package cmd

import (
	"context"
	"crypto/tls"
	"flag"
	"fmt"
	"log"
	"strings"
	"time"

	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials"

	statsv1 "github.com/bergabruh/stats-gateway/gen/stats/v1"
)

func Aggregate(args []string) {
	fs := flag.NewFlagSet("aggregate", flag.ExitOnError)
	server := fs.String("server", "stats.projectshitpost.fun:443", "gRPC endpoint host:port")
	node := fs.String("node", "", "fl|pl1 (empty = both)")
	since := fs.String("since", "", "RFC3339 lower bound (defaults to 24h ago)")
	until := fs.String("until", "", "RFC3339 upper bound (defaults to now)")
	timeout := fs.Duration("timeout", 10*time.Second, "")
	fs.Parse(args)

	if *since == "" {
		// Default to 24h ago for convenience.
		*since = time.Now().UTC().Add(-24 * time.Hour).Format(time.RFC3339)
	}

	conn, err := grpc.NewClient(*server,
		grpc.WithTransportCredentials(credentials.NewTLS(&tls.Config{})))
	if err != nil {
		log.Fatalf("dial: %v", err)
	}
	defer conn.Close()

	client := statsv1.NewSpeedStatusClient(conn)
	ctx, cancel := context.WithTimeout(context.Background(), *timeout)
	defer cancel()

	hist, err := client.Aggregate(ctx, &statsv1.Range{
		Node:  *node,
		Since: *since,
		Until: *until,
	})
	if err != nil {
		log.Fatalf("Aggregate: %v", err)
	}

	fmt.Printf("Histogram of HTTP latency (ms) — node=%q since=%s\n", *node, *since)
	for _, b := range hist.Buckets {
		bar := ""
		if b.Count > 0 {
			n := int(b.Count)
			if n > 60 {
				n = 60
			}
			bar = strings.Repeat("#", n)
		}
		fmt.Printf("  <= %6.0fms  %5d  %s\n", b.UpperMs, b.Count, bar)
	}
}