package main

import (
	"crypto/sha1"
	"encoding/hex"
	"errors"
	"fmt"
	"io"
	"os"
	"path/filepath"

	"github.com/go-resty/resty/v2"
	"github.com/schollz/progressbar/v3"
)

type UploadCommand struct {
	Url   string `short:"u" long:"url" description:"Url of the instance" required:"true"`
	Token string `short:"t" long:"token" description:"Token of the instance" required:"true"`
	File  string `short:"f" long:"file" description:"File to upload" required:"true"`
}

type UploadError struct {
	Error string
}

type UploadChunkSuccess struct {
	Checksum string
}

type UploadFileRequest struct {
	Name     string
	Checksum string
	Chunks   []string
}

type UploadFileResponse struct {
	Sum      string
	NbChunks uint32
	Size     uint64
}

func (c *UploadCommand) Execute(args []string) error {
	f, err := os.Open(c.File)
	if err != nil {
		return err
	}
	defer f.Close()

	st, err := f.Stat()
	if err != nil {
		return err
	}

	uploadFile := &UploadFileRequest{Name: filepath.Base(c.File)}
	progress := progressbar.DefaultBytes(st.Size(), fmt.Sprintf("Uploading %s", uploadFile.Name))
	defer progress.Close()

	cli := resty.New().SetBaseURL(c.Url).SetAuthScheme("Private").SetAuthToken(c.Token)
	b := make([]byte, 1<<20)
	checksum := sha1.New()
	for {
		n, err := f.Read(b)
		if n == 0 {
			if err == io.EOF {
				break
			}
			return err
		}

		resp, err := cli.R().SetError(&UploadError{}).SetResult(&UploadChunkSuccess{}).SetBody(b[0:n]).Post("/file/chunk")
		if err != nil {
			return err
		}

		if err, ok := resp.Error().(*UploadError); ok {
			return errors.New(err.Error)
		}

		if result, ok := resp.Result().(*UploadChunkSuccess); ok {
			uploadFile.Chunks = append(uploadFile.Chunks, result.Checksum)
			checksum.Write(b[0:n])
			progress.Add(n)
		}
	}

	uploadFile.Checksum = hex.EncodeToString(checksum.Sum(nil))

	resp, err := cli.R().SetBody(uploadFile).SetError(&UploadError{}).SetResult(&UploadFileResponse{}).Post("/file")
	if err != nil {
		return err
	}

	if err, ok := resp.Error().(*UploadError); ok {
		logger.Println("Upload failed")
		return errors.New(err.Error)
	}

	if result, ok := resp.Result().(*UploadFileResponse); ok {
		fmt.Printf("Upload succeed\nSum: %s\nNbChunks: %d\nSize: %d\n", result.Sum, result.NbChunks, result.Size)
	}

	return nil
}

func init() {
	parser.AddCommand("upload", "Upload a file", "", &UploadCommand{})
}