// disfluid, implementation of the Solid specification
// Copyright (C) 2020, 2021  Vivien Kraus

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.

// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <https://www.gnu.org/licenses/>.

#ifndef H_DISFLUID_INCLUDED
#define H_DISFLUID_INCLUDED

#include <stdlib.h>

/**
 * DisfluidApi:
 *
 * The context associated with the API is loaded when entering the
 * @disfluid_init function, and unloaded when the function exits.
 */
struct DisfluidApi;
typedef struct DisfluidApi DisfluidApi;

/**
 * DisfluidUser:
 *
 * @data: (closure):
 *
 * The type of function that is called with the API loaded.
 */
typedef void *(*DisfluidUser) (const DisfluidApi * api, void *data);

/**
 * disfluid_api_init:
 *
 * @func: (scope call) (not nullable): the function to call with the API loaded.
 * @data: (closure func): the second argument for @func.
 *
 * Call @func in a context where the API function can be called. The
 * API is unloaded when the function exits.
 *
 * Returns: (transfer none): the result of the callback.
 */
void *disfluid_api_init (DisfluidUser func, void *data);

/**
 * DisfluidClient:
 *
 * A client contains a client ID, redirection URI and an associated
 * key pair.
 */
struct DisfluidClient;
typedef struct DisfluidClient DisfluidClient;

/**
 * disfluid_api_make_client:
 * @api: the context loaded with @disfluid_init.
 * @client: (out) (transfer full): where to store the allocated client.
 * @client_id: the URI serving a client manifest on the web.
 * @redirect_uri: the URI where we can get back an authorization code.
 * @jwk: the JWK encoding of the key pair used by the client.
 *
 * Create a new client.
 */
void disfluid_api_make_client (const DisfluidApi * api,
			       DisfluidClient ** client,
			       const char *client_id,
			       const char *redirect_uri, const char *jwk);

/**
 * disfluid_client_free:
 * @client: the client to free.
 *
 * Delete @client.
 */
void disfluid_client_free (DisfluidClient * client);

/**
 * disfluid_client_copy:
 * @client: the client to copy.
 * @api: the API.
 * @copy: (out) (transfer full): the copy.
 */
void disfluid_client_copy (const DisfluidClient * client,
			   const DisfluidApi * api, DisfluidClient ** copy);

/**
 * disfluid_client_get_id:
 * @client: the client whose ID to lookup.
 * @api: the context API.
 * @start: how many URL prefix bytes to skip.
 * @max: how many URL bytes to copy after the skipped prefix.
 * @id: (array length=max) (element-type char): where to copy the URL bytes.
 * Returns: the total number of bytes in the URL.
 */
size_t disfluid_client_get_id (const DisfluidClient * client,
			       const DisfluidApi * api,
			       size_t start, size_t max, char *id);

/**
 * disfluid_client_get_redirect_uri:
 * @client: the client whose redirection URI to lookup.
 * @api: the context API.
 * @start: how many URL prefix bytes to skip.
 * @max: how many URL bytes to copy after the skipped prefix.
 * @redirect_uri: (array length=max) (element-type char): where to copy the URL bytes.
 * Returns: the total number of bytes in the URL.
 */
size_t disfluid_client_get_redirect_uri (const DisfluidClient * client,
					 const DisfluidApi * api,
					 size_t start, size_t max,
					 char *redirect_uri);

/**
 * disfluid_client_get_key_pair:
 * @client: the client whose key pair to dump.
 * @api: the context API.
 * @start: how many JWK prefix bytes to skip.
 * @max: how many JWK bytes to copy after the skipped prefix.
 * @jwk: (array length=max) (element-type char): where to copy the JWK bytes.
 * Returns: the total number of bytes in the JWK.
 */
size_t disfluid_client_get_key_pair (const DisfluidClient * client,
				     const DisfluidApi * api,
				     size_t start, size_t max, char *jwk);

/**
 * DisfluidAccount:
 *
 * An accounts is an ID, issuer, a key pair, and some optional tokens
 * (ID, access and refresh tokens).
 */
struct DisfluidAccount;
typedef struct DisfluidAccount DisfluidAccount;

/**
 * disfluid_api_make_account_full:
 * @api: the context loaded with @disfluid_init.
 * @account: (out) (transfer full): where to store the allocated account.
 * @subject: the URI serving the webid.
 * @issuer: the identity provider URI.
 * @key_pair: the key pair encoded as a JWK.
 * @id_token_header: (nullable): the ID token header, or NULL.
 * @id_token: (nullable): the ID token payload, or NULL.
 * @access_token: (nullable): the encoded access token, or NULL.
 * @refresh_token: (nullable): the refresh token, or NULL.
 *
 * Create a new account.
 */
void disfluid_api_make_account_full (const DisfluidApi * api,
				     DisfluidAccount ** account,
				     const char *subject,
				     const char *issuer,
				     const char *key_pair,
				     const char *id_token_header,
				     const char *id_token,
				     const char *access_token,
				     const char *refresh_token);

