enum IQueryParamsArrayFormatEnum {
	brackets = 'brackets',
	indices = 'indices',
	repeat = 'repeat',
	comma = 'comma',
}
interface IQueryParamsData {
	[key: string]: string;
}
/**
 * 对象转url参数
 * @param {*} data,对象
 * @param {*} isPrefix,是否自动加上"?"
 */
function queryParams(data: IQueryParamsData = {}, isPrefix: boolean = true, arrayFormat: string = 'brackets') {
	let prefix = isPrefix ? '?' : '';
	let _result = [];
	if (['indices', 'brackets', 'repeat', 'comma'].indexOf(arrayFormat) == -1) arrayFormat = 'brackets';
	for (let key in data) {
		let value: any = data[key];
		// 去掉为空的参数
		if (['', undefined, null].indexOf(value) >= 0) {
			continue;
		}
		// 如果值为数组，另行处理
		if (value.constructor === Array) {
			// e.g. {ids: [1, 2, 3]}
			switch (arrayFormat) {
				case 'indices':
					// 结果: ids[0]=1&ids[1]=2&ids[2]=3
					for (let i = 0; i < value.length; i++) {
						_result.push(key + '[' + i + ']=' + value[i]);
					}
					break;
				case 'brackets':
					// 结果: ids[]=1&ids[]=2&ids[]=3
					value.forEach(_value => {
						_result.push(key + '[]=' + _value);
					});
					break;
				case 'repeat':
					// 结果: ids=1&ids=2&ids=3
					value.forEach(_value => {
						_result.push(key + '=' + _value);
					});
					break;
				case 'comma':
					// 结果: ids=1,2,3
					let commaStr = "";
					value.forEach(_value => {
						commaStr += (commaStr ? "," : "") + _value;
					});
					_result.push(key + '=' + commaStr)
					break;
				default:
					value.forEach(_value => {
						_result.push(key + '[]=' + _value);
					});
			}
		} else {
			_result.push(key + '=' + value);
		}
	}
	return _result.length ? prefix + _result.join('&') : ''
}

export default queryParams;