#ifndef AST_EXPRESSION_H
#define AST_EXPRESSION_H

#include "../bool.h"

typedef enum {
    EXPRESSION_INTEGER,
    EXPRESSION_STRING,
    EXPRESSION_BOOLEAN
} ExpressionTag;

typedef struct {
    ExpressionTag tag;
    union {
        int integer;
        const char* string;
        bool boolean;
    };
} Expression;

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;
    };
};

#endif