package client

import (
	"context"
	"fmt"
	"io"
	"net/http"
	"strconv"
)

func (cli *Client) PatchUpload(ctx context.Context, rawref string, src io.Reader, uploc string, size int64) (string, error) {
	var err error
	var ouloc string

	ref, err := NewReference(rawref)
	if err != nil {
		return ouloc, err
	}
	uri, err := ref.Patch(uploc)
	if err != nil {
		return ouloc, err
	}
	user, pass := ref.Userinfo()

	req, err := http.NewRequestWithContext(ctx, http.MethodPatch, uri, src)
	if err != nil {
		return ouloc, err
	}
	req.Header.Set("User-Agent", cli.userAgent)
	req.Header.Set("Content-Type", "application/octet-stream")
	req.Header.Set("Content-Length", strconv.FormatInt(size, 10))
	if cli.authenticator != nil {
		authHeader, authKey, err := cli.authenticator.MakeHeader(user, pass)
		if err != nil {
			return ouloc, err
		}
		req.Header.Set(authHeader, authKey)
	}
	resp, err := cli.httpClient.Do(req)
	if err != nil {
		return ouloc, err
	}
	resp.Body.Close()
	if resp.StatusCode != http.StatusAccepted {
		err = fmt.Errorf("Upload not accepted, code %d", resp.StatusCode)
		return ouloc, err
	}
	ouloc = resp.Header.Get("Location")
	if ouloc == "" {
		err := fmt.Errorf("Empty blob location declaration")
		return ouloc, err
	}
	return ouloc, err
}