Add module output.rs for image file path

- Modularity
- Avoid code duplication
- FIx comments in `core.rs`

src/core.rs

@@ -52,7 +52,7 @@ impl XContext {
 ///
 /// `ctxt`  – connection + screen info\
 /// `x_coord,y_coord` – top-left corner of the rectangle\
-/// `w,h` – size of the rectangle  
+/// `width,height` – size of the rectangle  
 ///
 /// Returns: a `Vec<u8>` containing RGBA pixel data.
 pub fn capture_rect(

src/fullscreen.rs

@@ -1,8 +1,8 @@
 mod core;
+mod output;
 
-use chrono::Local;
 use core::{XContext, capture_rect, save_png};
-use std::fs;
+use output::make_screenshot_path;
 
 fn main() -> anyhow::Result<()> {
     // Create a connection to the X11 server and read screen information.
@@ -12,31 +12,13 @@ fn main() -> anyhow::Result<()> {
     // We pass (0,0) as the top-left corner and use the screen width/height.
     let img = capture_rect(&ctx, 0, 0, ctx.width, ctx.height)?;
 
-    // Build the output file path.
-    // Example:
-    //   ~/Pictures/Screenshots/screenshot_20250116094530.png
-    //
-    // Using a timestamp prevents overwriting old screenshots.
-    let timestamp = Local::now().format("%Y%m%d%H%M%S").to_string();
-
-    // Start from the user's home directory (fallback: current dir).
-    let mut path = dirs::home_dir().unwrap_or_else(|| ".".into());
-    path.push("Pictures");
-    path.push("Screenshots");
-
-    // Make sure the directory exists.
-    fs::create_dir_all(&path)?;
-
-    // Add the actual filename.
-    path.push(format!("screenshot_{timestamp}.png"));
-
-    // Convert path to string for save_png().
+    // Output file path
+    let path = make_screenshot_path()?;
     let path_str = path.to_string_lossy();
 
     // Write the captured RGBA image to a PNG file.
     save_png(&path_str, ctx.width, ctx.height, &img)?;
 
-    println!("Saved {path_str}");
-
+    println!("Saved screenshot: {path_str}");
     Ok(())
 }

src/output.rs

@@ -0,0 +1,26 @@
+use chrono::Local;
+use dirs::home_dir;
+use std::fs;
+use std::path::PathBuf;
+
+/// Build the full output path:
+/// ```
+///     ~/Pictures/Screenshots/screenshot_YYYYMMDDHHMMSS.png
+/// ```
+/// The directory is created automatically if it doesn't exist.
+pub fn make_screenshot_path() -> anyhow::Result<PathBuf> {
+    let timestamp = Local::now().format("%Y%m%d%H%M%S").to_string();
+
+    // Get $HOME (fallback: current working directory)
+    let mut path = home_dir().unwrap_or_else(|| ".".into());
+    path.push("Pictures");
+    path.push("Screenshots");
+
+    // Ensure the directory exists.
+    fs::create_dir_all(&path)?;
+
+    // Add filename.
+    path.push(format!("screenshot_{timestamp}.png"));
+
+    Ok(path)
+}

src/window.rs

@@ -1,9 +1,10 @@
 mod core;
+mod output;
 
 use core::{XContext, capture_rect, save_png};
+use output::make_screenshot_path;
 
-use chrono::Local;
-use std::fs;
+use std::convert::TryFrom;
 use x11rb::protocol::xproto::{AtomEnum, ConnectionExt, GetGeometryReply, Window};
 
 fn main() -> anyhow::Result<()> {
@@ -11,34 +12,27 @@ fn main() -> anyhow::Result<()> {
     let ctx = XContext::new()?;
 
     // Try to get the currently active window using EWMH (_NET_ACTIVE_WINDOW).
-    let window = get_active_window(&ctx).unwrap_or_else(|| {
-        eprintln!("Could not get active window. Falling back to input focus.");
-        get_focused_window(&ctx).unwrap_or(ctx.root)
-    });
+    let window = get_active_window(&ctx)
+        .or_else(|| get_focused_window(&ctx))
+        .unwrap_or(ctx.root);
 
     // Read the size and position of that window.
     let geom = get_window_geometry(&ctx, window)?;
 
-    let x = u16::try_from(geom.x.max(0)).unwrap();
-    let y = u16::try_from(geom.y.max(0)).unwrap();
+    let x = u16::try_from(geom.x.max(0))?;
+    let y = u16::try_from(geom.y.max(0))?;
 
     // Capture only the window rectangle.
     let img = capture_rect(&ctx, x, y, geom.width, geom.height)?;
 
-    // Build output path: ~/Pictures/Screenshots/window_TIMESTAMP.png
-    let timestamp = Local::now().format("%Y%m%d%H%M%S").to_string();
-
-    let mut path = dirs::home_dir().unwrap_or_else(|| ".".into());
-    path.push("Pictures");
-    path.push("Screenshots");
-    fs::create_dir_all(&path)?;
-    path.push(format!("window_{timestamp}.png"));
-
+    // Get output file path
+    let path = make_screenshot_path()?;
     let path_str = path.to_string_lossy();
+
+    // Save image to path
     save_png(&path_str, geom.width, geom.height, &img)?;
 
-    println!("Saved {path_str}");
-
+    println!("Saved screenshot: {path_str}");
     Ok(())
 }