1 files changed, 68 insertions, 0 deletions
diff --git a/src/matrix.rs b/src/matrix.rs
new file mode 100644
index 0000000..92d2eb8
--- /dev/null
+++ b/src/matrix.rs
@@ -0,0 +1,68 @@
+use pyo3::prelude::*;
+
+use crate::parser::parse_with_limits;
+
+const MATRIX_FORMATS: &[(&'static str, (&'static str, &'static str))] = &[
+    ("_", ("<em>", "</em>")),
+    ("*", ("<strong>", "</strong>")),
+    ("~", ("<strike>", "</strike>")),
+    ("`", ("<code>", "</code>")),
+    ("```", ("<pre><code>", "</code></pre>")),
+    ("```language", ("<pre><code class=\"language-{}\">", "</code></pre>")),
+    (">", ("<blockquote>", "</blockquote>")),
+    ("||", ("<span data-mx-spoiler>", "</span>")),
+];
+
+#[pyfunction]
+pub fn format_for_matrix(body: String) -> PyResult<String> {
+    let mut chars: Vec<char> = body.chars().collect();
+    if chars.len() < 1 {
+        return Ok(body);
+    }
+    let styles: Vec<(String, usize, usize, usize, usize)> = parse_with_limits(&chars, 0, chars.len() - 1, 0);
+
+    let mut tags: Vec<(usize, String, usize)> = Vec::with_capacity(styles.len() * 2);
+    for (keyword, start, remove_start, end, remove_end) in styles {
+        if MATRIX_FORMATS.iter().any(|&(k, _)| k == keyword) {
+            let opening_tag = if keyword == "```language" {
+                MATRIX_FORMATS.iter().find(|&&(k, _)| k == keyword).unwrap().1.0.clone()
+                .replace("{}", &chars[start+3..remove_start-1]
+                .into_iter()
+                .collect::<String>())
+            } else {
+                MATRIX_FORMATS.iter().find(|&&(k, _)| k == keyword).unwrap().1.0.clone().to_string()
+            };
+            tags.push((start, opening_tag, remove_start));
+            tags.push((end, MATRIX_FORMATS.iter().find(|&&(k, _)| k == keyword).unwrap().1.1.clone().to_string(), remove_end));
+        } else if keyword == ">>" || keyword == "```>" || keyword == "\\" {
+            tags.push((start, "".to_string(), start+1));
+        }
+    }
+
+    tags.sort_by(|a, b| b.0.cmp(&a.0));
+
+    let mut replace_newlines_to = chars.len();
+    for (index, tag, end) in tags {
+        if tag == "</code></pre>" {
+            // index is at \n, add 1 to skip that one
+            let substring = chars[index + 1..replace_newlines_to].into_iter().collect::<String>();
+            chars = [&chars[..index + 1], &substring.replace('\n', "<br>").chars().collect::<Vec<char>>()[..]].concat();
+        } else if tag == "<pre><code>" {
+            replace_newlines_to = index;
+        }
+
+        let tag: Vec<char> = tag.chars().collect();
+        chars = [chars[..index].to_vec(), tag.clone(), chars[end..].to_vec()].concat();
+        
+        let offset: isize = index as isize - end as isize + tag.len() as isize;
+        replace_newlines_to = if offset > 0 {
+            replace_newlines_to + offset as usize
+        } else {
+            replace_newlines_to - offset.abs() as usize
+        };
+    }
+    let substring = chars[..replace_newlines_to].into_iter().collect::<String>();
+    let text = [substring.replace('\n', "<br>"), chars[replace_newlines_to..].into_iter().collect::<String>()].concat();
+
+    Ok(text)
+}