struct Ast_Scope;
struct Ast_Decl;
struct Ast_File_Namespace;
struct Ast_File;
struct Ast_Module;
struct Ast_Type;
struct Ast;
struct Ast_Expr;


enum Token_Kind{
  TK_End,

/*#
import meta
for i in meta.token_kinds:
  print("  TK_" + i[0] + ",")
*/
  TK_Mul,
  TK_Div,
  TK_Mod,
  TK_LeftShift,
  TK_RightShift,
  TK_FirstMul = TK_Mul,
  TK_LastMul = TK_RightShift,
  TK_Add,
  TK_Sub,
  TK_FirstAdd = TK_Add,
  TK_LastAdd = TK_Sub,
  TK_Equals,
  TK_LesserThenOrEqual,
  TK_GreaterThenOrEqual,
  TK_LesserThen,
  TK_GreaterThen,
  TK_NotEquals,
  TK_FirstCompare = TK_Equals,
  TK_LastCompare = TK_NotEquals,
  TK_BitAnd,
  TK_BitOr,
  TK_BitXor,
  TK_And,
  TK_Or,
  TK_FirstLogical = TK_BitAnd,
  TK_LastLogical = TK_Or,
  TK_Neg,
  TK_Not,
  TK_Decrement,
  TK_Increment,
  TK_PostDecrement,
  TK_PostIncrement,
  TK_Assign,
  TK_ColonAssign,
  TK_DivAssign,
  TK_MulAssign,
  TK_ModAssign,
  TK_SubAssign,
  TK_AddAssign,
  TK_AndAssign,
  TK_OrAssign,
  TK_XorAssign,
  TK_LeftShiftAssign,
  TK_RightShiftAssign,
  TK_FirstAssign = TK_Assign,
  TK_LastAssign = TK_RightShiftAssign,
  TK_OpenParen,
  TK_CloseParen,
  TK_OpenBrace,
  TK_CloseBrace,
  TK_OpenBracket,
  TK_CloseBracket,
  TK_Comma,
  TK_Pound,
  TK_Question,
  TK_ThreeDots,
  TK_Semicolon,
  TK_Dot,
  TK_TwoDots,
  TK_NewLine,
  TK_Colon,
  TK_DoubleColon,
  TK_At,
  TK_Arrow,
  TK_ExprSizeof,
  TK_DocComment,
  TK_Comment,
  TK_Identifier,
  TK_UnicodeLit,
  TK_StringLit,
  TK_Error,
  TK_Float,
  TK_Integer,
  TK_Keyword,
/*END*/

  TK_Pointer     = TK_Mul,
  TK_Dereference = TK_BitAnd,

  OPEN_SCOPE = 128,
  CLOSE_SCOPE,
  SAME_SCOPE,
};

struct Token{
  Token_Kind kind;
  U32 di; // debug_id
  union{
    String string;
    struct{U8 *str; S64 len;};
  };

  union {
    U32 unicode;
    BigInt int_val;
    F64 f64_val;
    String error_val;
    Intern_String intern_val;
    S64 indent;
  };

  Intern_String file;
  S32           line;
  U8           *line_begin;
};

struct Lex_Stream{
  String stream;
  S64    iter;

  U8            *line_begin;
  Intern_String  file;
  S32            line;
  S32            inside_brace_paren;
  Array<Token *> indent_stack;
};

struct Lexer{
  Allocator *arena;
  Lex_Stream   stream;
  Array<Token> tokens;
  Intern_Table interns;
  S64 token_iter;
  U32 token_debug_ids;

  Intern_String first_op;
  Intern_String last_op ;

  Intern_String intern(String string){
    return intern_string(&interns, string);
  }
};

// Lexer::interns::map::allocator - array allocator, resizing
// Lexer::tokens                  - array allocator, resizing
//
// Parser::ast_arena                - arena for asts
// Lexer::interns::string_allocator - arena for interns
//

struct Parse_Ctx:Lexer{
  Allocator *perm; // Stores: AST, tokens, interns
  Arena     *perm_arena;
  Allocator *heap;
  Arena      stage_arena;

  Array<Ast_Type *> all_types;
  S32 type_ids;
  int lambda_ids;
  U64 unique_ids; // @Debug
  Map type_map;

  Ast_Module *language_base_module;

  Array<Ast_File    *> files;
  Array<Ast_Module  *> modules;
  Array<Ast_Decl    *> ordered_decls;
  S32 base_language_ordered_decl_len;

  Ast_Scope         *currently_parsed_scope;
  Ast_File          *currently_parsed_file;
  U32 scope_ids;
  U32 scope_visit_id;

  Array<String> module_folders;
  String module_folder;
  String exe_folder;
  String working_folder;

  S64 indent;
  String_Builder gen;
  String_Builder helper_builder;
};

function void init_type();
function void lex_init(Allocator *token_string_arena, Allocator *map_allocator, Lexer *l);
function String compile_to_c_code();
function Ast_Module *ast_module(Token *pos, Intern_String filename);
function void insert_builtin_types_into_scope(Ast_Scope *p);
function void insert_into_scope(Ast_Scope *scope, Ast_Decl *decl);
function Ast_Type *type_incomplete(Ast *ast);
function Ast_Expr *parse_expr(S64 minbp = 0);