import React, { useState, useMemo, useCallback, useRef } from 'react';
import * as XLSX from 'xlsx';
import { ExcelFilter } from './ExcelFilter';
import { ColumnFilterCondition } from '../types';
import { AmazonSmileIcon } from './Icons';

const MONTHS = ['January','February','March','April','May','June','July','August','September','October','November','December'];
const MONTHS_SHORT = ['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'];

// Column indices of "Budget Units" in Budget 26 file (one per month, every 8 columns starting at 8)
const BUDGET_UNITS_COLS = [8, 16, 24, 32, 40, 48, 56, 64, 72, 80, 88, 96];

interface SellInRow {
  sku: string;
  description: string;
  actualUnits: number;
  sellInBudget: number;
}

interface BudgetRow {
  sku: string;
  description: string;
  monthlyBudget: number[]; // 12 values Jan–Dec
}

interface ComparisonRow {
  sku: string;
  description: string;
  asins: string[];
  title: string;
  actualUnits: number;
  periodForecast: number;
  budgetYearTotal: number;
  budgetDiscrepancy: boolean;
  pctPeriod: number;
  pctAnnual: number;
  vendorStockEU: number;
  vendorStockUK: number;
}

function parseSellIn(buffer: ArrayBuffer): Map<string, SellInRow> {
  const wb = XLSX.read(buffer, { type: 'array' });
  const ws = wb.Sheets['Export'];
  if (!ws) throw new Error('Hoja "Export" no encontrada en fichero Sell in');
  const rows = XLSX.utils.sheet_to_json<any[]>(ws, { header: 1, defval: '' });
  const result = new Map<string, SellInRow>();
  for (let i = 1; i < rows.length; i++) {
    const row = rows[i];
    const rawArticle = String(row[0] ?? '').trim();
    if (!rawArticle) continue;
    const sku = rawArticle.slice(0, 5);
    if (!/^\d{5}$/.test(sku)) continue;
    result.set(sku, {
      sku,
      description: rawArticle.slice(6).trim(),
      actualUnits: Number(row[8]) || 0,
      sellInBudget: Number(row[10]) || 0,
    });
  }
  return result;
}

function parseBudget(buffer: ArrayBuffer): Map<string, BudgetRow> {
  const wb = XLSX.read(buffer, { type: 'array' });
  const ws = wb.Sheets['Export'];
  if (!ws) throw new Error('Hoja "Export" no encontrada en fichero Budget');
  const rows = XLSX.utils.sheet_to_json<any[]>(ws, { header: 1, defval: '' });
  const result = new Map<string, BudgetRow>();
  // Row 0 = months, Row 1 = sub-fields, data from row 2
  for (let i = 2; i < rows.length; i++) {
    const row = rows[i];
    const rawArticle = String(row[0] ?? '').trim();
    if (!rawArticle) continue;
    const sku = rawArticle.slice(0, 5);
    if (!/^\d{5}$/.test(sku)) continue;
    result.set(sku, {
      sku,
      description: rawArticle.slice(6).trim(),
      monthlyBudget: BUDGET_UNITS_COLS.map(c => Number(row[c]) || 0),
    });
  }
  return result;
}

const getPctColor = (pct: number) => {
  if (pct <= 0) return 'text-slate-500';
  if (pct >= 100) return 'text-emerald-400';
  if (pct >= 80) return 'text-amber-400';
  return 'text-rose-400';
};

const getPctBg = (pct: number) => {
  if (pct <= 0) return 'bg-slate-700';
  if (pct >= 100) return 'bg-emerald-500';
  if (pct >= 80) return 'bg-amber-400';
  return 'bg-rose-500';
};

