/**
 * 地址解析工具 - 使用关键词匹配方式解析省市区地址
 * 思路：通过省市区关键词截取，去两边留中间
 */

/**
 * 解析连续文本格式的地址
 * @param {string} fullAddress 完整地址字符串，如：山西省太原市迎泽区庙前街道劲松北路9号院
 * @returns {Object|null} 解析后的地址信息
 */
export const parseAddress = (fullAddress) => {
	if (!fullAddress || typeof fullAddress !== 'string') {
		console.warn('地址不能为空且必须为字符串');
		return null;
	}

	// 定义省市区关键词
	const provinceKeywords = /省|自治区|特别行政区/;
	const cityKeywords = /市|自治州|地区|盟/;
	const districtKeywords = /区|县|旗|自治县|自治旗|特区|林区/;

	// 1. 解析省份
	const provinceEndIndex = fullAddress.search(provinceKeywords);
	if (provinceEndIndex === -1) {
		// 处理直辖市情况
		const cityStartIndex = fullAddress.search(cityKeywords);
		if (cityStartIndex === -1) {
			console.warn('无法识别省份或城市');
			return null;
		}
		// 直辖市情况：如北京市海淀区
		const province = fullAddress.substring(0, cityStartIndex + 1);
		const city = province;

		// 解析区县
		const districtEndIndex = fullAddress.search(districtKeywords);
		if (districtEndIndex === -1) {
			console.warn('无法识别区县');
			return null;
		}
		const district = fullAddress.substring(city.length, districtEndIndex + 1);
		const street = fullAddress.substring(districtEndIndex + 1).trim();

		return {
			province,
			city,
			district,
			street: street || undefined
		};
	}

	// 2. 解析城市
	const province = fullAddress.substring(0, provinceEndIndex + 1);
	const remainingAfterProvince = fullAddress.substring(provinceEndIndex + 1);

	const cityEndIndex = remainingAfterProvince.search(cityKeywords);
	if (cityEndIndex === -1) {
		console.warn('无法识别城市');
		return null;
	}
	const city = remainingAfterProvince.substring(0, cityEndIndex + 1);
	const remainingAfterCity = remainingAfterProvince.substring(cityEndIndex + 1);

	// 3. 解析区县
	const districtEndIndex = remainingAfterCity.search(districtKeywords);
	if (districtEndIndex === -1) {
		console.warn('无法识别区县');
		return null;
	}
	const district = remainingAfterCity.substring(0, districtEndIndex + 1);
	const street = remainingAfterCity.substring(districtEndIndex + 1).trim();

	return {
		province,
		city,
		district,
		street: street || undefined
	};
};

/**
 * 仅获取省份名称
 * @param {string} fullAddress 完整地址字符串
 * @returns {string|null} 省份名称
 */
export const getProvince = (fullAddress) => {
	const result = parseAddress(fullAddress);
	return result?.province || null;
};

/**
 * 仅获取城市名称
 * @param {string} fullAddress 完整地址字符串
 * @returns {string|null} 城市名称
 */
export const getCity = (fullAddress) => {
	const result = parseAddress(fullAddress);
	return result?.city || null;
};

/**
 * 仅获取区县名称
 * @param {string} fullAddress 完整地址字符串
 * @returns {string|null} 区县名称
 */
export const getDistrict = (fullAddress) => {
	const result = parseAddress(fullAddress);
	return result?.district || null;
};

/**
 * 获取解析后的省市区数组（用于回显）
 * @param {string} fullAddress 完整地址字符串
 * @returns {Array} 省市区数组
 */
export const getAddressTree = (fullAddress) => {
	const result = parseAddress(fullAddress);
	if (!result) return [];
	return [result.province, result.city, result.district];
};

/**
 * 递归查找城市名称对应的areaCode
 * @param {string} cityName 城市名称
 * @param {Array} areaTree 省市区联级列表数据
 * @returns {string} 匹配到的areaCode，匹配不到返回空字符串
 */
export const findCityCodeByCname = (cityName, areaTree) => {
	// 边界条件检查
	if (!cityName || !areaTree || !Array.isArray(areaTree)) {
		return '';
	}
	// 遍历当前层级
	for (const area of areaTree) {
		// 匹配到城市名称，返回areaCode
		if (area.areaCname == cityName) {
			return area.areaCode;
		}

		// 如果有子节点，递归查找
		if (area.children && area.children.length > 0) {
			const foundCode = findCityCodeByCname(cityName, area.children);
			if (foundCode) {
				return foundCode;
			}
		}
	}

	// 所有节点都遍历完，没有匹配到
	return '';
};

// Vue 2 插件形式
const AddressParserPlugin = {
	install(Vue) {
		Vue.prototype.$parseAddress = parseAddress;
		Vue.prototype.$getProvince = getProvince;
		Vue.prototype.$getCity = getCity;
		Vue.prototype.$getDistrict = getDistrict;
		Vue.prototype.$getAddressTree = getAddressTree;
		Vue.prototype.$findCityCodeByCname = findCityCodeByCname;
	}
};

// 如果是在浏览器环境下直接使用
if (typeof window !== 'undefined' && window.Vue) {
	window.Vue.use(AddressParserPlugin);
}

// 导出插件形式
export default AddressParserPlugin;