New template engine

Cargo.lock

@@ -2,15 +2,6 @@
 # It is not intended for manual editing.
 version = 4
 
-[[package]]
-name = "aho-corasick"
-version = "1.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e60d3430d3a69478ad0993f19238d2df97c507009a52b3c10addcd7f6bcb916"
-dependencies = [
- "memchr",
-]
-
 [[package]]
 name = "android_system_properties"
 version = "0.1.5"
@@ -112,7 +103,6 @@ dependencies = [
  "chrono",
  "once_cell",
  "pulldown-cmark",
- "regex",
  "serde",
  "tokio",
  "tower 0.4.13",
@@ -526,35 +516,6 @@ dependencies = [
  "bitflags",
 ]
 
-[[package]]
-name = "regex"
-version = "1.12.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "843bc0191f75f3e22651ae5f1e72939ab2f72a4bc30fa80a066bd66edefc24d4"
-dependencies = [
- "aho-corasick",
- "memchr",
- "regex-automata",
- "regex-syntax",
-]
-
-[[package]]
-name = "regex-automata"
-version = "0.4.13"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5276caf25ac86c8d810222b3dbb938e512c55c6831a10f3e6ed1c93b84041f1c"
-dependencies = [
- "aho-corasick",
- "memchr",
- "regex-syntax",
-]
-
-[[package]]
-name = "regex-syntax"
-version = "0.8.8"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a2d987857b319362043e95f5353c0535c1f58eec5336fdfcf626430af7def58"
-
 [[package]]
 name = "rustversion"
 version = "1.0.22"

Cargo.toml

@@ -11,5 +11,4 @@ tower-http = { version = "0.5", features = ["fs"] }
 pulldown-cmark = "0.12"
 serde = { version = "1.0", features = ["derive"] }
 chrono = "0.4"
-regex = "1.10"
 once_cell = "1.19"

src/template_engine.rs

@@ -1,5 +1,5 @@
 use crate::post_manager::PostManager;
-use regex::Regex;
+use std::collections::HashMap;
 use std::fs;
 
 pub fn render_template(
@@ -7,105 +7,195 @@ pub fn render_template(
     post_manager: &PostManager,
     current_post: Option<&str>,
 ) -> Result<String, String> {
-    let mut result = template.to_string();
+    parse_template(template, post_manager, current_post, 0)
+}
 
-    // Process includes first
-    result = process_includes(&result)?;
-
-    // Process post-html tag
-    if let Some(post_name) = current_post {
-        result = process_post_html(&result, post_manager, post_name)?;
+fn parse_template(
+    template: &str,
+    post_manager: &PostManager,
+    current_post: Option<&str>,
+    depth: usize,
+) -> Result<String, String> {
+    const MAX_DEPTH: usize = 10;
+    if depth > MAX_DEPTH {
+        return Err("Too many nested includes (max 10)".to_string());
     }
 
-    // Process post-list tag
-    result = process_post_list(&result, post_manager)?;
+    let mut result = String::new();
+    let chars: Vec<char> = template.chars().collect();
+    let mut i = 0;
+
+    while i < chars.len() {
+        // Check for $< tag start
+        if i + 1 < chars.len() && chars[i] == '$' && chars[i + 1] == '<' {
+            // Try to parse tag
+            if let Some((tag_name, attrs, end_pos)) = parse_tag(&chars, i) {
+                // Process tag immediately based on type
+                let content = process_tag(&tag_name, &attrs, post_manager, current_post, depth)?;
+                result.push_str(&content);
+                i = end_pos;
+                continue;
+            }
+        }
+
+        // Regular character
+        result.push(chars[i]);
+        i += 1;
+    }
 
     Ok(result)
 }
 
-fn process_includes(template: &str) -> Result<String, String> {
-    let include_regex = Regex::new(r#"\$<include\s+src="([^"]+)"\s*/>"#).unwrap();
-    let mut result = template.to_string();
-    let mut iteration = 0;
-    const MAX_ITERATIONS: usize = 10;
+fn parse_tag(chars: &[char], start: usize) -> Option<(String, HashMap<String, String>, usize)> {
+    let mut i = start + 2; // Skip $<
+
+    // Skip whitespace
+    while i < chars.len() && chars[i].is_whitespace() {
+        i += 1;
+    }
+
+    // Parse tag name
+    let mut tag_name = String::new();
+    while i < chars.len() && !chars[i].is_whitespace() && chars[i] != '/' && chars[i] != '>' {
+        tag_name.push(chars[i]);
+        i += 1;
+    }
+
+    if tag_name.is_empty() {
+        return None;
+    }
+
+    // Parse attributes
+    let mut attrs = HashMap::new();
 
     loop {
-        iteration += 1;
-        if iteration > MAX_ITERATIONS {
-            return Err("Too many nested includes (max 10)".to_string());
+        // Skip whitespace
+        while i < chars.len() && chars[i].is_whitespace() {
+            i += 1;
         }
 
