/*
 * Copyright (C) Max Romanov
 * Copyright (C) NGINX, Inc.
 */

package unit

/*
#include "nxt_cgo_lib.h"
*/
import "C"

import (
	"net/http"
)

type response struct {
	header     http.Header
	headerSent bool
	req        *http.Request
	c_req      C.uintptr_t
}

func new_response(c_req C.uintptr_t, req *http.Request) *response {
	resp := &response{
		header: http.Header{},
		req:    req,
		c_req:  c_req,
	}

	return resp
}

func (r *response) Header() http.Header {
	return r.header
}

func (r *response) Write(p []byte) (n int, err error) {
	if !r.headerSent {
		r.WriteHeader(http.StatusOK)
	}

	res := C.nxt_cgo_response_write(r.c_req, buf_ref(p), C.uint32_t(len(p)))
	return int(res), nil
}

func (r *response) WriteHeader(code int) {
	if r.headerSent {
		// Note: explicitly using Stderr, as Stdout is our HTTP output.
		nxt_go_warn("multiple response.WriteHeader calls")
		return
	}
	r.headerSent = true

	// Set a default Content-Type
	if _, hasType := r.header["Content-Type"]; !hasType {
		r.header.Add("Content-Type", "text/html; charset=utf-8")
	}

	fields := 0
	fields_size := 0

	for k, vv := range r.header {
		for _, v := range vv {
			fields++
			fields_size += len(k) + len(v)
		}
	}

	C.nxt_cgo_response_create(r.c_req, C.int(code), C.int(fields),
		C.uint32_t(fields_size))

	for k, vv := range r.header {
		for _, v := range vv {
			C.nxt_cgo_response_add_field(r.c_req, str_ref(k), C.uint8_t(len(k)),
				str_ref(v), C.uint32_t(len(v)))
		}
	}

	C.nxt_cgo_response_send(r.c_req)
}

func (r *response) Flush() {
	if !r.headerSent {
		r.WriteHeader(http.StatusOK)
	}
}