package gemini

import (
	"bufio"
	"errors"
	"io"
	"net/url"

	"tildegit.org/tjp/gus"
)

// InvalidRequestLineEnding indicates that a gemini request didn't end with "\r\n".
var InvalidRequestLineEnding = errors.New("invalid request line ending")

// ParseRequest parses a single gemini request from a reader.
func ParseRequest(rdr io.Reader) (*gus.Request, error) {
	line, err := bufio.NewReader(rdr).ReadString('\n')
	if err != io.EOF && err != nil {
		return nil, err
	}

	if len(line) < 2 || line[len(line)-2:] != "\r\n" {
		return nil, InvalidRequestLineEnding
	}

	u, err := url.Parse(line[:len(line)-2])
	if err != nil {
		return nil, err
	}

	if u.Scheme == "" {
		u.Scheme = "gemini"
	}

	return &gus.Request{URL: u}, nil
}