/**
 * disfluid_account_free:
 * @account: the account to free.
 *
 * Delete @account.
 */
void disfluid_account_free (DisfluidAccount * account);

/**
 * disfluid_account_copy:
 * @account: the account to copy.
 * @api: the API.
 * @copy: (out) (transfer full): the copy.
 */
void disfluid_account_copy (const DisfluidAccount * account,
			    const DisfluidApi * api, DisfluidAccount ** copy);

/**
 * disfluid_account_get_subject:
 * @account: the account whose subject to lookup.
 * @api: the context API.
 * @start: how many URL prefix bytes to skip.
 * @max: how many URL bytes to copy after the skipped prefix.
 * @subject: (array length=max) (element-type char): where to copy the URL bytes.
 * Returns: the total number of bytes in the URL.
 */
size_t disfluid_account_get_subject (const DisfluidAccount * account,
				     const DisfluidApi * api,
				     size_t start, size_t max, char *subject);

/**
 * disfluid_account_get_issuer:
 * @account: the account whose issuer to lookup.
 * @api: the context API.
 * @start: how many URL prefix bytes to skip.
 * @max: how many URL bytes to copy after the skipped prefix.
 * @issuer: (array length=max) (element-type char): where to copy the URL bytes.
 * Returns: the total number of bytes in the URL.
 */
size_t disfluid_account_get_issuer (const DisfluidAccount * account,
				    const DisfluidApi * api,
				    size_t start, size_t max, char *issuer);

/**
 * disfluid_account_get_key_pair:
 * @account: the account whose key pair to dump.
 * @api: the context API.
 * @start: how many JWK prefix bytes to skip.
 * @max: how many JWK bytes to copy after the skipped prefix.
 * @jwk: (array length=max) (element-type char): where to copy the JWK bytes.
 * Returns: the total number of bytes in the JWK.
 */
size_t disfluid_account_get_key_pair (const DisfluidAccount * account,
				      const DisfluidApi * api,
				      size_t start, size_t max, char *jwk);

/**
 * disfluid_account_get_id_token_header:
 * @account: the account whose ID token to lookup.
 * @api: the context API.
 * @start: how many JSON prefix bytes to skip.
 * @max: how many JSON bytes to copy after the skipped prefix.
 * @header: (array length=max) (element-type char): where to copy the JSON bytes.
 * Returns: the total number of bytes in the JSON.
 *
 * If the account does not have a valid ID token, 0 is returned.
 */
size_t disfluid_account_get_id_token_header (const DisfluidAccount * account,
					     const DisfluidApi * api,
					     size_t start, size_t max,
					     char *header);

/**
 * disfluid_account_get_id_token:
 * @account: the account whose ID token to lookup.
 * @api: the context API.
 * @start: how many JSON prefix bytes to skip.
 * @max: how many JSON bytes to copy after the skipped prefix.
 * @token: (array length=max) (element-type char): where to copy the JSON bytes.
 * Returns: the total number of bytes in the JSON.
 *
 * If the account does not have a valid ID token, 0 is returned.
 */
size_t disfluid_account_get_id_token (const DisfluidAccount * account,
				      const DisfluidApi * api,
				      size_t start, size_t max, char *token);

/**
 * disfluid_account_get_access_token:
 * @account: the account whose access token to lookup.
 * @api: the context API.
 * @start: how many JWT prefix bytes to skip.
 * @max: how many JWT bytes to copy after the skipped prefix.
 * @token: (array length=max) (element-type char): where to copy the JWT bytes.
 * Returns: the total number of bytes in the JWT.
 *
 * If the account does not have a valid access token, 0 is returned.
 */
size_t disfluid_account_get_access_token (const DisfluidAccount * account,
					  const DisfluidApi * api,
					  size_t start, size_t max,
					  char *token);

/**
 * disfluid_account_get_refresh_token:
 * @account: the account whose refresh token to lookup.
 * @api: the context API.
 * @start: how many prefix bytes to skip.
 * @max: how many bytes to copy after the skipped prefix.
 * @token: (array length=max) (element-type char): where to copy the refresh token bytes.
 * Returns: the total number of bytes in the refresh token.
 *
 * If the account does not have a valid refresh token, 0 is returned.
 */
size_t disfluid_account_get_refresh_token (const DisfluidAccount * account,
					   const DisfluidApi * api,
					   size_t start, size_t max,
					   char *token);

#endif