package utils

import (
	"crypto/md5"
	"encoding/hex"
	"reflect"
	"strings"
)

func StringOrDefault(a, b string) string {
	if len(a) == 0 {
		return b
	}
	return a
}

func GetStructForDatabase(s interface{}) []string {
	out := make([]string, 0)
	el := reflect.ValueOf(s).Elem()
	for i := 0; i < el.NumField(); i++ {
		t := el.Type().Field(i)
		tag := t.Tag
		db := tag.Get("db")
		if len(db) == 0 {
			out = append(out, strings.ToLower(t.Name))
		} else {
			out = append(out, db)
		}
	}
	return out
}

func GetNamedForDatabase(s interface{}) []string {
	out := make([]string, 0)
	el := reflect.ValueOf(s).Elem()
	for i := 0; i < el.NumField(); i++ {
		t := el.Type().Field(i)
		tag := t.Tag
		db := tag.Get("db")
		if len(db) == 0 {
			out = append(out, ":"+strings.ToLower(t.Name))
		} else {
			out = append(out, ":"+db)
		}
	}
	return out
}

func GetStructAndNamedForDatabase(s interface{}) [][]string {
	out := make([][]string, 0)
	el := reflect.ValueOf(s).Elem()
	for i := 0; i < el.NumField(); i++ {
		t := el.Type().Field(i)
		tag := t.Tag
		ignore := tag.Get("ignore")
		if ignore != "1" {
			db := tag.Get("db")
			if len(db) == 0 {
				out = append(out, []string{strings.ToLower(t.Name), ":" + strings.ToLower(t.Name)})
			} else {
				out = append(out, []string{db, ":" + db})
			}
		}
	}
	return out
}

func MD5(s string) string {
	hash := md5.New()
	hash.Write([]byte(s))
	return hex.EncodeToString(hash.Sum(nil))
}