// -=-=- StartHere -=-=-
//
// # Chapter V: QUIC handshaking
//
// This chapter describes measuring QUIC handshakes. Conceptually,
// and code wise, this is very similar to the previous chapter.
// The API call, in fact, has exactly the same structure, though
// under the hood QUIC is different because there are no
// separate connection establishment and handshake primitives.
// For this reason, we will not see a connect event, but we
// will only see a "QUIC handshake event".
//
// Having said that, let us now move on and see the code of
// the simple program that uses this functionality.
//
// (This file is auto-generated. Do not edit it directly! To apply
// changes you need to modify `./internal/tutorial/measure/chapter05/main.go`.)
//
// ## main.go
//
// The initial part of the program is pretty much the same as the one
// used in previous chapters, so I will not add further comments.
//
// ```Go
package main

import (
	"context"
	"crypto/tls"
	"encoding/json"
	"flag"
	"fmt"
	"time"

	"github.com/ooni/probe-cli/v3/internal/measurex"
	"github.com/ooni/probe-cli/v3/internal/netxlite"
	"github.com/ooni/probe-cli/v3/internal/runtimex"
)

func main() {
	sni := flag.String("sni", "dns.google", "value for SNI extension")
	address := flag.String("address", "8.8.4.4:443", "remote endpoint address")
	timeout := flag.Duration("timeout", 60*time.Second, "timeout to use")
	flag.Parse()
	ctx, cancel := context.WithTimeout(context.Background(), *timeout)
	defer cancel()
	mx := measurex.NewMeasurerWithDefaultSettings()
	// ```
	//
	// ### Handshaking with QUIC
	//
	// The API signature is indeed the same as the previous chapter,
	// except that here we call the `QUICHandshake` function.
	//
	// ```Go
	m := mx.QUICHandshake(ctx, *address, &tls.Config{
		ServerName: *sni,
		NextProtos: []string{"h3"},
		RootCAs:    netxlite.NewDefaultCertPool(),
	})
	// ```
	//
	// The same remarks mentioned in the previous chapter regarding
	// the arguments for the TLS config also apply here. We need
	// to specify the SNI (`ServerName`), the ALPN (`NextProtos`),
	// and the CA pool we want to use. Here, again, we're using
	// the CA pool from cURL that we bundle with OONI Probe.
	//
	// As we did in the previous chapters, here's the usual three
	// lines of code for printing the resulting measurement.
	//
	// ```
	data, err := json.Marshal(measurex.NewArchivalEndpointMeasurement(m))
	runtimex.PanicOnError(err, "json.Marshal failed")
	fmt.Printf("%s\n", string(data))
}

// ```
//
// ## Running the example program
//
// As before, let us start off with a vanilla run:
//
// ```bash
// go run -race ./internal/tutorial/measurex/chapter05 | jq
// ```
//
// Produces this JSON:
//
// ```JavaScript
// {
//   // In chapter02 these two fields were similar but
//   // the network was "tcp" as opposed to "udp"
//   "network": "udp",
//   "address": "8.8.4.4:443",
//
//   // This block contains I/O operations. Note that
//   // the protocol is "udp" and that the syscalls
//   // are "read_from" and "write_to" because QUIC does
//   // not bind/connect sockets. (The real syscalls
//   // are actually `recvfrom` and `sendto` but here
//   // we follow the Go convention of using read/write
//   // more frequently than send/recv.)
//   "network_events": [
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 1252,
//       "operation": "write_to",
//       "proto": "udp",
//       "t": 0.027184208,
//       "started": 0.027127208,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 1252,
//       "operation": "read_from",
//       "proto": "udp",
//       "t": 0.053116458,
//       "started": 0.025626583,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 1252,
//       "operation": "write_to",
//       "proto": "udp",
//       "t": 0.054538792,
//       "started": 0.054517542,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 1252,
//       "operation": "read_from",
//       "proto": "udp",
//       "t": 0.069144958,
//       "started": 0.053194208,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 1252,
//       "operation": "read_from",
//       "proto": "udp",
//       "t": 0.069183458,
//       "started": 0.069173292,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 1252,
//       "operation": "read_from",
//       "proto": "udp",
//       "t": 0.06920225,
//       "started": 0.069197875,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 1216,
//       "operation": "read_from",
//       "proto": "udp",
//       "t": 0.069210958,
//       "started": 0.069206875,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 65,
//       "operation": "read_from",
//       "proto": "udp",
//       "t": 0.069220667,
//       "started": 0.069217375,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 44,
//       "operation": "write_to",
//       "proto": "udp",
//       "t": 0.069433417,
//       "started": 0.069417625,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 44,
//       "operation": "write_to",
//       "proto": "udp",
//       "t": 0.069677625,
//       "started": 0.069647458,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 83,
//       "operation": "write_to",
//       "proto": "udp",
//       "t": 0.073461917,
//       "started": 0.073432875,
//       "oddity": ""
//     },
//     {
//       "address": "8.8.4.4:443",
//       "failure": null,
//       "num_bytes": 33,
//       "operation": "write_to",
//       "proto": "udp",
//       "t": 0.073559417,
//       "started": 0.073542542,
//       "oddity": ""
//     }
//   ],
//
//   // This section describes the QUIC handshake and it has
//   // basically the same fields as the TLS handshake.
//   "quic_handshakes": [
//     {
//       "cipher_suite": "TLS_CHACHA20_POLY1305_SHA256",
//       "failure": null,
//       "negotiated_proto": "h3",
//       "tls_version": "TLSv1.3",
//       "peer_certificates": [
//         {
//           "data": "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",
//           "format": "base64"
//         },
//         {
//           "data": "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",
//           "format": "base64"
//         },
//         {
//           "data": "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",
//           "format": "base64"
//         }
//       ],
//       "t": 0.073469208,
//       "address": "8.8.4.4:443",
//       "server_name": "dns.google",
//       "alpn": [
//         "h3"
//       ],
//       "no_tls_verify": false,
//       "oddity": "",
//       "proto": "udp",
//       "started": 0.025061583
//     }
//   ]
// }
// ```
//
// Here are some suggestions for other experiments to run:
//
// 1. obtain a timeout by connecting to a port that is not
// actually listening for QUIC;
//
// 2. obtain a certificate validation error by forcing
// a different SNI;
//
// 3. use a different ALPN (by changing the code), and see
// how the error and the oddity are handled. Can we do
// anything about this by changing `./internal/netxlite/errorx`
// to better support this specific error condition?
//
// ## Conclusion
//
// We have seen how to perform QUIC handshake and
// collect measurements.
//
// -=-=- StopHere -=-=-