/**
 *    Copyright (c) 2022-2023 Project CHIP Authors
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

#import <Matter/Matter.h>

// system dependencies
#import <XCTest/XCTest.h>

#import "MTRTestKeys.h"

@interface MTRCertificateTests : XCTestCase

@end

@implementation MTRCertificateTests

/**
 * Helper function for creating start dates rounded to the nearest second (and
 * which can therefore be represented without data loss in certificates).
 */
+ (NSDate *)startDateWithTimeIntervalSinceNow:(NSTimeInterval)interval
{
    __auto_type * startDate = [NSDate dateWithTimeIntervalSinceNow:interval];
    // Round down to the nearest second, since the certificate bits will do that
    // when they compute validity dates.
    NSTimeInterval seconds = floor([startDate timeIntervalSinceReferenceDate]);
    return [NSDate dateWithTimeIntervalSinceReferenceDate:seconds];
}

- (void)testGenerateRootCert
{
    __auto_type * testKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(testKeys);

    __auto_type * rootCert = [MTRCertificates createRootCertificate:testKeys issuerID:nil fabricID:nil error:nil];
    XCTAssertNotNil(rootCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:rootCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(rootCert, derCert);
}

- (void)testGenerateRootCertWithValidityPeriod
{
    __auto_type * testKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(testKeys);

    __auto_type * startDate = [MTRCertificateTests startDateWithTimeIntervalSinceNow:100];
    __auto_type * validityPeriod = [[NSDateInterval alloc] initWithStartDate:startDate duration:200];

    __auto_type * rootCert = [MTRCertificates createRootCertificate:testKeys
                                                           issuerID:nil
                                                           fabricID:nil
                                                     validityPeriod:validityPeriod
                                                              error:nil];
    XCTAssertNotNil(rootCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:rootCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(rootCert, derCert);

    __auto_type * certInfo = [[MTRCertificateInfo alloc] initWithTLVBytes:tlvCert];
    XCTAssertEqualObjects(validityPeriod.startDate, certInfo.notBefore);
    XCTAssertEqualObjects(validityPeriod.endDate, certInfo.notAfter);
}

- (void)testGenerateRootCertWithInfiniteValidity
{
    __auto_type * testKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(testKeys);

    __auto_type * startDate = [MTRCertificateTests startDateWithTimeIntervalSinceNow:100];
    __auto_type * validityPeriod = [[NSDateInterval alloc] initWithStartDate:startDate endDate:[NSDate distantFuture]];

    __auto_type * rootCert = [MTRCertificates createRootCertificate:testKeys
                                                           issuerID:nil
                                                           fabricID:nil
                                                     validityPeriod:validityPeriod
                                                              error:nil];
    XCTAssertNotNil(rootCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:rootCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(rootCert, derCert);

    __auto_type * certInfo = [[MTRCertificateInfo alloc] initWithTLVBytes:tlvCert];
    XCTAssertEqualObjects(validityPeriod.startDate, certInfo.notBefore);
    XCTAssertEqualObjects(validityPeriod.endDate, certInfo.notAfter);
}

- (void)testGenerateIntermediateCert
{
    __auto_type * rootKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(rootKeys);

    __auto_type * rootCert = [MTRCertificates createRootCertificate:rootKeys issuerID:nil fabricID:nil error:nil];
    XCTAssertNotNil(rootCert);

    __auto_type * intermediateKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(intermediateKeys);

    __auto_type * intermediateCert = [MTRCertificates createIntermediateCertificate:rootKeys
                                                                    rootCertificate:rootCert
                                                              intermediatePublicKey:intermediateKeys.publicKey
                                                                           issuerID:nil
                                                                           fabricID:nil
                                                                              error:nil];
    XCTAssertNotNil(intermediateCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:intermediateCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(intermediateCert, derCert);
}

- (void)testGenerateIntermediateCertWithValidityPeriod
{
    __auto_type * rootKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(rootKeys);

    __auto_type * rootCert = [MTRCertificates createRootCertificate:rootKeys issuerID:nil fabricID:nil error:nil];
    XCTAssertNotNil(rootCert);

