topfreegames/khan

// khan
// https://github.com/topfreegames/khan
//
// Licensed under the MIT license:
// http://www.opensource.org/licenses/mit-license
// Copyright © 2016 Top Free Games <backend@tfgco.com>

package util

import (
    "encoding/json"
    "errors"

    "github.com/go-gorp/gorp"
)

//map[string]interface{} type
//type map[string]interface{} map[string]interface{}

//TypeConverter type
type TypeConverter struct{}

// ToDb converts val from json to string
func (tc TypeConverter) ToDb(val interface{}) (interface{}, error) {
    switch val.(type) {
    case map[string]interface{}:
        return json.Marshal(val)
    }
    return val, nil
}

// FromDb converts target from string to json
func (tc TypeConverter) FromDb(target interface{}) (gorp.CustomScanner, bool) {
    switch target.(type) {
    case *map[string]interface{}:
        binder := func(holder, target interface{}) error {
            s, ok := holder.(*string)
            if !ok {
                return errors.New("FromDb: Unable to convert map[string]interface{} to *string")
            }
            b := []byte(*s)
            return json.Unmarshal(b, target)
        }
        return gorp.CustomScanner{new(string), target, binder}, true
    }
    return gorp.CustomScanner{}, false
}