decred.org/dcrwallet/v3@v3.1.0/internal/cfgutil/amount.go (about)

     1  // Copyright (c) 2015-2016 The btcsuite developers
     2  // Copyright (c) 2016 The Decred developers
     3  // Use of this source code is governed by an ISC
     4  // license that can be found in the LICENSE file.
     5  
     6  package cfgutil
     7  
     8  import (
     9  	"strconv"
    10  	"strings"
    11  
    12  	"github.com/decred/dcrd/dcrutil/v4"
    13  )
    14  
    15  // AmountFlag embeds a dcrutil.Amount and implements the flags.Marshaler and
    16  // Unmarshaler interfaces so it can be used as a config struct field.
    17  type AmountFlag struct {
    18  	dcrutil.Amount
    19  }
    20  
    21  // NewAmountFlag creates an AmountFlag with a default dcrutil.Amount.
    22  func NewAmountFlag(defaultValue dcrutil.Amount) *AmountFlag {
    23  	return &AmountFlag{defaultValue}
    24  }
    25  
    26  // MarshalFlag satisfies the flags.Marshaler interface.
    27  func (a *AmountFlag) MarshalFlag() (string, error) {
    28  	return a.Amount.String(), nil
    29  }
    30  
    31  // UnmarshalFlag satisfies the flags.Unmarshaler interface.
    32  func (a *AmountFlag) UnmarshalFlag(value string) error {
    33  	value = strings.TrimSuffix(value, " DCR")
    34  	valueF64, err := strconv.ParseFloat(value, 64)
    35  	if err != nil {
    36  		return err
    37  	}
    38  	amount, err := dcrutil.NewAmount(valueF64)
    39  	if err != nil {
    40  		return err
    41  	}
    42  	a.Amount = amount
    43  	return nil
    44  }