diff options
Diffstat (limited to 'src/lib.rs')
| -rw-r--r-- | src/lib.rs | 217 |
1 files changed, 217 insertions, 0 deletions
diff --git a/src/lib.rs b/src/lib.rs new file mode 100644 index 0000000..f728b7c --- /dev/null +++ b/src/lib.rs @@ -0,0 +1,217 @@ +use std::collections::HashMap; + +use pyo3::prelude::*; + +const KEYWORDS: [char; 5] = ['*', '_', '~', '`', '|']; +const NO_SUB_PARSING_KEYWORDS: [char; 1] = ['`']; +const QUOTE_KEYWORDS: [char; 1] = ['>']; +const BLOCK_KEYWORDS: [(char, usize); 2] = [('`', 2), ('|', 1)]; +const PLACEHOLDER: &str = "\u{200B}\u{200B}\u{200B}\u{200B}\u{200B}\u{200B}\u{200B}\u{200B}\u{200B}\u{200B}"; + +#[pyfunction] +fn format_body(body: String, new_tags: HashMap<String, (String, String)>) -> PyResult<String> { + let mut chars: Vec<char> = body.chars().collect(); + if chars.len() < 1 { + return Ok(body); + } + let styles: Vec<(String, usize, usize)> = parse_with_limits(&chars, 0, chars.len() - 1, 0); + let parse_quotes = new_tags.contains_key(&">".to_string()); + + let mut tags: Vec<(usize, String, String, bool)> = vec![]; + for style in styles { + let (keyword, start, end) = style; + if new_tags.contains_key(&keyword) { + tags.push((start, keyword.clone(), new_tags.get(&keyword).unwrap().0.clone(), false)); + tags.push((end, keyword.clone(), new_tags.get(&keyword).unwrap().1.clone(), QUOTE_KEYWORDS.contains(&keyword.chars().next().unwrap()))); + } else if keyword == ">>" && parse_quotes { + tags.push((start, keyword.clone(), "".to_string(), false)); + } + } + + tags.sort_by(|a, b| b.0.cmp(&a.0)); + + for tag in tags { + let (index, keyword, tag, is_end_quote_block) = tag; + let end = if is_end_quote_block { + index + } else if keyword == ">>" { + index + 1 + } else { + index + keyword.len() + }; + chars = [chars[..index].to_vec(), tag.chars().collect(), chars[end..].to_vec()].concat(); + } + + Ok(remove_non_escaped_backslashes(chars.into_iter().collect())) +} + +fn remove_non_escaped_backslashes(text: String) -> String { + let tmp_string = text.replace("\\\\", PLACEHOLDER); + let tmp_string = tmp_string.replace("\\", ""); + tmp_string.replace(PLACEHOLDER, "\\") +} + +fn parse_with_limits(chars: &Vec<char>, start: usize, end: usize, depth: usize) -> Vec<(String, usize, usize)> { + let mut styles = Vec::new(); + let mut index = start; + let end = end.min(chars.len() - 1); + println!("parse with limits start {}, end {}", start, end); + + while index <= end { + if preceeded_by_backslash(chars, index, start) { + index += 1; + continue; + } + + let c = chars[index]; + if c == '|' && !is_char_repeating(chars, c, index, end) { + index += 1; + continue; + } + + if QUOTE_KEYWORDS.contains(&c) { + if is_quote_start(chars, index, depth) { + let to = seek_end_of_quote(chars, index, end, depth); + styles.push((">".to_string(), index, to)); + styles.append(&mut parse_with_limits(chars, index + 1, to, depth + 1)); + index = to; + continue; + } + if depth > 0 { + styles.push((">>".to_string(), index, index + 1)); + } + index += 1; + continue; + } + + if !preceeded_by_whitespace(chars, index, start) || followed_by_whitespace(chars, index, end) { + index += 1; + continue; + } + + if !KEYWORDS.contains(&c) { + index += 1; + continue; + } + + if BLOCK_KEYWORDS.iter().any(|&(k, _)| k == c) && is_char_repeating(chars, c, index, end) { + let block_indicator_size = get_block_indicator_size(c); + match seek_end_block(chars, c, index + block_indicator_size + 1, end) { + Some(to) => { + if to != index + block_indicator_size * 2 - 1 { + let keyword = c.to_string().repeat(block_indicator_size+1); + styles.push((keyword, index, to)); + if !NO_SUB_PARSING_KEYWORDS.contains(&c) { + styles.append(&mut parse_with_limits(chars, index + block_indicator_size + 1, to - 1, depth)); + } + } + index = to + block_indicator_size; + continue; + } + None => () + } + } + + match seek_end(chars, c, index + 1, end) { + Some (to) => { + if to != index + 1 { + styles.push((c.to_string(), index, to)); + if !NO_SUB_PARSING_KEYWORDS.contains(&c) { + styles.append(&mut parse_with_limits(chars, index + 1, to - 1, depth)); + } + } + index = to; + } + None => () + } + index += 1; + } + styles +} + +fn is_char_repeating(chars: &Vec<char>, keyword: char, index: usize, end: usize) -> bool { + let block_indicator_size = get_block_indicator_size(keyword); + + (0..block_indicator_size as usize) + .all(|i| index + i <= end && chars[index + i] == keyword) +} + +fn preceeded_by_whitespace(chars: &Vec<char>, index: usize, start: usize) -> bool { + index == start || chars[index - 1].is_whitespace() +} + +fn followed_by_whitespace(chars: &Vec<char>, index: usize, end: usize) -> bool { + index >= end || chars[index + 1].is_whitespace() +} + +fn seek_end(chars: &Vec<char>, keyword: char, start: usize, end: usize) -> Option<usize> { + for i in start..=end { + let c = chars[i]; + if c == '\n' { + return None; + } + if c == keyword + && !chars[i - 1].is_whitespace() + && !preceeded_by_backslash(chars, i, start) + { + return Some(i); + } + } + None +} + +fn seek_end_of_quote(chars: &Vec<char>, start: usize, end: usize, depth: usize) -> usize { + for i in start..=end { + if chars[i] == '\n' { + if i + 2 + depth > chars.len() { + return i; + } + if chars[i + 1..=i + 1 + depth].iter().any(|&c| !QUOTE_KEYWORDS.contains(&c)) { + return i; + } + } + } + end + 1 +} + +fn seek_end_block(chars: &Vec<char>, keyword: char, start: usize, end: usize) -> Option<usize> { + for i in start..=end { + if chars[i] == keyword + && is_char_repeating(chars, keyword, i + 1, end) + && !preceeded_by_backslash(chars, i, start) + { + return Some(i); + } + } + None +} + +fn is_quote_start(chars: &Vec<char>, index: usize, depth: usize) -> bool { + index - depth == 0 || chars[index - 1 - depth] == '\n' +} + +fn preceeded_by_backslash(chars: &Vec<char>, index: usize, start: usize) -> bool { + if index == start { + return false; + } + let mut num_backslashes = 0; + while index > num_backslashes && chars[index - 1 - num_backslashes] == '\\' { + num_backslashes += 1; + } + num_backslashes % 2 == 1 +} + +fn get_block_indicator_size(keyword: char) -> usize { + for &(k, v) in BLOCK_KEYWORDS.iter() { + if k == keyword { + return v; + } + } + 1 // shouldn't ever happen +} + +#[pymodule] +fn style_parser(_py: Python, m: &PyModule) -> PyResult<()> { + m.add_function(wrap_pyfunction!(format_body, m)?)?; + Ok(()) +} |