Implement render post

src/main.rs

     }
 }
 
+fn render_post(cwd: &path::PathBuf, layout: &str, post: &Post) {
+    let post_template = fs::read_to_string(cwd.join("templates").join("post.html"))
+        .expect("Couldn't find post template");
+    let output = layout.replace(
+        "{{ contents }}",
+        &post_template
+            .replace("{{ title }}", &post.title)
+            .replace("{{ body }}", &post.body),
+    );
+    match fs::create_dir(cwd.join("public").join(&post.slug)) {
+        Ok(_) => {}
+        Err(err) => match err.kind() {
+            std::io::ErrorKind::AlreadyExists => {}
+            _ => panic!(err),
+        },
+    }
+    fs::write(
+        cwd.join("public").join(&post.slug).join("index.html"),
+        &output,
+    ).expect("Unable to write file");
+}
+
 fn render_post_listing(cwd: &path::PathBuf, layout: &str, posts: &Vec<Post>) {
     let post_listing = posts
         .iter()
         match path {
             Ok(p) => {
                 let post = parse_post(p.path());
+                render_post(&cwd, &layout, &post);
                 posts.push(post);
             }
             Err(err) => panic!(err),