better error handlers in rust and some UI improvement

2025-09-23 18:21:23 +02:00
parent 468717038e
commit 9d0bbf0f88
3 changed files with 70 additions and 25 deletions
--- a/fastmd/src/main.rs
+++ b/fastmd/src/main.rs
@@ -1,37 +1,82 @@
 use std::{env, fs, process};
 use pulldown_cmark::{Parser, Options, html};
+use std::path::PathBuf;

-fn main() {
-    // Get the file path from CLI args
-    let args: Vec<String> = env::args().collect();
-    if args.len() != 2 {
-        eprintln!("Usage: {} <markdown_file>", args[0]);
-        process::exit(1);
+#[derive(Debug)]
+enum MarkdownError {
+    IoError(std::io::Error),
+    InvalidArgs,
+    InvalidFileType,
+}
+
+impl From<std::io::Error> for MarkdownError {
+    fn from(err: std::io::Error) -> Self {
+        MarkdownError::IoError(err)
    }
+}

-    let path = &args[1];
-
-    // Read file contents
-    let markdown = match fs::read_to_string(path) {
-        Ok(content) => content,
-        Err(e) => {
-            eprintln!("Error reading {}: {}", path, e);
-            process::exit(1);
+impl std::fmt::Display for MarkdownError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            MarkdownError::IoError(e) => write!(f, "IO error: {}", e),
+            MarkdownError::InvalidArgs => write!(f, "Invalid arguments provided"),
+            MarkdownError::InvalidFileType => write!(f, "File extension should be .md or .markdown"),
        }
-    };
+    }
+}

-    // Configure parser with GitHub-flavored options
+fn markdown_to_html(markdown: &str, body_top_content: &str) -> String {
    let mut options = Options::empty();
    options.insert(Options::ENABLE_TABLES);
    options.insert(Options::ENABLE_FOOTNOTES);
    options.insert(Options::ENABLE_STRIKETHROUGH);
    options.insert(Options::ENABLE_TASKLISTS);

-    // Parse and render to HTML
-    let parser = Parser::new_ext(&markdown, options);
+    let parser = Parser::new_ext(markdown, options);
    let mut html_output = String::new();
    html::push_html(&mut html_output, parser);
-
-    // Print only the body content (no <html>/<head>)
-    println!("{} <!-- this was generated from rust with pulldown_cmark ; REASON: Large File -->", html_output);
+    
+    // If body_top_content is not empty, wrap the output
+    if !body_top_content.trim().is_empty() {
+        format!("{}\n{}", body_top_content, html_output)
+    } else {
+        html_output
+    }
+}
+
+fn validate_file_type(path: &PathBuf) -> Result<(), MarkdownError> {
+    if let Some(ext) = path.extension() {
+        if ext == "md" || ext == "markdown" {
+            Ok(())
+        } else {
+            Err(MarkdownError::InvalidFileType)
+        }
+    } else {
+        Err(MarkdownError::InvalidFileType)
+    }
+}
+
+fn run() -> Result<String, MarkdownError> {
+    let args: Vec<String> = env::args().collect();
+    if args.len() != 2 {
+        return Err(MarkdownError::InvalidArgs);
+    }
+
+    let path = PathBuf::from(&args[1]);
+    validate_file_type(&path)?;
+    let markdown = fs::read_to_string(&path)?;
+    let top_content = "<!-- This was automatically parsed with fastmd (Rust Markdown Parser) -->";
+    Ok(markdown_to_html(&markdown, top_content))
+}
+
+fn main() {
+    match run() {
+        Ok(html_output) => {
+            println!("{}", html_output);
+        }
+        Err(e) => {
+            eprintln!("Error: {}", e);
+            process::exit(1);
+        }
+    }
 }