use crate::lexers::Token;
pub struct Lexer {
input: Vec<char>,
pub position: usize,
pub read_position: usize,
pub ch: char,
}
fn is_letter(ch: char) -> bool {
ch.is_alphabetic() || ch == '_'
}
impl Lexer {
pub fn new(input: Vec<char>) -> Self {
Self {
input,
position: 0,
read_position: 0,
ch: '\0',
}
}
pub fn read_char(&mut self) {
if self.read_position >= self.input.len() {
self.ch = '\0';
} else {
self.ch = self.input[self.read_position];
}
self.position = self.read_position;
self.read_position += 1;
}
pub fn next_token(&mut self) -> Token {
let read_identifier = |l: &mut Lexer| -> Vec<char> {
let position = l.position;
while l.position < l.input.len() && is_letter(l.ch) {
l.read_char();
}
l.input[position..l.position].to_vec()
};
let read_string = |l: &mut Lexer, ch: char| -> Vec<char> {
let position = l.position;
l.read_char();
while l.position < l.input.len() && l.ch != ch {
if l.ch == '\\' {
l.read_char();
}
l.read_char();
}
l.read_char();
if l.position > l.input.len() {
l.position -= 1;
l.read_position -= 1;
}
l.input[position..l.position].to_vec()
};
let read_number = |l: &mut Lexer| -> Vec<char> {
let position = l.position;
while l.position < l.input.len() && l.ch.is_numeric() {
l.read_char();
}
l.input[position..l.position].to_vec()
};
let tok: Token;
if self.ch == '/' {
let next_id = String::from("/*").chars().collect::<Vec<_>>();
let next_position = self.position + next_id.len();
let end_id = String::from("*/").chars().collect::<Vec<_>>();
if self.position + next_id.len() < self.input.len()
&& self.input[self.position..next_position] == next_id
{
let mut identifier = next_id.clone();
next_id.iter().for_each(|_| self.read_char());
let start_position = self.position;
while self.position < self.input.len() {
if self.ch == '*' {
let end_position = self.position + end_id.len();
if end_position <= self.input.len()
&& self.input[self.position..end_position] == end_id
{
end_id.to_owned().iter().for_each(|_| self.read_char());
break;
}
}
self.read_char();
}
identifier.append(&mut self.input[start_position..self.position].to_vec());
return Token::COMMENT(identifier);
}
}
if self.read_position < self.input.len()
&& self.ch == '/'
&& self.input[self.read_position] == '/'
{
return Token::COMMENT(read_string(self, '\n'));
}
match self.ch {
'\n' => {
tok = Token::ENDL(self.ch);
}
'\0' => {
tok = Token::EOF;
}
_ => {
return if is_letter(self.ch) {
#[allow(unused_variables)]
let start_position = self.position;
#[allow(unused_mut)]
let mut identifier: Vec<char> = read_identifier(self);
if self.ch.is_numeric() {
let position = self.position;
while self.position < self.input.len() {
if self.ch == ' '
|| self.ch == ':'
|| self.ch == ','
|| self.ch == '{'
|| self.ch == '\n'
{
break;
}
self.read_char();
}
identifier.append(&mut self.input[position..self.position].to_vec());
}
match get_keyword_token(&identifier) {
Ok(keyword_token) => keyword_token,
Err(_) => {
if start_position != 0 && self.input[start_position - 1] == '.' {
let position = self.position;
while self.position < self.input.len() {
if self.ch == ' '
|| self.ch == '{'
|| self.ch == ','
|| self.ch == '\n'
{
break;
}
self.read_char();
}
identifier
.append(&mut self.input[position..self.position].to_vec());
return Token::ENTITY(identifier);
}
if self.ch == '(' {
let position = self.position;
while self.position < self.input.len() {
if self.ch == ' '
|| self.ch == ':'
|| self.ch == ';'
|| self.ch == '}'
|| self.ch == '\n'
{
break;
}
self.read_char();
}
identifier
.append(&mut self.input[position..self.position].to_vec());
return Token::IDENT(identifier);
}
if self.ch == '-' || self.ch == ':' {
let position = self.position;
while self.position < self.input.len() {
if self.ch == ' '
|| self.ch == ':'
|| self.ch == '}'
|| self.ch == '\n'
{
break;
}
self.read_char();
}
identifier
.append(&mut self.input[position..self.position].to_vec());
return Token::ENTITY(identifier);
}
if self.ch == '(' {
return Token::ENTITY(identifier);
} else if self.ch.is_whitespace() {
let mut position = self.position;
let mut ch = self.input[position];
while position < self.input.len() && ch.is_whitespace() {
