From 8beb2bfa1af988442550c9e6999d924dd14b5236 Mon Sep 17 00:00:00 2001 From: Ruben Beltran del Rio Date: Sat, 4 Jan 2025 23:04:42 +0100 Subject: Add the library --- src/html_renderer.rs | 274 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 274 insertions(+) create mode 100644 src/html_renderer.rs (limited to 'src/html_renderer.rs') diff --git a/src/html_renderer.rs b/src/html_renderer.rs new file mode 100644 index 0000000..e513533 --- /dev/null +++ b/src/html_renderer.rs @@ -0,0 +1,274 @@ +use crate::gemini_parser::GeminiLine; + +/// Renders HTML from a vector of `GeminiLine` elements. +/// +/// # Arguments +/// * `lines` - Vector of `GeminiLine` elements to render +/// +/// # Returns +/// A String containing the rendered HTML. +/// +/// # Examples +/// ``` +/// use std::fs::read_to_string; +/// use gema_texto::gemini_parser::parse; +/// use gema_texto::html_renderer::render_html; +/// +/// let gemini_source = "\ +/// # Hello +/// This is some gemini text! +/// => https://test Go to the test page. +/// "; +/// +/// let gemini_lines = parse(&gemini_source); +/// let html_source = render_html(&gemini_lines); +/// println!("{html_source}"); +/// ``` +#[must_use] +pub fn render_html(lines: &[GeminiLine]) -> String { + let mut heading_stack = Vec::new(); + let mut last_line: Option<&GeminiLine> = None; + let mut result = String::new(); + + for line in lines { + result.push_str(&line_preamble(line, last_line, &mut heading_stack)); + result.push_str(&line_content(line)); + result.push('\n'); + last_line = Some(line); + } + + result.push_str(&finalize_html(&heading_stack, last_line)); + result +} + +fn line_preamble( + line: &GeminiLine, + last_line: Option<&GeminiLine>, + heading_stack: &mut Vec, +) -> String { + let mut html = String::new(); + + if let Some(last_line) = last_line { + match last_line { + GeminiLine::ListItem(_) => match line { + GeminiLine::ListItem(_) => {} + _ => html.push_str("\n"), + }, + GeminiLine::Quote(_) => match line { + GeminiLine::Quote(_) => {} + _ => html.push_str("\n"), + }, + _ => {} + } + } + + match line { + GeminiLine::Heading(level, _) => { + while let Some(open_heading) = heading_stack.pop() { + // You just encountered a more important heading. + // Put it back. Desist. + if open_heading < *level { + heading_stack.push(open_heading); + break; + } + + html.push_str("\n"); + + if open_heading == *level { + break; + } + } + heading_stack.push(*level); + html.push_str(&format!("
\n")); + } + GeminiLine::ListItem(_) => match last_line { + Some(GeminiLine::ListItem(_)) => {} + _ => html.push_str("
    \n"), + }, + GeminiLine::Quote(_) => match last_line { + Some(GeminiLine::Quote(_)) => {} + _ => html.push_str("
    \n"), + }, + _ => {} + } + + html +} + +fn line_content(line: &GeminiLine) -> String { + match line { + GeminiLine::Text(content, false) => format!("

    {content}

    "), + GeminiLine::Link(url, text) => { + let display = if text.is_empty() { url } else { text }; + format!("

    {display}

    ") + } + GeminiLine::Heading(level, content) => format!("{content}"), + GeminiLine::ListItem(content) => format!("
  • {content}
    • "), + GeminiLine::PreformattedToggle(true, alt_text) => { + format!("
    ")
+        }
+        GeminiLine::PreformattedToggle(false, _) => "
    ".to_string(), + GeminiLine::Text(content, true) | GeminiLine::Quote(content) => content.to_string(), + } +} + +fn finalize_html(heading_stack: &[u8], last_line: Option<&GeminiLine>) -> String { + let mut html = String::new(); + + match last_line { + Some(GeminiLine::ListItem(_)) => html.push_str("
\n"), + Some(GeminiLine::Quote(_)) => html.push_str("\n"), + _ => {} + } + + for _ in heading_stack { + html.push_str("
\n"); + } + + html +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn test_simple_text() { + let input = vec![GeminiLine::Text("Hello world".to_string(), false)]; + assert_eq!(render_html(&input), "

Hello world

\n"); + } + + #[test] + fn test_heading_nesting() { + let input = vec![ + GeminiLine::Heading(1, "Top".to_string()), + GeminiLine::Heading(2, "Sub".to_string()), + GeminiLine::Heading(3, "SubSub".to_string()), + GeminiLine::Heading(2, "Another Sub".to_string()), + ]; + assert_eq!( + render_html(&input), + "
\n\ +

Top

\n\ +
\n\ +

Sub

\n\ +
\n\ +

SubSub

\n\ +
\n\ +
\n\ +
\n\ +

Another Sub

\n\ +
\n\ +
\n" + ); + } + + #[test] + fn test_list_transitions() { + let input = vec![ + GeminiLine::ListItem("First".to_string()), + GeminiLine::ListItem("Second".to_string()), + GeminiLine::Text("Break".to_string(), false), + GeminiLine::ListItem("New list".to_string()), + ]; + assert_eq!( + render_html(&input), + "\n\ +

Break

\n\ + \n" + ); + } + + #[test] + fn test_quote_transitions() { + let input = vec![ + GeminiLine::Quote("First quote".to_string()), + GeminiLine::Quote("Still quoting".to_string()), + GeminiLine::Text("Normal text".to_string(), false), + GeminiLine::Quote("New quote".to_string()), + ]; + assert_eq!( + render_html(&input), + "
\n\ + First quote\n\ + Still quoting\n\ +
\n\ +

Normal text

\n\ +
\n\ + New quote\n\ +
\n" + ); + } + + #[test] + fn test_preformatted() { + let input = vec![ + GeminiLine::PreformattedToggle(true, "code".to_string()), + GeminiLine::Text("let x = 42;".to_string(), true), + GeminiLine::PreformattedToggle(false, String::new()), + ]; + assert_eq!( + render_html(&input), + "
\n\
+             let x = 42;\n\
+
\n" + ); + } + + #[test] + fn test_links() { + let input = vec![ + GeminiLine::Link("https://example.com".to_string(), "Example".to_string()), + GeminiLine::Link("https://rust-lang.org".to_string(), String::new()), + ]; + assert_eq!( + render_html(&input), + "

Example

\n\ +

https://rust-lang.org

\n" + ); + } + + #[test] + fn test_complex_nesting() { + let input = vec![ + GeminiLine::Heading(1, "Title".to_string()), + GeminiLine::Text("Intro".to_string(), false), + GeminiLine::Heading(2, "Section".to_string()), + GeminiLine::ListItem("Point 1".to_string()), + GeminiLine::ListItem("Point 2".to_string()), + GeminiLine::Quote("Important quote".to_string()), + GeminiLine::Heading(2, "Another Section".to_string()), + ]; + assert_eq!( + render_html(&input), + "
\n\ +

Title

\n\ +

Intro

\n\ +
\n\ +

Section

\n\ +
    \n\ +
  • Point 1
    • \n\ +
  • Point 2
    • \n\ +
\n\ +
\n\ + Important quote\n\ +
\n\ +
\n\ +
\n\ +

Another Section

\n\ +
\n\ +
\n" + ); + } + + #[test] + fn test_empty_input() { + let input = Vec::new(); + assert_eq!(render_html(&input), ""); + } +} -- cgit