#ifndef AST_H
#define AST_H

#include "collection.h"
#include <stdio.h>

typedef struct {
    int line;
    int col;
} Loc;

typedef struct AstStmt AstStmt;
typedef struct AstDecl AstDecl;
typedef struct AstDeclar AstDeclar;
typedef struct AstExpr AstExpr;

typedef struct AstStmtBlock AstStmtBlock;

struct AstStmtBlock {
    ARRAY_FIELD(AstStmt*, stmts);
    Loc loc;
};

typedef struct AstDeclBlock AstDeclBlock;

struct AstDeclBlock {
    ARRAY_FIELD(AstDecl*, decls);
    Loc loc;
};

typedef enum {
    AstStmt_Decl,
    AstStmt_Expr,
} AstStmtTy;

struct AstStmt {
    AstStmtTy ty;
    Loc loc;
    union {
        AstDecl* decl;
        AstExpr* expr;
    };
};

typedef enum : unsigned int {
    AstSpec_Int = 1 << 0,
    AstSpec_Char = 1 << 1,
    AstSpec_Void = 1 << 2,
    AstSpec_DefTy = 1 << 6,
    AstSpec_Unsigned = 1 << 7,
    AstSpec_Static = 1 << 8,
    AstSpec_Const = 1 << 9,
    AstSpec_Inline = 1 << 10,
    AstSpec_Typedef = 1 << 11,
    AstSpec_Enum = 1 << 12,
    AstSpec_Struct = 1 << 13,
    AstSpec_Union = 1 << 14,
} AstSpec;

struct AstDecl {
    AstSpec spec;
    char* type_ident;
    ARRAY_FIELD(AstDeclar*, declars);
    AstStmtBlock* function_body;
    Loc loc;
};

typedef enum {
    AstDeclar_Ident,
    AstDeclar_Pointer,
    AstDeclar_Array,
    AstDeclar_Function,
} AstDeclarTy;

struct AstDeclar {
    AstDeclarTy ty;
    Loc loc;
    AstExpr* init_expr;
    union {
        char* ident;
        struct {
            AstDeclar* declar;
            AstSpec spec;
        } pointer;
        struct {
            AstDeclar* declar;
            AstExpr* expr;
        } array;
        struct {
            AstDeclar* declar;
            ARRAY_FIELD(AstDecl*, params);
        } function;
    };
};

typedef enum {
    AstExpr_Ident,
    AstExpr_Str,
    AstExpr_Call,
} AstExprTy;

struct AstExpr {
    AstExprTy ty;
    Loc loc;
    union {
        char* ident;
        char* str_val;
        struct {
            AstExpr* expr;
            ARRAY_FIELD(AstExpr*, args);
        } call;
    };
};

void ast_stmt_block_print(FILE* f, const AstStmtBlock* node, int depth);
void ast_stmt_print(FILE* f, const AstStmt* node, int depth);
void ast_decl_print(FILE* f, const AstDecl* node, int depth);
void ast_declar_print(FILE* f, const AstDeclar* node, int depth);
void ast_expr_print(FILE* f, const AstExpr* node, int depth);

typedef struct AstVisitor AstVisitor;

typedef enum {
    AstVisitor_Continue,
    AstVisitor_Break,
} AstVisitorResult;

struct AstVisitor {
    AstVisitorResult (*visit_stmt_block)(AstVisitor* v, AstStmtBlock* node);
    AstVisitorResult (*visit_stmt)(AstVisitor* v, AstStmt* node);
    AstVisitorResult (*visit_decl)(AstVisitor* v, AstDecl* node);
    AstVisitorResult (*visit_declar)(AstVisitor* v, AstDeclar* node);
    AstVisitorResult (*visit_expr)(AstVisitor* v, AstExpr* node);
    void* op;
};

void ast_stmt_block_visit(AstVisitor* v, AstStmtBlock* node);
void ast_stmt_block_visit_body(AstVisitor* v, AstStmtBlock* node);
void ast_stmt_visit(AstVisitor* v, AstStmt* node);
void ast_stmt_visit_body(AstVisitor* v, AstStmt* node);
void ast_decl_visit(AstVisitor* v, AstDecl* node);
void ast_decl_visit_body(AstVisitor* v, AstDecl* node);
void ast_declar_visit(AstVisitor* v, AstDeclar* node);
void ast_declar_visit_body(AstVisitor* v, AstDeclar* node);
void ast_expr_visit(AstVisitor* v, AstExpr* node);
void ast_expr_visit_body(AstVisitor* v, AstExpr* node);

#endif