package web

import (
	"io"
	"net/http"
)

// Response is the interface for an HTTP response.
type Response interface {
	Flush()
	Header(key string) string
	SetHeader(key string, value string)
	Write([]byte) (int, error)
	WriteString(string) (int, error)
}

// response represents the HTTP response used in the given context.
type response struct {
	http.ResponseWriter
}

// Flush flushes the response buffers to the client.
func (res response) Flush() {
	flusher, ok := res.ResponseWriter.(http.Flusher)

	if ok {
		flusher.Flush()
	}
}

// Header returns the header value for the given key.
func (res response) Header(key string) string {
	return res.ResponseWriter.Header().Get(key)
}

// SetHeader sets the header value for the given key.
func (res response) SetHeader(key string, value string) {
	res.ResponseWriter.Header().Set(key, value)
}

// Write implements the io.Writer interface.
func (res response) Write(body []byte) (int, error) {
	return res.ResponseWriter.Write(body)
}

// WriteString implements the io.StringWriter interface.
func (res response) WriteString(body string) (int, error) {
	return res.ResponseWriter.(io.StringWriter).WriteString(body)
}