package client

import (
	"context"
	"crypto/tls"
	"fmt"
	"io"
	"net/http"
	"os"
	"path/filepath"
	"strconv"
)

type Client struct {
	username string
	password string
}

func NewClient() *Client {
	return &Client{}
}

func NewClientWithAuth(username, password string) *Client {
	return &Client{
		username: username,
		password: password,
	}
}

func (cli *Client) ServiceHello(ctx context.Context, ref string) (bool, error) {
	var res bool
	var err error

	ref, err = convertServiceRefer(ref)
	if err != nil {
		return res, err
	}
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, ref, nil)
	if err != nil {
		return res, err
	}

	transport := &http.Transport{
		TLSClientConfig: &tls.Config{
			InsecureSkipVerify: true,
		},
	}
	client := &http.Client{
		Transport: transport,
	}
	resp, err := client.Do(req)
	if err != nil {
		return res, err
	}
	defer resp.Body.Close()
	if resp.StatusCode == http.StatusOK {
		res = true
	}
	return res, err
}

func (cli *Client) FileExists(ctx context.Context, ref string) (bool, error) {
	var res bool
	var err error

	ref, err = convertFileRefer(ref)
	if err != nil {
		return res, err
	}
	req, err := http.NewRequestWithContext(ctx, http.MethodHead, ref, nil)
	if err != nil {
		return res, err
	}

	if cli.username != "" && cli.password != "" {
		req.Header.Add("Authorization", encodeBasicAuth(cli.username, cli.password))
	}

	transport := &http.Transport{
		TLSClientConfig: &tls.Config{
			InsecureSkipVerify: true,
		},
	}
	client := &http.Client{
		Transport: transport,
	}
	resp, err := client.Do(req)
	if err != nil {
		return res, err
	}
	defer resp.Body.Close()
	if resp.StatusCode == http.StatusOK {
		res = true
	}
	return res, err
}

func (cli *Client) PutFile(ctx context.Context, filename, ref string) error {
	var err error
	ref, err = convertFileRefer(ref)
	if err != nil {
		return err
	}
	file, err := os.Open(filename)
	if err != nil {
		return err
	}
	defer file.Close()

	req, err := http.NewRequestWithContext(ctx, http.MethodPut, ref, file)
	if err != nil {
		return err
	}

	if cli.username != "" && cli.password != "" {
		req.Header.Add("Authorization", encodeBasicAuth(cli.username, cli.password))
	}

	transport := &http.Transport{
		TLSClientConfig: &tls.Config{
			InsecureSkipVerify: true,
		},
	}
	client := &http.Client{
		Transport: transport,
	}
	fileinfo, err := os.Stat(filename)
	if err != nil {
		return err
	}
	filesize := fileinfo.Size()

	req.ContentLength = filesize
	req.Header.Set("Content-Type", "application/octet-stream")

	resp, err := client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		err := fmt.Errorf("Received wrong status code: %s", resp.Status)
		return err
	}
	return err
}

func (cli *Client) GetFile(ctx context.Context, ref, filename string) (int64, error) {
	var err error
	var size int64
	ref, err = convertFileRefer(ref)
	if err != nil {
		return size, err
	}

	req, err := http.NewRequestWithContext(ctx, http.MethodGet, ref, nil)
	if err != nil {
		return size, err
	}

	if cli.username != "" && cli.password != "" {
		req.Header.Add("Authorization", encodeBasicAuth(cli.username, cli.password))
	}

	transport := &http.Transport{
		TLSClientConfig: &tls.Config{
			InsecureSkipVerify: true,
		},
	}
	client := &http.Client{
		Transport: transport,
	}
	resp, err := client.Do(req)
	if err != nil {
		return size, err
	}
	defer resp.Body.Close()

	contentLength := resp.Header.Get("Content-Length")
	if contentLength == "" {
		err = fmt.Errorf("Empty Content-Length received")
		return size, err
	}
	if resp.StatusCode != http.StatusOK {
		err := fmt.Errorf("Received wrong status code: %s", resp.Status)
		return size, err
	}
	declSize, err := strconv.ParseInt(contentLength, 10, 64)
	if err != nil {
		err = fmt.Errorf("Wrong Content-Length value: %v", err)
		return size, err
	}
	dirname := filepath.Dir(filename)
	err = os.MkdirAll(dirname, 0750)
	if err != nil {
		return size, err
	}
	file, err := os.OpenFile(filename, os.O_WRONLY|os.O_CREATE, 0640)
	if err != nil {
		return size, err
	}
	size, err = io.Copy(file, resp.Body)
	if err != nil {
		return size, err
	}
	if size != declSize {
		err := fmt.Errorf("Mismatch Content-Length and recorded filesize")
		return size, err
	}
	return size, err
}

func (cli *Client) DeleteFile(ctx context.Context, ref, filename string) error {
	var err error
	ref, err = convertFileRefer(ref)
	if err != nil {
		return err
	}
	req, err := http.NewRequestWithContext(ctx, http.MethodDelete, ref, nil)
	if err != nil {
		return err
	}

	if cli.username != "" && cli.password != "" {
		req.Header.Add("Authorization", encodeBasicAuth(cli.username, cli.password))
	}

	transport := &http.Transport{
		TLSClientConfig: &tls.Config{
			InsecureSkipVerify: true,
		},
	}
	client := &http.Client{
		Transport: transport,
	}
	resp, err := client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		err := fmt.Errorf("Received wrong status code: %s", resp.Status)
		return err
	}
	return err
}