git.r.bdr.sh - rbdr/gema_texto/blame_incremental - src/html_renderer.rs

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<u8>,
) -> 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("</ul>\n"),
            },
            GeminiLine::Quote(_) => match line {
                GeminiLine::Quote(_) => {}
                _ => html.push_str("</blockquote>\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("</section>\n");

                if open_heading == *level {
                    break;
                }
            }
            heading_stack.push(*level);
            html.push_str(&format!("<section class=\"h{level}\">\n"));
        }
        GeminiLine::ListItem(_) => match last_line {
            Some(GeminiLine::ListItem(_)) => {}
            _ => html.push_str("<ul>\n"),
        },
        GeminiLine::Quote(_) => match last_line {
            Some(GeminiLine::Quote(_)) => {}
            _ => html.push_str("<blockquote>\n"),
        },
        _ => {}
    }

    html
}

fn line_content(line: &GeminiLine) -> String {
    match line {
        GeminiLine::Text(content, false) => format!("<p>{content}</p>"),
        GeminiLine::Link(url, text) => {
            let processed_url;
            if !url.starts_with("gemini:") && url.ends_with(".gmi") {
                processed_url = url.replace(".gmi", ".html");
            } else {
                processed_url = url.to_string();
            }
            let display = if text.is_empty() {
                &processed_url
            } else {
                text
            };
            format!("<p class=\"a\"><a href=\"{processed_url}\">{display}</a></p>")
        }
        GeminiLine::Heading(level, content) => format!("<h{level}>{content}</h{level}>"),
        GeminiLine::ListItem(content) => format!("<li>{content}</li>"),
        GeminiLine::PreformattedToggle(true, alt_text) => {
            format!("<pre aria-label=\"{alt_text}\">")
        }
        GeminiLine::PreformattedToggle(false, _) => "</pre>".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("</ul>\n"),
        Some(GeminiLine::Quote(_)) => html.push_str("</blockquote>\n"),
        _ => {}
    }

    for _ in heading_stack {
        html.push_str("</section>\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), "<p>Hello world</p>\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),
            "<section class=\"h1\">\n\
             <h1>Top</h1>\n\
             <section class=\"h2\">\n\
             <h2>Sub</h2>\n\
             <section class=\"h3\">\n\
             <h3>SubSub</h3>\n\
             </section>\n\
             </section>\n\
             <section class=\"h2\">\n\
             <h2>Another Sub</h2>\n\
             </section>\n\
             </section>\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),
            "<ul>\n\
             <li>First</li>\n\
             <li>Second</li>\n\
             </ul>\n\
             <p>Break</p>\n\
             <ul>\n\
             <li>New list</li>\n\
             </ul>\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),
            "<blockquote>\n\
             First quote\n\
             Still quoting\n\
             </blockquote>\n\
             <p>Normal text</p>\n\
             <blockquote>\n\
             New quote\n\
             </blockquote>\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),
            "<pre aria-label=\"code\">\n\
             let x = 42;\n\
             </pre>\n"
        );
    }

    #[test]
    fn test_links() {
        let input = vec![
            GeminiLine::Link("gemini://hi.gmi".to_string(), "Example".to_string()),
            GeminiLine::Link("/hi.gmi/kidding".to_string(), "Example".to_string()),
            GeminiLine::Link("/hi.gmi".to_string(), "Example".to_string()),
            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),
            "<p class=\"a\"><a href=\"gemini://hi.gmi\">Example</a></p>\n\
             <p class=\"a\"><a href=\"/hi.gmi/kidding\">Example</a></p>\n\
             <p class=\"a\"><a href=\"/hi.html\">Example</a></p>\n\
             <p class=\"a\"><a href=\"https://example.com\">Example</a></p>\n\
             <p class=\"a\"><a href=\"https://rust-lang.org\">https://rust-lang.org</a></p>\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),
            "<section class=\"h1\">\n\
             <h1>Title</h1>\n\
             <p>Intro</p>\n\
             <section class=\"h2\">\n\
             <h2>Section</h2>\n\
             <ul>\n\
             <li>Point 1</li>\n\
             <li>Point 2</li>\n\
             </ul>\n\
             <blockquote>\n\
             Important quote\n\
             </blockquote>\n\
             </section>\n\
             <section class=\"h2\">\n\
             <h2>Another Section</h2>\n\
             </section>\n\
             </section>\n"
        );
    }

