView() {
    injectSalesTaxSection();
    loadTaxPeriods();
}

window.salesTaxView = {
    renderSalesTaxView,
    injectSalesTaxSection,
    loadTaxPeriods,
    openNewTaxPeriod,
    openTaxPeriod,
    closeTaxPeriodDetail,
    updateTaxPreview,
    saveTaxPeriodDraft,
    markPeriodPaid
};