// 2018 Rackspace, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License"): you may
// not use this file except in compliance with the License. You may obtain
// a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations
// under the License.

package shutdown

import (
	"errors"
	"fmt"
	"regexp"
)

type adx struct {
	Opts          Options
	RawConfig     string
	StartupConfig string
	UpdatedConfig string
}

func (d *adx) modify() string {
	d.UpdatedConfig = d.RawConfig
	d.modifyMgmtInfo()
	d.modifyVlans()
	return d.UpdatedConfig
}

func (d *adx) modifyMgmtInfo() {
	if d.Opts.MgmtInfo == nil {
		return
	}

	re := regexp.MustCompile(
		fmt.Sprintf(
			`(?s)(interface management 1.*?ip address) %s %s(\b)`,
			d.Opts.MgmtInfo.IP.Old,
			d.Opts.MgmtInfo.Netmask.Old,
		))
	d.UpdatedConfig = re.ReplaceAllString(
		d.UpdatedConfig,
		fmt.Sprintf(`${1} %s %s${2}`, d.Opts.MgmtInfo.IP.New, d.Opts.MgmtInfo.Netmask.New),
	)

	re = regexp.MustCompile(fmt.Sprintf(`ip route (\S+ \S+) %s(\b)`, d.Opts.MgmtInfo.Gateway.Old))
	d.UpdatedConfig = re.ReplaceAllString(
		d.UpdatedConfig,
		fmt.Sprintf(`ip route ${1} %s${2}`, d.Opts.MgmtInfo.Gateway.New),
	)
}

func (d *adx) modifyVlans() {
	if d.Opts.VlanMap == nil {
		return
	}

	for o, n := range d.Opts.VlanMap {
		re := regexp.MustCompile(fmt.Sprintf(`vlan %s name (\S+) by port`, o))
		d.UpdatedConfig = re.ReplaceAllString(
			d.UpdatedConfig,
			fmt.Sprintf(`vlan %s name ${1} by port`, n),
		)
	}
}

func (d *adx) verify() error {
	if err := d.verifyMgmtInfo(); err != nil {
		return err
	}

	if err := d.verifyVlans(); err != nil {
		return err
	}

	return nil
}

func (d *adx) verifyMgmtInfo() error {
	if d.Opts.MgmtInfo == nil {
		return nil
	}
	re := regexp.MustCompile(
		fmt.Sprintf(
			`(?s)(interface management 1.*?ip address) %s %s(\b)`,
			d.Opts.MgmtInfo.IP.New,
			d.Opts.MgmtInfo.Netmask.New,
		),
	)
	if !re.MatchString(d.StartupConfig) {
		return errors.New("verify(): failure matching on updated mgmt IP")
	}
	return nil
}

func (d *adx) verifyVlans() error {
	if d.Opts.VlanMap == nil {
		return nil
	}
	vlans := make([]string, 0)
	for o := range d.Opts.VlanMap {
		re := regexp.MustCompile(fmt.Sprintf(`vlan %s name (\S+) by port`, o))
		if re.MatchString(d.RawConfig) {
			vlans = append(vlans, o)
		}
	}

	for _, oldVlan := range vlans {
		re := regexp.MustCompile(fmt.Sprintf(`vlan %s name (\S+) by port`, d.Opts.VlanMap[oldVlan]))
		if !re.MatchString(d.StartupConfig) {
			return fmt.Errorf("verify(): failure matching on vlan %s", d.Opts.VlanMap[oldVlan])
		}
	}
	return nil
}