#include "lexer.h"
#include <string.h>
#include <stdlib.h>
#include <stdio,h>

Lexer initLexer(char *source) {
	Lexer newLexer = {
		.source = source,
		.position = -1,
		.readPosition = 0,
		.lineNumber = 1,
		.currentChar = '\0'
	};
	return newLexer;
}

void readChar(Lexer *lexer) {
	if (lexer->readPosition >= strlen(lexer->source))
		lexer->currentChar = '\0';
	else
		lexer->currentChar = lexer->source[lexer->readPosition];

	lexer->position = lexer->readPosition;
	lexer->readPosition++;
}

void skipWhitespace(Lexer *lexer) {
	switch (lexer->currentChar)
	{
	case ' ':
	case '\t':
	case '\n':
	case '\r':
		if (lexer->currentChar == '\n')
			lexer->lineNumber++;		

		readChar(lexer);
		break;
	
	default:
		break;
	}
	
}

Token nextToken(Lexer *lexer) {
	//Token tok;
	skipWhitespace(lexer);

	switch (lexer->currentChar)
	{
	case '+':
		return NEW_TOKEN(lexer, PLUS, "+");
		break;
	case '-':
		return NEW_TOKEN(lexer, MINUS, "-");
		break;
	case '*':
		return NEW_TOKEN(lexer, ASTERISK, "*");
		break;
	case '/':
		return NEW_TOKEN(lexer, SLASH, "/");
		break;
	case '%':
		return NEW_TOKEN(lexer, MODULUS, "%");
		break;
	case '^':
		return NEW_TOKEN(lexer, POW, "^");
		break;
	case '(':
		return NEW_TOKEN(lexer, LPAREN, "(");
		break;
	case ')':
		return NEW_TOKEN(lexer, RPAREN, ")");
		break;
	case '\0':
		return NEW_TOKEN(lexer, EOF, "");
		break;
	
	default:
		if (isdigit())

		break;
	}

	//return tok;
}