#pragma once

// Type information and methods for TypeInfos (i.e. runtime representations of types)

#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>

#include "datatypes.h"

typedef struct TypeInfo_s TypeInfo_t;

typedef void (*serialize_fn_t)(const void*, FILE*, Table_t*, const TypeInfo_t*);
typedef void (*deserialize_fn_t)(FILE*, void*, List_t*, const TypeInfo_t*);
typedef bool (*is_none_fn_t)(const void*, const TypeInfo_t*);
typedef uint64_t (*hash_fn_t)(const void*, const TypeInfo_t*);
typedef int32_t (*compare_fn_t)(const void*, const void*, const TypeInfo_t*);
typedef bool (*equal_fn_t)(const void*, const void*, const TypeInfo_t*);
typedef Text_t (*as_text_fn_t)(const void*, bool, const TypeInfo_t*);

typedef struct {
    hash_fn_t hash;
    compare_fn_t compare;
    equal_fn_t equal;
    as_text_fn_t as_text;
    is_none_fn_t is_none;
    serialize_fn_t serialize;
    deserialize_fn_t deserialize;
} metamethods_t;

typedef struct {
    const char *name;
    const TypeInfo_t *type;
} NamedType_t;

struct TypeInfo_s {
    int64_t size, align;
    metamethods_t metamethods;
    struct { // Anonymous tagged union for convenience 
        enum { OpaqueInfo, StructInfo, EnumInfo, PointerInfo, TextInfo, ListInfo, TableInfo, FunctionInfo,
            OptionalInfo, TypeInfoInfo } tag;
        union {
            struct {} OpaqueInfo;
            struct {
                const char *sigil;
                const TypeInfo_t *pointed;
            } PointerInfo;
            struct {
                const char *lang;
            } TextInfo;
            struct {
                const TypeInfo_t *item;
            } ListInfo;
            struct {
                const TypeInfo_t *key, *value;
            } TableInfo;
            struct {
                const char *type_str;
            } FunctionInfo;
            struct {
                const char *type_str;
            } TypeInfoInfo;
            struct {
                const TypeInfo_t *type;
            } OptionalInfo;
            struct {
                const char *name;
                NamedType_t *tags;
                int num_tags;
            } EnumInfo;
            struct {
                const char *name;
                NamedType_t *fields;
                int num_fields;
                bool is_secret:1, is_opaque:1;
            } StructInfo;
        };
    };
};

extern const TypeInfo_t Voidヽinfo;
extern const TypeInfo_t Abortヽinfo;
#define Void_t void

Text_t Typeヽas_text(const void *typeinfo, bool colorize, const TypeInfo_t *type);

#define Typeヽinfo(typestr) &((TypeInfo_t){.size=sizeof(TypeInfo_t), .align=__alignof__(TypeInfo_t), \
                             .tag=TypeInfoInfo, .TypeInfoInfo.type_str=typestr, \
                             .metamethods={.serialize=cannot_serialize, .deserialize=cannot_deserialize, .as_text=Typeヽas_text}})

#define DEFINE_OPTIONAL_TYPE(t, unpadded_size, name) \
    typedef struct { \
        union { \
            t value; \
            struct { \
                char _padding[unpadded_size]; \
                Bool_t is_none; \
            }; \
        }; \
    } name
// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1,\:0