package http

import (
	"bufio"
	"errors"
	"fmt"
	"io"
	"net"
	"strconv"
	"strings"
)

func Do(method string, url string) (*Response, error) {
	path := "/"
	arr := strings.Split(url, "/")
	if len(arr) == 2 {
		path = arr[1]
	}
	if !strings.HasPrefix(path, "/") {
		path = "/" + path
	}

	conn, err := net.Dial("tcp", arr[0])
	if err != nil {
		return nil, errors.New("connect " + arr[0])
	}
	defer conn.Close()

	WriteRequest(conn, method, path, "HTTP/1.0")
	return ReadResponse(conn)
}

func WriteRequest(w io.Writer, method string, path string, httpVersion string) {
	fmt.Fprintf(w, "%s %s %s\r\n\r\n", method, path, httpVersion)
}

func ReadResponse(r io.Reader) (*Response, error) {
	response := &Response{}

	b := bufio.NewReader(r)

	status, err := b.ReadString('\n')
	if err != nil {
		return response, errors.New("read status")
	}
	arr := strings.Split(status, " ")
	response.StatusCode, err = strconv.Atoi(arr[1])
	if err != nil {
		return response, errors.New("read status code")
	}

	headerStr := ""
	for {
		headerStr, err = b.ReadString('\n')
		if err != nil {
			return response, errors.New("read header")
		}
		if headerStr == "\r\n" {
			break
		}
		arr := strings.Split(headerStr, ": ")
		value := strings.TrimSpace(arr[1])
		response.Headers = append(response.Headers, &Header{Name: arr[0], Value: value})
	}

	contentTypeHeader, err := response.GetHeader("Content-Length")
	if err != nil {
		return response, errors.New("get Content-Length")
	}
	length, err := strconv.Atoi(contentTypeHeader.Value)
	if err != nil {
		return response, errors.New("read Content-Length")
	}

	body := make([]byte, 0, length)

	for i := 0; i < length; i++ {
		r, err := b.ReadByte()
		if err != nil {
			return response, errors.New("read body")
		}
		body = append(body, r)
	}
	response.Body = body

	return response, nil
}