#ifndef OBERON_INTERNALS_H
#define OBERON_INTERNALS_H

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

typedef struct gen_module_t gen_module_t;
typedef struct gen_proc_t gen_proc_t;
typedef struct gen_type_t gen_type_t;
typedef struct gen_var_t gen_var_t;
typedef struct gen_label_t gen_label_t;
typedef struct gen_context_t gen_context_t;

typedef struct oberon_type_t oberon_type_t;
typedef struct oberon_object_t oberon_object_t;
typedef struct oberon_module_t oberon_module_t;
typedef struct oberon_context_t oberon_context_t;
typedef struct oberon_scope_t oberon_scope_t;

typedef struct oberon_location_t oberon_location_t;
typedef struct oberon_scanner_t oberon_scanner_t;
typedef struct oberon_item_t oberon_item_t;
typedef struct oberon_oper_t oberon_oper_t;
typedef union oberon_expr_t oberon_expr_t;

struct oberon_scope_t
{
	oberon_context_t * ctx;
	oberon_object_t * list;
	oberon_scope_t * up;

	int local;
	oberon_object_t * parent;
	oberon_type_t * parent_type;

	gen_label_t * exit_label;
};

enum oberon_type_kind
{
	OBERON_TYPE_NOTYPE,
	OBERON_TYPE_INTEGER,
	OBERON_TYPE_BOOLEAN,
	OBERON_TYPE_PROCEDURE,
	OBERON_TYPE_ARRAY,
	OBERON_TYPE_RECORD,
	OBERON_TYPE_POINTER,
	OBERON_TYPE_REAL,
	OBERON_TYPE_CHAR,
	OBERON_TYPE_STRING,
	OBERON_TYPE_SET,
	OBERON_TYPE_NIL,
	OBERON_TYPE_SYSTEM_BYTE,
	OBERON_TYPE_SYSTEM_PTR
};

typedef oberon_expr_t * (*GenerateFuncCallback)(oberon_context_t *, int, oberon_expr_t *);
typedef void (*GenerateProcCallback)(oberon_context_t *, int, oberon_expr_t *);

struct oberon_type_t
{
	enum oberon_type_kind class;
	int size;
	oberon_type_t * shorter;
	oberon_type_t * longer;

	int num_decl;
	oberon_type_t * base;
	oberon_object_t * decl;
	oberon_scope_t * scope;

	bool sysproc;
	GenerateFuncCallback genfunc;
	GenerateProcCallback genproc;

	oberon_module_t * module;

	int recursive;
	int initialized;
	gen_type_t * gen_type;
};

enum oberon_object_kind
{
	OBERON_CLASS_VAR,
	OBERON_CLASS_TYPE,
	OBERON_CLASS_PROC,
	OBERON_CLASS_PARAM,
	OBERON_CLASS_VAR_PARAM,
	OBERON_CLASS_CONST,
	OBERON_CLASS_FIELD,
	OBERON_CLASS_MODULE
};

struct oberon_object_t
{
	char * name;
	enum oberon_object_kind class;
	int export;
	int read_only;

	int local;
	int linked;
	int initialized;

	oberon_object_t * parent;
	oberon_type_t * parent_type;

	oberon_scope_t * scope; // for proc
	int has_return; // for proc

	oberon_type_t * type;
	oberon_item_t * value;
	oberon_object_t * next;

	oberon_module_t * module;

	gen_var_t * gen_var;
	gen_proc_t * gen_proc;
};

struct oberon_module_t
{
	char * name;
	bool ready;
	bool intrinsic;

	oberon_scope_t * decl;

	oberon_module_t * next;

	gen_module_t * gen_mod;
};

struct oberon_location_t
{
	const char * source;
	int line;
	int col;
};

struct oberon_scanner_t
{
	char * source;
	char * code;
};

typedef oberon_scanner_t * (*ModuleImportCallback)(const char * name);

struct oberon_context_t
{
	/*** SCANER DATA ***/
	const char * code;
	int code_index;
	oberon_location_t loc;
	oberon_location_t xloc;

	char c;
	int token;
	char * string;
	int64_t integer;
	double real;
	bool longmode;
	/*** END SCANER DATA ***/

	/*** PARSER DATA ***/
	oberon_scope_t * decl;
	oberon_module_t * mod;
	/*** END PARSER DATA ***/

	oberon_scope_t * world_scope;
	oberon_type_t * notype_type;
	oberon_type_t * nil_type;
	oberon_type_t * bool_type;
	oberon_type_t * byte_type;
	oberon_type_t * shortint_type;
	oberon_type_t * int_type;
	oberon_type_t * longint_type;
	oberon_type_t * real_type;
	oberon_type_t * longreal_type;
	oberon_type_t * char_type;
	oberon_type_t * string_type;
	oberon_type_t * set_type;

	oberon_module_t * system_module;
	oberon_type_t * system_byte_type;
	oberon_type_t * system_ptr_type;

	oberon_module_t * module_list;
	ModuleImportCallback import_module;
	gen_context_t * gen_context;
};

enum oberon_mode_kind
{
	MODE_VAR,
	MODE_INTEGER,
	MODE_BOOLEAN,
	MODE_CALL,
	MODE_INDEX,
	MODE_FIELD,
	MODE_DEREF,
	MODE_NIL,
	MODE_NEW,
	MODE_REAL,
	MODE_CHAR,
	MODE_STRING,
	MODE_TYPE,
	MODE_SET,
	MODE_LEN,
	MODE_SYSBYTE,
	MODE_AS
};

enum oberon_operator_kind
{
	OP_UNARY_MINUS,
	OP_LOGIC_NOT,
	OP_ABS,
	OP_CAP,
	OP_ENTIER,

	OP_ADD,
	OP_SUB,
	OP_MUL,
	OP_DIV,
	OP_MOD,
	OP_LOGIC_AND,
	OP_LOGIC_OR,

	OP_EQ,
	OP_NEQ,
	OP_LSS,
	OP_LEQ,
	OP_GRT,
	OP_GEQ,

	OP_CAST,
	OP_HARDCAST,
	OP_IS,

	OP_RANGE,
	OP_UNION,
	OP_INTERSECTION,
	OP_DIFFERENCE,
	OP_SYM_DIFFERENCE,
	OP_COMPLEMENTATION,
	OP_IN,

	OP_ASH,
	OP_LSH,
	OP_ROT
};

struct oberon_item_t
{
	bool is_item; // == 1
	oberon_type_t * result;
	oberon_expr_t * next;
	bool read_only;

	enum oberon_mode_kind mode;
	long integer;
	double real;
	char * string;
	oberon_object_t * var;

	oberon_item_t * parent;

	int num_args;
	oberon_expr_t * args;
};

struct oberon_oper_t
{
	bool is_item; // == 0
	oberon_type_t * result;
	oberon_expr_t * next;
	bool read_only;

	enum oberon_operator_kind op;
	oberon_expr_t * left;
	oberon_expr_t * right;
};

union oberon_expr_t
{
	struct {
		bool is_item;
		oberon_type_t * result;
		oberon_expr_t * next;
		bool read_only;
	};

	oberon_item_t item;
	oberon_oper_t oper;
};

extern oberon_context_t *
oberon_create_context(ModuleImportCallback import_module);

extern void
oberon_destroy_context(oberon_context_t * ctx);

extern oberon_module_t *
oberon_compile_module(oberon_context_t * ctx, oberon_scanner_t * s);

#endif // OBERON_INTERNALS_H