// Copyright 2018-2019 gf Author(https://github.com/gogf/gf). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.

// Package gvar provides an universal variable type, like generics.
package gvar

import (
	"github.com/gogf/gf/g/container/gtype"
	"github.com/gogf/gf/g/os/gtime"
	"github.com/gogf/gf/g/util/gconv"
	"time"
)

// Var is an universal variable type.
type Var struct {
	value interface{} // Underlying value.
	safe  bool        // Concurrent safe or not.
}

// New returns a new Var with given <value>.
// The parameter <unsafe> used to specify whether using Var in un-concurrent-safety,
// which is false in default, means concurrent-safe.
func New(value interface{}, unsafe ...bool) *Var {
	v := &Var{}
	if len(unsafe) == 0 || !unsafe[0] {
		v.safe = true
		v.value = gtype.NewInterface(value)
	} else {
		v.value = value
	}
	return v
}

// Set sets <value> to <v>, and returns the old value.
func (v *Var) Set(value interface{}) (old interface{}) {
	if v.safe {
		old = v.value.(*gtype.Interface).Set(value)
	} else {
		old = v.value
		v.value = value
	}
	return
}

// Val returns the current value of <v>.
func (v *Var) Val() interface{} {
	if v.safe {
		return v.value.(*gtype.Interface).Val()
	}
	return v.value
}

// Interface is alias of Val.
func (v *Var) Interface() interface{} {
	return v.Val()
}

// Time converts and returns <v> as time.Time.
// The parameter <format> specifies the format of the time string using gtime,
// eg: Y-m-d H:i:s.
func (v *Var) Time(format ...string) time.Time {
	return gconv.Time(v.Val(), format...)
}

// Duration converts and returns <v> as time.Duration.
// If value of <v> is string, then it uses time.ParseDuration for conversion.
func (v *Var) Duration() time.Duration {
	return gconv.Duration(v.Val())
}

// GTime converts and returns <v> as *gtime.Time.
// The parameter <format> specifies the format of the time string using gtime,
// eg: Y-m-d H:i:s.
func (v *Var) GTime(format ...string) *gtime.Time {
	return gconv.GTime(v.Val(), format...)
}

// Struct maps value of <v> to <objPointer>.
// The parameter <objPointer> should be a pointer to a struct instance.
// The parameter <mapping> is used to specify the key-to-attribute mapping rules.
func (v *Var) Struct(pointer interface{}, mapping ...map[string]string) error {
	return gconv.Struct(v.Val(), pointer, mapping...)
}

// IsNil checks whether <v> is nil.
func (v *Var) IsNil() bool {
	return v.Val() == nil
}

// Bytes converts and returns <v> as []byte.
func (v *Var) Bytes() []byte {
	return gconv.Bytes(v.Val())
}

// String converts and returns <v> as string.
func (v *Var) String() string {
	return gconv.String(v.Val())
}

// Bool converts and returns <v> as bool.
func (v *Var) Bool() bool {
	return gconv.Bool(v.Val())
}

// Int converts and returns <v> as int.
func (v *Var) Int() int {
	return gconv.Int(v.Val())
}

// Int8 converts and returns <v> as int8.
func (v *Var) Int8() int8 {
	return gconv.Int8(v.Val())
}

// Int16 converts and returns <v> as int16.
func (v *Var) Int16() int16 {
	return gconv.Int16(v.Val())
}

// Int32 converts and returns <v> as int32.
func (v *Var) Int32() int32 {
	return gconv.Int32(v.Val())
}

// Int64 converts and returns <v> as int64.
func (v *Var) Int64() int64 {
	return gconv.Int64(v.Val())
}

// Uint converts and returns <v> as uint.
func (v *Var) Uint() uint {
	return gconv.Uint(v.Val())
}

// Uint8 converts and returns <v> as uint8.
func (v *Var) Uint8() uint8 {
	return gconv.Uint8(v.Val())
}

// Uint16 converts and returns <v> as uint16.
func (v *Var) Uint16() uint16 {
	return gconv.Uint16(v.Val())
}

// Uint32 converts and returns <v> as uint32.
func (v *Var) Uint32() uint32 {
	return gconv.Uint32(v.Val())
}

// Uint64 converts and returns <v> as uint64.
func (v *Var) Uint64() uint64 {
	return gconv.Uint64(v.Val())
}

// Float32 converts and returns <v> as float32.
func (v *Var) Float32() float32 {
	return gconv.Float32(v.Val())
}

// Float64 converts and returns <v> as float64.
func (v *Var) Float64() float64 {
	return gconv.Float64(v.Val())
}

// Ints converts and returns <v> as []int.
func (v *Var) Ints() []int {
	return gconv.Ints(v.Val())
}

// Floats converts and returns <v> as []float64.
func (v *Var) Floats() []float64 {
	return gconv.Floats(v.Val())
}

// Strings converts and returns <v> as []string.
func (v *Var) Strings() []string {
	return gconv.Strings(v.Val())
}

// Interfaces converts and returns <v> as []interfaces{}.
func (v *Var) Interfaces() []interface{} {
	return gconv.Interfaces(v.Val())
}