// 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 models

import (
	"encoding/json"
	"errors"
	"time"

	"gemma.intevation.de/gemma/pkg/common"
	"github.com/robfig/cron"
)

type (
	// CronSpec is a string containing a cron line.
	CronSpec string

	ConfigTime struct{ time.Time }

	ConfigDuration struct{ time.Duration }

	EmailType struct {
		Email bool `json:"send-email,omitempty"`
	}

	QueueConfigurationType struct {
		EmailType
		Trys      *int            `json:"trys,omitempty"`
		WaitRetry *ConfigDuration `json:"wait-retry,omitempty"`
		Due       *ConfigTime     `json:"due,omitempty"`
		Cron      *CronSpec       `json:"cron,omitempty"`
	}

	URLType struct {
		URL      string  `json:"url"`
		Insecure bool    `json:"insecure,omitempty"`
		User     *string `json:"user,omitempty"`
		Password *string `json:"password,omitempty"`
	}

	EmailTypeGetter interface {
		GetEmailType() *EmailType
	}

	QueueConfigurationGetter interface {
		GetQueueConfiguration() *QueueConfigurationType
	}

	URLTypeGetter interface {
		GetURLType() *URLType
	}
)

func (qct *QueueConfigurationType) GetQueueConfiguration() *QueueConfigurationType {
	return qct
}

func (ut *URLType) GetURLType() *URLType {
	return ut
}

func (et *EmailType) GetEmailType() *EmailType {
	return et
}

func (cd *ConfigDuration) UnmarshalJSON(data []byte) error {
	var s string
	if err := json.Unmarshal(data, &s); err != nil {
		return err
	}
	dur, err := time.ParseDuration(s)
	if err != nil {
		return err
	}
	if dur < 0 {
		return errors.New("duration has to be none negative.")
	}
	*cd = ConfigDuration{dur}
	return nil
}

func (cd *ConfigDuration) MarshalJSON() ([]byte, error) {
	return json.Marshal(cd.Duration.String())
}

func (ct *ConfigTime) UnmarshalJSON(data []byte) error {
	var s string
	if err := json.Unmarshal(data, &s); err != nil {
		return err
	}
	t, err := time.Parse(common.TimeFormat, s)
	if err != nil {
		return err
	}
	*ct = ConfigTime{t}
	return nil
}

func (ct *ConfigTime) MarshalJSON() ([]byte, error) {
	s := ct.Time.Format(common.TimeFormat)
	return json.Marshal([]byte(s))
}

// UnmarshalJSON checks if the incoming string is a valid cron line.
func (cs *CronSpec) UnmarshalJSON(data []byte) error {
	var spec string
	if err := json.Unmarshal(data, &spec); err != nil {
		return err
	}
	if _, err := cron.Parse(spec); err != nil {
		return err
	}
	*cs = CronSpec(spec)
	return nil
}

func (et *EmailType) MarshalAttributes(attrs common.Attributes) error {
	if et.Email {
		attrs.SetBool("email", et.Email)
	}
	return nil
}

func (et *EmailType) UnmarshalAttributes(attrs common.Attributes) error {
	et.Email = attrs.Bool("email")
	return nil
}

func (qct *QueueConfigurationType) MarshalAttributes(attrs common.Attributes) error {
	if err := qct.EmailType.MarshalAttributes(attrs); err != nil {
		return err
	}
	if qct.Trys != nil {
		attrs.SetInt("trys", *qct.Trys)
	}
	if qct.WaitRetry != nil {
		attrs.SetDuration("wait-retry", qct.WaitRetry.Duration)
	}
	if qct.Due != nil {
		attrs.SetTime("due", qct.Due.Time)
	}
	if qct.Cron != nil {
		attrs.Set("cron", string(*qct.Cron))
	}
	return nil
}

func (qct *QueueConfigurationType) UnmarshalAttributes(attrs common.Attributes) error {
	if err := qct.EmailType.UnmarshalAttributes(attrs); err != nil {
		return err
	}
	if trys, found := attrs.Int("trys"); found {
		qct.Trys = &trys
	}
	if duration, found := attrs.Duration("wait-retry"); found {
		qct.WaitRetry = &ConfigDuration{duration}
	}
	if due, found := attrs.Time("due"); found {
		qct.Due = &ConfigTime{due}
	}
	if cron, found := attrs.Get("cron"); found {
		cs := CronSpec(cron)
		qct.Cron = &cs
	}
	return nil
}

func (ut *URLType) MarshalAttributes(attrs common.Attributes) error {
	attrs.Set("url", ut.URL)
	if ut.Insecure {
		attrs.SetBool("insecure", ut.Insecure)
	}
	if ut.User != nil {
		attrs.Set("user", *ut.User)
	}
	if ut.Password != nil {
		attrs.Set("password", *ut.Password)
	}
	return nil
}

func (ut *URLType) UnmarshalAttributes(attrs common.Attributes) error {
	url, found := attrs.Get("url")
	if !found {
		return errors.New("missing 'url' attribute")
	}
	ut.URL = url
	if insecure := attrs.Bool("insecure"); insecure {
		ut.Insecure = insecure
	}
	if user, found := attrs.Get("user"); found {
		ut.User = &user
	}
	if password, found := attrs.Get("password"); found {
		ut.Password = &password
	}
	return nil
}