Function cleanup_empty_styles

src/text_input.rs:2161–2313

Remove empty style tags (`{style|}`) from the raw string, EXCEPT those that contain the cursor. A cursor is "inside" an empty style tag if its visual position equals the visual position of that tag's content area. Returns the new raw string and the (possibly adjusted) visual cursor position.

(raw: &str, cursor_visual_pos: usize)

    ///
    /// Returns the new raw string and the (possibly adjusted) visual cursor position.
    pub fn cleanup_empty_styles(raw: &str, cursor_visual_pos: usize) -> (String, usize) {
        let chars: Vec<char> = raw.chars().collect();
        let len = chars.len();
        let mut result = String::with_capacity(raw.len());
        let mut i = 0;
        let mut visual = 0usize;
        let mut escaped = false;
        let mut cursor_adj = cursor_visual_pos;

        // We need to track style nesting to correctly identify empty tags
        while i < len {
            let c = chars[i];

            if escaped {
                result.push(c);
                visual += 1;
                escaped = false;
                i += 1;
                continue;
            }

            match c {
                '\\' => {
                    escaped = true;
                    result.push(c);
                    i += 1;
                }
                '{' => {
                    // Look ahead: find the matching `|`, then check if there's content
                    // before the closing `}`. Pattern: `{...| <content> }`
                    // Find the `|` that ends this style definition
                    let mut j = i + 1;
                    let mut style_escaped = false;
                    let mut found_pipe = false;
                    while j < len {
                        if style_escaped {
                            style_escaped = false;
                            j += 1;
                            continue;
                        }
                        if chars[j] == '\\' {
                            style_escaped = true;
                            j += 1;
                            continue;
                        }
                        if chars[j] == '|' {
                            found_pipe = true;
                            j += 1; // j now points to first char after `|`
                            break;
                        }
                        if chars[j] == '{' {
                            // Nested `{` inside style def — not valid but push through
                            j += 1;
                            continue;
                        }
                        j += 1;
                    }