// This is Free Software under GNU Affero General Public License v >= 3.0
// without warranty, see README.md and license for details.
//
// SPDX-License-Identifier: AGPL-3.0-or-later
// License-Filename: LICENSES/AGPL-3.0.txt
//
// Copyright (C) 2018 by via donau
//   – Österreichische Wasserstraßen-Gesellschaft mbH
// Software engineering by Intevation GmbH
//
// Author(s):
//  * Sascha L. Teichmann <sascha.teichmann@intevation.de>

package common

import (
	"log"
	"strconv"
	"strings"
	"time"
)

type (

	// Attributes is a map of optional key/value attributes
	// of a configuration.
	Attributes map[string]string

	AttributesMarshaler interface {
		MarshalAttributes(Attributes) error
	}

	AttributesUnmarshaler interface {
		UnmarshalAttributes(Attributes) error
	}
)

func (ca Attributes) Unmarshal(dst interface{}) error {
	if ca == nil {
		return nil
	}
	var err error
	if um, ok := dst.(AttributesUnmarshaler); ok {
		err = um.UnmarshalAttributes(ca)
	}
	return err
}

func (ca Attributes) Delete(key string) bool {
	if ca == nil {
		return false
	}
	if _, found := ca[key]; !found {
		return false
	}
	delete(ca, key)
	return true
}

// Get fetches a value for given key out of the configuration.
// If the key was not found the bool component of the return value
// return false.
func (ca Attributes) Get(key string) (string, bool) {
	if ca == nil {
		return "", false
	}
	value, found := ca[key]
	return value, found
}

func (ca Attributes) Set(key, value string) bool {
	if ca == nil {
		return false
	}
	ca[key] = value
	return true
}

// Bool returns a bool value for a given key.
func (ca Attributes) Bool(key string) bool {
	s, found := ca.Get(key)
	return found && strings.ToLower(s) == "true"
}

func (ca Attributes) SetBool(key string, value bool) bool {
	var v string
	if value {
		v = "true"
	} else {
		v = "false"
	}
	return ca.Set(key, v)
}

const TimeFormat = "2006-01-02T15:04:05"

// Time gives a time.Time for a given key.
func (ca Attributes) Time(key string) (time.Time, bool) {
	s, found := ca.Get(key)
	if !found {
		return time.Time{}, false
	}
	t, err := time.Parse(TimeFormat, s)
	if err != nil {
		log.Printf("error: %v\n", err)
		return time.Time{}, false
	}
	return t, true
}

func (ca Attributes) SetTime(key string, t time.Time) bool {
	value := t.Format(TimeFormat)
	return ca.Set(key, value)

}

func (ca Attributes) Int(key string) (int, bool) {
	s, found := ca.Get(key)
	if !found {
		return 0, false
	}
	i, err := strconv.Atoi(s)
	if err != nil {
		log.Printf("error: %v\n", err)
		return 0, false
	}
	return i, true
}

func (ca Attributes) SetInt(key string, value int) bool {
	v := strconv.Itoa(value)
	return ca.Set(key, v)
}

func (ca Attributes) Duration(key string) (time.Duration, bool) {
	s, found := ca.Get(key)
	if !found {
		return 0, false
	}
	d, err := time.ParseDuration(s)
	if err != nil {
		log.Printf("error: %v\n", err)
		return 0, false
	}
	return d, true
}

func (ca Attributes) SetDuration(key string, value time.Duration) bool {
	v := value.String()
	return ca.Set(key, v)
}