// Copyright 2024 Matthew Rich <matthewrich.conf@gmail.com>. All rights reserved.

package transport

import (
_	"errors"
	"fmt"
	"net/url"
	"net/http"
_	"strings"
	"path/filepath"
	"io"
	"os"
)

type Reader struct {
	uri *url.URL
	handle any
	stream io.ReadCloser
}

func NewReader(u *url.URL) (*Reader, error) {
	var e error
	r := &Reader{ uri: u }
	switch u.Scheme {
	case "http", "https":
		resp, err := http.Get(u.String())
		r.handle = resp
		r.stream = resp.Body
		e = err
	case "file":
		fallthrough
	default:
		path := filepath.Join(u.Hostname(), u.RequestURI())
		file, err := os.Open(path)
		r.handle = file
		r.stream = file
		e = err
	}
	return r, e
}

type Writer struct {

}

func NewWriter(url *url.URL) (*Writer, error) {
	return nil, nil
}

func (r *Reader) Read(b []byte) (int, error) {
	return r.stream.Read(b)
}

func (r *Reader) Close() error {
	return r.stream.Close()
}

func (r *Reader) Signature() string {
	documentSignature := r.handle.(*http.Response).Header.Get("Signature")
	if documentSignature == "" {
		signatureResp, signatureErr := http.Get(fmt.Sprintf("%s.sig", r.uri.String()))
		if signatureErr == nil {
			defer signatureResp.Body.Close()
			readSignatureBody, readSignatureErr := io.ReadAll(signatureResp.Body)
			if readSignatureErr == nil {
				documentSignature = string(readSignatureBody)
			}
		}
	}
	return documentSignature
}