// Copyright 2015 CoreOS, 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 digitalocean

import (
	"encoding/json"
	"strconv"

	"github.com/coreos/coreos-cloudinit/datasource/metadata"
)

const (
	DefaultAddress = "http://169.254.169.254/"
	apiVersion     = "metadata/v1"
	userdataUrl    = apiVersion + "/user-data"
	metadataPath   = apiVersion + ".json"
)

type Address struct {
	IPAddress string `json:"ip_address"`
	Netmask   string `json:"netmask"`
	Cidr      int    `json:"cidr"`
	Gateway   string `json:"gateway"`
}

type Interface struct {
	IPv4 *Address `json:"ipv4"`
	IPv6 *Address `json:"ipv6"`
	MAC  string   `json:"mac"`
	Type string   `json:"type"`
}

type Interfaces struct {
	Public  []Interface `json:"public"`
	Private []Interface `json:"private"`
}

type DNS struct {
	Nameservers []string `json:"nameservers"`
}

type Metadata struct {
	Hostname   string     `json:"hostname"`
	Interfaces Interfaces `json:"interfaces"`
	PublicKeys []string   `json:"public_keys"`
	DNS        DNS        `json:"dns"`
}

type metadataService struct {
	interfaces Interfaces
	dns        DNS
	metadata.MetadataService
}

func NewDatasource(root string) *metadataService {
	return &metadataService{MetadataService: metadata.NewDatasource(root, apiVersion, userdataUrl, metadataPath)}
}

func (ms *metadataService) FetchMetadata() ([]byte, error) {
	data, err := ms.FetchData(ms.MetadataUrl())
	if err != nil || len(data) == 0 {
		return []byte{}, err
	}

	var metadata Metadata
	if err := json.Unmarshal(data, &metadata); err != nil {
		return []byte{}, err
	}

	ms.interfaces = metadata.Interfaces
	ms.dns = metadata.DNS

	attrs := make(map[string]interface{})
	if len(metadata.Interfaces.Public) > 0 {
		if metadata.Interfaces.Public[0].IPv4 != nil {
			attrs["public-ipv4"] = metadata.Interfaces.Public[0].IPv4.IPAddress
		}
		if metadata.Interfaces.Public[0].IPv6 != nil {
			attrs["public-ipv6"] = metadata.Interfaces.Public[0].IPv6.IPAddress
		}
	}
	if len(metadata.Interfaces.Private) > 0 {
		if metadata.Interfaces.Private[0].IPv4 != nil {
			attrs["local-ipv4"] = metadata.Interfaces.Private[0].IPv4.IPAddress
		}
		if metadata.Interfaces.Private[0].IPv6 != nil {
			attrs["local-ipv6"] = metadata.Interfaces.Private[0].IPv6.IPAddress
		}
	}
	attrs["hostname"] = metadata.Hostname
	keys := make(map[string]string)
	for i, key := range metadata.PublicKeys {
		keys[strconv.Itoa(i)] = key
	}
	attrs["public_keys"] = keys

	return json.Marshal(attrs)
}

func (ms metadataService) FetchNetworkConfig(filename string) ([]byte, error) {
	return json.Marshal(Metadata{
		Interfaces: ms.interfaces,
		DNS:        ms.dns,
	})
}

func (ms metadataService) Type() string {
	return "digitalocean-metadata-service"
}