package be.ugent.logprog.lexer

import lexer.Error
import lexer.Lexer
import lexer.TokenType
import org.junit.jupiter.api.Test
import org.junit.jupiter.api.assertThrows
import kotlin.test.assertEquals

class LexerScanTest {
    @Test
    fun scan_emptyString_returnsEOF() {
        val lexer = Lexer("")
        val tokens = lexer.scan()
        assertEquals(1, tokens.size)
        assertEquals(TokenType.EOF, tokens[0].type)
    }

    @Test
    fun scan_unknownSymbol_returnsError() {
        val lexer = Lexer("€")
        assertThrows<Error>({
            val tokens = lexer.scan()
        })
    }

    @Test
    fun scan_dot_returnsDot() {
        val lexer = Lexer(".")
        val tokens = lexer.scan()
        assertEquals(2, tokens.size)
        assertEquals(TokenType.DOT, tokens[0].type, "Expected DOT token, got ${tokens[0].type}")
        assertEquals(TokenType.EOF, tokens[1].type, "Expected EOF token, got ${tokens[1].type}")
    }
}