chore(examples): Modify example to include diff utility

2 files changed, 70 insertions, 4 deletions

diff --git a/examples/request_blocking_to_gemtext_from_ast.rs b/examples/request_blocking_to_gemtext_from_ast.rs
index 0e3992d..3c0ff12 100644
--- a/examples/request_blocking_to_gemtext_from_ast.rs
+++ b/examples/request_blocking_to_gemtext_from_ast.rs
@@ -3,9 +3,21 @@
 //! and converting the abstract syntax tree back to Gemtext, identical to the
 //! Gemini response content.
 
+use std::env;
+
 fn main() {
+  // Try to obtain a URL from the command line arguments or use the default one
+  let url_string =
+    env::args().nth(1).unwrap_or_else(|| "gemini://fuwn.me/".to_string());
   // Form a valid URL to a Gemini capsule
-  let url = url::Url::parse("gemini://fuwn.me/").unwrap();
+  let url = match url::Url::parse(&url_string) {
+    Ok(url) => url,
+    Err(error) => {
+      eprintln!("Error parsing URL '{}': {}", url_string, error);
+      std::process::exit(1);
+    }
+  };
+
   // Perform a blocking request to the Gemini capsule
   let request = germ::request::blocking::request(&url);
 
@@ -23,9 +35,60 @@ fn main() {
       let gemtext = ast.to_gemtext();
 
       // Print the Gemtext
-      println!("{}", gemtext)
+      println!("{}", gemtext);
+
+      // Check if the response content and reconstruction are identical
+      if response_content == gemtext {
+        println!(
+          "\nValidation: Response content and reconstruction are identical"
+        );
+      } else {
+        println!("\nValidation: Response content and reconstruction differ");
+        print_diff(response_content, &gemtext);
+      }
+    }
+    // If the request was unsuccessful, print an error message and exit
+    Err(error) => {
+      eprintln!("Error fetching '{}': {}", url_string, error);
+      std::process::exit(1);
+    }
+  }
+}
+
+fn print_diff(original: &str, reconstructed: &str) {
+  use std::io::{self, Write};
+
+  let mut stdout = io::stdout();
+  let original_lines = original.lines().collect::<Vec<&str>>();
+  let reconstructed_lines = reconstructed.lines().collect::<Vec<&str>>();
+  let max_lines = original_lines.len().max(reconstructed_lines.len());
+  let mut has_printed_diff = false;
+
+  for i in 0..max_lines {
+    let original_line = original_lines.get(i).unwrap_or(&"");
+    let reconstructed_line = reconstructed_lines.get(i).unwrap_or(&"");
+
+    if original_line != reconstructed_line {
+      if has_printed_diff {
+        let _ = writeln!(stdout);
+      }
+
+      let _ = writeln!(stdout, "Line {}:", i + 1);
+      let _ = writeln!(stdout, "  Original:      '{}'", original_line);
+      let _ = writeln!(stdout, "  Reconstructed: '{}'", reconstructed_line);
+
+      has_printed_diff = true;
     }
-    // If the request was unsuccessful, do nothing
-    Err(_) => {}
+  }
+
+  if original_lines.len() != reconstructed_lines.len() {
+    if has_printed_diff {
+      let _ = writeln!(stdout);
+    }
+
+    let _ = writeln!(stdout, "Length difference:");
+    let _ = writeln!(stdout, "  Original:      {} lines", original_lines.len());
+    let _ =
+      writeln!(stdout, "  Reconstructed: {} lines", reconstructed_lines.len());
   }
 }
diff --git a/justfile b/justfile
index 9c142cc..e93776d 100644
--- a/justfile
+++ b/justfile
@@ -19,3 +19,6 @@ docs:
 
 example example:
   cargo run --example {{ example }} --all-features
+
+diff url="gemini://fuwn.me/":
+  cargo run --example request_blocking_to_gemtext_from_ast --all-features -- {{ url }}