package alertnotification

import (
	"context"
	"crypto/hmac"
	"crypto/sha256"
	"encoding/hex"
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"data-terminal-cloud/internal/outbox"
)

func TestProcessorDeliversSignedEnvelope(t *testing.T) {
	secret := "test-alert-webhook-secret-at-least-32-bytes"
	now := time.Unix(1_800_000_000, 0).UTC()
	var received bool
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		received = true
		body, err := io.ReadAll(r.Body)
		if err != nil {
			t.Fatal(err)
		}
		if r.Header.Get("X-Voice-Event-ID") != "10000000-0000-0000-0000-000000000001" || r.Header.Get("X-Voice-Timestamp") != "1800000000" {
			t.Fatalf("missing delivery identity headers")
		}
		mac := hmac.New(sha256.New, []byte(secret))
		_, _ = mac.Write([]byte("1800000000."))
		_, _ = mac.Write(body)
		want := "v1=" + hex.EncodeToString(mac.Sum(nil))
		if r.Header.Get("X-Voice-Signature") != want {
			t.Fatalf("signature=%q want=%q", r.Header.Get("X-Voice-Signature"), want)
		}
		var envelope webhookEnvelope
		if err = json.Unmarshal(body, &envelope); err != nil || envelope.EventType != "alert.webhook_requested" || string(envelope.Data) != `{"severity":"HIGH"}` {
			t.Fatalf("envelope=%+v err=%v", envelope, err)
		}
		w.WriteHeader(http.StatusNoContent)
	}))
	defer server.Close()
	processor, err := NewProcessor(server.URL, secret, time.Second)
	if err != nil {
		t.Fatal(err)
	}
	processor.now = func() time.Time { return now }
	event := outbox.Event{ID: "10000000-0000-0000-0000-000000000001", EventType: "alert.webhook_requested", Payload: json.RawMessage(`{"severity":"HIGH"}`)}
	if err = processor.Handle(context.Background(), event); err != nil {
		t.Fatal(err)
	}
	if !received {
		t.Fatal("webhook was not delivered")
	}
}

func TestProcessorRetryClassificationAndDisabledMode(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, _ *http.Request) {
		http.Error(w, "temporarily unavailable", http.StatusServiceUnavailable)
	}))
	defer server.Close()
	processor, err := NewProcessor(server.URL, "test-alert-webhook-secret-at-least-32-bytes", time.Second)
	if err != nil {
		t.Fatal(err)
	}
	event := outbox.Event{ID: "10000000-0000-0000-0000-000000000001", EventType: "alert.webhook_requested", Payload: json.RawMessage(`{}`)}
	if err = processor.Handle(context.Background(), event); !outbox.IsRetryable(err) {
		t.Fatalf("503 error should be retryable: %v", err)
	}
	disabled, err := NewProcessor("", "", time.Second)
	if err != nil || disabled.Handle(context.Background(), event) != nil {
		t.Fatalf("disabled processor err=%v", err)
	}
	if _, err = NewProcessor(server.URL, "short", time.Second); err == nil {
		t.Fatal("short signing secret was accepted")
	}
}

func TestProcessorRequiresConfigurationForDeliveryTest(t *testing.T) {
	t.Parallel()
	processor, err := NewProcessor("", "", time.Second)
	if err != nil {
		t.Fatal(err)
	}
	testEvent := outbox.Event{ID: "10000000-0000-0000-0000-000000000001", EventType: "alert.webhook_test_requested", Payload: json.RawMessage(`{}`)}
	if err = processor.Handle(context.Background(), testEvent); err == nil || outbox.IsRetryable(err) {
		t.Fatalf("expected a permanent configuration error, got %v", err)
	}
	regularEvent := outbox.Event{ID: testEvent.ID, EventType: "alert.webhook_requested", Payload: testEvent.Payload}
	if err = processor.Handle(context.Background(), regularEvent); err != nil {
		t.Fatalf("regular alert delivery must remain disabled-safe: %v", err)
	}
}