Copying / Dragging image files (MacOS Terminal + iTerm) (#2567)

In this PR:

- [x] Add support for dragging / copying image files into chat.
- [x] Don't remove image placeholders when submitting.
- [x] Add tests.

Works for:

- Image Files
- Dragging MacOS Screenshots (Terminal, iTerm)

Todos:

- [ ] In some terminals (VSCode, WIndows Powershell, and remote
SSH-ing), copy-pasting a file streams the escaped filepath as individual
key events rather than a single Paste event. We'll need to have a
function (in a separate PR) for detecting these paste events.

codex-rs/tui/src/bottom_pane/chat_composer.rs

@@ -29,6 +29,8 @@ use crate::app_event::AppEvent;
 use crate::app_event_sender::AppEventSender;
 use crate::bottom_pane::textarea::TextArea;
 use crate::bottom_pane::textarea::TextAreaState;
+use crate::clipboard_paste::normalize_pasted_path;
+use crate::clipboard_paste::pasted_image_format;
 use codex_file_search::FileMatch;
 use std::cell::RefCell;
 use std::collections::HashMap;
@@ -220,6 +222,8 @@ impl ChatComposer {
             let placeholder = format!("[Pasted Content {char_count} chars]");
             self.textarea.insert_element(&placeholder);
             self.pending_pastes.push((placeholder, pasted));
+        } else if self.handle_paste_image_path(pasted.clone()) {
+            self.textarea.insert_str(" ");
         } else {
             self.textarea.insert_str(&pasted);
         }
@@ -232,6 +236,25 @@ impl ChatComposer {
         true
     }
 
+    pub fn handle_paste_image_path(&mut self, pasted: String) -> bool {
+        let Some(path_buf) = normalize_pasted_path(&pasted) else {
+            return false;
+        };
+
+        match image::image_dimensions(&path_buf) {
+            Ok((w, h)) => {
+                tracing::info!("OK: {pasted}");
+                let format_label = pasted_image_format(&path_buf).label();
+                self.attach_image(path_buf, w, h, format_label);
+                true
+            }
+            Err(err) => {
+                tracing::info!("ERR: {err}");
+                false
+            }
+        }
+    }
+
     /// Replace the entire composer content with `text` and reset cursor.
     pub(crate) fn set_text_content(&mut self, text: String) {
         self.textarea.set_text(&text);
@@ -730,13 +753,6 @@ impl ChatComposer {
                 }
                 self.pending_pastes.clear();
 
-                // Strip image placeholders from the submitted text; images are retrieved via take_recent_submission_images()
-                for img in &self.attached_images {
-                    if text.contains(&img.placeholder) {
-                        text = text.replace(&img.placeholder, "");
-                    }
-                }
-
                 text = text.trim().to_string();
                 if !text.is_empty() {
                     self.history.record_local_submission(&text);
@@ -1236,7 +1252,10 @@ impl WidgetRef for ChatComposer {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use image::ImageBuffer;
+    use image::Rgba;
     use std::path::PathBuf;
+    use tempfile::tempdir;
 
     use crate::app_event::AppEvent;
     use crate::bottom_pane::AppEventSender;
@@ -1819,7 +1838,7 @@ mod tests {
         let (result, _) =
             composer.handle_key_event(KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE));
         match result {
-            InputResult::Submitted(text) => assert_eq!(text, "hi"),
+            InputResult::Submitted(text) => assert_eq!(text, "[image 32x16 PNG] hi"),
             _ => panic!("expected Submitted"),
         }
         let imgs = composer.take_recent_submission_images();
@@ -1837,7 +1856,7 @@ mod tests {
         let (result, _) =
             composer.handle_key_event(KeyEvent::new(KeyCode::Enter, KeyModifiers::NONE));
         match result {
-            InputResult::Submitted(text) => assert!(text.is_empty()),
+            InputResult::Submitted(text) => assert_eq!(text, "[image 10x5 PNG]"),
             _ => panic!("expected Submitted"),
         }
         let imgs = composer.take_recent_submission_images();
@@ -1913,4 +1932,25 @@ mod tests {
             "one image mapping remains"
         );
     }
+
+    #[test]
+    fn pasting_filepath_attaches_image() {
+        let tmp = tempdir().expect("create TempDir");
+        let tmp_path: PathBuf = tmp.path().join("codex_tui_test_paste_image.png");
+        let img: ImageBuffer<Rgba<u8>, Vec<u8>> =
+            ImageBuffer::from_fn(3, 2, |_x, _y| Rgba([1, 2, 3, 255]));
+        img.save(&tmp_path).expect("failed to write temp png");
+
+        let (tx, _rx) = unbounded_channel::<AppEvent>();
+        let sender = AppEventSender::new(tx);
+        let mut composer =
+            ChatComposer::new(true, sender, false, "Ask Codex to do anything".to_string());
+
+        let needs_redraw = composer.handle_paste(tmp_path.to_string_lossy().to_string());
+        assert!(needs_redraw);
+        assert!(composer.textarea.text().starts_with("[image 3x2 PNG] "));
+
+        let imgs = composer.take_recent_submission_images();
+        assert_eq!(imgs, vec![tmp_path.clone()]);
+    }
 }