// Package main provides a utility named ct-sans.
//
// Install:
//
//	go install git.cs.kau.se/rasmoste/ct-sans@latest
//
// Usage:
//
//	$ ct-sans -h
package main

import (
	"flag"
	"fmt"
	"log"
	"os"
	"time"

	"git.cs.kau.se/rasmoste/ct-sans/internal/ctflag"
)

const usage = `ct-sans collects SANs in CT-logged certificates

Usage:

  ct-sans snapshot [Options...]
    Refresh log lists, signed tree heads, and timestamps

  ct-sans collect [Options...]
    Collect SANs with regards to the current snapshot

  ct-sans assemble [Options...]
    Assemble dataset from the collected data (requires GNU sort)

Help:

  ct-sans [-h] [--help]

Snapshot options:

  -d, --directory:   The ct-sans working directory (Default: "data")

Collect options:

  -d, --directory:   The ct-sans working directory (Default: "data")
  -w, --workers:     Max number of parallel download workers per log (Default: 2).
  -k, --batch-disk:  Certificate batch size before persisting (Default: 256)
  -q, --batch-req:   Certificate batch size to use in request (Default: 128)
  -a, --http-agent:  HTTP agent to use in all request (Default: "git.cs.kau.se/rasmoste/ct-sans")
  -m, --metrics:     How often to emit metrics to stderr (Default: 16s)

Asemble options:

  -d, --directory:   The ct-sans working directory (Default: "data")
  -b, --buffer-size: Max memory to use in Gigabytes (Default: 1)
  -t, --temp-dir:    Temporary on-disk storage directory (Default: /tmp)
  -p, --parallel:    Number of CPUs to use (Default: 1)

`

type options struct {
	// Common options
	Directory string

	// Collect options
	WorkersPerLog   uint64
	PersistSize     uint64
	BatchSize       uint64
	HTTPAgent       string
	MetricsInterval time.Duration

	// Assemble options
	BufferSize uint64
	TempDir    string
	Parallel   uint64

	// Constants
	logDirectory          string
	archiveDirectory      string
	metadataFile          string
	metadataSignatureFile string
	metadataTimestampFile string
	sthFile               string
	sthsFile              string
	stateFile             string
	sansFile              string
	visitFile             string
	noticeFile            string
}

func main() {
	log.SetOutput(os.Stdout)
	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)
	if ctflag.WantHelp(os.Args, 1) {
		fmt.Fprintf(os.Stdout, usage)
		os.Exit(1)
	}

	// Define command-line options
	fs := ctflag.NewFlagSet()
	opts := options{}
	ctflag.String(&fs, &opts.Directory, "directory", "d", "data")

	ctflag.Uint64(&fs, &opts.WorkersPerLog, "workers", "w", 2)
	ctflag.Uint64(&fs, &opts.PersistSize, "batch-disk", "k", 256)
	ctflag.Uint64(&fs, &opts.BatchSize, "batch-req", "q", 128)
	ctflag.String(&fs, &opts.HTTPAgent, "http-agent", "a", "git.cs.kau.se/rasmoste/ct-sans")
	ctflag.Duration(&fs, &opts.MetricsInterval, "metrics", "m", 16*time.Second)

	ctflag.Uint64(&fs, &opts.BufferSize, "buffer-size", "b", 1)
	ctflag.String(&fs, &opts.TempDir, "temp-dir", "t", "/tmp")
	ctflag.Uint64(&fs, &opts.Parallel, "parallel", "p", 1)

	// Parse command-line options and hardcode additional values
	if err := ctflag.Parse(fs, os.Args[2:]); err != nil {
		if err == flag.ErrHelp {
			fmt.Fprintf(os.Stdout, usage)
			os.Exit(1)
		}

		fmt.Fprintf(os.Stdout, "error: %v\n\n", err)
		os.Exit(1)
	}
	opts.logDirectory = opts.Directory + "/" + "logs"
	opts.archiveDirectory = opts.Directory + "/" + "archive"
	opts.metadataFile = "metadata.json"
	opts.metadataSignatureFile = "metadata.sig"
	opts.metadataTimestampFile = "metadata.timestamp"
	opts.sthFile = "sth.json"
	opts.sthsFile = "sths.json"
	opts.stateFile = "th.json"
	opts.sansFile = "sans.lst"
	opts.visitFile = "visit.lst"
	opts.noticeFile = "notice.txt"

	// Hand-over to the respective subcommands
	var err error
	switch cmd := os.Args[1]; cmd {
	case "snapshot":
		err = snapshot(opts)
	case "collect":
		err = collect(opts)
	case "assemble":
		err = assemble(opts)
	default:
		fmt.Fprintf(os.Stdout, "ct-sans: unknown command %q\n\n", cmd)
		os.Exit(1)
	}
	if err != nil {
		fmt.Fprintf(os.Stdout, "ct-sans %s: error: %v\n", os.Args[1], err)
		os.Exit(1)
	}
}