    #[test]
    fn test_empty_input() {
        let input = Vec::new();
        assert_eq!(render_html(&input), "");
    }
}
Commit	Line	Data
	1	use crate::gemini_parser::GeminiLine;
	2
	3	/// Renders HTML from a vector of `GeminiLine` elements.
	4	///
	5	/// # Arguments
	6	/// * `lines` - Vector of `GeminiLine` elements to render
	7	///
	8	/// # Returns
	9	/// A String containing the rendered HTML.
	10	///
	11	/// # Examples
	12	/// ```
	13	/// use std::fs::read_to_string;
	14	/// use gema_texto::gemini_parser::parse;
	15	/// use gema_texto::html_renderer::render_html;
	16	///
	17	/// let gemini_source = "\
	18	/// # Hello
	19	/// This is some gemini text!
	20	/// => https://test Go to the test page.
	21	/// ";
	22	///
	23	/// let gemini_lines = parse(&gemini_source);
	24	/// let html_source = render_html(&gemini_lines);
	25	/// println!("{html_source}");
	26	/// ```
	27	#[must_use]
	28	pub fn render_html(lines: &[GeminiLine]) -> String {
	29	let mut heading_stack = Vec::new();
	30	let mut last_line: Option<&GeminiLine> = None;
	31	let mut result = String::new();
	32
	33	for line in lines {
	34	result.push_str(&line_preamble(line, last_line, &mut heading_stack));
	35	result.push_str(&line_content(line));
	36	result.push('\n');
	37	last_line = Some(line);
	38	}
	39
	40	result.push_str(&finalize_html(&heading_stack, last_line));
	41	result
	42	}
	43
	44	fn line_preamble(
	45	line: &GeminiLine,
	46	last_line: Option<&GeminiLine>,
	47	heading_stack: &mut Vec<u8>,
	48	) -> String {
	49	let mut html = String::new();
	50
	51	if let Some(last_line) = last_line {
	52	match last_line {
	53	GeminiLine::ListItem(_) => match line {
	54	GeminiLine::ListItem(_) => {}
	55	_ => html.push_str("</ul>\n"),
	56	},
	57	GeminiLine::Quote(_) => match line {
	58	GeminiLine::Quote(_) => {}
	59	_ => html.push_str("</blockquote>\n"),
	60	},
	61	_ => {}
	62	}
	63	}
	64
	65	match line {
	66	GeminiLine::Heading(level, _) => {
	67	while let Some(open_heading) = heading_stack.pop() {
	68	// You just encountered a more important heading.
	69	// Put it back. Desist.
	70	if open_heading < *level {
	71	heading_stack.push(open_heading);
	72	break;
	73	}
	74
	75	html.push_str("</section>\n");
	76
	77	if open_heading == *level {
	78	break;
	79	}
	80	}
	81	heading_stack.push(*level);
	82	html.push_str(&format!("<section class=\"h{level}\">\n"));
	83	}
	84	GeminiLine::ListItem(_) => match last_line {
	85	Some(GeminiLine::ListItem(_)) => {}
	86	_ => html.push_str("<ul>\n"),
	87	},
	88	GeminiLine::Quote(_) => match last_line {
	89	Some(GeminiLine::Quote(_)) => {}
	90	_ => html.push_str("<blockquote>\n"),
	91	},
	92	_ => {}
	93	}
	94
	95	html
	96	}
	97
	98	fn line_content(line: &GeminiLine) -> String {
	99	match line {
	100	GeminiLine::Text(content, false) => format!("<p>{content}</p>"),
	101	GeminiLine::Link(url, text) => {
	102	let processed_url;
	103	if !url.starts_with("gemini:") && url.ends_with(".gmi") {
	104	processed_url = url.replace(".gmi", ".html");
	105	} else {
	106	processed_url = url.to_string();
	107	}
	108	let display = if text.is_empty() {
	109	&processed_url
	110	} else {
	111	text
	112	};
	113	format!("<p class=\"a\"><a href=\"{processed_url}\">{display}</a></p>")
	114	}
	115	GeminiLine::Heading(level, content) => format!("<h{level}>{content}</h{level}>"),
	116	GeminiLine::ListItem(content) => format!("<li>{content}</li>"),
	117	GeminiLine::PreformattedToggle(true, alt_text) => {
	118	format!("<pre aria-label=\"{alt_text}\">")
	119	}
	120	GeminiLine::PreformattedToggle(false, _) => "</pre>".to_string(),
	121	GeminiLine::Text(content, true) \| GeminiLine::Quote(content) => content.to_string(),
	122	}
	123	}
	124
	125	fn finalize_html(heading_stack: &[u8], last_line: Option<&GeminiLine>) -> String {
	126	let mut html = String::new();
	127
	128	match last_line {
	129	Some(GeminiLine::ListItem(_)) => html.push_str("</ul>\n"),
	130	Some(GeminiLine::Quote(_)) => html.push_str("</blockquote>\n"),
	131	_ => {}
	132	}
	133
	134	for _ in heading_stack {
	135	html.push_str("</section>\n");
	136	}
	137
	138	html
	139	}
	140
	141	#[cfg(test)]
	142	mod tests {
	143	use super::*;
	144
