package token

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

	"atcr.io/pkg/auth"
)

// A read-only app password is a permanent authorization failure, not an outage.
// Returning the generic 503 tells the client to retry a request that can never
// succeed and says nothing about what is wrong; the fix is only discoverable by
// reading appview logs the user does not have.
//
// This is the sibling of TestHandler_ServiceAuthFetcher_FailureReturns503: same
// path, same stub, and the only difference is which error the fetcher reports.
func TestHandler_ServiceAuthFetcher_InsufficientScopeReturns403(t *testing.T) {
	keyPath := getSharedTestKey(t)
	issuer, err := NewIssuer(keyPath, "atcr.io", "registry", 5*time.Minute)
	if err != nil {
		t.Fatalf("NewIssuer() error = %v", err)
	}

	deviceStore, database := setupTestDeviceStore(t)
	deviceSecret := createTestDevice(t, deviceStore, database, "did:plc:alice123", "alice.bsky.social")

	handler := NewHandler(issuer, deviceStore)
	// Wrapped, not bare: the production path returns
	// fmt.Errorf("%w: %s", ErrAppPasswordInsufficientScope, body), so a handler
	// that compared with == instead of errors.Is would still 503.
	stub := &stubServiceAuthFetcher{
		err: fmt.Errorf("%w: %s", auth.ErrAppPasswordInsufficientScope,
			`{"error":"InsufficientScope","message":"Bad token scope"}`),
	}
	handler.SetServiceAuthFetcher(stub)

	req := httptest.NewRequest(http.MethodGet, "/auth/token?service=registry&scope=repository:alice.bsky.social/myapp:pull,push", nil)
	req.SetBasicAuth("alice", deviceSecret)
	w := httptest.NewRecorder()

	handler.ServeHTTP(w, req)

	if w.Code != http.StatusForbidden {
		t.Fatalf("expected 403 for an under-scoped app password, got %d. Body: %s", w.Code, w.Body.String())
	}

	// The status alone is not the deliverable: the body has to name the remedy,
	// because "app password" and "read-only" are the only words that tell the
	// user what to change.
	var body struct {
		Errors []struct {
			Code    string `json:"code"`
			Message string `json:"message"`
		} `json:"errors"`
	}
	if err := json.NewDecoder(w.Body).Decode(&body); err != nil {
		t.Fatalf("decode error response: %v", err)
	}
	if len(body.Errors) == 0 {
		t.Fatal("expected an OCI error payload, got none")
	}
	if body.Errors[0].Code != "DENIED" {
		t.Errorf("expected error code DENIED, got %q", body.Errors[0].Code)
	}
	msg := strings.ToLower(body.Errors[0].Message)
	for _, want := range []string{"app password", "read-only"} {
		if !strings.Contains(msg, want) {
			t.Errorf("error message does not mention %q, so it does not tell the user what to fix: %q", want, body.Errors[0].Message)
		}
	}
}