// Mgmt
// Copyright (C) James Shubin and the project contributors
// Written by James Shubin <james@shubin.ca> and the project contributors
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.
//
// Additional permission under GNU GPL version 3 section 7
//
// If you modify this program, or any covered work, by linking or combining it
// with embedded mcl code and modules (and that the embedded mcl code and
// modules which link with this program, contain a copy of their source code in
// the authoritative form) containing parts covered by the terms of any other
// license, the licensors of this program grant you additional permission to
// convey the resulting work. Furthermore, the licensors of this program grant
// the original author, James Shubin, additional permission to update this
// additional permission if he deems it necessary to achieve the goals of this
// additional permission.

package resources

import (
	"context"
	"fmt"

	"github.com/cloudflare/cloudflare-go/v6"
	"github.com/purpleidea/mgmt/engine"
	"github.com/purpleidea/mgmt/engine/traits"
)

func init() {
	engine.RegisterResource("cloudflare:dns", func() engine.Res { return &CloudflareDNSRes{} })
}

// TODO: description of cloudflare_dns resource
type CloudflareDNSRes struct {
	traits.Base
	init *engine.Init

	APIToken string `lang:"apitoken"`

	Name string `lang:"name"`

	TTL int `lang:"ttl"`

	Type string `lang:"type"`

	Zone string `lang:"zone"`

	client *cloudflare.API
}

func (obj *CloudflareDNSRes) Validate() error {
	if obj.Name == "" {
		return fmt.Errorf("record name is required")
	}

	if obj.APIToken == "" {
		return fmt.Errorf("API token is required")
	}

	if obj.Type == "" {
		return fmt.Errorf("record type is required")
	}

	if obj.TTL < 60 || obj.TTL > 86400 { // API requirement
		return fmt.Errorf("TTL must be between 60 and 86400 seconds")
	}

	if obj.Zone == "" {
		return fmt.Errof("zone name is required")
	}

	return nil
}

func (obj *CloudflareDNSRes) Init(init *engine.Init) error {
	obj.init = init

	api, err := cloudflare.NewWithAPIToken(obj.APIToken)
	if err != nil {
		return fmt.Errorf("failed to init Cloudflare API client")
	}

	obj.client = api

	return nil
}

func (obj *CloudflareDNSRes) Cleanup() error {
	obj.APIToken = ""
	obj.client = nil
	return nil
}

// Watch isn't implemented for this resource, since the Cloudflare API does not
// provide any event stream. Instead, always use polling.
func (obj *CloudflareDNSRes) Watch(context.Context) error {
	return fmt.Errorf("invalid Watch call: requires poll metaparam")
}

func (obj *CloudflareDNSRes) CheckApply(ctx context.Context, apply bool) (bool, error) {
	zone, err := obj.client.Zones.List(ctx, zones.ZoneListParams{
		Name: cloudflare.F(obj.Zone),
	})
	if err != nil {
		return false, fmt.Errorf(err)
	}

	if len(zone.Result) == 0 {
		return false, fmt.Errorf("there's no zone registered with name %s", obj.Zone)
	}

	if len(zone.Result) > 1 {
		return false, fmt.Errorf("there's more than one zone with name %s", obj.Zone)
	}

}