#ifndef BLUELIB_COMMAND_H_
#define BLUELIB_COMMAND_H_

#include <blue/core/btree.h>
#include <blue/core/init.h>
#include <blue/core/iterator.h>
#include <blue/core/queue.h>
#include <blue/object/array.h>
#include <stdbool.h>

#define b_arglist_foreach(it, q)                                               \
	for (int z__b_unique_name() = b_arglist_iterator_begin(                \
		     q, B_COMMAND_INVALID_ID, B_COMMAND_INVALID_ID, (it));     \
	     b_arglist_iterator_is_valid(it); b_arglist_iterator_next(it))

#define b_arglist_foreach_filtered(it, q, opt_id, arg_id)                      \
	for (int z__b_unique_name()                                            \
	     = b_arglist_iterator_begin(q, opt_id, arg_id, (it));              \
	     b_arglist_iterator_is_valid(it); b_arglist_iterator_next(it))

#define B_COMMAND(id, parent_id)                                               \
	static b_command *command_##id = NULL;                                 \
	static void __init_##id(                                               \
		b_command *, b_command_option *, b_command_arg *,              \
		b_command_usage *);                                            \
	B_INIT(init_##id)                                                      \
	{                                                                      \
		command_##id = b_command_create(id);                           \
		if ((parent_id) != B_COMMAND_INVALID_ID) {                     \
			b_command_set_parent(command_##id, parent_id);         \
		}                                                              \
		__init_##id(command_##id, NULL, NULL, NULL);                   \
		b_command_register(command_##id);                              \
	}                                                                      \
	static void __init_##id(                                               \
		b_command *this_cmd, b_command_option *this_opt,               \
		b_command_arg *this_arg, b_command_usage *this_usage)

#define B_COMMAND_NAME(name)       b_command_set_name(this_cmd, (name))
#define B_COMMAND_LONG_NAME(name)  b_command_set_long_name(this_cmd, (name))
#define B_COMMAND_SHORT_NAME(name) b_command_set_short_name(this_cmd, (name))
#define B_COMMAND_DESC(desc)       b_command_set_description(this_cmd, (desc))
#define B_COMMAND_FLAGS(flags)     b_command_set_flags(this_cmd, (flags))
#define B_COMMAND_FUNCTION(fn)     b_command_set_callback(this_cmd, (fn))

#define B_COMMAND_OPTION(id)                                                   \
	b_command_option *opt_##id = b_command_add_option(this_cmd, (id));     \
	this_opt = opt_##id;                                                   \
	if (this_opt)

#define B_COMMAND_HELP_OPTION()                                                  \
	do {                                                                     \
		b_command_option *opt                                            \
			= b_command_add_option(this_cmd, B_COMMAND_OPTION_HELP); \
		b_command_option_set_description(opt, "Show this help message"); \
		b_command_option_set_short_name(opt, 'h');                       \
		b_command_option_set_long_name(opt, "help");                     \
	} while (0)

#define B_OPTION_LONG_NAME(name)                                               \
	b_command_option_set_long_name(this_opt, (name))

#define B_OPTION_SHORT_NAME(name)                                              \
	b_command_option_set_short_name(this_opt, (name))

#define B_OPTION_DESC(desc) b_command_option_set_description(this_opt, (desc))

#define B_OPTION_ARG(id)                                                       \
	b_command_arg *arg_##id = b_command_option_add_arg(this_opt, (id));    \
	this_arg = arg_##id;                                                   \
	if (this_arg)

#define B_COMMAND_ARG(id)                                                      \
	b_command_arg *arg_##id = b_command_add_arg(this_cmd, (id));           \
	this_arg = arg_##id;                                                   \
	if (this_arg)

#define B_ARG_NAME(name) b_command_arg_set_name(this_arg, (name))

#define B_ARG_DESC(desc) b_command_arg_set_description(this_arg, (desc))

#define B_ARG_NR_VALUES(nr_values)                                             \
	b_command_arg_set_nr_values(this_arg, (nr_values))

#define B_ARG_ALLOWED_VALUES(...)                                              \
	static const char *allowed_values[] = {                                \
		__VA_ARGS__,                                                   \
		NULL,                                                          \
	};                                                                     \
	b_command_arg_set_allowed_values(this_arg, allowed_values)

#define B_COMMAND_USAGE()                                                      \
	b_command_usage *usage_##__LINE__ = b_command_add_usage(this_cmd);     \
	this_usage = usage_##__LINE__;                                         \
	if (this_usage)

#define B_COMMAND_USAGE_OPT(opt_id)                                            \
	b_command_usage_add_option(this_usage, opt_##opt_id)

#define B_COMMAND_USAGE_ARG(opt_id)                                            \
	b_command_usage_add_arg(this_usage, arg_##opt_id)

