package processors

import (
	"encoding/json"
	"fmt"
)

// RecursiveParse 将数据宝等返回中嵌套的 JSON 字符串递归解析为结构化数据。
func RecursiveParse(data interface{}) (interface{}, error) {
	switch v := data.(type) {
	case string:
		trimmed := trimSpace(v)
		if trimmed == "" {
			return v, nil
		}
		if !json.Valid([]byte(trimmed)) {
			return v, nil
		}
		var inner interface{}
		if err := json.Unmarshal([]byte(trimmed), &inner); err != nil {
			return v, nil
		}
		return RecursiveParse(inner)
	case map[string]interface{}:
		out := make(map[string]interface{}, len(v))
		for k, val := range v {
			parsed, err := RecursiveParse(val)
			if err != nil {
				return nil, fmt.Errorf("解析字段 %s 失败: %w", k, err)
			}
			out[k] = parsed
		}
		return out, nil
	case []interface{}:
		out := make([]interface{}, len(v))
		for i, val := range v {
			parsed, err := RecursiveParse(val)
			if err != nil {
				return nil, fmt.Errorf("解析数组下标 %d 失败: %w", i, err)
			}
			out[i] = parsed
		}
		return out, nil
	default:
		return data, nil
	}
}

func trimSpace(s string) string {
	start, end := 0, len(s)
	for start < end && (s[start] == ' ' || s[start] == '\n' || s[start] == '\r' || s[start] == '\t') {
		start++
	}
	for end > start && (s[end-1] == ' ' || s[end-1] == '\n' || s[end-1] == '\r' || s[end-1] == '\t') {
		end--
	}
	return s[start:end]
}