// ── Sub-components ──────────────────────────────────────────────────────────

const DropZone: React.FC<{
  label: string;
  subtitle: string;
  loaded: boolean;
  fileName: string;
  count?: number;
  onDrop: (f: File) => void;
  onClick: () => void;
}> = ({ label, subtitle, loaded, fileName, count, onDrop, onClick }) => (
  <div
    className={`border-2 border-dashed rounded-xl p-6 flex flex-col items-center justify-center gap-3 cursor-pointer transition-all min-h-[140px] ${
      loaded
        ? 'border-emerald-500/50 bg-emerald-500/5'
        : 'border-slate-700 hover:border-indigo-500/50 hover:bg-indigo-500/5'
    }`}
    onClick={onClick}
    onDragOver={e => e.preventDefault()}
    onDrop={e => { e.preventDefault(); const f = e.dataTransfer.files[0]; if (f) onDrop(f); }}
  >
    <div className={`text-3xl ${loaded ? 'text-emerald-400' : 'text-slate-600'}`}>
      {loaded ? '✓' : '📊'}
    </div>
    <div className="text-center">
      <div className="text-sm font-black text-white">{label}</div>
      <div className="text-xs text-slate-500 mt-1">{subtitle}</div>
      {loaded
        ? <div className="text-xs text-emerald-400 mt-2">{fileName} — {count} SKUs cargados</div>
        : <div className="text-[10px] text-slate-600 mt-2 uppercase tracking-wider">Clic o arrastra aquí</div>
      }
    </div>
  </div>
);

const ComparisonTableRow: React.FC<{ row: ComparisonRow }> = React.memo(({ row }) => {
  const barWidth = Math.min(100, row.pctPeriod);
  return (
    <tr className="hover:bg-indigo-500/5 transition-colors border-b border-slate-800/50 last:border-0">
      <td className="px-4 py-3 whitespace-nowrap">
        <span className="text-xs font-black text-indigo-400 tracking-tighter">{row.sku}</span>
      </td>
      <td className="px-4 py-3 max-w-[280px]">
        <span className="text-sm text-slate-200 line-clamp-1" title={row.description}>
          {row.description}
        </span>
      </td>
      <td className="px-4 py-3 whitespace-nowrap">
        <div className="flex flex-col gap-1">
          {row.vendorStockEU > 0 ? (
            <div
              className="inline-flex items-center gap-1.5 px-2 py-1 rounded bg-gradient-to-br from-indigo-500 to-blue-600 text-white border border-indigo-400/50 shadow-lg text-[10px] font-bold w-fit"
              title={`Stock Amazon Vendor EU: ${row.vendorStockEU.toLocaleString('de-DE')}`}
            >
              <AmazonSmileIcon className="w-3 h-3 shrink-0" />
              <span className="text-[7px] font-black uppercase opacity-80">EU</span>
              <span>{row.vendorStockEU.toLocaleString('de-DE')}</span>
            </div>
          ) : (
            <div className="inline-flex items-center gap-1.5 px-2 py-1 rounded border text-[10px] font-bold bg-slate-800/50 text-slate-500 border-slate-700/50 w-fit">
              <span className="text-[7px] font-black uppercase">EU</span>
              <span>—</span>
            </div>
          )}
          {row.vendorStockUK > 0 ? (
            <div
              className="inline-flex items-center gap-1.5 px-2 py-1 rounded bg-gradient-to-br from-rose-500 to-red-600 text-white border border-rose-400/50 shadow-lg text-[10px] font-bold w-fit"
              title={`Stock Amazon Vendor UK: ${row.vendorStockUK.toLocaleString('de-DE')}`}
            >
              <AmazonSmileIcon className="w-3 h-3 shrink-0" />
              <span className="text-[7px] font-black uppercase opacity-80">UK</span>
              <span>{row.vendorStockUK.toLocaleString('de-DE')}</span>
            </div>
          ) : (
            <div className="inline-flex items-center gap-1.5 px-2 py-1 rounded border text-[10px] font-bold bg-slate-800/50 text-slate-500 border-slate-700/50 w-fit">
              <span className="text-[7px] font-black uppercase">UK</span>
              <span>—</span>
            </div>
          )}
        </div>
      </td>
      <td className="px-4 py-3 text-right whitespace-nowrap">
        <span className="text-sm font-black text-emerald-400">
          {row.actualUnits.toLocaleString('de-DE')}
        </span>
      </td>
      <td className="px-4 py-3 text-right whitespace-nowrap">
        <span className="text-sm font-bold text-slate-300">
          {row.periodForecast.toLocaleString('de-DE')}
        </span>
      </td>
      <td className="px-4 py-3 text-right whitespace-nowrap">
        <div className="flex flex-col items-end gap-0.5">
          <span className="text-sm font-bold text-slate-400">
            {row.budgetYearTotal.toLocaleString('de-DE')}
          </span>
          {row.budgetDiscrepancy && (
            <span className="text-[9px] font-black text-amber-400 uppercase">⚠ discrepancia</span>
          )}
        </div>
      </td>
      <td className="px-4 py-3">
        <div className="flex flex-col items-center gap-1">
          <span className={`text-sm font-black ${getPctColor(row.pctPeriod)}`}>
            {row.periodForecast > 0 ? `${row.pctPeriod.toFixed(1)}%` : '—'}
          </span>
          {row.periodForecast > 0 && (
            <div className="h-1.5 w-full bg-slate-800 rounded-full overflow-hidden max-w-[100px]">
              <div
                className={`h-full rounded-full ${getPctBg(row.pctPeriod)}`}
                style={{ width: `${barWidth}%` }}
              />
            </div>
          )}
        </div>
      </td>
      <td className="px-4 py-3 text-center whitespace-nowrap">
        <span className={`text-sm font-bold ${getPctColor(row.pctAnnual)}`}>
          {row.budgetYearTotal > 0 ? `${row.pctAnnual.toFixed(1)}%` : '—'}
        </span>
      </td>
    </tr>
  );
});