    __auto_type * intermediateKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(intermediateKeys);

    __auto_type * startDate = [MTRCertificateTests startDateWithTimeIntervalSinceNow:300];
    __auto_type * validityPeriod = [[NSDateInterval alloc] initWithStartDate:startDate duration:400];

    __auto_type * intermediateCert = [MTRCertificates createIntermediateCertificate:rootKeys
                                                                    rootCertificate:rootCert
                                                              intermediatePublicKey:intermediateKeys.publicKey
                                                                           issuerID:nil
                                                                           fabricID:nil
                                                                     validityPeriod:validityPeriod
                                                                              error:nil];
    XCTAssertNotNil(intermediateCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:intermediateCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(intermediateCert, derCert);

    __auto_type * certInfo = [[MTRCertificateInfo alloc] initWithTLVBytes:tlvCert];
    XCTAssertEqualObjects(validityPeriod.startDate, certInfo.notBefore);
    XCTAssertEqualObjects(validityPeriod.endDate, certInfo.notAfter);
}

- (void)testGenerateIntermediateCertWithInfiniteValidity
{
    __auto_type * rootKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(rootKeys);

    __auto_type * rootCert = [MTRCertificates createRootCertificate:rootKeys issuerID:nil fabricID:nil error:nil];
    XCTAssertNotNil(rootCert);

    __auto_type * intermediateKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(intermediateKeys);

    __auto_type * startDate = [MTRCertificateTests startDateWithTimeIntervalSinceNow:300];
    __auto_type * validityPeriod = [[NSDateInterval alloc] initWithStartDate:startDate endDate:[NSDate distantFuture]];

    __auto_type * intermediateCert = [MTRCertificates createIntermediateCertificate:rootKeys
                                                                    rootCertificate:rootCert
                                                              intermediatePublicKey:intermediateKeys.publicKey
                                                                           issuerID:nil
                                                                           fabricID:nil
                                                                     validityPeriod:validityPeriod
                                                                              error:nil];
    XCTAssertNotNil(intermediateCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:intermediateCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(intermediateCert, derCert);

    __auto_type * certInfo = [[MTRCertificateInfo alloc] initWithTLVBytes:tlvCert];
    XCTAssertEqualObjects(validityPeriod.startDate, certInfo.notBefore);
    XCTAssertEqualObjects(validityPeriod.endDate, certInfo.notAfter);
}

- (void)testGenerateOperationalCertNoIntermediate
{
    __auto_type * rootKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(rootKeys);

    __auto_type * rootCert = [MTRCertificates createRootCertificate:rootKeys issuerID:nil fabricID:nil error:nil];
    XCTAssertNotNil(rootCert);

    __auto_type * operationalKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(operationalKeys);

    __auto_type * cats = [[NSMutableSet alloc] initWithCapacity:3];
    // High bits are identifier, low bits are version.
    [cats addObject:@0x00010001];
    [cats addObject:@0x00020001];
    [cats addObject:@0x0003FFFF];

    __auto_type * operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                               signingCertificate:rootCert
                                                             operationalPublicKey:operationalKeys.publicKey
                                                                         fabricID:@1
                                                                           nodeID:@1
                                                            caseAuthenticatedTags:cats
                                                                            error:nil];
    XCTAssertNotNil(operationalCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:operationalCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(operationalCert, derCert);
}

- (void)testGenerateOperationalCertNoIntermediateWithValidityPeriod
{
    __auto_type * rootKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(rootKeys);

    __auto_type * rootCert = [MTRCertificates createRootCertificate:rootKeys issuerID:nil fabricID:nil error:nil];
    XCTAssertNotNil(rootCert);

    __auto_type * operationalKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(operationalKeys);

    __auto_type * cats = [[NSMutableSet alloc] initWithCapacity:3];
    // High bits are identifier, low bits are version.
    [cats addObject:@0x00010001];
    [cats addObject:@0x00020001];
    [cats addObject:@0x0003FFFF];

    __auto_type * startDate = [MTRCertificateTests startDateWithTimeIntervalSinceNow:1000];
    __auto_type * validityPeriod = [[NSDateInterval alloc] initWithStartDate:startDate duration:500];

