/**
 * Holds the AST model
 */
#ifndef AST_H
#define AST_H

#include "bool.h"
#include "token.h"

#include <stddef.h>

typedef struct {
    /** @brief The name of the module being imported. */
    const char* module_name;

    /** @brief Whether the import is public or not. */
    bool is_public;
} ImportDeclaration;

typedef enum {
    TYPE_EXPRESSION_BUILTIN,
    TYPE_EXPRESSION_ARRAY
} TypeExpressionTag;

/**
 * An expression that evaluates to a type.
 */
typedef struct TypeExpression TypeExpression;
struct TypeExpression{
    /** @brief defines which entry in the union is valid */
    TypeExpressionTag tag;
    union {
        /** @brief Evaluates to an array of the given type. */
        struct {
            /** @brief A pointer to the type of the elements stored in the array. */
            TypeExpression* array;
        } array;
        /** @brief Evaluates to a builtin integer type.*/
        struct {
            /**
             * @brief The number of bits in the integer.
             * Typical values are 8, 16, 32, and 64.
             */
            int bitSize;
            /** @brief `true` if the type is signed, `false` if it's unsigned. */
            bool isSigned;
        } builtin;
    };
};

/**
 * A declaration that aliases one type to another.
 */
typedef struct {
    /** @brief The name of the alias. */
    const char* name;

    /** @brief The value of the alias. */
    TypeExpression value;

    /** @brief Whether the import is public or not. */
    bool is_public;
} AliasDeclaration;

/**
 * The top-level model.
 * Every file matches an entire Module.
 */
typedef struct {
    /** @brief The name of the module. */
    const char* name;

    /** @brief The list of imports in the module. */
    ImportDeclaration* imports;

    /** @brief The number of imports in the module. */
    size_t import_count;

    /** @brief The list of aliases in the module. */
    AliasDeclaration* aliases;

    /** @brief The number of aliases in the module. */
    size_t alias_count;
} Module;

#endif