// ── Main Component ───────────────────────────────────────────────────────────

interface ForecastViewProps {
  asinMetadata?: Map<string, { sku: string; title: string; line: string }>;
  vendorStockMap?: Map<string, { eu: number; uk: number }>;
}

const ForecastView: React.FC<ForecastViewProps> = ({ asinMetadata, vendorStockMap }) => {
  const [sellInData, setSellInData] = useState<Map<string, SellInRow> | null>(null);
  const [budgetData, setBudgetData] = useState<Map<string, BudgetRow> | null>(null);
  const [sellInFileName, setSellInFileName] = useState('');
  const [budgetFileName, setBudgetFileName] = useState('');
  // Default cutoff: May (index 4) — adjust as needed
  const [cutoffMonth, setCutoffMonth] = useState<number>(4);
  const [error, setError] = useState<string | null>(null);
  const [searchQuery, setSearchQuery] = useState('');
  const [columnFilters, setColumnFilters] = useState<Record<string, ColumnFilterCondition>>({});

  const sellInInputRef = useRef<HTMLInputElement>(null);
  const budgetInputRef = useRef<HTMLInputElement>(null);

  const loadFile = useCallback((file: File, type: 'sellin' | 'budget') => {
    setError(null);
    const reader = new FileReader();
    reader.onload = (e) => {
      try {
        const buf = e.target!.result as ArrayBuffer;
        if (type === 'sellin') {
          const data = parseSellIn(buf);
          setSellInData(data);
          setSellInFileName(file.name);
        } else {
          const data = parseBudget(buf);
          setBudgetData(data);
          setBudgetFileName(file.name);
        }
      } catch (err: any) {
        setError(`Error en ${type === 'sellin' ? 'Sell in' : 'Budget'}: ${err.message}`);
      }
    };
    reader.readAsArrayBuffer(file);
  }, []);

  const skuMetadata = useMemo(() => {
    const map = new Map<string, { asins: string[]; title: string }>();
    if (!asinMetadata) return map;
    asinMetadata.forEach((meta, asin) => {
      const existing = map.get(meta.sku);
      if (existing) {
        existing.asins.push(asin);
        if (meta.title && meta.title.length > (existing.title?.length || 0)) {
          existing.title = meta.title;
        }
      } else {
        map.set(meta.sku, { asins: [asin], title: meta.title || '' });
      }
    });
    return map;
  }, [asinMetadata]);

