package connector

import (
	"bytes"
	"errors"
	"fmt"
	"io/ioutil"
	"net/http"
	"strings"

	"github.com/certusone/yubihsm-go/commands"
)

var ErrInvalidResponseValueLength = errors.New("invalid response value length")

type (
	// HTTPConnector implements the HTTP based connection with the YubiHSM2 connector
	HTTPConnector struct {
		URL string
	}
)

// NewHTTPConnector creates a new instance of HTTPConnector
func NewHTTPConnector(url string) *HTTPConnector {
	return &HTTPConnector{
		URL: url,
	}
}

// Request encodes and executes a command on the HSM and returns the binary response
func (c *HTTPConnector) Request(command *commands.CommandMessage) (data []byte, err error) {
	var requestData []byte
	requestData, err = command.Serialize()
	if err != nil {
		return
	}

	var res *http.Response
	res, err = http.DefaultClient.Post("http://"+c.URL+"/connector/api", "application/octet-stream", bytes.NewReader(requestData))
	if err != nil {
		return
	}

	defer func() {
		closeErr := res.Body.Close()
		if err == nil {
			err = closeErr
		}
	}()

	if res.StatusCode != http.StatusOK {
		err = fmt.Errorf("server returned non OK status code %d", res.StatusCode)
		return
	}

	data, err = ioutil.ReadAll(res.Body)

	return
}

// GetStatus requests the status of the HSM connector route /connector/status
func (c *HTTPConnector) GetStatus() (status *StatusResponse, err error) {
	var res *http.Response
	res, err = http.DefaultClient.Get("http://" + c.URL + "/connector/status")
	if err != nil {
		return
	}

	var data []byte
	data, err = ioutil.ReadAll(res.Body)
	if err != nil {
		return
	}

	bodyString := string(data)
	pairs := strings.Split(bodyString, "\n")

	var values []string
	for _, pair := range pairs {
		values = append(values, strings.Split(pair, "=")...)
	}

	if values == nil || len(values) < 12 {
		return nil, ErrInvalidResponseValueLength
	}

	status = &StatusResponse{}
	status.Status = Status(values[1])
	status.Serial = values[3]
	status.Version = values[5]
	status.Pid = values[7]
	status.Address = values[9]
	status.Port = values[11]

	err = res.Body.Close()

	return
}