scanner.h

#pragma once

#include "objects/customarray.h"
#include "utf8.h"

class Scanner;

typedef struct Token {

	typedef enum {
		TOKEN_LEFT_PAREN,
		TOKEN_RIGHT_PAREN,
		TOKEN_LEFT_BRACE,
		TOKEN_RIGHT_BRACE,
		TOKEN_LEFT_SQUARE,
		TOKEN_RIGHT_SQUARE,
		TOKEN_SUBSCRIPT, // []

		TOKEN_BANG,
		TOKEN_BANG_EQUAL,
		TOKEN_COMMA,
		TOKEN_DOT,
		TOKEN_DOT_DOT,
		TOKEN_COLON,

		TOKEN_EQUAL,
		TOKEN_EQUAL_EQUAL,
		TOKEN_GREATER,
		TOKEN_GREATER_EQUAL,
		TOKEN_GREATER_GREATER,
		TOKEN_LESS,
		TOKEN_LESS_EQUAL,
		TOKEN_LESS_LESS,

		TOKEN_MINUS,
		TOKEN_PLUS,
		TOKEN_SEMICOLON,
		TOKEN_SLASH,
		TOKEN_STAR,
		TOKEN_PERCEN,
		TOKEN_CARET,
		TOKEN_AT,
		TOKEN_PIPE,
		TOKEN_AMPERSAND,
		TOKEN_TILDE,

		TOKEN_PLUS_PLUS,
		TOKEN_MINUS_MINUS,

		TOKEN_IDENTIFIER,
		TOKEN_STRING,
		TOKEN_NUMBER,
		TOKEN_HEX,
		TOKEN_OCT,
		TOKEN_BIN,

#define KEYWORD(x, y) TOKEN_##x,
#include "keywords.h"
#undef KEYWORD

		TOKEN_ERROR,
		TOKEN_EOF
	} Type;
	enum HighlightType { INFO = 0, WARN = 1, ERR = 2 };
	Type       type;
	Utf8Source start;
	Utf8Source source;
	int        length;
	int        line;
	Utf8Source fileName;

	Token(Type t, Utf8Source s, Utf8Source r, int l, int ln, Utf8Source f)
	    : type(t), start(s), source(r), length(l), line(ln), fileName(f) {}
	Token()
	    : type(TOKEN_EOF), start((void *)NULL), source((void *)NULL), length(0),
	      line(0), fileName((void *)NULL) {}
	static Token from(Type t, Scanner *s);
	static Token errorToken(const char *message, Scanner *s);
	void         highlight(bool showFileName = false, const char *prefix = NULL,
	                       HighlightType htype = HighlightType::INFO) const;
	static const char *TokenNames[];
	static const char *FormalNames[];
	bool               isOperator();
	static Token       PlaceholderToken;
} Token;

class Scanner {
  private:
	Utf8Source         source;
	Utf8Source         tokenStart;
	Utf8Source         current;
	Utf8Source         fileName;
	int                line;
	int                scanErrors;
	CustomArray<Token> tokenList;

	// Returns 1 if `c` is an English letter or underscore.
	static bool isAlpha(utf8_int32_t c);

	// Returns 1 if `c` is a digit.
	static bool isDigit(utf8_int32_t c);

	// Returns 1 if `c` is an English letter, underscore, or digit.
	static bool isAlphaNumeric(utf8_int32_t c);

	bool         isAtEnd();
	utf8_int32_t advance();
	utf8_int32_t peek();
	utf8_int32_t peekNext();
	bool         match(utf8_int32_t expected);
	Token        identifier();
	Token        number();
	Token        hexadecimal();
	Token        octal();
	Token        binary();
	Token        str();
	int          skipEmptyLine();

  public:
	Scanner(const void *source, const void *file);
	Scanner(const void *file);
	Token                     scanNextToken();
	const CustomArray<Token> &scanAllTokens();
	bool                      hasScanErrors();

	friend Token;
};