position += 1;
if position < self.input.len() {
ch = self.input[position];
}
}
if ch == '(' {
return Token::ENTITY(identifier);
}
}
Token::IDENT(identifier)
}
}
} else if self.ch.is_numeric() {
let identifier: Vec<char> = read_number(self);
Token::INT(identifier)
} else if self.ch == '"' {
let str_value: Vec<char> = read_string(self, '"');
Token::STRING(str_value)
} else {
Token::ILLEGAL
}
}
}
self.read_char();
tok
}
}
pub fn get_keyword_token(identifier: &Vec<char>) -> Result<Token, String> {
let id: String = identifier.into_iter().collect();
match &id[..] {
"root" | "rgb" | "rgba" | "calc" | "media" => Ok(Token::CONSTANT(identifier.clone())),
"after" | "before" | "hover" | "not" | "focus" | "active" | "selection" | "px" | "rem" => {
Ok(Token::ENTITY(identifier.clone()))
}
"important" => Ok(Token::KEYWORD(identifier.clone())),
"html" | "body" | "div" | "span" | "applet" | "object" | "iframe" | "h1" | "h2" | "h3"
| "h4" | "h5" | "h6" | "p" | "blockquote" | "button" | "pre" | "a" | "abbr" | "acronym"
| "address" | "big" | "cite" | "code" | "del" | "dfn" | "em" | "img" | "ins" | "kbd"
| "q" | "s" | "samp" | "select" | "small" | "strike" | "strong" | "sub" | "sup" | "tt"
| "var" | "b" | "u" | "i" | "center" | "dl" | "dt" | "dd" | "ol" | "ul" | "li"
| "fieldset" | "form" | "label" | "legend" | "table" | "caption" | "tbody" | "tfoot"
| "thead" | "tr" | "th" | "td" | "article" | "canvas" | "embed" | "output" | "ruby"
| "summary" | "time" | "mark" | "audio" | "videoarticle" | "aside" | "details"
| "figcaption" | "figure" | "footer" | "header" | "hgroup" | "menu" | "nav" | "section"
| "video" | "textarea" | "input" => Ok(Token::ENTITYTAG(identifier.clone())),
_ => Err(String::from("Not a keyword")),
}
}
pub fn render_html(input: Vec<char>) -> String {
let mut l = Lexer::new(input);
l.read_char();
let mut html = String::new();
let mut line = 1;
html.push_str("<table class=\"highlight-table\">\n");
html.push_str("<tbody>\n");
html.push_str("<tr>");
html.push_str(&format!(
"<td class=\"hl-num\" data-line=\"{}\"></td><td>",
line
));
loop {
let token = l.next_token();
if token == Token::EOF {
html.push_str("</td></tr>\n");
break;
}
match token {
Token::INT(value) => {
html.push_str(&format!(
"<span class=\"hl-c\">{}</span>",
value.iter().collect::<String>()
));
}
Token::IDENT(value) => {
html.push_str(&value.iter().collect::<String>());
}
Token::STRING(value) => {
let mut s = String::new();
for ch in value {
if ch == '<' {
s.push_str("<");
} else if ch == '>' {
s.push_str(">");
} else {
s.push(ch);
}
}
html.push_str(&format!("<span class=\"hl-s\">{}</span>", s));
}
Token::ENTITY(value) => {
html.push_str(&format!(
"<span class=\"hl-en\">{}</span>",
value.iter().collect::<String>()
));
}
Token::CONSTANT(value) => {
html.push_str(&format!(
"<span class=\"hl-c\">{}</span>",
value.iter().collect::<String>()
));
}
Token::KEYWORD(value) => {
html.push_str(&format!(
"<span class=\"hl-k\">{}</span>",
value.iter().collect::<String>()
));
}
Token::ENTITYTAG(value) => {
let mut s = String::new();
for ch in value {
if ch == '<' {
s.push_str("<");
} else if ch == '>' {
s.push_str(">");
} else {
s.push(ch);
}
}
html.push_str(&format!("<span class=\"hl-ent\">{}</span>", s));
}
Token::COMMENT(value) => {
let mut lines = String::new();
for ch in value {
if ch == '<' {
lines.push_str("<");
} else if ch == '>' {
lines.push_str(">");
} else {
lines.push(ch);
}
}
let split = lines.split("\n");
let split_len = split.clone().collect::<Vec<&str>>().len();
let mut index = 0;
for val in split {
if val.len() > 1 {
html.push_str(&format!("<span class=\"hl-cmt\">{}</span>", val));
}
index = index + 1;
if index != split_len {
line = line + 1;
html.push_str("</td></tr>\n");
html.push_str(&format!(
"<tr><td class=\"hl-num\" data-line=\"{}\"></td><td>",
line
));
}
}
}
Token::ENDL(_) => {
line = line + 1;
html.push_str("</td></tr>\n");
html.push_str(&format!(
"<tr><td class=\"hl-num\" data-line=\"{}\"></td><td>",
line
));
}
_ => {
html.push(l.ch);
l.read_char();
}
}
}
html.push_str("</tbody>\n");
html.push_str("</table>");
html
}