package main

import (
	"os"
	"strings"
	"testing"

	"lingniu-vehicle-ingest/go/vehicle-gateway/internal/envelope"
)

func TestNATSSinkConfigFromEnvUsesExplicitSubjects(t *testing.T) {
	t.Setenv("NATS_URL", "nats://172.17.111.56:4222")
	t.Setenv("NATS_SUBJECT_GB32960_RAW", "custom.raw.gb32960")
	t.Setenv("NATS_SUBJECT_JT808_RAW", "custom.raw.jt808")
	t.Setenv("NATS_SUBJECT_YUTONG_MQTT_RAW", "custom.raw.yutong")
	t.Setenv("NATS_SUBJECT_UNIFIED", "custom.unified")

	cfg := natsSinkConfigFromEnv()

	if got, want := cfg.URL, "nats://172.17.111.56:4222"; got != want {
		t.Fatalf("URL = %q, want %q", got, want)
	}
	if got, want := cfg.RawSubjects[envelope.ProtocolGB32960], "custom.raw.gb32960"; got != want {
		t.Fatalf("gb32960 subject = %q, want %q", got, want)
	}
	if got, want := cfg.RawSubjects[envelope.ProtocolJT808], "custom.raw.jt808"; got != want {
		t.Fatalf("jt808 subject = %q, want %q", got, want)
	}
	if got, want := cfg.RawSubjects[envelope.ProtocolYutongMQTT], "custom.raw.yutong"; got != want {
		t.Fatalf("yutong subject = %q, want %q", got, want)
	}
	if got, want := cfg.UnifiedSubject, "custom.unified"; got != want {
		t.Fatalf("unified subject = %q, want %q", got, want)
	}
}

func TestGatewayConfiguresIdentityLookupCacheTTL(t *testing.T) {
	source, err := os.ReadFile("main.go")
	if err != nil {
		t.Fatalf("read main.go: %v", err)
	}
	for _, want := range []string{"LookupCacheTTL", "IDENTITY_LOOKUP_CACHE_TTL_SECONDS"} {
		if !strings.Contains(string(source), want) {
			t.Fatalf("gateway should expose identity lookup cache ttl, missing %s", want)
		}
	}
}

func TestGatewayDefaultsTo100KConnectionCeiling(t *testing.T) {
	source, err := os.ReadFile("main.go")
	if err != nil {
		t.Fatalf("read main.go: %v", err)
	}
	if !strings.Contains(string(source), `envInt("TCP_MAX_CONNECTIONS", 120_000)`) {
		t.Fatal("gateway should default TCP_MAX_CONNECTIONS to a 100K-ready ceiling")
	}
}

func TestGatewayPassesMetricsRegistryToAsyncSink(t *testing.T) {
	source, err := os.ReadFile("main.go")
	if err != nil {
		t.Fatalf("read main.go: %v", err)
	}
	for _, want := range []string{
		"buildSink(ctx, logger, registry)",
		"Metrics:          registry",
		`Name:             "nats"`,
		`Name:             "kafka"`,
	} {
		if !strings.Contains(string(source), want) {
			t.Fatalf("gateway async sink metrics wiring missing %s", want)
		}
	}
}

func TestNATSSinkConfigFromEnvDefaultsToGoSubjects(t *testing.T) {
	t.Setenv("NATS_URL", "nats://172.17.111.56:4222")

	cfg := natsSinkConfigFromEnv()

	if got, want := cfg.RawSubjects[envelope.ProtocolGB32960], "vehicle.raw.go.gb32960.v1"; got != want {
		t.Fatalf("gb32960 subject = %q, want %q", got, want)
	}
	if got, want := cfg.RawSubjects[envelope.ProtocolJT808], "vehicle.raw.go.jt808.v1"; got != want {
		t.Fatalf("jt808 subject = %q, want %q", got, want)
	}
	if got, want := cfg.RawSubjects[envelope.ProtocolYutongMQTT], "vehicle.raw.go.yutong-mqtt.v1"; got != want {
		t.Fatalf("yutong subject = %q, want %q", got, want)
	}
	if got, want := cfg.UnifiedSubject, "vehicle.event.go.unified.v1"; got != want {
		t.Fatalf("unified subject = %q, want %q", got, want)
	}
}