#ifndef NCTREF_VARTABLE_H
#define NCTREF_VARTABLE_H

#include"types.h"
#include<stdbool.h>

struct Token;
union AST;

typedef enum {
	SCOPEITEM_SYMBOL, SCOPEITEM_VAR, SCOPEITEM_TYPE, SCOPEITEM_CEXPR
} ScopeItemKind;

union AST;
typedef struct UseDef {
	union AST *def; // assign stmt
	union AST *use; // corresponding AST_EXPR_VAR
	union AST *stmt; // whole using stmt
	struct UseDef *next;
} UseDef;

typedef struct ReachingDefs {
	size_t defCount;
	union AST **defs;
} ReachingDefs;

struct Scope;
typedef struct ScopeItem {
	Type *type;
	
	struct Scope *owner;
	
	ScopeItemKind kind;
	union {
		struct {
			char isLocal;
			char isExternal;
			const char *name;
			
			struct {
				struct Scope *scope;
				struct Token *rangeTokens;
				size_t startTokI;
				size_t endTokI;
			} genfunc;
		} symbol;
		struct {
			// For debugging
			
			const char *name;
			
			// Register allocation
			
			// vars in loops have higher priority
			// a more advanced approach would be to use weights for different colors (e.g. multipliers "should" be in eax)
			uint8_t priority;
			int16_t color, degree;
			bool precolored, preclassed;
			int registerClass;
			
			// Used by ast_usedef_pass
			//ReachingDefs *reachingDefs;
			union AST *declaration;
			
			UseDef *usedefFirst;
			UseDef *usedefLast;
			
			union AST *liveRangeStart;
			union AST *liveRangeEnd;
		} var;
		struct {
			Type *ptr;
		} type;
		struct {
			// cexpr is used for expression parametization as opposed to type parametrization
			// I don't like the idea of having a special ScopeItem kind for these, but all other places were worse
			const char *paramName;
			size_t paramIdx;
			
			// If the cexpr has been parametrized (as opposed to just being a symbol), this field will be non-NULL
			union AST *concrete;
		} cexpr;
	} data;
} ScopeItem;

typedef struct Scope {
	struct Scope *parent;
	
	size_t count;
	const char **names;
	ScopeItem **data;
} Scope;

Scope *scope_new(Scope*);
ScopeItem *scope_get(Scope*, const char*);
ScopeItem *scope_find(Scope*, const char*);
ScopeItem *scope_set(Scope*, const char*, ScopeItem*);

ScopeItem *scope_find_int(Scope*, intmax_t, const char*);

Scope *scope_merge(Scope *child);

void vte_precolor(ScopeItem *vte, int resclass, int color);

#endif