package narco

import (
	"log"
	"os"
	"strings"
	"time"

	"github.com/codemodus/chain"
	"github.com/pivotal-golang/bytefmt"
	"golang.org/x/net/context"

	"net/http"
)

type Logger struct {
	//may want a level based logger
	*log.Logger
}

// to make the logger accessible for modification
func NewLogger() *Logger {
	return &Logger{log.New(os.Stdout, "[narco] ", log.LstdFlags)}
}

func (l *Logger) Wrap() func(chain.Handler) chain.Handler {
	return func(other chain.Handler) chain.Handler {
		return chain.HandlerFunc(func(ctx context.Context, h http.ResponseWriter, r *http.Request) {
			start := time.Now()
			uAgentList, ok := r.Header["User-Agent"]
			var uAgent string
			if ok == false {
				uAgent = "<unknown>"
			} else {
				uAgent = strings.Join(uAgentList, "; ")
			}

			remote := r.RemoteAddr
			if len(remote) == 0 {
				remote = "<unknown>"
			}

			l.Printf("Requested %s on %s from %s (User-Agent: %s)", r.Method, r.URL.Path, remote, uAgent)

			//wrap the request with our own interface
			hh := WrapResponseWritter(h)

			other.ServeHTTPContext(ctx, hh, r)

			l.Printf("returned %d: %s, size: %s in %s",
				hh.Status(),
				http.StatusText(hh.Status()),
				bytefmt.ByteSize(uint64(hh.Size())),
				time.Since(start))
		})
	}
}