const sizeOrder = ['2', '4', '6', '8', '10', '12', '14', '16', 'PP', 'P', 'M', 'G', 'GG', 'XG', 'G1', 'G2', 'G3', 'G4', 'G5'];
const sizeSet = new Set(sizeOrder);
const knownColors = [
  'BRANCO + PRETO',
  'CINZA/PRETO',
  'VERDE BANDEIRA',
  'VERDE MILITAR',
  'AZUL MARINHO',
  'CINZA GRAFITE',
  'AMARELO',
  'BRANCO',
  'GRAFITE',
  'MARINHO',
  'VERMELHO',
  'BORDO',
  'CAFE',
  'CAQUI',
  'CHUMBO',
  'CINZA',
  'MARROM',
  'PEROLA',
  'PRETO',
  'ROYAL',
  'ROSA',
  'ROXO',
  'VERDE',
  'AZUL',
  'BEGE'
].sort((a, b) => b.length - a.length);

export const normalizeProductText = (value: string) => value.replace(/\s+/g, ' ').trim();

const normalizeForMatch = (value: string) => normalizeProductText(value)
  .normalize('NFD')
  .replace(/\p{Diacritic}/gu, '')
  .toUpperCase();

const escapeRegex = (value: string) => value.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');

const toFlexiblePattern = (value: string) => escapeRegex(value).replace(/\s+/g, '\\s+');

const findLeadingColor = (value: string) => {
  const normalizedValue = normalizeForMatch(value);
  return knownColors.find(color => normalizedValue === color || normalizedValue.startsWith(`${color} `)) || '';
};

const findTrailingColor = (value: string) => {
  const normalizedValue = normalizeForMatch(value);
  return knownColors.find(color => normalizedValue === color || normalizedValue.endsWith(` ${color}`) || normalizedValue.endsWith(`- ${color}`)) || '';
};

export const encodeProductGroupKey = (value: string) => {
  const normalizedValue = normalizeProductText(value);
  const bytes = new TextEncoder().encode(normalizedValue);
  const binary = Array.from(bytes, byte => String.fromCharCode(byte)).join('');

  return btoa(binary).replace(/\+/g, '-').replace(/\//g, '_').replace(/=+$/g, '');
};

export const decodeProductGroupKey = (value: string) => {
  const base64 = value.replace(/-/g, '+').replace(/_/g, '/');
  const paddedBase64 = base64.padEnd(Math.ceil(base64.length / 4) * 4, '=');
  const binary = atob(paddedBase64);
  const bytes = Uint8Array.from(binary, character => character.charCodeAt(0));

  return normalizeProductText(new TextDecoder().decode(bytes));
};

export const sortProductSizes = (sizes: string[]) => [...sizes].sort((a, b) => {
  const indexA = sizeOrder.indexOf(a);
  const indexB = sizeOrder.indexOf(b);
  if (indexA !== -1 || indexB !== -1) {
    return (indexA === -1 ? Number.MAX_SAFE_INTEGER : indexA) - (indexB === -1 ? Number.MAX_SAFE_INTEGER : indexB);
  }
  return a.localeCompare(b, 'pt-BR');
});

export const parseProductName = (name: string) => {
  const cleanName = normalizeProductText(name);
  const explicitSizeMatch = cleanName.match(/\bTAMANHO\s*-?\s*([A-Z0-9]+)\b/i);
  const trailingTokenMatch = cleanName.match(/(?:\s+-\s+|\s)([A-Z0-9]+)$/i);
  const trailingToken = trailingTokenMatch?.[1]?.toUpperCase() || '';
  let size = (explicitSizeMatch?.[1] || (sizeSet.has(trailingToken) ? trailingToken : '')).toUpperCase();

  const colorMatch = cleanName.match(/\bCOR\s+(.+?)(?:\s+TAMANHO|\s+-\s+[A-Z0-9]+$|$)/i);
  let color = normalizeProductText(findLeadingColor(colorMatch?.[1] || '') || colorMatch?.[1] || '');

  if (!color && size) {
    const nameBeforeSize = cleanName.replace(new RegExp(`(?:\\s+-\\s+|\\s)${escapeRegex(size)}$`, 'i'), '');
    color = findTrailingColor(nameBeforeSize);
  }

  if (!color) {
    const trailingColor = findTrailingColor(cleanName);
    if (trailingColor) {
      const normalizedName = normalizeForMatch(cleanName);
      const normalizedPrefix = normalizeProductText(normalizedName.replace(new RegExp(`${escapeRegex(trailingColor)}$`), ''));
      const tokenBeforeColor = normalizedPrefix.match(/([A-Z0-9]+)$/)?.[1] || '';
      if (sizeSet.has(tokenBeforeColor)) {
        color = trailingColor;
        size = tokenBeforeColor;
      }
    }
  }

  let baseName = cleanName
    .replace(/\bCOR\s+.+?(?:\s+TAMANHO\s*-?\s*[A-Z0-9]+|\s+-\s+[A-Z0-9]+$|$)/i, '')
    .replace(/\bTAMANHO\s*-?\s*[A-Z0-9]+\b/i, '')
    .replace(/\s+-\s*[A-Z0-9]+$/i, '');

  if (color && size) {
    const colorPattern = toFlexiblePattern(color);
    const sizePattern = escapeRegex(size);
    baseName = baseName
      .replace(new RegExp(`\\s+-\\s*${colorPattern}\\s+${sizePattern}$`, 'i'), '')
      .replace(new RegExp(`\\s+${colorPattern}\\s+-\\s*${sizePattern}$`, 'i'), '')
      .replace(new RegExp(`\\s+${sizePattern}\\s+${colorPattern}$`, 'i'), '')
      .replace(new RegExp(`\\s+${colorPattern}\\s+${sizePattern}$`, 'i'), '');
  }

  if (color) {
    const colorPattern = toFlexiblePattern(color);
    baseName = baseName
      .replace(new RegExp(`\\s+-\\s*${colorPattern}$`, 'i'), '')
      .replace(new RegExp(`\\s+${colorPattern}$`, 'i'), '');
  }

  baseName = normalizeProductText(baseName.replace(/\s+-\s*$/g, ''));

  return {
    baseName: baseName || cleanName,
    color,
    size
  };
};