  const comparisonRows = useMemo((): ComparisonRow[] => {
    if (!budgetData) return [];
    const rows: ComparisonRow[] = [];
    budgetData.forEach((budgetRow) => {
      const sellIn = sellInData?.get(budgetRow.sku);
      const actualUnits = sellIn?.actualUnits ?? 0;
      const sellInBudget = sellIn?.sellInBudget ?? 0;
      const periodForecast = budgetRow.monthlyBudget
        .slice(0, cutoffMonth + 1)
        .reduce((a, b) => a + b, 0);
      const budgetYearTotal = budgetRow.monthlyBudget.reduce((a, b) => a + b, 0);
      const budgetDiscrepancy = sellIn != null && Math.abs(budgetYearTotal - sellInBudget) > 1;
      const pctPeriod = periodForecast > 0 ? (actualUnits / periodForecast) * 100 : 0;
      const pctAnnual = budgetYearTotal > 0 ? (actualUnits / budgetYearTotal) * 100 : 0;
      const meta = skuMetadata.get(budgetRow.sku);
      const asins = meta?.asins ?? [];
      const vendorStockEU = asins.reduce((sum, asin) => {
        return sum + (vendorStockMap?.get(asin.trim().toUpperCase())?.eu ?? 0);
      }, 0);
      const vendorStockUK = asins.reduce((sum, asin) => {
        return sum + (vendorStockMap?.get(asin.trim().toUpperCase())?.uk ?? 0);
      }, 0);
      rows.push({
        sku: budgetRow.sku,
        description: budgetRow.description,
        asins,
        title: meta?.title ?? '',
        actualUnits,
        periodForecast,
        budgetYearTotal,
        budgetDiscrepancy,
        pctPeriod,
        pctAnnual,
        vendorStockEU,
        vendorStockUK,
      });
    });
    return rows;
  }, [budgetData, sellInData, cutoffMonth, skuMetadata, vendorStockMap]);

  const passesTextFilter = useCallback((value: string, filter?: ColumnFilterCondition): boolean => {
    if (!filter) return true;
    if (filter.selectedValues && filter.selectedValues.length > 0) {
      if (!filter.selectedValues.includes(value)) return false;
    }
    if (filter.textFilter) {
      const { operator, value: filterVal } = filter.textFilter;
      if (!filterVal) return true;
      const v = value.toLowerCase();
      const fv = filterVal.toLowerCase();
      switch (operator) {
        case 'equals': return v === fv;
        case 'notEquals': return v !== fv;
        case 'contains': return v.includes(fv);
        case 'notContains': return !v.includes(fv);
        case 'startsWith': return v.startsWith(fv);
        case 'notStartsWith': return !v.startsWith(fv);
        case 'endsWith': return v.endsWith(fv);
        case 'notEndsWith': return !v.endsWith(fv);
        default: return true;
      }
    }
    return true;
  }, []);

  const passesNumericFilter = useCallback((value: number, filter?: ColumnFilterCondition): boolean => {
    if (!filter) return true;
    if (filter.textFilter) {
      const { operator, value: filterVal } = filter.textFilter;
      const fv = parseFloat(filterVal);
      if (isNaN(fv)) return true;
      switch (operator) {
        case 'equals': return value === fv;
        case 'notEquals': return value !== fv;
        case 'gt': return value > fv;
        case 'gte': return value >= fv;
        case 'lt': return value < fv;
        case 'lte': return value <= fv;
        default: return true;
      }
    }
    return true;
  }, []);

  const filteredRows = useMemo(() => {
    let rows = comparisonRows;

    // Apply column filters
    const hasColumnFilter = Object.keys(columnFilters).some(k => {
      const f = columnFilters[k];
      return f?.selectedValues || f?.textFilter;
    });
    if (hasColumnFilter) {
      rows = rows.filter(row => {
        return Object.entries(columnFilters).every(([key, filter]) => {
          if (!filter) return true;
          if (key === 'sku') return passesTextFilter(row.sku, filter);
          if (key === 'description') return passesTextFilter(row.description, filter);
          if (key === 'actualUnits') return passesNumericFilter(row.actualUnits, filter);
          if (key === 'periodForecast') return passesNumericFilter(row.periodForecast, filter);
          if (key === 'budgetYearTotal') return passesNumericFilter(row.budgetYearTotal, filter);
          if (key === 'pctPeriod') return passesNumericFilter(row.pctPeriod, filter);
          if (key === 'pctAnnual') return passesNumericFilter(row.pctAnnual, filter);
          return true;
        });
      });
    }

    // Apply search filter
    if (searchQuery.trim()) {
      const terms = searchQuery
        .split(/[\s,;|\n]+/)
        .map(t => t.trim().toLowerCase())
        .filter(Boolean);
      if (terms.length > 0) {
        rows = rows.filter(row => {
          return terms.some(term => {
            if (row.sku.toLowerCase().includes(term)) return true;
            if (row.description.toLowerCase().includes(term)) return true;
            if (row.title.toLowerCase().includes(term)) return true;
            if (row.asins.some(asin => asin.toLowerCase().includes(term))) return true;
            return false;
          });
        });
      }
    }

