<?php

namespace app\mzl\common\utils;

class SearchHelper
{
    public static function parseFiltersAndRelations(array $params, array $mapping): array
    {
        $filters = [];
        $relations = [];
        $hasRelations = [];

        // 解析过滤条件和关联字段
        foreach ($mapping as $paramKey => $definition) {
            $field = $definition['field'];
            $operator = $definition['operator'];
            $value = $params[$paramKey] ?? null;

            if (self::isValidValue($value, $operator)) {
                $filters[] = compact('field', 'operator', 'value');
                if (str_contains($field, '.')) {
                    $relations[] = self::extractRelationPath($field);
                }
            }
        }

        // 解析 whereHas 关联字段（如 profile.age）
        foreach ($params as $key => $value) {
            if (str_contains($key, '.')) {
                $relation = explode('.', $key)[0];  // 获取关联名
                $hasRelations[$relation] = function ($query) use ($key, $value) {
                    $query->where($key, '=', $value);
                };
            }
        }

        return [
            'filters' => $filters,
            'relations' => array_unique($relations),
            'hasRelations' => $hasRelations,
        ];
    }

    private static function isValidValue(mixed $value, string $operator): bool
    {
        $operator = strtolower($operator);

        if (in_array($operator, ['in', 'not_in', 'between'])) {
            return is_array($value) && !empty($value);
        }

        if (in_array($operator, ['null', 'not_null'])) {
            return true;
        }

        return $value !== '' && $value !== null;
    }

    private static function extractRelationPath(string $field): string
    {
        $parts = explode('.', $field);
        array_pop($parts);
        return implode('.', $parts);
    }
}