package cfg

import (
	"fmt"
	"io"
	"log"
	"net"
	"net/http"
	"path"
	"strconv"
	"strings"
	"time"

	fcgiclient "github.com/alash3al/go-fastcgi-client"
	"go.stargrave.org/godlighty"
)

func ServeFCGI(
	w http.ResponseWriter,
	r *http.Request,
	host, docRoot, scriptName, sockProto, sockPath string,
	timeout time.Duration,
) {
	defer r.Body.Close()
	serverHost, serverPort, err := net.SplitHostPort(godlighty.BindAddr)
	if err != nil {
		panic(err)
	}
	remoteAddr, remotePort, _ := net.SplitHostPort(r.RemoteAddr)
	params := map[string]string{
		"GATEWAY_INTERFACE": "CGI/1.1",

		"PATH_INFO":    r.URL.Path,
		"QUERY_STRING": r.URL.RawQuery,

		"REMOTE_ADDR": remoteAddr,
		"REMOTE_PORT": remotePort,

		"SERVER_NAME":     serverHost,
		"SERVER_PORT":     serverPort,
		"SERVER_PROTOCOL": r.Proto,
		"SERVER_SOFTWARE": godlighty.Version,

		"REQUEST_METHOD":  r.Method,
		"DOCUMENT_ROOT":   docRoot,
		"SCRIPT_NAME":     scriptName,
		"SCRIPT_FILENAME": path.Join(docRoot, scriptName),
	}
	for k, vs := range r.Header {
		if len(vs) < 1 {
			continue
		}
		k = "HTTP_" + strings.ToUpper(strings.Replace(k, "-", "_", -1))
		params[k] = strings.Join(vs, ";")
	}
	c, err := fcgiclient.Dial(sockProto, sockPath)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		log.Println("can not FCGI:", err)
		return
	}
	defer c.Close()
	c.SetReadTimeout(timeout)
	c.SetSendTimeout(timeout)
	resp, err := c.Request(params, r.Body)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		log.Println("can not FCGI:", err)
		return
	}
	defer resp.Body.Close()
	for k, vs := range resp.Header {
		for _, v := range vs {
			w.Header().Add(k, v)
		}
	}
	if resp.ContentLength > 0 {
		w.Header().Set("Content-Length", strconv.FormatInt(resp.ContentLength, 10))
	}
	w.WriteHeader(resp.StatusCode)
	written, err := io.Copy(w, resp.Body)
	if err != nil {
		stderr := c.Stderr()
		log.Println("can not copy FCGI:", string(stderr.Bytes()))
		return
	}
	fmt.Printf("%s %s \"%s %+q %s\" %d %d \"%s\"\n",
		r.RemoteAddr, host, r.Method, godlighty.PathWithQuery(r.URL), r.Proto,
		resp.StatusCode, written,
		r.Header.Get("User-Agent"),
	)
}