    // Apply column sort (first column with sort wins)
    const sortEntry = Object.entries(columnFilters).find(([_, f]) => f?.sort);
    if (sortEntry) {
      const [sortKey, sortFilter] = sortEntry;
      const dir = sortFilter.sort === 'desc' ? -1 : 1;
      rows = [...rows].sort((a, b) => {
        let va: any, vb: any;
        switch (sortKey) {
          case 'sku': va = a.sku; vb = b.sku; break;
          case 'description': va = a.description; vb = b.description; break;
          case 'actualUnits': va = a.actualUnits; vb = b.actualUnits; break;
          case 'periodForecast': va = a.periodForecast; vb = b.periodForecast; break;
          case 'budgetYearTotal': va = a.budgetYearTotal; vb = b.budgetYearTotal; break;
          case 'pctPeriod': va = a.pctPeriod; vb = b.pctPeriod; break;
          case 'pctAnnual': va = a.pctAnnual; vb = b.pctAnnual; break;
          default: return 0;
        }
        if (typeof va === 'string') return dir * va.localeCompare(vb);
        return dir * ((va as number) - (vb as number));
      });
    }

    return rows;
  }, [comparisonRows, searchQuery, columnFilters, passesTextFilter, passesNumericFilter]);

  const kpis = useMemo(() => {
    const totalActual = comparisonRows.reduce((s, r) => s + r.actualUnits, 0);
    const totalPeriodForecast = comparisonRows.reduce((s, r) => s + r.periodForecast, 0);
    const totalBudgetYear = comparisonRows.reduce((s, r) => s + r.budgetYearTotal, 0);
    const withForecast = comparisonRows.filter(r => r.periodForecast > 0);
    const below80 = withForecast.filter(r => r.pctPeriod < 80).length;
    const pctOverall = totalPeriodForecast > 0 ? (totalActual / totalPeriodForecast) * 100 : 0;
    return { totalActual, totalPeriodForecast, totalBudgetYear, below80, pctOverall, withForecastCount: withForecast.length };
  }, [comparisonRows]);

  const handleColumnFilterChange = useCallback((columnKey: string, condition: ColumnFilterCondition | undefined) => {
    setColumnFilters(prev => {
      const next = { ...prev };
      if (condition) {
        next[columnKey] = condition;
      } else {
        delete next[columnKey];
      }
      return next;
    });
  }, []);

  const columnUniqueValues = useMemo(() => {
    if (comparisonRows.length === 0) return { sku: [], description: [] } as Record<string, string[]>;
    return {
      sku: Array.from(new Set(comparisonRows.map(r => r.sku))).sort() as string[],
      description: Array.from(new Set(comparisonRows.map(r => r.description))).sort() as string[],
      actualUnits: Array.from(new Set(comparisonRows.map(r => String(r.actualUnits)))).sort((a, b) => Number(a) - Number(b)) as string[],
      periodForecast: Array.from(new Set(comparisonRows.map(r => String(r.periodForecast)))).sort((a, b) => Number(a) - Number(b)) as string[],
      budgetYearTotal: Array.from(new Set(comparisonRows.map(r => String(r.budgetYearTotal)))).sort((a, b) => Number(a) - Number(b)) as string[],
      pctPeriod: Array.from(new Set(comparisonRows.map(r => r.periodForecast > 0 ? r.pctPeriod.toFixed(1) + '%' : '—'))).sort() as string[],
      pctAnnual: Array.from(new Set(comparisonRows.map(r => r.budgetYearTotal > 0 ? r.pctAnnual.toFixed(1) + '%' : '—'))).sort() as string[],
    };
  }, [comparisonRows]);

  const handleExport = useCallback(() => {
    const data = comparisonRows.map(r => ({
      SKU: r.sku,
      Descripción: r.description,
      'Real Sell-in (Uds)': r.actualUnits,
      [`Forecast Período Jan–${MONTHS_SHORT[cutoffMonth]}`]: r.periodForecast,
      'Budget Total Año': r.budgetYearTotal,
      'Discrepancia Budget': r.budgetDiscrepancy ? 'SÍ' : '',
      '% Cumpl. Período': r.periodForecast > 0 ? r.pctPeriod.toFixed(1) + '%' : '—',
      '% Budget Consumido': r.budgetYearTotal > 0 ? r.pctAnnual.toFixed(1) + '%' : '—',
    }));
    const ws = XLSX.utils.json_to_sheet(data);
    const wb = XLSX.utils.book_new();
    XLSX.utils.book_append_sheet(wb, ws, 'Sell-in vs Budget');
    XLSX.writeFile(wb, `SellIn_vs_Budget_${new Date().toISOString().slice(0, 10)}.xlsx`);
  }, [comparisonRows, cutoffMonth]);

