package main

import (
	"fmt"
	"reflect"
	"strings"
)

func BuildWhereQuery(params interface{}) string {
	conditions := []string{}
	v := reflect.ValueOf(params)
	t := v.Type()

	for i := 0; i < v.NumField(); i++ {
		field := v.Field(i)
		if field.Kind() == reflect.Ptr && !field.IsNil() {
			dbTag := t.Field(i).Tag.Get("db")
			if dbTag != "" {
				switch field.Elem().Kind() {
				case reflect.String:
					conditions = append(conditions, fmt.Sprintf("%s = '%s'", dbTag, field.Elem().String()))
				case reflect.Bool:
					conditions = append(conditions, fmt.Sprintf("%s = %t", dbTag, field.Elem().Bool()))
				case reflect.Int:
					conditions = append(conditions, fmt.Sprintf("%s = %d", dbTag, field.Elem().Int()))
				case reflect.Int64:
					conditions = append(conditions, fmt.Sprintf("%s = %d", dbTag, field.Elem().Int()))
				}
			}
		}
	}

	if len(conditions) > 0 {
		return "WHERE " + strings.Join(conditions, " AND ")
	}
	return ""
}