(function installLTJTSourceRegion(root, factory) {
  const api = factory();
  if (typeof module !== 'undefined' && module.exports) module.exports = api;
  if (root) root.LTJTSourceRegion = api;
}(typeof self !== 'undefined' ? self : globalThis, () => {
  'use strict';

  // These are source-market tokens, not a general-purpose address parser.
  // They are used only as an optional customer-keyword disambiguator. Product
  // and customer candidates are no longer required to share source-market
  // tokens before an ERP operation can continue.
  const SOURCE_REGION_TERMS = [
    '黑龙江', '内蒙古', '宁夏', '新疆', '西藏', '广西', '广东', '云南', '贵州', '四川',
    '重庆', '湖南', '湖北', '江西', '福建', '浙江', '江苏', '安徽', '山东', '河南',
    '河北', '山西', '陕西', '甘肃', '青海', '辽宁', '吉林', '海南', '北京', '上海',
    '天津', '香港', '澳门',
    '衡阳', '长沙', '株洲', '湘潭', '郴州', '永州', '岳阳', '常德', '邵阳', '怀化',
    '南宁', '桂林', '柳州', '广州', '深圳', '佛山', '东莞', '惠州', '珠海', '汕头',
    '湛江', '茂名', '肇庆', '江门', '中山', '揭阳', '清远', '韶关', '云浮', '河源',
    '昆明', '大理', '丽江', '西双版纳', '成都', '绵阳', '乐山', '贵阳', '遵义',
    '南昌', '九江', '赣州', '福州', '厦门', '泉州', '杭州', '宁波', '温州', '南京',
    '苏州', '无锡', '合肥', '济南', '青岛', '郑州', '石家庄', '太原', '西安',
    '兰州', '海口', '三亚', '沈阳', '长春', '哈尔滨'
  ];

  function normalizeSourceRegionText(value) {
    return String(value || '')
      .normalize('NFKC')
      .toLowerCase()
      .replace(/\s+/gu, '')
      .replace(/[“”‘’'"`【】\[\]（）()、，,。.:：;；/\\_|+]+/gu, '');
  }

  function refText(reference) {
    if (reference && typeof reference === 'object') {
      return [reference.source_region, reference.region, reference.keyword, reference.name]
        .filter((value) => value !== undefined && value !== null)
        .join(' ');
    }
    return String(reference || '');
  }

  function explicitSourceRegion(reference) {
    if (!reference || typeof reference !== 'object') return '';
    return String(reference.source_region || reference.region || '').trim();
  }

  function sourceRegionTokens(reference) {
    const explicit = explicitSourceRegion(reference);
    const text = normalizeSourceRegionText(explicit || refText(reference));
    if (!text) return [];
    const known = SOURCE_REGION_TERMS
      .filter((term) => text.includes(normalizeSourceRegionText(term)))
      .sort((left, right) => right.length - left.length);
    if (known.length) return known;
    return explicit ? [text] : [];
  }

  function uniqueSourceRegionCandidate(candidates, reference) {
    const sourceTokens = sourceRegionTokens(reference);
    if (!sourceTokens.length) {
      return {
        ok: false,
        applicable: false,
        reason: 'customer_source_region_token_missing',
        source_tokens: [],
        match_count: 0,
        candidate: null
      };
    }
    const matches = (Array.isArray(candidates) ? candidates : []).filter((candidate) => {
      const candidateText = normalizeSourceRegionText(refText(candidate));
      return sourceTokens.every((token) => candidateText.includes(normalizeSourceRegionText(token)));
    });
    return {
      ok: matches.length === 1,
      applicable: true,
      reason: matches.length === 1
        ? 'unique_source_region_candidate'
        : (matches.length > 1 ? 'ambiguous_source_region_candidates' : 'source_region_candidate_not_found'),
      source_tokens: sourceTokens,
      match_count: matches.length,
      candidate: matches.length === 1 ? matches[0] : null
    };
  }

  return {
    SOURCE_REGION_TERMS,
    normalizeSourceRegionText,
    sourceRegionTokens,
    uniqueSourceRegionCandidate
  };
}));