utils.go

// Copyright 2019 xgfone
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package gconf

import (
	"crypto/md5"
	"crypto/sha256"
	"fmt"
	"strings"
	"time"

	"github.com/xgfone/cast"
)

// Some type converters, all of which have a default implementation,
// but you can reset them to yourself implementations.
var (
	ToBool     = cast.ToBool     // func(interface{}) (bool, error)
	ToInt      = cast.ToInt      // func(interface{}) (int, error)
	ToInt32    = cast.ToInt32    // func(interface{}) (int32, error)
	ToInt64    = cast.ToInt64    // func(interface{}) (int64, error)
	ToUint     = cast.ToUint     // func(interface{}) (uint, error)
	ToUint32   = cast.ToUint32   // func(interface{}) (uint32, error)
	ToUint64   = cast.ToUint64   // func(interface{}) (uint64, error)
	ToFloat64  = cast.ToFloat64  // func(interface{}) (float64, error)
	ToString   = cast.ToString   // func(interface{}) (string, error)
	ToDuration = cast.ToDuration // func(interface{}) (time.Duration, error)
	ToTime     = toTime          // func(interface{}) (time.Time, error)

	// For string type, it will be split by using cast.ToStringSlice.
	ToIntSlice      = toIntSlice      // func(interface{}) ([]int, error)
	ToUintSlice     = toUintSlice     // func(interface{}) ([]uint, error)
	ToFloat64Slice  = toFloat64Slice  // func(interface{}) ([]float64, error)
	ToStringSlice   = toStringSlice   // func(interface{}) ([]string, error)
	ToDurationSlice = toDurationSlice // func(interface{}) ([]time.Duration, error)
)

var toStringMap = cast.ToStringMap

func init() {
	cast.StringSeparator = " ,"
}

func toTime(v interface{}) (time.Time, error) {
	return cast.ToTime(v)
}

func bytesToMd5(data []byte) string {
	h := md5.New()
	h.Write(data)
	return fmt.Sprintf("%x", h.Sum(nil))
}

func bytesToSha256(data []byte) string {
	h := sha256.New()
	h.Write(data)
	return fmt.Sprintf("%x", h.Sum(nil))
}

func getStringSlice(value interface{}) []string {
	var s string
	switch v := value.(type) {
	case []string:
		return v
	case string:
		s = v
	case []byte:
		s = string(v)
	case fmt.Stringer:
		s = v.String()
	default:
		return nil
	}

	vs, _ := cast.ToStringSlice(s)
	ss := make([]string, 0, len(vs))
	for _, s := range vs {
		if s = strings.TrimSpace(s); s != "" {
			ss = append(ss, s)
		}
	}
	return ss
}

func toIntSlice(value interface{}) ([]int, error) {
	if ss := getStringSlice(value); ss != nil {
		var err error
		vs := make([]int, len(ss))
		for i, s := range ss {
			if vs[i], err = ToInt(s); err != nil {
				return []int{}, fmt.Errorf("unable to cast %#v of type %T to []int", value, value)
			}
		}
		return vs, nil
	}
	return cast.ToIntSlice(value)
}

func toUintSlice(value interface{}) (v []uint, err error) {
	if ss := getStringSlice(value); ss != nil {
		var err error
		vs := make([]uint, len(ss))
		for i, s := range ss {
			if vs[i], err = ToUint(s); err != nil {
				return []uint{}, fmt.Errorf("unable to cast %#v of type %T to []uint", value, value)
			}
		}
		return vs, nil
	}
	return cast.ToUintSlice(value)
}

func toFloat64Slice(value interface{}) ([]float64, error) {
	if ss := getStringSlice(value); ss != nil {
		var err error
		vs := make([]float64, len(ss))
		for i, s := range ss {
			if vs[i], err = ToFloat64(s); err != nil {
				return []float64{}, fmt.Errorf("unable to cast %#v of type %T to []float64", value, value)
			}
		}
		return vs, nil
	}
	return cast.ToFloat64Slice(value)
}

func toStringSlice(value interface{}) ([]string, error) {
	if ss := getStringSlice(value); ss != nil {
		return ss, nil
	}
	return cast.ToStringSlice(value)
}

func toDurationSlice(value interface{}) ([]time.Duration, error) {
	if ss := getStringSlice(value); ss != nil {
		var err error
		vs := make([]time.Duration, len(ss))
		for i, s := range ss {
			if vs[i], err = ToDuration(s); err != nil {
				return []time.Duration{}, fmt.Errorf("unable to cast %#v of type %T to []time.Duration", value, value)
			}
		}
		return vs, nil
	}
	return cast.ToDurationSlice(value)
}