GTCredential.m

//
//  GTCredential.m
//  ObjectiveGitFramework
//
//  Created by Etienne on 10/09/13.
//  Copyright (c) 2013 GitHub, Inc. All rights reserved.
//

#import "GTCredential.h"
#import "GTCredential+Private.h"
#import "NSError+Git.h"

#import "git2/errors.h"

typedef GTCredential *(^GTCredentialProviderBlock)(GTCredentialType allowedTypes, NSString *URL, NSString *userName);

@interface GTCredentialProvider ()
@property (nonatomic, readonly, copy) GTCredentialProviderBlock credBlock;
@end

@implementation GTCredentialProvider

+ (instancetype)providerWithBlock:(GTCredentialProviderBlock)credentialBlock {
	NSParameterAssert(credentialBlock != nil);

	GTCredentialProvider *provider = [[self alloc] init];

	provider->_credBlock = [credentialBlock copy];

	return provider;
}

- (GTCredential *)credentialForType:(GTCredentialType)type URL:(NSString *)URL userName:(NSString *)userName {
	NSAssert(self.credBlock != nil, @"Provider asked for credentials without block being set.");

	return self.credBlock(type, URL, userName);
}

@end

@interface GTCredential ()
@property (nonatomic, assign, readonly) git_cred *git_cred;
@end

@implementation GTCredential

+ (instancetype)credentialWithUserName:(NSString *)userName password:(NSString *)password error:(NSError **)error {
	git_cred *cred;
	int gitError = git_cred_userpass_plaintext_new(&cred, userName.UTF8String, password.UTF8String);
	if (gitError != GIT_OK) {
		if (error) *error = [NSError git_errorFor:gitError description:@"Failed to create credentials object" failureReason:@"There was an error creating a credential object for username %@.", userName];
		return nil;
	}

	return [[self alloc] initWithGitCred:cred];
}

+ (instancetype)credentialWithUserName:(NSString *)userName publicKeyURL:(NSURL *)publicKeyURL privateKeyURL:(NSURL *)privateKeyURL passphrase:(NSString *)passphrase error:(NSError **)error {
	NSParameterAssert(privateKeyURL != nil);
	NSString *publicKeyPath = publicKeyURL.filePathURL.path;
	NSString *privateKeyPath = privateKeyURL.filePathURL.path;
	NSAssert(privateKeyPath != nil, @"Invalid file URL passed: %@", privateKeyURL);

	git_cred *cred;
	int gitError = git_cred_ssh_key_new(&cred, userName.UTF8String, publicKeyPath.fileSystemRepresentation, privateKeyPath.fileSystemRepresentation, passphrase.UTF8String);
	if (gitError != GIT_OK) {
		if (error) *error = [NSError git_errorFor:gitError description:@"Failed to create credentials object" failureReason:@"There was an error creating a credential object for username %@ with the provided public/private key pair.\nPublic key: %@\nPrivate key: %@", userName, publicKeyURL, privateKeyURL];
		return nil;
	}

	return [[self alloc] initWithGitCred:cred];
}

+ (instancetype)credentialWithUserName:(NSString *)userName publicKeyString:(NSString *)publicKeyString privateKeyString:(NSString *)privateKeyString passphrase:(NSString *)passphrase error:(NSError **)error {
	NSParameterAssert(privateKeyString != nil);
	
	git_cred *cred;
	int gitError = git_cred_ssh_key_memory_new(&cred, userName.UTF8String, publicKeyString.UTF8String, privateKeyString.UTF8String, passphrase.UTF8String);
	if (gitError != GIT_OK) {
		if (error) *error = [NSError git_errorFor:gitError description:@"Failed to create credentials object" failureReason:@"There was an error creating a credential object for username %@ with the provided public/private key pair.\nPublic key: %@", userName, publicKeyString];
		return nil;
	}
	
	return [[self alloc] initWithGitCred:cred];
}

- (instancetype)initWithGitCred:(git_cred *)cred {
	NSParameterAssert(cred != nil);
	self = [self init];

	if (self == nil) return nil;

	_git_cred = cred;

	return self;
}

@end

int GTCredentialAcquireCallback(git_cred **git_cred, const char *url, const char *username_from_url, unsigned int allowed_types, void *payload) {
	NSCParameterAssert(git_cred != NULL);
	NSCParameterAssert(payload != NULL);

	GTCredentialAcquireCallbackInfo *info = payload;
	GTCredentialProvider *provider = info->credProvider;

	if (provider == nil) {
		git_error_set_str(GIT_EUSER, "No GTCredentialProvider set, but authentication was requested.");
		return GIT_ERROR;
	}

	NSString *URL = (url != NULL ? @(url) : @"");
	NSString *userName = (username_from_url != NULL ? @(username_from_url) : nil);

	GTCredential *cred = [provider credentialForType:(GTCredentialType)allowed_types URL:URL userName:userName];
	if (cred == nil) {
		git_error_set_str(GIT_EUSER, "GTCredentialProvider failed to provide credentials.");
		return GIT_ERROR;
	}

	*git_cred = cred.git_cred;
	return GIT_OK;
}