package notifyapi

import (
	"bytes"
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"os"
	"testing"

	"github.com/jackc/pgx/v5/pgxpool"

	"gitea.perlbach24.de/scripte/nexarch/internal/notify"
	"gitea.perlbach24.de/scripte/nexarch/internal/notifyprefs"
)

const testToken = "test-service-token-cfg05"

func setupTest(t *testing.T) (*notifyprefs.Store, *notify.Dispatcher, *pgxpool.Pool) {
	t.Helper()
	dsn := os.Getenv("TEST_ADMIN_DSN")
	if dsn == "" {
		t.Skip("TEST_ADMIN_DSN nicht gesetzt, Integrationstest uebersprungen")
	}
	ctx := context.Background()
	pool, err := pgxpool.New(ctx, dsn)
	if err != nil {
		t.Fatalf("pool: %v", err)
	}
	t.Cleanup(func() { pool.Close() })

	if _, err := pool.Exec(ctx, `
		CREATE TABLE IF NOT EXISTS notification_preferences (
			tenant_slug TEXT NOT NULL, user_id TEXT NOT NULL, event_type TEXT NOT NULL, channel TEXT NOT NULL,
			enabled BOOLEAN NOT NULL, updated_at TIMESTAMPTZ NOT NULL DEFAULT now(),
			PRIMARY KEY (tenant_slug, user_id, event_type, channel)
		);
		CREATE TABLE IF NOT EXISTS notification_jobs (
			id UUID PRIMARY KEY DEFAULT gen_random_uuid(), channel TEXT NOT NULL, recipient TEXT NOT NULL,
			payload JSONB NOT NULL DEFAULT '{}'::jsonb, status TEXT NOT NULL DEFAULT 'pending', attempts INT NOT NULL DEFAULT 0,
			max_attempts INT NOT NULL DEFAULT 5, next_attempt_at TIMESTAMPTZ NOT NULL DEFAULT now(), last_error TEXT,
			created_at TIMESTAMPTZ NOT NULL DEFAULT now(), updated_at TIMESTAMPTZ NOT NULL DEFAULT now()
		);
	`); err != nil {
		t.Fatalf("schema: %v", err)
	}
	t.Cleanup(func() {
		_, _ = pool.Exec(context.Background(), `DELETE FROM notification_jobs WHERE recipient LIKE 'cfg05\_%' ESCAPE '\'`)
		_, _ = pool.Exec(context.Background(), `DELETE FROM notification_preferences WHERE user_id LIKE 'cfg05\_%' ESCAPE '\'`)
	})

	return notifyprefs.NewStore(pool), notify.NewDispatcher(pool), pool
}

func post(t *testing.T, server *httptest.Server, token string, req enqueueRequest) *http.Response {
	t.Helper()
	body, _ := json.Marshal(req)
	httpReq, _ := http.NewRequest(http.MethodPost, server.URL+"/notify/enqueue", bytes.NewReader(body))
	if token != "" {
		httpReq.Header.Set("X-Service-Token", token)
	}
	resp, err := http.DefaultClient.Do(httpReq)
	if err != nil {
		t.Fatalf("post: %v", err)
	}
	return resp
}

// TestEnqueueHandler_MissingTokenReturns401 ist die geforderte
// Pflichtpruefung: Aufruf ohne Service-Token wird abgewiesen, Handler nie
// erreicht, keine Zustellung ausgeloest.
func TestEnqueueHandler_MissingTokenReturns401(t *testing.T) {
	prefs, dispatcher, _ := setupTest(t)
	mux := http.NewServeMux()
	Mount(mux, prefs, dispatcher, testToken)
	server := httptest.NewServer(mux)
	defer server.Close()

	resp := post(t, server, "", enqueueRequest{
		TenantSlug: "acme", UserID: "cfg05_user1", EventType: "invoice_ready", Channel: "email", Recipient: "cfg05_user1@acme.example",
	})
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusUnauthorized {
		t.Fatalf("ohne token: status = %d, want 401", resp.StatusCode)
	}
}