    __auto_type * operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                               signingCertificate:rootCert
                                                             operationalPublicKey:operationalKeys.publicKey
                                                                         fabricID:@1
                                                                           nodeID:@1
                                                            caseAuthenticatedTags:cats
                                                                   validityPeriod:validityPeriod
                                                                            error:nil];
    XCTAssertNotNil(operationalCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:operationalCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(operationalCert, derCert);

    __auto_type * certInfo = [[MTRCertificateInfo alloc] initWithTLVBytes:tlvCert];
    XCTAssertEqualObjects(validityPeriod.startDate, certInfo.notBefore);
    XCTAssertEqualObjects(validityPeriod.endDate, certInfo.notAfter);
}

- (void)testGenerateOperationalCertNoIntermediateWithInfiniteValidity
{
    __auto_type * rootKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(rootKeys);

    __auto_type * rootCert = [MTRCertificates createRootCertificate:rootKeys issuerID:nil fabricID:nil error:nil];
    XCTAssertNotNil(rootCert);

    __auto_type * operationalKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(operationalKeys);

    __auto_type * cats = [[NSMutableSet alloc] initWithCapacity:3];
    // High bits are identifier, low bits are version.
    [cats addObject:@0x00010001];
    [cats addObject:@0x00020001];
    [cats addObject:@0x0003FFFF];

    __auto_type * startDate = [MTRCertificateTests startDateWithTimeIntervalSinceNow:1000];
    __auto_type * validityPeriod = [[NSDateInterval alloc] initWithStartDate:startDate endDate:[NSDate distantFuture]];

    __auto_type * operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                               signingCertificate:rootCert
                                                             operationalPublicKey:operationalKeys.publicKey
                                                                         fabricID:@1
                                                                           nodeID:@1
                                                            caseAuthenticatedTags:cats
                                                                   validityPeriod:validityPeriod
                                                                            error:nil];
    XCTAssertNotNil(operationalCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:operationalCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(operationalCert, derCert);

    __auto_type * certInfo = [[MTRCertificateInfo alloc] initWithTLVBytes:tlvCert];
    XCTAssertEqualObjects(validityPeriod.startDate, certInfo.notBefore);
    XCTAssertEqualObjects(validityPeriod.endDate, certInfo.notAfter);
}

- (void)testGenerateOperationalCertWithIntermediate
{
    __auto_type * rootKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(rootKeys);

    __auto_type * rootCert = [MTRCertificates createRootCertificate:rootKeys issuerID:nil fabricID:nil error:nil];
    XCTAssertNotNil(rootCert);

    __auto_type * intermediateKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(intermediateKeys);

    __auto_type * intermediateCert = [MTRCertificates createIntermediateCertificate:rootKeys
                                                                    rootCertificate:rootCert
                                                              intermediatePublicKey:intermediateKeys.publicKey
                                                                           issuerID:nil
                                                                           fabricID:nil
                                                                              error:nil];
    XCTAssertNotNil(intermediateCert);

    __auto_type * operationalKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(operationalKeys);

    __auto_type * operationalCert = [MTRCertificates createOperationalCertificate:intermediateKeys
                                                               signingCertificate:intermediateCert
                                                             operationalPublicKey:operationalKeys.publicKey
                                                                         fabricID:@1
                                                                           nodeID:@1
                                                            caseAuthenticatedTags:nil
                                                                            error:nil];
    XCTAssertNotNil(operationalCert);

    // Test round-trip through TLV format.
    __auto_type * tlvCert = [MTRCertificates convertX509Certificate:operationalCert];
    XCTAssertNotNil(tlvCert);

    __auto_type * derCert = [MTRCertificates convertMatterCertificate:tlvCert];
    XCTAssertNotNil(derCert);

    XCTAssertEqualObjects(operationalCert, derCert);
}

- (void)testGenerateOperationalCertErrorCases
{
    __auto_type * rootKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(rootKeys);

    __auto_type * rootCert = [MTRCertificates createRootCertificate:rootKeys issuerID:nil fabricID:nil error:nil];
    XCTAssertNotNil(rootCert);

    __auto_type * operationalKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(operationalKeys);

    __auto_type * longCats = [[NSMutableSet alloc] initWithCapacity:4];
    [longCats addObject:@0x00010001];
    [longCats addObject:@0x00020001];
    [longCats addObject:@0x00030001];
    [longCats addObject:@0x00040001];