  const isReady = budgetData !== null;

  return (
    <div className="flex flex-col gap-4 md:gap-6 animate-fade-in p-3 md:p-6 h-full overflow-hidden">
      {/* Hidden file inputs — always in DOM */}
      <input
        ref={sellInInputRef}
        type="file"
        accept=".xlsx,.xls"
        className="hidden"
        onChange={e => e.target.files?.[0] && loadFile(e.target.files[0], 'sellin')}
        onClick={e => { (e.target as HTMLInputElement).value = ''; }}
      />
      <input
        ref={budgetInputRef}
        type="file"
        accept=".xlsx,.xls"
        className="hidden"
        onChange={e => e.target.files?.[0] && loadFile(e.target.files[0], 'budget')}
        onClick={e => { (e.target as HTMLInputElement).value = ''; }}
      />

      {/* ── Upload UI (shown until budget is loaded) ── */}
      {!isReady && (
        <div className="bg-slate-900 border border-white/5 rounded-2xl p-6 flex flex-col gap-6">
          <h2 className="text-sm font-black text-white uppercase tracking-widest">
            Sell-in vs Budget 2026 — Carga los ficheros
          </h2>
          <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
            <DropZone
              label="Sell in (*.xlsx)"
              subtitle="Col A: Raw Article · Col I: Sell-in Units Year · Col K: Budget Units"
              loaded={sellInData !== null}
              fileName={sellInFileName}
              count={sellInData?.size}
              onDrop={f => loadFile(f, 'sellin')}
              onClick={() => sellInInputRef.current?.click()}
            />
            <DropZone
              label="Budget 26 (*.xlsx)"
              subtitle="Hoja Export · Fila 1: meses · Fila 2: sub-campos · Datos desde fila 3"
              loaded={budgetData !== null}
              fileName={budgetFileName}
              count={budgetData?.size}
              onDrop={f => loadFile(f, 'budget')}
              onClick={() => budgetInputRef.current?.click()}
            />
          </div>
          {error && (
            <div className="p-3 bg-rose-500/10 border border-rose-500/20 rounded-lg text-xs text-rose-400">
              {error}
            </div>
          )}
        </div>
      )}

      {/* ── Compact toolbar (shown when budget is loaded) ── */}
      {isReady && (
        <div className="flex flex-wrap items-center gap-3 shrink-0">
          <button
            onClick={() => sellInInputRef.current?.click()}
            className={`flex items-center gap-2 px-3 py-1.5 rounded-lg border text-[10px] font-black uppercase tracking-wider transition-all ${
              sellInData
                ? 'border-emerald-500/30 bg-emerald-500/10 text-emerald-400'
                : 'border-slate-600 text-slate-400 hover:border-indigo-500/50'
            }`}
          >
            {sellInData ? '✓' : '+'} Sell In{sellInData ? ` (${sellInData.size} SKUs)` : ' — sin cargar'}
          </button>
          <button
            onClick={() => budgetInputRef.current?.click()}
            className="flex items-center gap-2 px-3 py-1.5 rounded-lg border text-[10px] font-black uppercase tracking-wider border-emerald-500/30 bg-emerald-500/10 text-emerald-400"
          >
            ✓ Budget 26 ({budgetData!.size} SKUs)
          </button>
          {error && <span className="text-xs text-rose-400">{error}</span>}

          <div className="flex items-center gap-2 ml-auto">
            <span className="text-[10px] font-black text-slate-400 uppercase tracking-wider">Período hasta</span>
            <select
              value={cutoffMonth}
              onChange={e => setCutoffMonth(Number(e.target.value))}
              className="bg-slate-800 border border-white/10 rounded-lg px-3 py-1.5 text-sm text-white focus:outline-none focus:ring-1 focus:ring-indigo-500"
            >
              {MONTHS.map((m, i) => <option key={m} value={i}>{m}</option>)}
            </select>
          </div>
          <button
            onClick={handleExport}
            className="px-3 py-1.5 bg-slate-800 hover:bg-slate-700 text-white rounded-lg border border-white/5 transition-all text-xs font-black uppercase tracking-wider"
            title="Exportar a Excel"
          >
            ↓ Excel
          </button>
        </div>
      )}