-        let result_copy = result.clone();
-        let captures: Vec<_> = include_regex.captures_iter(&result_copy).collect();
-
-        if captures.is_empty() {
-            break;
+        // Check for end of tag
+        if i >= chars.len() {
+            return None;
         }
 
-        for cap in captures {
-            let full_match = cap.get(0).unwrap().as_str();
-            let src = cap.get(1).unwrap().as_str();
+        if chars[i] == '/' {
+            i += 1;
+            if i < chars.len() && chars[i] == '>' {
+                return Some((tag_name, attrs, i + 1));
+            }
+            return None;
+        }
+
+        if chars[i] == '>' {
+            return Some((tag_name, attrs, i + 1));
+        }
+
+        // Parse attribute name
+        let mut attr_name = String::new();
+        while i < chars.len() && chars[i] != '=' && !chars[i].is_whitespace() {
+            attr_name.push(chars[i]);
+            i += 1;
+        }
+
+        if attr_name.is_empty() {
+            return None;
+        }
+
+        // Skip whitespace
+        while i < chars.len() && chars[i].is_whitespace() {
+            i += 1;
+        }
+
+        // Expect =
+        if i >= chars.len() || chars[i] != '=' {
+            return None;
+        }
+        i += 1;
+
+        // Skip whitespace
+        while i < chars.len() && chars[i].is_whitespace() {
+            i += 1;
+        }
+
+        // Parse attribute value (quoted)
+        if i >= chars.len() || chars[i] != '"' {
+            return None;
+        }
+        i += 1; // Skip opening quote
+
+        let mut attr_value = String::new();
+        while i < chars.len() && chars[i] != '"' {
+            attr_value.push(chars[i]);
+            i += 1;
+        }
+
+        if i >= chars.len() {
+            return None;
+        }
+        i += 1; // Skip closing quote
+
+        attrs.insert(attr_name, attr_value);
+    }
+}
+
+fn process_tag(
+    tag_name: &str,
+    attrs: &HashMap<String, String>,
+    post_manager: &PostManager,
+    current_post: Option<&str>,
+    depth: usize,
+) -> Result<String, String> {
+    match tag_name {
+        "include" => {
+            let src = attrs.get("src")
+                .ok_or_else(|| "include tag missing 'src' attribute".to_string())?;
 
             let include_path = format!("templates/{}", src);
             let content = fs::read_to_string(&include_path)
                 .map_err(|e| format!("Failed to read include file '{}': {}", src, e))?;
 
-            result = result.replace(full_match, &content);
+            // Recursively parse the included content
+            parse_template(&content, post_manager, current_post, depth + 1)
         }
-    }
 
-    Ok(result)
-}
+        "post-html" => {
+            let post_name = current_post
+                .ok_or_else(|| "post-html tag used outside of post context".to_string())?;
 
-fn process_post_html(
-    template: &str,
-    post_manager: &PostManager,
-    post_name: &str,
-) -> Result<String, String> {
-    let post_html_regex = Regex::new(r"\$<post-html\s*/?>").unwrap();
+            let post = post_manager
+                .get_post(post_name)
+                .ok_or_else(|| format!("Post '{}' not found", post_name))?;
 
-    let post = post_manager
-        .get_post(post_name)
-        .ok_or_else(|| format!("Post '{}' not found", post_name))?;
-
-    Ok(post_html_regex.replace_all(template, post.html_content.as_str()).to_string())
-}
-
-fn process_post_list(
-    template: &str,
-    post_manager: &PostManager,
-) -> Result<String, String> {
-    let post_list_regex = Regex::new(r#"\$<post-list(?:\s+limit=(\d+))?\s*/>"#).unwrap();
-
-    let mut result = template.to_string();
-
-    for cap in post_list_regex.captures_iter(template) {
-        let full_match = cap.get(0).unwrap().as_str();
-        let limit_attr = cap.get(1).and_then(|m| m.as_str().parse::<usize>().ok());
-
-        let limit = limit_attr;
-
-        let posts = if let Some(l) = limit {
-            post_manager.get_posts_limited(l)
-        } else {
-            post_manager.get_all_posts()
-        };
-
-        let mut list_html = String::from("<ul class=\"post-list\">\n");
-        for post in posts {
-            list_html.push_str(&format!(
-                "  <li><a href=\"/p/{}\">{}</a> <span class=\"date\">{}</span></li>\n",
-                post.name,
-                post.name,
-                post.created_at.format("%Y-%m-%d")
-            ));
+            Ok(post.html_content.clone())
         }
-        list_html.push_str("</ul>");
 
