/*
Copyright 2011 Google Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package main

import (
	"flag"
	"fmt"
	"log"
	"net/http"
	"net/url"
	"os"
	"strconv"
	"strings"

	"camlistore.org/pkg/client"
	"camlistore.org/pkg/cmdmain"
	"camlistore.org/pkg/httputil"
	"camlistore.org/pkg/jsonsign"
)

const buffered = 16 // arbitrary

var (
	flagProxyLocal = false
	flagHTTP       = flag.Bool("verbose_http", false, "show HTTP request summaries")
)

var cachedUploader *Uploader // initialized by getUploader

func init() {
	if debug, _ := strconv.ParseBool(os.Getenv("CAMLI_DEBUG")); debug {
		flag.BoolVar(&flagProxyLocal, "proxy_local", false, "If true, the HTTP_PROXY environment is also used for localhost requests. This can be helpful during debugging.")
	}
	cmdmain.ExtraFlagRegistration = func() {
		client.AddFlags()
	}
	cmdmain.PreExit = func() {
		up := getUploader()
		stats := up.Stats()
		log.Printf("Client stats: %s", stats.String())
		log.Printf("  #HTTP reqs: %d", up.transport.Requests())
	}
}

func getUploader() *Uploader {
	if cachedUploader == nil {
		cachedUploader = newUploader()
	}
	return cachedUploader
}

func handleResult(what string, pr *client.PutResult, err error) error {
	if err != nil {
		log.Printf("Error putting %s: %s", what, err)
		cmdmain.ExitWithFailure = true
		return err
	}
	fmt.Println(pr.BlobRef.String())
	return nil
}

func getenvEitherCase(k string) string {
	if v := os.Getenv(strings.ToUpper(k)); v != "" {
		return v
	}
	return os.Getenv(strings.ToLower(k))
}

// proxyFromEnvironment is similar to http.ProxyFromEnvironment but it skips
// $NO_PROXY blacklist so it proxies every requests, including localhost
// requests.
func proxyFromEnvironment(req *http.Request) (*url.URL, error) {
	proxy := getenvEitherCase("HTTP_PROXY")
	if proxy == "" {
		return nil, nil
	}
	proxyURL, err := url.Parse(proxy)
	if err != nil || proxyURL.Scheme == "" {
		if u, err := url.Parse("http://" + proxy); err == nil {
			proxyURL = u
			err = nil
		}
	}
	if err != nil {
		return nil, fmt.Errorf("invalid proxy address %q: %v", proxy, err)
	}
	return proxyURL, nil
}

func newUploader() *Uploader {
	cc := client.NewOrFail()
	if !*cmdmain.FlagVerbose {
		cc.SetLogger(nil)
	}

	var transport http.RoundTripper
	proxy := http.ProxyFromEnvironment
	if flagProxyLocal {
		proxy = proxyFromEnvironment
	}
	tlsConfig, err := cc.TLSConfig()
	if err != nil {
		log.Fatalf("Error while configuring TLS for client: %v", err)
	}
	transport = &http.Transport{
		Dial:            cc.DialFunc(),
		TLSClientConfig: tlsConfig,
		Proxy:           proxy,
	}

	httpStats := &httputil.StatsTransport{
		VerboseLog: *flagHTTP,
		Transport:  transport,
	}
	transport = httpStats

	if client.AndroidOutput() {
		transport = client.AndroidStatsTransport{transport}
	}
	cc.SetHTTPClient(&http.Client{Transport: transport})

	pwd, err := os.Getwd()
	if err != nil {
		log.Fatalf("os.Getwd: %v", err)
	}

	return &Uploader{
		Client:    cc,
		transport: httpStats,
		pwd:       pwd,
		entityFetcher: &jsonsign.CachingEntityFetcher{
			Fetcher: &jsonsign.FileEntityFetcher{File: cc.SecretRingFile()},
		},
	}
}

func main() {
	cmdmain.Main()
}