      {/* ── KPI Cards ── */}
      {isReady && (
        <div className="grid grid-cols-2 md:grid-cols-4 gap-3 shrink-0">
          <div className="bg-slate-900 border border-white/5 p-4 rounded-xl shadow-lg">
            <div className="text-[10px] font-black text-emerald-400 uppercase tracking-widest mb-1">Total Real</div>
            <div className="text-2xl font-black text-emerald-400">{kpis.totalActual.toLocaleString('de-DE')}</div>
            <div className="text-[9px] text-slate-500 mt-1 uppercase">Unidades vendidas a Amazon</div>
          </div>
          <div className="bg-slate-900 border border-white/5 p-4 rounded-xl shadow-lg">
            <div className="text-[10px] font-black text-indigo-400 uppercase tracking-widest mb-1">
              Forecast Jan–{MONTHS_SHORT[cutoffMonth]}
            </div>
            <div className="text-2xl font-black text-white">{kpis.totalPeriodForecast.toLocaleString('de-DE')}</div>
            <div className={`text-[11px] font-black mt-1 ${getPctColor(kpis.pctOverall)}`}>
              {kpis.pctOverall.toFixed(1)}% cumplimiento global
            </div>
          </div>
          <div className="bg-slate-900 border border-white/5 p-4 rounded-xl shadow-lg">
            <div className="text-[10px] font-black text-slate-400 uppercase tracking-widest mb-1">Budget Total Año</div>
            <div className="text-2xl font-black text-white">{kpis.totalBudgetYear.toLocaleString('de-DE')}</div>
            <div className="text-[9px] text-slate-500 mt-1 uppercase">12 meses acumulados</div>
          </div>
          <div className="bg-slate-900 border border-white/5 p-4 rounded-xl shadow-lg">
            <div className="text-[10px] font-black text-rose-400 uppercase tracking-widest mb-1">SKUs &lt; 80% Forecast</div>
            <div className="text-2xl font-black text-rose-400">{kpis.below80}</div>
            <div className="text-[9px] text-slate-500 mt-1 uppercase">
              de {kpis.withForecastCount} con forecast período
            </div>
          </div>
        </div>
      )}