-        result = result.replace(full_match, &list_html);
+        "post-list" => {
+            let limit = attrs.get("limit")
+                .and_then(|s| s.parse::<usize>().ok());
+
+            let posts = if let Some(l) = limit {
+                post_manager.get_posts_limited(l)
+            } else {
+                post_manager.get_all_posts()
+            };
+
+            let mut list_html = String::from("<ul class=\"post-list\">\n");
+            for post in posts {
+                list_html.push_str(&format!(
+                    "  <li><a href=\"/p/{}\">{}</a> <span class=\"date\">{}</span></li>\n",
+                    post.name,
+                    post.name,
+                    post.created_at.format("%Y-%m-%d")
+                ));
+            }
+            list_html.push_str("</ul>");
+
+            Ok(list_html)
+        }
+
+        _ => Err(format!("Unknown tag: {}", tag_name))
     }
-
-    Ok(result)
 }
 
 #[cfg(test)]
@@ -113,26 +203,50 @@ mod tests {
     use super::*;
 
     #[test]
-    fn test_post_list_regex() {
-        let regex = Regex::new(r#"\$<post-list(?:\s+limit=(\d+))?\s*/>"#).unwrap();
+    fn test_parse_tag_post_list() {
+        let chars: Vec<char> = "$<post-list/>".chars().collect();
+        let result = parse_tag(&chars, 0);
+        assert!(result.is_some());
+        let (tag_name, attrs, _) = result.unwrap();
+        assert_eq!(tag_name, "post-list");
+        assert!(attrs.is_empty());
 
-        assert!(regex.is_match("$<post-list/>"));
-        assert!(regex.is_match("$<post-list />"));
-        assert!(regex.is_match("$<post-list limit=50/>"));
-        assert!(regex.is_match("$<post-list limit=50 />"));
+        let chars: Vec<char> = "$<post-list />".chars().collect();
+        let result = parse_tag(&chars, 0);
+        assert!(result.is_some());
 
-        let cap = regex.captures("$<post-list limit=50/>").unwrap();
-        assert_eq!(cap.get(1).unwrap().as_str(), "50");
+        let chars: Vec<char> = r#"$<post-list limit="50"/>"#.chars().collect();
+        let result = parse_tag(&chars, 0);
+        assert!(result.is_some());
+        let (tag_name, attrs, _) = result.unwrap();
+        assert_eq!(tag_name, "post-list");
+        assert_eq!(attrs.get("limit"), Some(&"50".to_string()));
     }
 
     #[test]
-    fn test_include_regex() {
-        let regex = Regex::new(r#"\$<include\s+src="([^"]+)"\s*/>"#).unwrap();
+    fn test_parse_tag_include() {
+        let chars: Vec<char> = r#"$<include src="header.html"/>"#.chars().collect();
+        let result = parse_tag(&chars, 0);
+        assert!(result.is_some());
+        let (tag_name, attrs, _) = result.unwrap();
+        assert_eq!(tag_name, "include");
+        assert_eq!(attrs.get("src"), Some(&"header.html".to_string()));
 
-        assert!(regex.is_match(r#"$<include src="header.html"/>"#));
-        assert!(regex.is_match(r#"$<include src="header.html" />"#));
+        let chars: Vec<char> = r#"$<include src="header.html" />"#.chars().collect();
+        let result = parse_tag(&chars, 0);
+        assert!(result.is_some());
+        let (tag_name, attrs, _) = result.unwrap();
+        assert_eq!(tag_name, "include");
+        assert_eq!(attrs.get("src"), Some(&"header.html".to_string()));
+    }
 
-        let cap = regex.captures(r#"$<include src="header.html"/>"#).unwrap();
-        assert_eq!(cap.get(1).unwrap().as_str(), "header.html");
+    #[test]
+    fn test_parse_tag_post_html() {
+        let chars: Vec<char> = "$<post-html/>".chars().collect();
+        let result = parse_tag(&chars, 0);
+        assert!(result.is_some());
+        let (tag_name, attrs, _) = result.unwrap();
+        assert_eq!(tag_name, "post-html");
+        assert!(attrs.is_empty());
     }
 }