/*
 * Copyright 2024 Vsevolod Stakhov
 *
 * 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.
 */
#ifndef CFG_RCL_H_
#define CFG_RCL_H_

#include "config.h"
#include "cfg_file.h"
#include "ucl.h"
#include "mem_pool.h"

#define CFG_RCL_ERROR cfg_rcl_error_quark()
static inline GQuark
cfg_rcl_error_quark(void)
{
	return g_quark_from_static_string("cfg-rcl-error-quark");
}

#ifdef __cplusplus
extern "C" {
#endif

struct rspamd_rcl_section;
struct rspamd_rcl_sections_map;
struct rspamd_config;
struct rspamd_rcl_default_handler_data;

enum rspamd_rcl_flag {
	RSPAMD_CL_FLAG_TIME_FLOAT = 0x1 << 0,
	RSPAMD_CL_FLAG_TIME_TIMEVAL = 0x1 << 1,
	RSPAMD_CL_FLAG_TIME_TIMESPEC = 0x1 << 2,
	RSPAMD_CL_FLAG_TIME_INTEGER = 0x1 << 3,
	RSPAMD_CL_FLAG_TIME_UINT_32 = 0x1 << 4,
	RSPAMD_CL_FLAG_INT_16 = 0x1 << 5,
	RSPAMD_CL_FLAG_INT_32 = 0x1 << 6,
	RSPAMD_CL_FLAG_INT_64 = 0x1 << 7,
	RSPAMD_CL_FLAG_UINT = 0x1 << 8,
	RSPAMD_CL_FLAG_INT_SIZE = 0x1 << 9,
	RSPAMD_CL_FLAG_STRING_PATH = 0x1 << 10,
	RSPAMD_CL_FLAG_BOOLEAN_INVERSE = 0x1 << 11,
	RSPAMD_CL_FLAG_STRING_LIST_HASH = 0x1 << 12,
	RSPAMD_CL_FLAG_MULTIPLE = 0x1 << 13,
	RSPAMD_CL_FLAG_SIGNKEY = 0x1 << 14,
};

struct rspamd_rcl_struct_parser {
	struct rspamd_config *cfg;
	gpointer user_struct;
	goffset offset;
	int flags; /* enum rspamd_rcl_flag */
};


/**
 * Common handler type
 * @param cfg configuration
 * @param obj object to parse
 * @param ud user data (depends on section)
 * @param err error object
 * @return TRUE if a section has been parsed
 */
typedef gboolean (*rspamd_rcl_handler_t)(rspamd_mempool_t *pool,
										 const ucl_object_t *obj,
										 const char *key,
										 gpointer ud,
										 struct rspamd_rcl_section *section,
										 GError **err);

typedef gboolean (*rspamd_rcl_default_handler_t)(rspamd_mempool_t *pool,
												 const ucl_object_t *obj,
												 gpointer ud,
												 struct rspamd_rcl_section *section,
												 GError **err);

/**
 * A handler type that is called at the end of section parsing
 * @param cfg configuration
 * @param ud user data
 */
typedef void (*rspamd_rcl_section_fin_t)(rspamd_mempool_t *pool, gpointer ud);

/**
 * Add a default handler for a section
 * @param section section pointer
 * @param name name of param
 * @param handler handler of param
 * @param offset offset in a structure
 * @param flags flags for the parser
 * @return newly created structure
 */
struct rspamd_rcl_default_handler_data *rspamd_rcl_add_default_handler(
	struct rspamd_rcl_section *section,
	const char *name,
	rspamd_rcl_default_handler_t handler,
	goffset offset,
	int flags,
	const char *doc_string);