      {/* ── Comparison Table ── */}
      {isReady && (
        <div className="bg-slate-900 border border-white/10 rounded-2xl overflow-hidden shadow-2xl flex-1 flex flex-col min-h-0">
          <div className="sticky top-0 z-20 bg-slate-950 border-b border-slate-800/50">
            <div className="px-4 py-2">
              <input
                type="text"
                value={searchQuery}
                onChange={e => setSearchQuery(e.target.value)}
                placeholder="Buscar por SKU, ASIN, o título... (separar varios con espacio o coma)"
                className="w-full bg-slate-800 border border-slate-700 rounded-lg px-3 py-1.5 text-sm text-white placeholder-slate-500 focus:outline-none focus:ring-1 focus:ring-indigo-500"
              />
            </div>
          </div>
          <div className="flex-1 overflow-auto min-h-0 custom-scrollbar">
            <table className="w-full text-left border-collapse text-xs md:text-sm">
              <thead className="sticky top-0 z-20 bg-slate-950 shadow-sm">
                <tr className="text-[10px] font-black text-slate-300 uppercase tracking-wider">
                  <th className="px-4 py-3 text-left w-[7%]">
                    <div className="flex items-center gap-0.5">
                      <span>SKU</span>
                      <ExcelFilter
                        columnKey="sku"
                        title="SKU"
                        uniqueValues={columnUniqueValues.sku}
                        currentFilter={columnFilters.sku}
                        onFilterChange={handleColumnFilterChange}
                      />
                    </div>
                  </th>
                  <th className="px-4 py-3 text-left">
                    <div className="flex items-center gap-0.5">
                      <span>Descripción</span>
                      <ExcelFilter
                        columnKey="description"
                        title="Descripción"
                        uniqueValues={columnUniqueValues.description}
                        currentFilter={columnFilters.description}
                        onFilterChange={handleColumnFilterChange}
                      />
                    </div>
                  </th>
                  <th className="px-4 py-3 text-left w-[12%]">
                    <div className="flex items-center gap-0.5">
                      <span>Stock</span>
                    </div>
                  </th>
                  <th className="px-4 py-3 text-right w-[11%]">
                    <div className="flex items-center justify-end gap-0.5">
                      <ExcelFilter
                        columnKey="actualUnits"
                        title="Real Sell-in"
                        uniqueValues={columnUniqueValues.actualUnits}
                        currentFilter={columnFilters.actualUnits}
                        onFilterChange={handleColumnFilterChange}
                      />
                      <span>Real Sell-in</span>
                    </div>
                  </th>
                  <th className="px-4 py-3 text-right w-[13%]">
                    <div className="flex items-center justify-end gap-0.5">
                      <ExcelFilter
                        columnKey="periodForecast"
                        title="Forecast Período"
                        uniqueValues={columnUniqueValues.periodForecast}
                        currentFilter={columnFilters.periodForecast}
                        onFilterChange={handleColumnFilterChange}
                      />
                      <div className="text-right">
                        <div>Forecast Período</div>
                        <div className="text-[9px] font-normal normal-case text-slate-600 mt-0.5">
                          Jan–{MONTHS_SHORT[cutoffMonth]}
                        </div>
                      </div>
                    </div>
                  </th>
                  <th className="px-4 py-3 text-right w-[11%]">
                    <div className="flex items-center justify-end gap-0.5">
                      <ExcelFilter
                        columnKey="budgetYearTotal"
                        title="Budget Año"
                        uniqueValues={columnUniqueValues.budgetYearTotal}
                        currentFilter={columnFilters.budgetYearTotal}
                        onFilterChange={handleColumnFilterChange}
                      />
                      <div className="text-right">
                        <div>Budget Año</div>
                        <div className="text-[9px] font-normal normal-case text-slate-600 mt-0.5">12 meses</div>
                      </div>
                    </div>
                  </th>
                  <th className="px-4 py-3 text-center w-[15%]">
                    <div className="flex items-center justify-center gap-0.5">
                      <ExcelFilter
                        columnKey="pctPeriod"
                        title="% Cumpl. Período"
                        uniqueValues={columnUniqueValues.pctPeriod}
                        currentFilter={columnFilters.pctPeriod}
                        onFilterChange={handleColumnFilterChange}
                      />
                      <div className="text-center">
                        <div>% Cumpl. Período</div>
                        <div className="text-[9px] font-normal normal-case text-slate-600 mt-0.5">real / forecast período</div>
                      </div>
                    </div>
                  </th>
                  <th className="px-4 py-3 text-center w-[13%]">
                    <div className="flex items-center justify-center gap-0.5">
                      <ExcelFilter
                        columnKey="pctAnnual"
                        title="% Budget Consumido"
                        uniqueValues={columnUniqueValues.pctAnnual}
                        currentFilter={columnFilters.pctAnnual}
                        onFilterChange={handleColumnFilterChange}
                      />
                      <div className="text-center">
                        <div>% Budget Consumido</div>
                        <div className="text-[9px] font-normal normal-case text-slate-600 mt-0.5">real / budget año</div>
                      </div>
                    </div>
                  </th>
                </tr>
              </thead>
              <tbody className="divide-y divide-slate-800/50">
                {filteredRows.map(row => (
                  <ComparisonTableRow key={row.sku} row={row} />
                ))}
              </tbody>
              {filteredRows.length === 0 && (
                <div className="flex items-center justify-center py-20 text-slate-500 text-sm">
                  {searchQuery.trim() ? 'No se encontraron productos con esos criterios' : 'Sin datos de comparación'}
                </div>
              )}
              {searchQuery.trim() && filteredRows.length > 0 && (
                <div className="sticky bottom-0 bg-slate-950 border-t border-slate-800/50 px-4 py-1.5 text-[10px] text-slate-500 text-right">
                  {filteredRows.length} de {comparisonRows.length} SKUs
                </div>
              )}
            </table>
          </div>
        </div>
      )}
    </div>
  );
};

export default ForecastView;