package managerconfig

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

	"git.118im.com/im_team/im_workbench/internal/config"
)

func TestResolveUIDKeyPrefersManager(t *testing.T) {
	const secret = "test-secret"
	const managerKey = "manager-key"
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path != "/internal/im-config/third-party/im" {
			t.Fatalf("unexpected path %s", r.URL.Path)
		}
		if r.URL.Query().Get("keys") != "uid_encryption_key,UID_ENCRYPTION_KEY,uid_key" {
			t.Fatalf("unexpected keys %s", r.URL.Query().Get("keys"))
		}
		if r.Header.Get("X-Service-Name") != "im-workbench" {
			t.Fatalf("unexpected service %s", r.Header.Get("X-Service-Name"))
		}
		if !validSignature(t, r, secret) {
			t.Fatal("invalid signature")
		}
		_, _ = w.Write([]byte(`{"code":0,"data":{"values":{"uid_encryption_key":"manager-key"}}}`))
	}))
	defer server.Close()

	got := ResolveUIDKey(context.Background(), config.ManagerConfig{
		BaseURL:     server.URL,
		ServiceName: "im-workbench",
		Secret:      secret,
		UIDKeyGroup: "im",
		UIDKeyKeys:  []string{"uid_encryption_key", "UID_ENCRYPTION_KEY", "uid_key"},
	}, "fallback-key")
	if got != managerKey {
		t.Fatalf("ResolveUIDKey() = %q, want %q", got, managerKey)
	}
}

func TestResolveUIDKeyFallsBack(t *testing.T) {
	got := ResolveUIDKey(context.Background(), config.ManagerConfig{}, "fallback-key")
	if got != "fallback-key" {
		t.Fatalf("ResolveUIDKey() = %q, want fallback", got)
	}
}

func TestParseValuesAcceptsUnwrappedResponse(t *testing.T) {
	values, err := parseValues([]byte(`{"values":{"UID_ENCRYPTION_KEY":"key"}}`))
	if err != nil {
		t.Fatal(err)
	}
	if values["UID_ENCRYPTION_KEY"] != "key" {
		t.Fatalf("unexpected values %#v", values)
	}
}

func validSignature(t *testing.T, r *http.Request, secret string) bool {
	t.Helper()
	body, err := io.ReadAll(r.Body)
	if err != nil {
		t.Fatal(err)
	}
	bodyHash := sha256.Sum256(body)
	signingText := strings.Join([]string{
		r.Method,
		r.URL.RequestURI(),
		hex.EncodeToString(bodyHash[:]),
		r.Header.Get("X-Timestamp"),
		r.Header.Get("X-Nonce"),
	}, "\n")
	mac := hmac.New(sha256.New, []byte(secret))
	_, _ = mac.Write([]byte(signingText))
	return hmac.Equal([]byte(r.Header.Get("X-Signature")), []byte(hex.EncodeToString(mac.Sum(nil))))
}