#ifndef CS241_SCANNER_H
#define CS241_SCANNER_H
#include <string>
#include <vector>
#include <set>
#include <cstdint>
#include <ostream>

class Token;

std::vector<Token> scan(const std::string &input);

class Token {
    public:
        enum Kind {
            ID = 0, NUM, LPAREN, RPAREN,
            LBRACE, RBRACE, RETURN,
            IF, ELSE, WHILE,
            PRINTLN, WAIN, BECOMES,
            INT, EQ, NE, LT, GT,
            LE, GE, PLUS, MINUS,
            STAR, SLASH, PCT, COMMA,
            SEMI, NEW, DELETE, 
            LBRACK, RBRACK, AMP, NUL,
            WHITESPACE
        };

    private:
        Kind kind;
        std::string lexeme;

    public:
        Token(Kind kind, std::string lexeme);

        Kind getKind() const;
        const std::string &getLexeme() const;
        const std::string getString() const;

        int64_t toNumber() const;
};

std::ostream &operator<<(std::ostream &out, const Token &tok);

class ScanningFailure {
    std::string message;

  public:
    ScanningFailure(std::string message);

    // Returns the message associated with the exception.
    const std::string &what() const;
};

#endif