	145	#[test]
	146	fn test_simple_text() {
	147	let input = vec![GeminiLine::Text("Hello world".to_string(), false)];
	148	assert_eq!(render_html(&input), "<p>Hello world</p>\n");
	149	}
	150
	151	#[test]
	152	fn test_heading_nesting() {
	153	let input = vec![
	154	GeminiLine::Heading(1, "Top".to_string()),
	155	GeminiLine::Heading(2, "Sub".to_string()),
	156	GeminiLine::Heading(3, "SubSub".to_string()),
	157	GeminiLine::Heading(2, "Another Sub".to_string()),
	158	];
	159	assert_eq!(
	160	render_html(&input),
	161	"<section class=\"h1\">\n\
	162	<h1>Top</h1>\n\
	163	<section class=\"h2\">\n\
	164	<h2>Sub</h2>\n\
	165	<section class=\"h3\">\n\
	166	<h3>SubSub</h3>\n\
	167	</section>\n\
	168	</section>\n\
	169	<section class=\"h2\">\n\
	170	<h2>Another Sub</h2>\n\
	171	</section>\n\
	172	</section>\n"
	173	);
	174	}
	175
	176	#[test]
	177	fn test_list_transitions() {
	178	let input = vec![
	179	GeminiLine::ListItem("First".to_string()),
	180	GeminiLine::ListItem("Second".to_string()),
	181	GeminiLine::Text("Break".to_string(), false),
	182	GeminiLine::ListItem("New list".to_string()),
	183	];
	184	assert_eq!(
	185	render_html(&input),
	186	"<ul>\n\
	187	<li>First</li>\n\
	188	<li>Second</li>\n\
	189	</ul>\n\
	190	<p>Break</p>\n\
	191	<ul>\n\
	192	<li>New list</li>\n\
	193	</ul>\n"
	194	);
	195	}
	196
	197	#[test]
	198	fn test_quote_transitions() {
	199	let input = vec![
	200	GeminiLine::Quote("First quote".to_string()),
	201	GeminiLine::Quote("Still quoting".to_string()),
	202	GeminiLine::Text("Normal text".to_string(), false),
	203	GeminiLine::Quote("New quote".to_string()),
	204	];
	205	assert_eq!(
	206	render_html(&input),
	207	"<blockquote>\n\
	208	First quote\n\
	209	Still quoting\n\
	210	</blockquote>\n\
	211	<p>Normal text</p>\n\
	212	<blockquote>\n\
	213	New quote\n\
	214	</blockquote>\n"
	215	);
	216	}
	217
	218	#[test]
	219	fn test_preformatted() {
	220	let input = vec![
	221	GeminiLine::PreformattedToggle(true, "code".to_string()),
	222	GeminiLine::Text("let x = 42;".to_string(), true),
	223	GeminiLine::PreformattedToggle(false, String::new()),
	224	];
	225	assert_eq!(
	226	render_html(&input),
	227	"<pre aria-label=\"code\">\n\
	228	let x = 42;\n\
	229	</pre>\n"
	230	);
	231	}
	232
	233	#[test]
	234	fn test_links() {
	235	let input = vec![
	236	GeminiLine::Link("gemini://hi.gmi".to_string(), "Example".to_string()),
	237	GeminiLine::Link("/hi.gmi/kidding".to_string(), "Example".to_string()),
	238	GeminiLine::Link("/hi.gmi".to_string(), "Example".to_string()),
	239	GeminiLine::Link("https://example.com".to_string(), "Example".to_string()),
	240	GeminiLine::Link("https://rust-lang.org".to_string(), String::new()),
	241	];
	242	assert_eq!(
	243	render_html(&input),
	244	"<p class=\"a\"><a href=\"gemini://hi.gmi\">Example</a></p>\n\
	245	<p class=\"a\"><a href=\"/hi.gmi/kidding\">Example</a></p>\n\
	246	<p class=\"a\"><a href=\"/hi.html\">Example</a></p>\n\
	247	<p class=\"a\"><a href=\"https://example.com\">Example</a></p>\n\
	248	<p class=\"a\"><a href=\"https://rust-lang.org\">https://rust-lang.org</a></p>\n"
	249	);
	250	}
	251
	252	#[test]
	253	fn test_complex_nesting() {
	254	let input = vec![
	255	GeminiLine::Heading(1, "Title".to_string()),
	256	GeminiLine::Text("Intro".to_string(), false),
	257	GeminiLine::Heading(2, "Section".to_string()),
	258	GeminiLine::ListItem("Point 1".to_string()),
	259	GeminiLine::ListItem("Point 2".to_string()),
	260	GeminiLine::Quote("Important quote".to_string()),
	261	GeminiLine::Heading(2, "Another Section".to_string()),
	262	];
	263	assert_eq!(
	264	render_html(&input),
	265	"<section class=\"h1\">\n\
	266	<h1>Title</h1>\n\
	267	<p>Intro</p>\n\
	268	<section class=\"h2\">\n\
	269	<h2>Section</h2>\n\
	270	<ul>\n\
	271	<li>Point 1</li>\n\
	272	<li>Point 2</li>\n\
	273	</ul>\n\
	274	<blockquote>\n\
	275	Important quote\n\
	276	</blockquote>\n\
	277	</section>\n\
	278	<section class=\"h2\">\n\
	279	<h2>Another Section</h2>\n\
	280	</section>\n\
	281	</section>\n"
	282	);
	283	}
	284
	285	#[test]
	286	fn test_empty_input() {
	287	let input = Vec::new();
	288	assert_eq!(render_html(&input), "");
	289	}
	290	}