#ifndef AMALGAM_AST_H
#define AMALGAM_AST_H

#include "defs.h"
#include "std/defs.h"
#include "std/buffer_view.h"
#include "std/buffer.h"
#include "std/misc.h"
#include "std/scoped_allocator.h"
#include "std/hash_map.h"
#include "binop_type.h"
#include "ssa/ssa.h"

#include <setjmp.h>

/* General error */
#define AST_ERR -1
#define AST_ERR_DEF_DUP -20

typedef struct FunctionDecl FunctionDecl;
typedef struct FunctionCall FunctionCall;
typedef struct StructDecl StructDecl;
typedef struct StructField StructField;
typedef struct LhsExpr LhsExpr;
typedef struct Import Import;
typedef struct String String;
typedef struct Variable Variable;
typedef struct Number Number;
typedef struct Binop Binop;

typedef union {
    void *data;
    FunctionDecl *func_decl;
    FunctionCall *func_call;
    StructDecl *struct_decl;
    StructField *struct_field;
    LhsExpr *lhs_expr;
    Import *import;
    String *string;
    Number *number;
    Variable *variable;
    Binop *binop;
} AstValue;

typedef enum {
    AST_NONE,
    AST_FUNCTION_DECL,
    AST_FUNCTION_CALL,
    AST_STRUCT_DECL,
    AST_STRUCT_FIELD,
    AST_LHS,
    AST_IMPORT,
    AST_STRING,
    AST_NUMBER,
    AST_VARIABLE,
    AST_BINOP
} AstType;

typedef enum {
    AST_NOT_RESOLVED,
    AST_RESOLVING,
    AST_RESOLVED
} AstResolveStatus;

typedef struct {
    AstValue value;
    AstType type;
    AstResolveStatus resolve_status;
    LhsExpr *resolved_type;
} Ast;

struct Scope {
    Buffer ast_objects;
    HashMap/*(key=BufferView, value=Ast<LhsExpr>)*/ named_objects;
    Scope *parent;
};

struct FileScopeReference {
    Scope *scope;
    Buffer canonical_path;
};

struct Variable {
    BufferView name;
};

struct FunctionDecl {
    Scope body;
    SsaFuncIndex ssa_func_index;
};

struct FunctionCall {
    Variable func;
    Buffer/*Ast*/ args;
};

struct StructDecl {
    Scope body;
};

struct StructField {
    BufferView name;
    Variable type;
};

struct LhsExpr {
    bool is_pub;
    bool is_const;
    BufferView var_name;
    Variable type;
    Ast rhs_expr;
    /*
    A mutex is only available if the LhsExpr is public, because other threads (files)
    can access it. It's used to prevent usage of unresolved data and also to decide which
    thread has responsibility of resolving data.
    TODO: Find a better way to store this. This most likely will use too much memory.
    */
    amal_mutex *mutex;
};

struct Import {
    BufferView path;
    FileScopeReference *file_scope;
};

struct String {
    BufferView str;
};

struct Number {
    union {
        i64 integer;
        f64 floating;
    } value;
    bool is_integer;
};

struct Binop {
    Ast lhs;
    Ast rhs;
    BinopType type;
    /* Is the binop already ordered - no need to reorder it */
    bool grouped;
};

typedef struct {
    jmp_buf env;
    Parser *parser;
    Scope *scope;
} AstCompilerContext;

Ast ast_none();
void ast_init(Ast *self, void *value, AstType type);
BufferView ast_get_name(Ast *self);

CHECK_RESULT int funcdecl_init(FunctionDecl *self, Scope *parent, ScopedAllocator *allocator);
CHECK_RESULT int funccall_init(FunctionCall *self, BufferView name, ScopedAllocator *allocator);
CHECK_RESULT int structdecl_init(StructDecl *self, Scope *parent, ScopedAllocator *allocator);
void structfield_init(StructField *self, BufferView name, BufferView type_name);
CHECK_RESULT int lhsexpr_init(LhsExpr *self, bool is_pub, bool is_const, BufferView var_name, ScopedAllocator *allocator);
void import_init(Import *self, BufferView path);
CHECK_RESULT int string_init(String *self, BufferView str);
void number_init(Number *self, i64 value, bool is_integer);
void variable_init(Variable *self, BufferView name);
void binop_init(Binop *self);

CHECK_RESULT int scope_init(Scope *self, Scope *parent, ScopedAllocator *allocator);
CHECK_RESULT int file_scope_reference_init(FileScopeReference *self, BufferView canonical_path, ScopedAllocator *allocator);
CHECK_RESULT int scope_add_child(Scope *self, Ast *child);
/* longjump to compiler env on failure */
void scope_resolve(Scope *self, AstCompilerContext *context);

#endif