// Copyright (c) 2025-2026 Probo Inc <hello@probo.com>.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

package saml

import (
	"encoding/base64"
	"fmt"

	"github.com/crewjam/saml"
	"go.probo.inc/probo/pkg/coredata"
)

func (s *Service) serviceProvider(
	config *coredata.SAMLConfiguration,
) (*saml.ServiceProvider, error) {
	cert, err := config.GetIdPCertificate()
	if err != nil {
		return nil, fmt.Errorf("cannot parse IdP certificate: %w", err)
	}

	sp := s.baseServiceProvider()
	sp.IDPMetadata = &saml.EntityDescriptor{
		EntityID: config.IdPEntityID,
		IDPSSODescriptors: []saml.IDPSSODescriptor{
			{
				SSODescriptor: saml.SSODescriptor{
					RoleDescriptor: saml.RoleDescriptor{
						ProtocolSupportEnumeration: "urn:oasis:names:tc:SAML:2.0:protocol",
						KeyDescriptors: []saml.KeyDescriptor{
							{
								Use: "signing",
								KeyInfo: saml.KeyInfo{
									X509Data: saml.X509Data{
										X509Certificates: []saml.X509Certificate{
											{Data: base64.StdEncoding.EncodeToString(cert.Raw)},
										},
									},
								},
							},
						},
					},
					NameIDFormats: []saml.NameIDFormat{
						saml.EmailAddressNameIDFormat,
					},
				},
				SingleSignOnServices: []saml.Endpoint{
					{
						Binding:  saml.HTTPRedirectBinding,
						Location: config.IdPSsoURL,
					},
				},
			},
		},
	}

	return sp, nil
}