package main

import (
	"context"
	"io"
	"net"
	"net/http"
	"testing"
	"time"

	"mqtt_washingmachine/internal/sensor"
	"mqtt_washingmachine/internal/web"
)

func TestLoadConfigDefaults(t *testing.T) {
	for _, key := range []string{"MQTT_BROKER", "MQTT_TOPIC", "MQTT_USERNAME", "MQTT_PASSWORD", "HTTP_ADDR", "SAMPLE_INTERVAL"} {
		t.Setenv(key, "")
	}
	got, err := loadConfig()
	if err != nil {
		t.Fatal(err)
	}
	if got.Broker != "tcp://192.168.1.11:1883" || got.Topic != "tele/tasmota_washingmashine_C21183/SENSOR" || got.HTTPAddr != ":8080" || got.SampleInterval != time.Minute || got.Username != "" || got.Password != "" {
		t.Fatalf("defaults: %+v", got)
	}
}

func TestHTTPServerShutdownWithOpenStream(t *testing.T) {
	var sampler sensor.Sampler
	var hub sensor.Hub
	server := newHTTPServer(t.Context(), web.NewHandler(sampler.Status, &hub))
	if server.WriteTimeout != 10*time.Second {
		t.Fatalf("write timeout = %v", server.WriteTimeout)
	}
	listener, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatal(err)
	}
	defer server.Close()
	served := make(chan error, 1)
	go func() { served <- server.Serve(listener) }()
	client := &http.Client{Timeout: 3 * time.Second}
	response, err := client.Get("http://" + listener.Addr().String() + "/api/events")
	if err != nil {
		t.Fatal(err)
	}
	defer response.Body.Close()
	initial := make([]byte, len("event: update\ndata: {}\n\n"))
	if _, err := io.ReadFull(response.Body, initial); err != nil {
		t.Fatal(err)
	}
	ctx, cancel := context.WithTimeout(t.Context(), time.Second)
	defer cancel()
	if err := server.Shutdown(ctx); err != nil {
		t.Fatalf("open stream delayed shutdown: %v", err)
	}
	if body, err := io.ReadAll(response.Body); err != nil || len(body) != 0 {
		t.Fatalf("stream did not close cleanly: %q, %v", body, err)
	}
	if err := <-served; err != http.ErrServerClosed {
		t.Fatalf("Serve = %v", err)
	}
}

func TestLoadConfigOverrides(t *testing.T) {
	for key, value := range map[string]string{"MQTT_BROKER": "tcp://localhost:1884", "MQTT_TOPIC": "test/power", "MQTT_USERNAME": "tester", "MQTT_PASSWORD": "test-password", "HTTP_ADDR": "127.0.0.1:9090", "SAMPLE_INTERVAL": "250ms"} {
		t.Setenv(key, value)
	}
	got, err := loadConfig()
	if err != nil {
		t.Fatal(err)
	}
	if got.Broker != "tcp://localhost:1884" || got.Topic != "test/power" || got.Username != "tester" || got.Password != "test-password" || got.HTTPAddr != "127.0.0.1:9090" || got.SampleInterval != 250*time.Millisecond {
		t.Fatal("environment overrides not applied")
	}
}

func TestLoadConfigRejectsInvalidInterval(t *testing.T) {
	for _, interval := range []string{"nonsense", "0s", "-1s", "60"} {
		t.Run(interval, func(t *testing.T) {
			t.Setenv("SAMPLE_INTERVAL", interval)
			if _, err := loadConfig(); err == nil {
				t.Fatalf("accepted SAMPLE_INTERVAL=%q", interval)
			}
		})
	}
}