package lib

import (
	"bytes"
	"context"
	"errors"
	"fmt"
	"io"
	"net/http"
	"net/url"
)

type Forgejo struct {
	Server url.URL
	Token  string
	Branch string
}

type Info struct {
	LastModified string
	ETag         string
	Type         string
	Size         string
}

var ErrNotFound = errors.New("404 not found")

func (f *Forgejo) getFile(ctx context.Context, user, repo, branch, file string) (info Info, content io.Reader, err error) {
	u := f.Server
	u.Path = "/api/v1/repos/" + user + "/" + repo + "/raw/" + file
	p := u.Query()
	p.Set("ref", branch)
	u.RawQuery = p.Encode()
	fmt.Println(u.String())
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, u.String(), nil)
	if err != nil {
		return
	}

	req.Header.Set("Authorization", "token "+f.Token)
	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return
	}
	if resp.StatusCode == http.StatusNotFound {
		err = ErrNotFound
		return
	}

	info.LastModified = resp.Header.Get("Last-Modified")
	info.ETag = resp.Header.Get("Etag")
	info.Type = resp.Header.Get("X-Forgejo-Object-Type")
	info.Size = resp.Header.Get("Content-Length")
	content = resp.Body
	return
}

func (f *Forgejo) GetFile(ctx context.Context, user, repo, branch, file string) (info Info, content io.Reader, err error) {
	info, content, err = f.getFile(ctx, user, repo, branch, file)
	if err != nil {
		return
	}

	for info.Type == "symlink" {
		var data []byte
		data, err = io.ReadAll(content)
		if err != nil {
			return
		}
		if bytes.HasPrefix(data, []byte("/")) {
			err = ErrNotFound
			return
		}
		info, content, err = f.getFile(ctx, user, repo, branch, string(data))
		if err != nil {
			return
		}
	}

	return
}