package main

import "fmt"

//go:generate stringer -type tokenType -linecomment -trimprefix tokenType
type tokenType int

const (
	// single char tokens

	tokenTypeLeftParen tokenType = iota
	tokenTypeRightParen
	tokenTypeLeftBrace
	tokenTypeRightBrace
	tokenTypeComma
	tokenTypeDot
	tokenTypeMinus
	tokenTypePlus
	tokenTypeSemicolon
	tokenTypeSlash
	tokenTypeStar

	// 1-2 char token

	tokenTypeBang
	tokenTypeBangEq
	tokenTypeEqual
	tokenTypeEqualEqual
	tokenTypeGreater
	tokenTypeGreaterEq
	tokenTypeLess
	tokenTypeLessEq

	// literals

	tokenTypeIdentifier
	tokenTypeString
	tokenTypeNumber

	// keywords

	tokenTypeAnd
	tokenTypeClass
	tokenTypeElse
	tokenTypeFalse
	tokenTypeFun
	tokenTypeFor
	tokenTypeIf
	tokenTypeNil
	tokenTypeOr
	tokenTypePrint
	tokenTypeReturn
	tokenTypeSuper
	tokenTypeThis
	tokenTypeTrue
	tokenTypeVar
	tokenTypeWhile

	tokenTypeEOF
)

var keywordTokenTypes = []tokenType{
	tokenTypeClass,
	tokenTypeFun,
	tokenTypeVar,
	tokenTypeFor,
	tokenTypeIf,
	tokenTypeReturn,
	tokenTypeWhile,
	tokenTypePrint,
}

type token struct {
	Type    tokenType
	Lexeme  string
	Literal any
	Line    int
}

func (t token) String() string {
	return fmt.Sprintf("%s %s %+v", t.Type, t.Lexeme, t.Literal)
}

func isKeyword(token *token) bool {
	for _, kt := range keywordTokenTypes {
		if token.Type == kt {
			return true
		}
	}
	return false
}