/**
 * Add new section to the configuration
 * @param top top section
 * @param name the name of the section
 * @param key_attr name of the attribute that should be used as key attribute
 * @param handler handler function for all attributes
 * @param type type of object handled by a handler
 * @param required whether at least one of these sections is required
 * @param strict_type turn on strict check for types for this section
 * @return newly created structure
 */
struct rspamd_rcl_section *rspamd_rcl_add_section(
	struct rspamd_rcl_sections_map **top,
	struct rspamd_rcl_section *parent_section,
	const char *name,
	const char *key_attr,
	rspamd_rcl_handler_t handler,
	enum ucl_type type,
	gboolean required,
	gboolean strict_type);

struct rspamd_rcl_section *rspamd_rcl_add_section_doc(
	struct rspamd_rcl_sections_map **top,
	struct rspamd_rcl_section *parent_section,
	const char *name, const char *key_attr,
	rspamd_rcl_handler_t handler,
	enum ucl_type type, gboolean required,
	gboolean strict_type,
	ucl_object_t *doc_target,
	const char *doc_string);

/**
 * Init common sections known to rspamd
 * @return top section
 */
struct rspamd_rcl_sections_map *rspamd_rcl_config_init(struct rspamd_config *cfg,
													   GHashTable *skip_sections);

/**
 * Parse configuration
 * @param top top section
 * @param cfg rspamd configuration
 * @param ptr pointer to the target
 * @param pool pool object
 * @param obj ucl object to parse
 * @param err error pointer
 * @return
 */
gboolean rspamd_rcl_parse(struct rspamd_rcl_sections_map *top,
						  struct rspamd_config *cfg,
						  gpointer ptr, rspamd_mempool_t *pool,
						  const ucl_object_t *obj, GError **err);

/**
 * Here is a section of common handlers that accepts rcl_struct_parser
 * which itself contains a struct pointer and the offset of a member in a
 * specific structure
 */

/**
 * Parse a string field of a structure
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a string value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_string(rspamd_mempool_t *pool,
										const ucl_object_t *obj,
										gpointer ud,
										struct rspamd_rcl_section *section,
										GError **err);

/**
 * Parse an integer field of a structure
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_integer(rspamd_mempool_t *pool,
										 const ucl_object_t *obj,
										 gpointer ud,
										 struct rspamd_rcl_section *section,
										 GError **err);


/**
 * Parse a float field of a structure
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_double(rspamd_mempool_t *pool,
										const ucl_object_t *obj,
										gpointer ud,
										struct rspamd_rcl_section *section,
										GError **err);

/**
 * Parse a time field of a structure
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure (flags mean the exact structure used)
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_time(rspamd_mempool_t *pool,
									  const ucl_object_t *obj,
									  gpointer ud,
									  struct rspamd_rcl_section *section,
									  GError **err);

/**
 * Parse a string list field of a structure presented by a GList* object
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure (flags mean the exact structure used)
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_string_list(rspamd_mempool_t *pool,
											 const ucl_object_t *obj,
											 gpointer ud,
											 struct rspamd_rcl_section *section,
											 GError **err);

/**
 * Parse a boolean field of a structure
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure (flags mean the exact structure used)
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_boolean(rspamd_mempool_t *pool,
										 const ucl_object_t *obj,
										 gpointer ud,
										 struct rspamd_rcl_section *section,
										 GError **err);

/**
 * Parse a keypair field of a structure
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure (flags mean the exact structure used)
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_keypair(rspamd_mempool_t *pool,
										 const ucl_object_t *obj,
										 gpointer ud,
										 struct rspamd_rcl_section *section,
										 GError **err);

/**
 * Parse a pubkey field of a structure
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure (flags mean the exact structure used)
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_pubkey(rspamd_mempool_t *pool,
										const ucl_object_t *obj,
										gpointer ud,
										struct rspamd_rcl_section *section,
										GError **err);

/**
 * Parse a inet addr field of a structure
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure (flags mean the exact structure used)
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_addr(rspamd_mempool_t *pool,
									  const ucl_object_t *obj,
									  gpointer ud,
									  struct rspamd_rcl_section *section,
									  GError **err);

/**
 * Parse a gmime inet address field of a structure
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure (flags mean the exact structure used)
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_mime_addr(rspamd_mempool_t *pool,
										   const ucl_object_t *obj,
										   gpointer ud,
										   struct rspamd_rcl_section *section,
										   GError **err);