    __auto_type * catsWithSameIdentifier = [[NSMutableSet alloc] initWithCapacity:3];
    // High bits are identifier, low bits are version.
    [catsWithSameIdentifier addObject:@0x00010001];
    [catsWithSameIdentifier addObject:@0x00020001];
    [catsWithSameIdentifier addObject:@0x00010002];

    __auto_type * catsWithInvalidVersion = [[NSMutableSet alloc] initWithCapacity:2];
    // High bits are identifier, low bits are version.
    [catsWithInvalidVersion addObject:@0x00010001];
    [catsWithInvalidVersion addObject:@0x00020000];

    // Check basic case works
    __auto_type * operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                               signingCertificate:rootCert
                                                             operationalPublicKey:operationalKeys.publicKey
                                                                         fabricID:@1
                                                                           nodeID:@1
                                                            caseAuthenticatedTags:nil
                                                                            error:nil];
    XCTAssertNotNil(operationalCert);

    // CATs too long
    operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                 signingCertificate:rootCert
                                               operationalPublicKey:operationalKeys.publicKey
                                                           fabricID:@1
                                                             nodeID:@1
                                              caseAuthenticatedTags:longCats
                                                              error:nil];
    XCTAssertNil(operationalCert);

    // Multiple CATs with the same identifier but different versions
    operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                 signingCertificate:rootCert
                                               operationalPublicKey:operationalKeys.publicKey
                                                           fabricID:@1
                                                             nodeID:@1
                                              caseAuthenticatedTags:catsWithSameIdentifier
                                                              error:nil];
    XCTAssertNil(operationalCert);

    // CAT with invalid version
    operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                 signingCertificate:rootCert
                                               operationalPublicKey:operationalKeys.publicKey
                                                           fabricID:@1
                                                             nodeID:@1
                                              caseAuthenticatedTags:catsWithInvalidVersion
                                                              error:nil];
    XCTAssertNil(operationalCert);

    // Signing key mismatch
    operationalCert = [MTRCertificates createOperationalCertificate:operationalKeys
                                                 signingCertificate:rootCert
                                               operationalPublicKey:operationalKeys.publicKey
                                                           fabricID:@1
                                                             nodeID:@1
                                              caseAuthenticatedTags:nil
                                                              error:nil];
    XCTAssertNil(operationalCert);

    // Invalid fabric id
    operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                 signingCertificate:rootCert
                                               operationalPublicKey:operationalKeys.publicKey
                                                           fabricID:@0
                                                             nodeID:@1
                                              caseAuthenticatedTags:nil
                                                              error:nil];
    XCTAssertNil(operationalCert);

    // Undefined node id
    operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                 signingCertificate:rootCert
                                               operationalPublicKey:operationalKeys.publicKey
                                                           fabricID:@1
                                                             nodeID:@0
                                              caseAuthenticatedTags:nil
                                                              error:nil];
    XCTAssertNil(operationalCert);

    // Non-operational node id
    operationalCert = [MTRCertificates createOperationalCertificate:rootKeys
                                                 signingCertificate:rootCert
                                               operationalPublicKey:operationalKeys.publicKey
                                                           fabricID:@1
                                                             nodeID:@(0xFFFFFFFFFFFFFFFFLLU)
                                              caseAuthenticatedTags:nil
                                                              error:nil];
    XCTAssertNil(operationalCert);
}

- (void)testGenerateCSR
{
    __auto_type * testKeys = [[MTRTestKeys alloc] init];
    XCTAssertNotNil(testKeys);

    __auto_type * csr = [MTRCertificates createCertificateSigningRequest:testKeys error:nil];
    XCTAssertNotNil(csr);

    __auto_type * publicKey = [MTRCertificates publicKeyFromCSR:csr error:nil];
    XCTAssertNotNil(publicKey);

    SecKeyRef originalKeyRef = [testKeys publicKey];
    XCTAssertTrue(originalKeyRef != NULL);

    NSData * originalPublicKey = (__bridge_transfer NSData *) SecKeyCopyExternalRepresentation(originalKeyRef, nil);
    XCTAssertNotNil(originalPublicKey);

    XCTAssertEqualObjects(publicKey, originalPublicKey);
}

@end