#define B_COMMAND_OPTION_HELP ((unsigned int)0xF0000001)
#define B_COMMAND_INVALID_ID  ((unsigned int)0xFFFFFFFF)

typedef enum b_command_arg_value_count {
	B_ARG_0_OR_1_VALUES = -1,
	B_ARG_0_OR_MORE_VALUES = -2,
	B_ARG_1_OR_MORE_VALUES = -3,
} b_command_arg_value_count;

typedef enum b_command_arg_type {
	B_COMMAND_ARG_NONE = 0,
	B_COMMAND_ARG_STRING,
	B_COMMAND_ARG_SIGNED_INT,
	B_COMMAND_ARG_UNSIGNED_INT,

	B_COMMAND_ARG_INT = B_COMMAND_ARG_SIGNED_INT,
} b_command_arg_type;

typedef enum b_command_flags {
	B_COMMAND_SHOW_HELP_BY_DEFAULT = 0x01u,
} b_command_flags;

typedef enum b_command_usage_flags {
	B_COMMAND_USAGE_SHOW_OPTIONS = 0x01u,
} b_command_usage_flags;

typedef struct b_arglist_value {
	unsigned int val_id;
	b_command_arg_type val_type;
	struct b_btree_node val_node;

	union {
		char *val_str;
		long long val_int;
		unsigned long long val_uint;
	};
} b_arglist_value;

typedef struct b_arglist_iterator {
	b_iterator _base;
	size_t i;

	unsigned int opt_id;
	struct b_arglist_value *value;

	b_btree_iterator _opt_it, _arg_it;
	unsigned int _opt_filter, _arg_filter;
} b_arglist_iterator;

typedef struct b_command b_command;
typedef struct b_command_option b_command_option;
typedef struct b_command_arg b_command_arg;
typedef struct b_command_usage b_command_usage;
typedef struct b_arglist b_arglist;

typedef int (*b_command_callback)(
	const b_command *, const b_arglist *, const b_array *);

extern b_command *b_command_create(unsigned int id);
extern void b_command_destroy(b_command *cmd);
extern b_status b_command_register(b_command *cmd);
extern int b_command_dispatch(unsigned int cmd_id, int argc, const char **argv);

extern b_status b_command_set_name(b_command *cmd, const char *name);
extern b_status b_command_set_long_name(b_command *cmd, const char *name);
extern b_status b_command_set_short_name(b_command *cmd, char name);
extern b_status b_command_set_flags(b_command *cmd, b_command_flags flags);
extern b_status b_command_set_description(b_command *cmd, const char *description);
extern b_status b_command_set_callback(b_command *cmd, b_command_callback callback);
extern b_status b_command_set_parent(b_command *cmd, unsigned int parent_id);
extern b_command_option *b_command_add_option(b_command *cmd, int id);
extern b_command_arg *b_command_add_arg(b_command *cmd, int id);
extern b_command_usage *b_command_add_usage(b_command *cmd);

extern b_status b_command_option_set_long_name(
	b_command_option *opt, const char *name);
extern b_status b_command_option_set_short_name(b_command_option *opt, char name);
extern b_status b_command_option_set_description(
	b_command_option *opt, const char *description);
extern b_command_arg *b_command_option_add_arg(b_command_option *opt, int id);

extern b_status b_command_arg_set_name(b_command_arg *arg, const char *name);
extern b_status b_command_arg_set_description(
	b_command_arg *arg, const char *description);
extern b_status b_command_arg_set_nr_values(
	b_command_arg *arg, b_command_arg_value_count nr_values);
extern b_status b_command_arg_set_allowed_values(
	b_command_arg *arg, const char **allowed_values);

extern b_status b_command_usage_add_option(
	b_command_usage *usage, b_command_option *opt);
extern b_status b_command_usage_add_arg(b_command_usage *usage, b_command_arg *opt);

extern b_status b_arglist_get_string(
	const b_arglist *args, unsigned int opt_id, unsigned int arg_id,
	unsigned int index, const char **out);
extern b_status b_arglist_get_int(
	const b_arglist *args, unsigned int opt_id, unsigned int arg_id,
	unsigned int index, long long *out);
extern b_status b_arglist_get_uint(
	const b_arglist *args, unsigned int opt_id, unsigned int arg_id,
	unsigned int index, unsigned long long *out);
extern size_t b_arglist_get_count(
	const b_arglist *args, unsigned int opt_id, unsigned int arg_id);

extern int b_arglist_iterator_begin(
	const b_arglist *args, unsigned int opt_filter, unsigned int arg_filter,
	b_arglist_iterator *it);
extern bool b_arglist_iterator_next(b_arglist_iterator *it);
extern bool b_arglist_iterator_is_valid(const b_arglist_iterator *it);

#endif