/**
 * Parse a raw ucl object
 * @param cfg config pointer
 * @param obj object to parse
 * @param ud struct_parser structure (flags mean the exact structure used)
 * @param section the current section
 * @param err error pointer
 * @return TRUE if a value has been successfully parsed
 */
gboolean rspamd_rcl_parse_struct_ucl(rspamd_mempool_t *pool,
									 const ucl_object_t *obj,
									 gpointer ud,
									 struct rspamd_rcl_section *section,
									 GError **err);


/**
 * Utility functions
 */

/**
 * Register new parser for a worker type of an option with the specified name
 * @param cfg config structure
 * @param type type of worker (GQuark)
 * @param name name of option
 * @param handler handler of option
 * @param target opaque target structure, note it **MUST** be worker ctx due to some reasons I don't really remember
 * @param offset offset inside a structure
 */
void rspamd_rcl_register_worker_option(struct rspamd_config *cfg,
									   GQuark type,
									   const char *name,
									   rspamd_rcl_default_handler_t handler,
									   gpointer target,
									   glong offset,
									   int flags,
									   const char *doc_string);

/**
 * Adds new documentation object to the configuration
 * @param doc_target target object where to insert documentation (top object is used if this is NULL)
 * @param doc_object documentation object to insert
 */
ucl_object_t *rspamd_rcl_add_doc_obj(ucl_object_t *doc_target,
									 const char *doc_string,
									 const char *doc_name,
									 ucl_type_t type,
									 rspamd_rcl_default_handler_t handler,
									 int flags,
									 const char *default_value,
									 gboolean required);

/**
 * Adds new documentation option specified by path `doc_path` that should be
 * split by dots
 */
ucl_object_t *rspamd_rcl_add_doc_by_path(struct rspamd_config *cfg,
										 const char *doc_path,
										 const char *doc_string,
										 const char *doc_name,
										 ucl_type_t type,
										 rspamd_rcl_default_handler_t handler,
										 int flags,
										 const char *default_value,
										 gboolean required);


/**
 * Parses example and adds documentation according to the example:
 *
 * ```
 * section {
 *   param1 = value; # explanation
 *   param2 = value; # explanation
 * }
 * ```
 *
 * will produce the following documentation strings:
 * section ->
 *   section.param1 : explanation
 *   section.param2 : explanation
 *
 * @param cfg
 * @param root_path
 * @param example_data
 * @param example_len
 * @return
 */
ucl_object_t *rspamd_rcl_add_doc_by_example(struct rspamd_config *cfg,
											const char *root_path,
											const char *doc_string,
											const char *doc_name,
											const char *example_data, gsize example_len);

/**
 * Add lua modules path
 * @param cfg
 * @param path
 * @param err
 * @return
 */
gboolean rspamd_rcl_add_lua_plugins_path(struct rspamd_rcl_sections_map *sections,
										 struct rspamd_config *cfg,
										 const char *path,
										 gboolean main_path,
										 GError **err);


/**
 * Calls for an external lua function to apply potential config transformations
 * if needed. This function can change the cfg->rcl_obj.
 *
 * Example of transformation function:
 *
 * function(obj)
 *   if obj.something == 'foo' then
 *     obj.something = "bla"
 *     return true, obj
 *   end
 *
 *   return false, nil
 * end
 *
 * If function returns 'false' then rcl_obj is not touched. Otherwise,
 * it is changed, then rcl_obj is imported from lua. Old config is dereferenced.
 * @param cfg
 */
void rspamd_rcl_maybe_apply_lua_transform(struct rspamd_config *cfg);
void rspamd_rcl_sections_free(struct rspamd_rcl_sections_map *sections);

void rspamd_config_calculate_cksum(struct rspamd_config *cfg);

/*
 * Read configuration file
 */
gboolean rspamd_config_parse_ucl(struct rspamd_config *cfg,
								 const char *filename,
								 GHashTable *vars,
								 ucl_include_trace_func_t inc_trace,
								 void *trace_data,
								 gboolean skip_jinja,
								 GError **err);
gboolean rspamd_config_read(struct rspamd_config *cfg,
							const char *filename,
							rspamd_rcl_section_fin_t logger_fin,
							gpointer logger_ud,
							GHashTable *vars,
							gboolean skip_jinja,
							char **lua_env);

#ifdef __cplusplus
}
#endif

#endif /* CFG_RCL_H_ */