// TestEnqueueHandler_MatchesDirectEnqueueIfAllowed ist die geforderte
// Pflichtpruefung: Endpunkt-Verhalten stimmt exakt mit dem direkten
// EnqueueIfAllowed-Aufruf ueberein, real fuer aktivierten UND deaktivierten
// Kanal.
func TestEnqueueHandler_MatchesDirectEnqueueIfAllowed(t *testing.T) {
	prefs, dispatcher, _ := setupTest(t)
	mux := http.NewServeMux()
	Mount(mux, prefs, dispatcher, testToken)
	server := httptest.NewServer(mux)
	defer server.Close()

	ctx := context.Background()

	// Fall 1: kein explizites Preference -> Opt-out-Default aktiviert.
	resp1 := post(t, server, testToken, enqueueRequest{
		TenantSlug: "acme", UserID: "cfg05_user_enabled", EventType: "invoice_ready", Channel: "email", Recipient: "cfg05_user_enabled@acme.example",
	})
	defer func() { _ = resp1.Body.Close() }()
	if resp1.StatusCode != http.StatusOK {
		t.Fatalf("aktivierter fall: status = %d, want 200", resp1.StatusCode)
	}
	var out1 enqueueResponse
	if err := json.NewDecoder(resp1.Body).Decode(&out1); err != nil {
		t.Fatalf("antwort dekodieren: %v", err)
	}
	if out1.Skipped || out1.JobID == "" {
		t.Fatalf("erwartet zugestellt mit job-id, habe: %+v", out1)
	}

	// Fall 2: Kanal explizit deaktiviert -> muss uebereinstimmend skipped=true liefern,
	// wie ein direkter EnqueueIfAllowed-Aufruf es auch taete.
	if err := prefs.Set(ctx, "acme", "cfg05_user_disabled", "invoice_ready", "email", false); err != nil {
		t.Fatalf("praeferenz setzen: %v", err)
	}
	directJobID, directSkipped, err := notifyprefs.EnqueueIfAllowed(ctx, prefs, dispatcher, "acme", "cfg05_user_disabled", "invoice_ready", "email", "cfg05_user_disabled@acme.example", nil)
	if err != nil {
		t.Fatalf("direkter aufruf: %v", err)
	}

	resp2 := post(t, server, testToken, enqueueRequest{
		TenantSlug: "acme", UserID: "cfg05_user_disabled", EventType: "invoice_ready", Channel: "email", Recipient: "cfg05_user_disabled@acme.example",
	})
	defer func() { _ = resp2.Body.Close() }()
	var out2 enqueueResponse
	if err := json.NewDecoder(resp2.Body).Decode(&out2); err != nil {
		t.Fatalf("antwort dekodieren: %v", err)
	}
	if out2.Skipped != directSkipped {
		t.Fatalf("http skipped=%t weicht vom direkten aufruf skipped=%t ab", out2.Skipped, directSkipped)
	}
	if !out2.Skipped {
		t.Fatalf("deaktivierter kanal haette uebersprungen werden muessen, direkt=%q http=%q", directJobID, out2.JobID)
	}
}

// TestEnqueueHandler_RealForeignModuleClient simuliert einen Fremd-Modul-
// Testclient (z. B. Archive/RET-07), der real gegen den laufenden Endpunkt
// eine Benachrichtigung ausloest.
func TestEnqueueHandler_RealForeignModuleClient(t *testing.T) {
	prefs, dispatcher, pool := setupTest(t)
	mux := http.NewServeMux()
	Mount(mux, prefs, dispatcher, testToken)
	server := httptest.NewServer(mux)
	defer server.Close()

	resp := post(t, server, testToken, enqueueRequest{
		TenantSlug: "acme", UserID: "cfg05_fremd_modul", EventType: "retention_due_soon", Channel: "email", Recipient: "cfg05_fremd_modul@acme.example",
	})
	defer func() { _ = resp.Body.Close() }()
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("status = %d, want 200", resp.StatusCode)
	}
	var out enqueueResponse
	if err := json.NewDecoder(resp.Body).Decode(&out); err != nil {
		t.Fatalf("antwort dekodieren: %v", err)
	}
	if out.Skipped || out.JobID == "" {
		t.Fatalf("erwartet echte job-id, habe: %+v", out)
	}

	var count int
	if err := pool.QueryRow(context.Background(), `SELECT count(*) FROM notification_jobs WHERE id = $1`, out.JobID).Scan(&count); err != nil {
		t.Fatalf("job pruefen: %v", err)
	}
	if count != 1 {
		t.Fatalf("erwartet real angelegte notification_jobs-zeile fuer job-id %s", out.JobID)
	}
}