package taskapi

import (
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"gitea.perlbach24.de/scripte/nexarch/common/policyclient"
)

// Steht fuer Core's POST /authorize-Vertrag ({"allowed": bool}); prueft die
// echte Kette requireAuth -> policyclient -> 403/next, nicht nur einen
// Datenbankeintrag. Die Ablehnungsfaelle brauchen keinen Store (nil), weil
// die Pruefung vor jedem Zugriff greifen muss.
func newFakePolicyAPI(t *testing.T, allow bool, seen *[]map[string]string) *httptest.Server {
	t.Helper()
	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path != "/authorize" || r.Header.Get("X-Service-Token") == "" {
			t.Fatalf("unerwartete anfrage: %s %s", r.Method, r.URL.Path)
		}
		var body map[string]string
		_ = json.NewDecoder(r.Body).Decode(&body)
		if seen != nil {
			*seen = append(*seen, body)
		}
		w.Header().Set("Content-Type", "application/json")
		_ = json.NewEncoder(w).Encode(map[string]bool{"allowed": allow})
	}))
}

func policyMux(t *testing.T, policyURL string) *http.ServeMux {
	t.Helper()
	mux := http.NewServeMux()
	NewServer(nil, "acme").WithPolicy(policyclient.New(policyURL, "test-token")).RegisterRoutes(mux)
	return mux
}

func authed(req *http.Request) *http.Request {
	req.Header.Set("X-User-Id", "u1")
	req.Header.Set("X-Tenant-Slug", "acme")
	return req
}

func TestHandleList_PolicyDenies_Rejected(t *testing.T) {
	var seen []map[string]string
	policyAPI := newFakePolicyAPI(t, false, &seen)
	defer policyAPI.Close()
	mux := policyMux(t, policyAPI.URL)

	rec := httptest.NewRecorder()
	mux.ServeHTTP(rec, authed(httptest.NewRequest(http.MethodGet, "/tasks", nil)))
	if rec.Code != http.StatusForbidden {
		t.Fatalf("erwartet 403 ohne berechtigung, bekam %d: %s", rec.Code, rec.Body.String())
	}
	if len(seen) != 1 || seen[0]["permission"] != "workflow.task.read" || seen[0]["tenant"] != "acme" {
		t.Fatalf("falsche policy-anfrage: %+v", seen)
	}
}

func TestHandleSetStatus_PolicyDenies_Rejected(t *testing.T) {
	var seen []map[string]string
	policyAPI := newFakePolicyAPI(t, false, &seen)
	defer policyAPI.Close()
	mux := policyMux(t, policyAPI.URL)

	req := authed(httptest.NewRequest(http.MethodPatch, "/tasks/t-1/status", strings.NewReader(`{"status":"done"}`)))
	rec := httptest.NewRecorder()
	mux.ServeHTTP(rec, req)
	if rec.Code != http.StatusForbidden {
		t.Fatalf("erwartet 403 ohne berechtigung, bekam %d: %s", rec.Code, rec.Body.String())
	}
	if len(seen) != 1 || seen[0]["permission"] != "workflow.task.write" {
		t.Fatalf("falsche policy-anfrage: %+v", seen)
	}
}

func TestHandleList_PolicyUnavailable_FailsClosed(t *testing.T) {
	policyAPI := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusInternalServerError)
	}))
	defer policyAPI.Close()
	mux := policyMux(t, policyAPI.URL)

	rec := httptest.NewRecorder()
	mux.ServeHTTP(rec, authed(httptest.NewRequest(http.MethodGet, "/tasks", nil)))
	if rec.Code != http.StatusServiceUnavailable {
		t.Fatalf("erwartet 503 bei ausfall des berechtigungsdienstes, bekam %d", rec.Code)
	}
}

func TestHandleList_PolicyNotAskedWithoutIdentity(t *testing.T) {
	var seen []map[string]string
	policyAPI := newFakePolicyAPI(t, true, &seen)
	defer policyAPI.Close()
	mux := policyMux(t, policyAPI.URL)

	rec := httptest.NewRecorder()
	mux.ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/tasks", nil))
	if rec.Code != http.StatusUnauthorized {
		t.Fatalf("erwartet 401 ohne identitaet, bekam %d", rec.Code)
	}
	if len(seen) != 0 {
		t.Fatalf("policy darf ohne identitaet nicht befragt werden: %+v", seen)
	}
}

func TestHandleList_PolicyAllows_Passes(t *testing.T) {
	srv, _ := newTestServer(t)
	policyAPI := newFakePolicyAPI(t, true, nil)
	defer policyAPI.Close()
	mux := http.NewServeMux()
	srv.WithPolicy(policyclient.New(policyAPI.URL, "test-token")).RegisterRoutes(mux)

	rec := httptest.NewRecorder()
	mux.ServeHTTP(rec, authed(httptest.NewRequest(http.MethodGet, "/tasks", nil)))
	if rec.Code != http.StatusOK {
		t.Fatalf("erwartet 200 mit berechtigung, bekam %d: %s", rec.Code, rec.Body.String())
	}
}

func TestPolicyAsked_WithRoleFromHeader_DefaultUser(t *testing.T) {
	var seen []map[string]string
	policyAPI := newFakePolicyAPI(t, false, &seen)
	defer policyAPI.Close()
	mux := policyMux(t, policyAPI.URL)

	mux.ServeHTTP(httptest.NewRecorder(), authed(httptest.NewRequest(http.MethodGet, "/tasks", nil)))
	admin := authed(httptest.NewRequest(http.MethodGet, "/tasks", nil))
	admin.Header.Set("X-User-Role", "tenant_admin")
	mux.ServeHTTP(httptest.NewRecorder(), admin)

	if len(seen) != 2 || seen[0]["role"] != "user" || seen[1]["role"] != "tenant_admin" {
		t.Fatalf("falsche rollen in policy-anfragen: %+v", seen)
	}
}